Tag Archives: Drought

Global water supply shrinks in rainier world

The global water supply is dwindling, even though rainfall is heavier. Once again, climate change is to blame.

LONDON, 20 December, 2018 – Even in a world with more intense rain, communities could begin to run short of water. New research has confirmed that, in a warming world, extremes of drought have begun to diminish the world’s groundwater – and ever more intense rainstorms will do little to make up the loss in the global water supply.

And a second, separate study delivers support for this seeming paradox: worldwide, there is evidence that rainfall patterns are, increasingly, being disturbed. The number of record-dry months has increased overall. And so has the number of record-breaking rainy months.

Both studies match predictions in a world of climate change driven by ever-higher ratios of greenhouse gases in the atmosphere, from ever-increasing combustion of fossil fuels. But, unlike many climate studies, neither of these is based on computer simulation of predicted change.

Each is instead based on the meticulous analysis of huge quantities of on-the-ground data. Together they provide substance to a 40-year-old prediction of climate change research: that in a warming world, those regions already wet will get ever more rain, while the drylands will tend to become increasingly more arid.

As global temperatures creep up – and they have already risen by 1°C in the past century, and could be set to reach 3°C by 2100 – so does the capacity of the atmosphere to absorb more moisture. It follows that more rain must fall. But at the same time more groundwater evaporates, and the risk of damaging drought increases.

“What we did not expect, despite all the extra rain everywhere in the world, is that the large rivers are drying out”

Australian scientists report in the journal Water Resources Research that they studied readings from 43,000 rainfall stations and 5,300 river monitoring sites in 160 countries. And they confirm that even in a world of more intense rain, drought could become the new normal in those regions already at risk.

“This is something that has been missed. We expected rainfall to increase, since warmer air stores more moisture – and that is what climate models predicted too,” said Ashish Sharma, an environmental engineer at the University of New South Wales.

“What we did not expect, despite all the extra rain everywhere in the world, is that the large rivers are drying out. We believe the cause is the drying of soils in our catchments. Where once these were moist before a storm event – allowing excess rainfall to run off into rivers – they are now drier and soak up more rain, so less water makes it as flow.”

The study matches predictions. Just in the last few months, climate scientists have warned that catastrophic climate change could be on the way, and that the double hazard of heat waves and sustained drought could devastate harvests in more than one climatic zone in the same season; and that those landlocked rainfall catchment areas that are already dry are becoming increasingly more parched.

But over the same few months, researchers have established repeatedly that tomorrow’s storms will be worse and that more devastating flash floods can be expected even in one of the world’s driest continents, Australia itself.

Less water available

Of all rainfall, only 36% gets into aquifers, streams and lakes. The remaining two thirds seeps into the soils, grasslands and woodlands. But more soil evaporation means less water is available from river supplies for cities and farms.

US researchers have already confirmed that if soils are moist before a storm, 62% of rainfall leads to floods that fill catchments. If soils are dry, only 13% of the rain leads to flooding.

“It’s a double whammy. Less water is ending up where we can’t store it for later use. At the same time, more rain is overwhelming drainage infrastructure in towns and cities, leading to more urban flooding,” said Professor Sharma.

“Small floods are very important for water supply, because they refill dams and form the basis of our water supply. But they’re happening less often, because the soils are sucking up extra rain. Even when a major storm dumps a lot of rain, the soils are so dry they absorb more water than before, and less reaches the rivers and reservoirs”, he said. “We need to adapt to this emerging reality.”

In the second close look at change so far, researchers based in Germany report in the journal Geophysical Research Letters  that they analysed data from 50,000 weather stations worldwide to measure rainfall on a monthly basis.

Climate drives aridity

The US has seen a more than 25% increase of record wet months in the eastern and central regions between 1980 and 2013. Argentina has seen a 32% increase. In central and northern Europe the increase is between 19% and 37%; in Asian Russia, it has been about 20%.

But in Africa south of the Sahara the incidence of very dry months has increased by 50%. “This implies that approximately one out of three record dry months in this region would not have occurred without long-term climate change,” said Dim Coumou, of the Potsdam Institute for Climate Impact Research.

“Generally, land regions in the tropics and sub-tropics have seen more dry records, and the northern mid- to high-latitudes more wet records. This largely fits the patterns that scientists expect from human-caused climate change.”

His colleague and lead author Jascha Lehmann said: “Normally, record weather events occur by chance and we know how many would happen in a climate without warning. It’s like throwing a dice: on average one out of six times you get a six.

“But by injecting huge amounts of greenhouse gases into the atmosphere, humankind has loaded the dice. In many regions, we throw sixes much more often, with severe impacts for society and the environment.

“It is worrying that we see significant increases of such extremes with just one degree of global warming.” – Climate News Network

The global water supply is dwindling, even though rainfall is heavier. Once again, climate change is to blame.

LONDON, 20 December, 2018 – Even in a world with more intense rain, communities could begin to run short of water. New research has confirmed that, in a warming world, extremes of drought have begun to diminish the world’s groundwater – and ever more intense rainstorms will do little to make up the loss in the global water supply.

And a second, separate study delivers support for this seeming paradox: worldwide, there is evidence that rainfall patterns are, increasingly, being disturbed. The number of record-dry months has increased overall. And so has the number of record-breaking rainy months.

Both studies match predictions in a world of climate change driven by ever-higher ratios of greenhouse gases in the atmosphere, from ever-increasing combustion of fossil fuels. But, unlike many climate studies, neither of these is based on computer simulation of predicted change.

Each is instead based on the meticulous analysis of huge quantities of on-the-ground data. Together they provide substance to a 40-year-old prediction of climate change research: that in a warming world, those regions already wet will get ever more rain, while the drylands will tend to become increasingly more arid.

As global temperatures creep up – and they have already risen by 1°C in the past century, and could be set to reach 3°C by 2100 – so does the capacity of the atmosphere to absorb more moisture. It follows that more rain must fall. But at the same time more groundwater evaporates, and the risk of damaging drought increases.

“What we did not expect, despite all the extra rain everywhere in the world, is that the large rivers are drying out”

Australian scientists report in the journal Water Resources Research that they studied readings from 43,000 rainfall stations and 5,300 river monitoring sites in 160 countries. And they confirm that even in a world of more intense rain, drought could become the new normal in those regions already at risk.

“This is something that has been missed. We expected rainfall to increase, since warmer air stores more moisture – and that is what climate models predicted too,” said Ashish Sharma, an environmental engineer at the University of New South Wales.

“What we did not expect, despite all the extra rain everywhere in the world, is that the large rivers are drying out. We believe the cause is the drying of soils in our catchments. Where once these were moist before a storm event – allowing excess rainfall to run off into rivers – they are now drier and soak up more rain, so less water makes it as flow.”

The study matches predictions. Just in the last few months, climate scientists have warned that catastrophic climate change could be on the way, and that the double hazard of heat waves and sustained drought could devastate harvests in more than one climatic zone in the same season; and that those landlocked rainfall catchment areas that are already dry are becoming increasingly more parched.

But over the same few months, researchers have established repeatedly that tomorrow’s storms will be worse and that more devastating flash floods can be expected even in one of the world’s driest continents, Australia itself.

Less water available

Of all rainfall, only 36% gets into aquifers, streams and lakes. The remaining two thirds seeps into the soils, grasslands and woodlands. But more soil evaporation means less water is available from river supplies for cities and farms.

US researchers have already confirmed that if soils are moist before a storm, 62% of rainfall leads to floods that fill catchments. If soils are dry, only 13% of the rain leads to flooding.

“It’s a double whammy. Less water is ending up where we can’t store it for later use. At the same time, more rain is overwhelming drainage infrastructure in towns and cities, leading to more urban flooding,” said Professor Sharma.

“Small floods are very important for water supply, because they refill dams and form the basis of our water supply. But they’re happening less often, because the soils are sucking up extra rain. Even when a major storm dumps a lot of rain, the soils are so dry they absorb more water than before, and less reaches the rivers and reservoirs”, he said. “We need to adapt to this emerging reality.”

In the second close look at change so far, researchers based in Germany report in the journal Geophysical Research Letters  that they analysed data from 50,000 weather stations worldwide to measure rainfall on a monthly basis.

Climate drives aridity

The US has seen a more than 25% increase of record wet months in the eastern and central regions between 1980 and 2013. Argentina has seen a 32% increase. In central and northern Europe the increase is between 19% and 37%; in Asian Russia, it has been about 20%.

But in Africa south of the Sahara the incidence of very dry months has increased by 50%. “This implies that approximately one out of three record dry months in this region would not have occurred without long-term climate change,” said Dim Coumou, of the Potsdam Institute for Climate Impact Research.

“Generally, land regions in the tropics and sub-tropics have seen more dry records, and the northern mid- to high-latitudes more wet records. This largely fits the patterns that scientists expect from human-caused climate change.”

His colleague and lead author Jascha Lehmann said: “Normally, record weather events occur by chance and we know how many would happen in a climate without warning. It’s like throwing a dice: on average one out of six times you get a six.

“But by injecting huge amounts of greenhouse gases into the atmosphere, humankind has loaded the dice. In many regions, we throw sixes much more often, with severe impacts for society and the environment.

“It is worrying that we see significant increases of such extremes with just one degree of global warming.” – Climate News Network

Extremes of heat will hit health and wealth

A new and authoritative study warns of an “overwhelming impact” on public health just from extremes of heat as the world continues to warm.

LONDON, 4 December, 2018 – Vulnerability to extremes of heat has risen in every region of the world. In 2017, an additional 157 million people were exposed in heatwave events, compared with 2000. That means that the average person now experiences 1.4 additional days of heatwaves per year.

This enervating exposure to extended extremes of heat imposes a global cost. National economies – and household budgets – lost 153 billion hours of labour in 2017, because of sweltering days and torrid nights: this is an increase of 62 billion working hours – more than three billion working weeks – since the turn of the century.

The rise in extremes of heat means that more people than ever are potentially at risk of heatwave-related conditions: among them heat stress, cardiovascular illness and kidney disease.

That increasing extremes of heat, driven by ever greater levels of greenhouse gas emissions that fuel global warming and climate change, are a health hazard is now well established.

More fatalities

Researchers have repeatedly warned that any increase in global average temperatures will be measured in more frequent, more intense and more extended extremes of heat
and in some cases extreme humidity that will in turn claim ever greater numbers of lives.

Scientists have established that, by 2100, around three-quarters of humanity will face episodes of heat extremes, which can kill in any one of 27 different ways.

So the latest detailed study, in the journal The Lancet, brings wider focus and greater authority: it draws from scientists and public health professionals in 27 institutions and tracks 421 indicators across five areas, including climate change vulnerability; adaptation and planning for health; mitigation actions and the benefits these may have; finance and economics; and public and political engagement.

Among the indicators selected were weather-related disasters, food security, clean fuel use, meat consumption, air pollution – and scientific publications on climate and health. And although the report echoes the general alarms voiced in earlier studies, it takes a closer look at the details of human vulnerability to extremes of heat.

“Trends in the impacts of climate change, exposures and vulnerabilities show unacceptably high risk for human health”

One finding is that people in Europe and the eastern Mediterranean may be more vulnerable than people living in Africa and southeast Asia, if only because more than four out of 10 people in Europe and the eastern Mediterranean are aged over 65, compared with 38% in Africa and 34% in southeast Asia.

Hotter weather means more infectious disease: in 2016 alone, what the researchers call the “global vectorial capacity” – in other words, the spread of potentially disease-transmitting mosquitoes – of the dengue fever virus was the highest on record.

In the Baltic region, the coastline area vulnerable to an epidemic of the cholera bacterium grew by 24%. In the highlands of sub-Saharan Africa, the area potentially at risk from malaria rose by more than 26%.

And as the thermometer went up, more than 30 countries reported downward trends in agricultural yields. Agriculture is the field most directly hit by heat extremes, with 80% of the labour losses, or 122 billion hours of work abandoned.

Huge losses

“Vulnerability to extreme heat has steadily increased around the world,” said Joacim Rocklöv, of Umea University in Sweden, one of the more than 70 scientists who put their names to the Lancet study.

“This has led to vast losses for national economies and household budgets. At a time when national health budgets and health services face a growing epidemic of lifestyle diseases, continued delay in unlocking the potential health benefits of climate change mitigation is shortsighted and damaging for human health.”

The report emphasises that heat extremes also intensify urban pollution: now 97% of cities in low and middle-income countries no longer meet World Health Organisation air quality guidelines.

“Heat stress is hitting hard – particularly amongst the urban elderly, and those with underlying health conditions such as cardiovascular disease, diabetes or chronic kidney disease,” said Hugh Montgomery, co-chairman of the Lancet Countdown on health and climate change, who also directs the Institute for Human Health and Performance at University College London.

Risky outdoors

“In high temperatures, outdoor work, especially in agriculture, is hazardous. Areas from northern England and California to Australia are seeing savage fires with direct deaths, displacement and loss of housing as well as respiratory impacts from smoke inhalation.”

And Hilary Graham, of the University of York in the UK, another of the authors, warned that the way governments responded to climate change would shape the health of nations for centuries to come.

“Present-day changes in heat waves and labour capacity provide early warning of the compounded and overwhelming impact on public health that is expected if temperatures continue to rise,” she said.

“Trends in the impacts of climate change, exposures and vulnerabilities show unacceptably high risk for human health now and in the future.” – Climate News Network

A new and authoritative study warns of an “overwhelming impact” on public health just from extremes of heat as the world continues to warm.

LONDON, 4 December, 2018 – Vulnerability to extremes of heat has risen in every region of the world. In 2017, an additional 157 million people were exposed in heatwave events, compared with 2000. That means that the average person now experiences 1.4 additional days of heatwaves per year.

This enervating exposure to extended extremes of heat imposes a global cost. National economies – and household budgets – lost 153 billion hours of labour in 2017, because of sweltering days and torrid nights: this is an increase of 62 billion working hours – more than three billion working weeks – since the turn of the century.

The rise in extremes of heat means that more people than ever are potentially at risk of heatwave-related conditions: among them heat stress, cardiovascular illness and kidney disease.

That increasing extremes of heat, driven by ever greater levels of greenhouse gas emissions that fuel global warming and climate change, are a health hazard is now well established.

More fatalities

Researchers have repeatedly warned that any increase in global average temperatures will be measured in more frequent, more intense and more extended extremes of heat
and in some cases extreme humidity that will in turn claim ever greater numbers of lives.

Scientists have established that, by 2100, around three-quarters of humanity will face episodes of heat extremes, which can kill in any one of 27 different ways.

So the latest detailed study, in the journal The Lancet, brings wider focus and greater authority: it draws from scientists and public health professionals in 27 institutions and tracks 421 indicators across five areas, including climate change vulnerability; adaptation and planning for health; mitigation actions and the benefits these may have; finance and economics; and public and political engagement.

Among the indicators selected were weather-related disasters, food security, clean fuel use, meat consumption, air pollution – and scientific publications on climate and health. And although the report echoes the general alarms voiced in earlier studies, it takes a closer look at the details of human vulnerability to extremes of heat.

“Trends in the impacts of climate change, exposures and vulnerabilities show unacceptably high risk for human health”

One finding is that people in Europe and the eastern Mediterranean may be more vulnerable than people living in Africa and southeast Asia, if only because more than four out of 10 people in Europe and the eastern Mediterranean are aged over 65, compared with 38% in Africa and 34% in southeast Asia.

Hotter weather means more infectious disease: in 2016 alone, what the researchers call the “global vectorial capacity” – in other words, the spread of potentially disease-transmitting mosquitoes – of the dengue fever virus was the highest on record.

In the Baltic region, the coastline area vulnerable to an epidemic of the cholera bacterium grew by 24%. In the highlands of sub-Saharan Africa, the area potentially at risk from malaria rose by more than 26%.

And as the thermometer went up, more than 30 countries reported downward trends in agricultural yields. Agriculture is the field most directly hit by heat extremes, with 80% of the labour losses, or 122 billion hours of work abandoned.

Huge losses

“Vulnerability to extreme heat has steadily increased around the world,” said Joacim Rocklöv, of Umea University in Sweden, one of the more than 70 scientists who put their names to the Lancet study.

“This has led to vast losses for national economies and household budgets. At a time when national health budgets and health services face a growing epidemic of lifestyle diseases, continued delay in unlocking the potential health benefits of climate change mitigation is shortsighted and damaging for human health.”

The report emphasises that heat extremes also intensify urban pollution: now 97% of cities in low and middle-income countries no longer meet World Health Organisation air quality guidelines.

“Heat stress is hitting hard – particularly amongst the urban elderly, and those with underlying health conditions such as cardiovascular disease, diabetes or chronic kidney disease,” said Hugh Montgomery, co-chairman of the Lancet Countdown on health and climate change, who also directs the Institute for Human Health and Performance at University College London.

Risky outdoors

“In high temperatures, outdoor work, especially in agriculture, is hazardous. Areas from northern England and California to Australia are seeing savage fires with direct deaths, displacement and loss of housing as well as respiratory impacts from smoke inhalation.”

And Hilary Graham, of the University of York in the UK, another of the authors, warned that the way governments responded to climate change would shape the health of nations for centuries to come.

“Present-day changes in heat waves and labour capacity provide early warning of the compounded and overwhelming impact on public health that is expected if temperatures continue to rise,” she said.

“Trends in the impacts of climate change, exposures and vulnerabilities show unacceptably high risk for human health now and in the future.” – Climate News Network

Farmers face double trouble as world warms

At risk from heat and drought in a warming world, farmers face double trouble in two or more great farming regions at once.

LONDON, 30 November, 2018 – US researchers have confirmed that continued global warming means farmers face double trouble: a heightened possibility of a suddenly hungrier world, as ever-higher average global temperatures increase the probability of devastating heat and drought in two great agricultural regions of the world simultaneously.

This is not the first such warning. In October, a separate team of researchers used a different approach to find that continued climate change could increase the possibility of a return of the conditions that triggered the global drought and famine of 1875-78, which may have claimed 50 million lives.

Also in October, researchers at the University of Washington focused on the possible recurrence of three shifts in regional climate that combined to cause colossal harvest failure in India, China and Brazil.

This time, Californian scientists report in the journal Science Advances that they simply looked at the record of temperature change and the mathematical probabilities associated with it.

In the last century, thanks to profligate combustion of fossil fuels and the consequent increase of greenhouse gases in the atmosphere, the world has warmed on average by around 1°C.

“The default is to use historical probabilities. But … assuming that those historical probabilities will continue into the future doesn’t accurately reflect the current or future risk”

“If it’s getting warmer everywhere, then it’s more likely to be hot in two places at once, and it’s probably also more likely to be hot when it’s also dry in two places at once,” said Noah Diffenbaugh, of Stanford’s school of earth, energy and environmental sciences.

“When we look in the historical data at the key crop and pasture regions, we find that before anthropogenic climate change, there were very low odds that any two regions would experience those really severe conditions simultaneously,” he said.

“The global marketplace provides a hedge against localised extremes, but we’re already seeing an erosion of that climate buffer as extremes have increased in response to global warming.”

For most of human history harvest failure has been a hazard, but losses in one region have usually been balanced by gains in another. The global famine that began with the Asian monsoon failure of 1875 was a rare event, made more damaging by imperial mismanagement by the European powers.

Lengthening odds

But climate change brings with it the double jeopardy of low crop yields in two great zones of agricultural production at the same time. The odds of both low rainfall and high temperatures in the same year in both China and India – two great farming nations, with the two biggest populations – were, in 1980, just one in 20. These have now increased to more than one in seven.

“So what used to be a rare occurrence can now be expected to occur with some regularity, and we have very strong evidence that global warming is the cause,” said Professor Diffenbaugh.

The researchers found that, if the world continued burning fossil fuels under the notorious business-as-usual scenario, the chances that average temperatures would rise well beyond the range normally experienced in the mid-20th century would, in many regions, increase by 75%.

The researchers also found that – were the world to honour the promise of the Paris Climate Accord of 2015, to contain global warming to well below 2°C by 2100 – the risk of double trouble for two separate regions simultaneously is curbed.

Extremes increase

Extremes of heat by themselves pose a risk to crop yields and, increasingly, more parts of the world are more at risk  of harvest losses.

The Californian scientists looked at multiple risks in one region at the same time – high winds, storm surges, calamitous tropical cyclones, and also low humidity, high temperatures, high winds and lethal wild fires – and then the probability that similar or slightly different multiple hazards could overtake another region in the same year.

The implication is that with increasing average global temperatures, the kinds of hazards farmers and communities expect to confront could be about to change. For centuries, societies made decisions based on the probabilities they already understood.

“The default is to use historical probabilities,” said Professor Diffenbaugh. “But our research shows that assuming that those historical probabilities will continue into the future doesn’t accurately reflect the current or future risk.” – Climate News Network

At risk from heat and drought in a warming world, farmers face double trouble in two or more great farming regions at once.

LONDON, 30 November, 2018 – US researchers have confirmed that continued global warming means farmers face double trouble: a heightened possibility of a suddenly hungrier world, as ever-higher average global temperatures increase the probability of devastating heat and drought in two great agricultural regions of the world simultaneously.

This is not the first such warning. In October, a separate team of researchers used a different approach to find that continued climate change could increase the possibility of a return of the conditions that triggered the global drought and famine of 1875-78, which may have claimed 50 million lives.

Also in October, researchers at the University of Washington focused on the possible recurrence of three shifts in regional climate that combined to cause colossal harvest failure in India, China and Brazil.

This time, Californian scientists report in the journal Science Advances that they simply looked at the record of temperature change and the mathematical probabilities associated with it.

In the last century, thanks to profligate combustion of fossil fuels and the consequent increase of greenhouse gases in the atmosphere, the world has warmed on average by around 1°C.

“The default is to use historical probabilities. But … assuming that those historical probabilities will continue into the future doesn’t accurately reflect the current or future risk”

“If it’s getting warmer everywhere, then it’s more likely to be hot in two places at once, and it’s probably also more likely to be hot when it’s also dry in two places at once,” said Noah Diffenbaugh, of Stanford’s school of earth, energy and environmental sciences.

“When we look in the historical data at the key crop and pasture regions, we find that before anthropogenic climate change, there were very low odds that any two regions would experience those really severe conditions simultaneously,” he said.

“The global marketplace provides a hedge against localised extremes, but we’re already seeing an erosion of that climate buffer as extremes have increased in response to global warming.”

For most of human history harvest failure has been a hazard, but losses in one region have usually been balanced by gains in another. The global famine that began with the Asian monsoon failure of 1875 was a rare event, made more damaging by imperial mismanagement by the European powers.

Lengthening odds

But climate change brings with it the double jeopardy of low crop yields in two great zones of agricultural production at the same time. The odds of both low rainfall and high temperatures in the same year in both China and India – two great farming nations, with the two biggest populations – were, in 1980, just one in 20. These have now increased to more than one in seven.

“So what used to be a rare occurrence can now be expected to occur with some regularity, and we have very strong evidence that global warming is the cause,” said Professor Diffenbaugh.

The researchers found that, if the world continued burning fossil fuels under the notorious business-as-usual scenario, the chances that average temperatures would rise well beyond the range normally experienced in the mid-20th century would, in many regions, increase by 75%.

The researchers also found that – were the world to honour the promise of the Paris Climate Accord of 2015, to contain global warming to well below 2°C by 2100 – the risk of double trouble for two separate regions simultaneously is curbed.

Extremes increase

Extremes of heat by themselves pose a risk to crop yields and, increasingly, more parts of the world are more at risk  of harvest losses.

The Californian scientists looked at multiple risks in one region at the same time – high winds, storm surges, calamitous tropical cyclones, and also low humidity, high temperatures, high winds and lethal wild fires – and then the probability that similar or slightly different multiple hazards could overtake another region in the same year.

The implication is that with increasing average global temperatures, the kinds of hazards farmers and communities expect to confront could be about to change. For centuries, societies made decisions based on the probabilities they already understood.

“The default is to use historical probabilities,” said Professor Diffenbaugh. “But our research shows that assuming that those historical probabilities will continue into the future doesn’t accurately reflect the current or future risk.” – Climate News Network

Hotter climate will cost Europe dear

Unrestrained global warming and a hotter climate will cost Europe dear in lives lost and economies squeezed. Even if it’s limited, there’ll be a price to pay.

LONDON, 23 November, 2018 – The continent must brace itself for the big heat: a hotter climate will cost Europe dear if average global temperatures soar by 3°C near the end of the century, when heat extremes could claim an additional 132,000 deaths a year.

Labour productivity in some southern European countries could fall by 10 to 15%. As sea levels rise, there could be a five-fold increase in coastal flood damage, to affect more than 2 million people and wreak economic tolls of €60 billion (US$68 bn) a year.

As extremes of rainfall increase, swollen rivers could expose three times as many people to inland flooding, and the damage from river floods could rise from €5.3m a year to €17.5m.

If, on the other hand, the world keeps the promise it made to itself in Paris in 2015, and contains global warming to 2°C or less by the century’s end, coastal flooding – which already affects 100,000 people and costs €1.25 bn a year – will affect only an estimated 436,000 and total €6 bn a year in annual damage.

Grim appraisal

But right now the world is on course to tip 3°C by the century’s end, and a new study by the European Commission’s joint research centre has made a sombre assessment of the likely costs.

There will be significant shifts in the times at which seeds sprout, flowers bloom and crops ripen, with big changes in soil water: this is going to affect agricultural productivity. Europe’s arid climate zone is expected to double in area.

Demand for energy to heat homes and offices is likely to fall, but any gains will be wiped out by a rapid rise in energy demand to cool cities and towns. Northern Europe can expect to get wetter, but some parts of southern Europe will, increasingly, face drought and water shortages.

Some of the forecasts are not new: researchers have repeatedly examined the impact of climate change on European harvests, and of sea level rise, for instance, on European coastal cities.

Terse summary

The latest report, labelled with the acronym Peseta III, presents a wider picture of change. It has been four years in the making, and is the product of consultation with experts in economics, biology, physics and engineering: its opening abstract says it all in three pithy sentences.

“The study assesses how climate change could affect Europe in eleven impact areas. Under a high warming scenario, several climate impacts show a clear geographical north-south divide. Most of the welfare losses, assessed for six impact areas, would be greatly reduced under a 2°C scenario.”

It attempts to put a crude measurement on the consumer cost to Europe’s economic welfare of various levels of possible climate change, and the headline figure is that 3°C warming could impose losses on the European Union nations of 1.9% of gross domestic product, or €240bn a year.

But this is an understatement “because key climate impacts cannot be quantified,” the researchers say. And once again, losses would be considerably lower if warming was contained to within 2°C.

Some winners

Under a lower warming regime, there could even be some benefits: Eastern Europe in particular could expect to see measurably higher agricultural yields, especially of wheat and maize.

In southern Europe, which will be both drier and warmer, yields are expected to decline. Irrigation may not be the answer: the harvest from irrigated fields is likely to start showing a decline by the mid-2030s.

By 2050, crop prices are likely to be depressed by the impacts of climate change. In effect, farmers could expect lower output, and on top of that, lower incomes per unit of output.

And these calculations do not include the direct impact of weather extremes – the heatwaves that shrivel seedlings, the hailstorms and high winds that damage blossom and so on – that are likely to be amplified by overall global warming.

“Under a high warming scenario, several climate impacts show a clear geographical north-south divide. Most of the welfare losses … would be greatly reduced under a 2°C scenario”

Transport, too, will be at the mercy of ever more intense and more frequent extremes of weather. By the century’s end, 200 airports and 850 seaports – large and small – could be affected by flooding from either rising sea levels or heavier downpours.

And the Mediterranean climate zone – with its unique mix of habitat, ground cover, biodiversity and crops – would become increasingly vulnerable to droughts, fires, pests and invasive alien species.

Labour productivity will fall, especially in the south, and in some places employers might have to plan to shift some work to the cooler night, with the additional costs of chronic fatigue, anxiety and depression associated with night work.

At 3°C, heat extremes could lead to additional deaths per year up to 132,000. But even at 2°C this figure could soar to 58,000 extra deaths per year. – Climate News Network

Unrestrained global warming and a hotter climate will cost Europe dear in lives lost and economies squeezed. Even if it’s limited, there’ll be a price to pay.

LONDON, 23 November, 2018 – The continent must brace itself for the big heat: a hotter climate will cost Europe dear if average global temperatures soar by 3°C near the end of the century, when heat extremes could claim an additional 132,000 deaths a year.

Labour productivity in some southern European countries could fall by 10 to 15%. As sea levels rise, there could be a five-fold increase in coastal flood damage, to affect more than 2 million people and wreak economic tolls of €60 billion (US$68 bn) a year.

As extremes of rainfall increase, swollen rivers could expose three times as many people to inland flooding, and the damage from river floods could rise from €5.3m a year to €17.5m.

If, on the other hand, the world keeps the promise it made to itself in Paris in 2015, and contains global warming to 2°C or less by the century’s end, coastal flooding – which already affects 100,000 people and costs €1.25 bn a year – will affect only an estimated 436,000 and total €6 bn a year in annual damage.

Grim appraisal

But right now the world is on course to tip 3°C by the century’s end, and a new study by the European Commission’s joint research centre has made a sombre assessment of the likely costs.

There will be significant shifts in the times at which seeds sprout, flowers bloom and crops ripen, with big changes in soil water: this is going to affect agricultural productivity. Europe’s arid climate zone is expected to double in area.

Demand for energy to heat homes and offices is likely to fall, but any gains will be wiped out by a rapid rise in energy demand to cool cities and towns. Northern Europe can expect to get wetter, but some parts of southern Europe will, increasingly, face drought and water shortages.

Some of the forecasts are not new: researchers have repeatedly examined the impact of climate change on European harvests, and of sea level rise, for instance, on European coastal cities.

Terse summary

The latest report, labelled with the acronym Peseta III, presents a wider picture of change. It has been four years in the making, and is the product of consultation with experts in economics, biology, physics and engineering: its opening abstract says it all in three pithy sentences.

“The study assesses how climate change could affect Europe in eleven impact areas. Under a high warming scenario, several climate impacts show a clear geographical north-south divide. Most of the welfare losses, assessed for six impact areas, would be greatly reduced under a 2°C scenario.”

It attempts to put a crude measurement on the consumer cost to Europe’s economic welfare of various levels of possible climate change, and the headline figure is that 3°C warming could impose losses on the European Union nations of 1.9% of gross domestic product, or €240bn a year.

But this is an understatement “because key climate impacts cannot be quantified,” the researchers say. And once again, losses would be considerably lower if warming was contained to within 2°C.

Some winners

Under a lower warming regime, there could even be some benefits: Eastern Europe in particular could expect to see measurably higher agricultural yields, especially of wheat and maize.

In southern Europe, which will be both drier and warmer, yields are expected to decline. Irrigation may not be the answer: the harvest from irrigated fields is likely to start showing a decline by the mid-2030s.

By 2050, crop prices are likely to be depressed by the impacts of climate change. In effect, farmers could expect lower output, and on top of that, lower incomes per unit of output.

And these calculations do not include the direct impact of weather extremes – the heatwaves that shrivel seedlings, the hailstorms and high winds that damage blossom and so on – that are likely to be amplified by overall global warming.

“Under a high warming scenario, several climate impacts show a clear geographical north-south divide. Most of the welfare losses … would be greatly reduced under a 2°C scenario”

Transport, too, will be at the mercy of ever more intense and more frequent extremes of weather. By the century’s end, 200 airports and 850 seaports – large and small – could be affected by flooding from either rising sea levels or heavier downpours.

And the Mediterranean climate zone – with its unique mix of habitat, ground cover, biodiversity and crops – would become increasingly vulnerable to droughts, fires, pests and invasive alien species.

Labour productivity will fall, especially in the south, and in some places employers might have to plan to shift some work to the cooler night, with the additional costs of chronic fatigue, anxiety and depression associated with night work.

At 3°C, heat extremes could lead to additional deaths per year up to 132,000. But even at 2°C this figure could soar to 58,000 extra deaths per year. – Climate News Network

Climate impacts will seldom strike singly

Climate impacts aren’t just potentially catastrophic: they could be simultaneous multiple disasters. US scientists have compiled a catalogue of calamity and a map of mayhem.

LONDON, 20 November, 2019 − By 2100, climate impacts will be felt by everyone and most people will experience at least three simultaneous hazards, inexorably made more hazardous by the build-up of greenhouse gases in the atmosphere.

And they could be the lucky ones: some people could be menaced by six different kinds of warming-related hazard simultaneously.

Camilo Mora of the University of Hawaii at Manoa and 22 colleagues report in Nature Climate Change that they read systematically through 3,280 peer-reviewed papers on the subject of climate change, and compiled a matrix of 467 ways in which 10 major climate hazards – floods, droughts, heat waves, fires and so on – and six aspects of human dependency (health, food, water, etc.) could affect humanity.

They did, they say, identify some positive or neutral effects, but the overwhelming majority of climate impacts would create problems for human communities and their economies.

Medical prospects

Dr Mora has established a reputation for thinking on the scale of global catalogue. Recently, the geographer and his fellow researchers looked at medical records and heat extremes and listed 27 different ways in which heat waves could kill.

In recent years he has been involved in studies that have tried to measure the challenge to the global harvest because of carbon dioxide accretion in the atmosphere as a consequence of fossil fuel combustion; the first years in which particular locations around the world could feel the impact of irreversible climate change; and then the proportion of humans at risk from heat extremes by the end of the century.

The latest study concludes that even if greenhouse gas emissions are dramatically reduced, most of the world would still be confronted by one hazard at a time: the worldwide average temperature rise of 1°C has already started to change climates and heighten climatic extremes.

And if humans go on burning fossil fuels in what has become notorious as the business-as-usual scenario, then almost everybody could face three hazards at the same time. In some coastal regions some people could be hit by six.

“The evidence of climate change impacting humanity is abundant, loud and clear … How many wake-up calls will it take to wake up?”

Higher atmospheric temperatures accelerate the evaporation of soil water. Normally dry places will be at risk of drought, heatwave and wildfire. Normally rainy places will face catastrophic downpour, and flood. Warmer ocean waters will evaporate at greater rates, so windspeed and rainfall from hurricanes will also increase. Sea level rise driven by water temperatures, and by glacial melting, will raise the risk of coastal flooding and storm surges.

Some of these impacts have already affected human health, bringing death, disease and mental illness. They have affected the supply of food on land and at sea; they have damaged electrical supplies, transportation, water and sewage infrastructure; they have damaged property and reduced labour productivity; they have triggered migration and sparked violence, and Dr Mora and his colleagues have now compiled a database of more than 3,000 documented examples.

“Greenhouse gas emissions pose a broad threat to humanity by simultaneously intensifying many hazards that have proved harmful in the past,” said Dr Mora.

“Further, we predict that by 2100 the number of hazards occurring concurrently will increase, making it even more difficult for people to cope.”

List of impacts

The latest study simply looks at all the recent climate impacts recorded and assessed and categorises them in a range of ways.

These include the 33% loss of grain to drought and fire in Russia in 2010; the loss of three-fourths of all livestock during drought in Kenya in 2000; drinking water shortages for 33 million people in China in 2001; the rise in waterborne infectious diseases after the 2010 Indus floods overwhelmed sewage treatment plants in Pakistan; the cumulative damage by flood and storm to millions of homes in China, Pakistan, Bangladesh, Indonesia, the US and France; and – because of melting ice – the forced relocation of Inuit villages in Alaska.

Heatwaves caused blackouts for 670 million people in India in 2012, and 35 million in Saudi Arabia in 2010. After Hurricane Andrew in 1992 hammered the US east coast, a total of 12 insurance companies went bust.

The next step, having assembled the possible kinds of impact, was to model the way they would be amplified and intensified under various scenarios for global warming. Wealth and economic power offer no great protection. New York can expect at worst by 2100 to face at least four hazards; Sydney and Los Angeles three; Mexico City four, and the Atlantic coast of Brazil five.

Present danger

“The collision of cumulative climate hazards is not something on the horizon, it is already here,” Dr Mora said. “Co-occurring and colliding climate hazards are already making headlines worldwide.

“Last year, for instance, Florida recorded extreme drought, record high temperatures, over 100 wildfires, and the strongest-ever recorded hurricane in its Panhandle: the category 4 Hurricane Michael.

“Likewise, California is currently experiencing ferocious wild fires and one of the longest droughts, plus extreme heatwaves this past summer.”

“The evidence of climate change impacting humanity is abundant, loud and clear”, said his co-author and colleague Daniele Spirandelli. “Clearly, the outstanding question is − how many wake-up calls will it take to wake up?” − Climate News Network

Climate impacts aren’t just potentially catastrophic: they could be simultaneous multiple disasters. US scientists have compiled a catalogue of calamity and a map of mayhem.

LONDON, 20 November, 2019 − By 2100, climate impacts will be felt by everyone and most people will experience at least three simultaneous hazards, inexorably made more hazardous by the build-up of greenhouse gases in the atmosphere.

And they could be the lucky ones: some people could be menaced by six different kinds of warming-related hazard simultaneously.

Camilo Mora of the University of Hawaii at Manoa and 22 colleagues report in Nature Climate Change that they read systematically through 3,280 peer-reviewed papers on the subject of climate change, and compiled a matrix of 467 ways in which 10 major climate hazards – floods, droughts, heat waves, fires and so on – and six aspects of human dependency (health, food, water, etc.) could affect humanity.

They did, they say, identify some positive or neutral effects, but the overwhelming majority of climate impacts would create problems for human communities and their economies.

Medical prospects

Dr Mora has established a reputation for thinking on the scale of global catalogue. Recently, the geographer and his fellow researchers looked at medical records and heat extremes and listed 27 different ways in which heat waves could kill.

In recent years he has been involved in studies that have tried to measure the challenge to the global harvest because of carbon dioxide accretion in the atmosphere as a consequence of fossil fuel combustion; the first years in which particular locations around the world could feel the impact of irreversible climate change; and then the proportion of humans at risk from heat extremes by the end of the century.

The latest study concludes that even if greenhouse gas emissions are dramatically reduced, most of the world would still be confronted by one hazard at a time: the worldwide average temperature rise of 1°C has already started to change climates and heighten climatic extremes.

And if humans go on burning fossil fuels in what has become notorious as the business-as-usual scenario, then almost everybody could face three hazards at the same time. In some coastal regions some people could be hit by six.

“The evidence of climate change impacting humanity is abundant, loud and clear … How many wake-up calls will it take to wake up?”

Higher atmospheric temperatures accelerate the evaporation of soil water. Normally dry places will be at risk of drought, heatwave and wildfire. Normally rainy places will face catastrophic downpour, and flood. Warmer ocean waters will evaporate at greater rates, so windspeed and rainfall from hurricanes will also increase. Sea level rise driven by water temperatures, and by glacial melting, will raise the risk of coastal flooding and storm surges.

Some of these impacts have already affected human health, bringing death, disease and mental illness. They have affected the supply of food on land and at sea; they have damaged electrical supplies, transportation, water and sewage infrastructure; they have damaged property and reduced labour productivity; they have triggered migration and sparked violence, and Dr Mora and his colleagues have now compiled a database of more than 3,000 documented examples.

“Greenhouse gas emissions pose a broad threat to humanity by simultaneously intensifying many hazards that have proved harmful in the past,” said Dr Mora.

“Further, we predict that by 2100 the number of hazards occurring concurrently will increase, making it even more difficult for people to cope.”

List of impacts

The latest study simply looks at all the recent climate impacts recorded and assessed and categorises them in a range of ways.

These include the 33% loss of grain to drought and fire in Russia in 2010; the loss of three-fourths of all livestock during drought in Kenya in 2000; drinking water shortages for 33 million people in China in 2001; the rise in waterborne infectious diseases after the 2010 Indus floods overwhelmed sewage treatment plants in Pakistan; the cumulative damage by flood and storm to millions of homes in China, Pakistan, Bangladesh, Indonesia, the US and France; and – because of melting ice – the forced relocation of Inuit villages in Alaska.

Heatwaves caused blackouts for 670 million people in India in 2012, and 35 million in Saudi Arabia in 2010. After Hurricane Andrew in 1992 hammered the US east coast, a total of 12 insurance companies went bust.

The next step, having assembled the possible kinds of impact, was to model the way they would be amplified and intensified under various scenarios for global warming. Wealth and economic power offer no great protection. New York can expect at worst by 2100 to face at least four hazards; Sydney and Los Angeles three; Mexico City four, and the Atlantic coast of Brazil five.

Present danger

“The collision of cumulative climate hazards is not something on the horizon, it is already here,” Dr Mora said. “Co-occurring and colliding climate hazards are already making headlines worldwide.

“Last year, for instance, Florida recorded extreme drought, record high temperatures, over 100 wildfires, and the strongest-ever recorded hurricane in its Panhandle: the category 4 Hurricane Michael.

“Likewise, California is currently experiencing ferocious wild fires and one of the longest droughts, plus extreme heatwaves this past summer.”

“The evidence of climate change impacting humanity is abundant, loud and clear”, said his co-author and colleague Daniele Spirandelli. “Clearly, the outstanding question is − how many wake-up calls will it take to wake up?” − Climate News Network

Iraq’s climate stresses are set to worsen

After years of repression, invasion and conflict, Iraq’s climate stresses now threaten new miseries, including more intense heat and dwindling rainfall.

LONDON, 12 November, 2018 − Iraq’s climate stresses are worsening, raising the prospect of a hotter, drier future for a country which has already seen widespread devastation.

It’s been invaded and bombed, had a third of its territory taken over by terrorist groups, hundreds of thousands have been killed and much of its infrastructure has been destroyed.

Now Iraq and its 39 million people are facing the hazards of climate change; a prolonged drought and soaring temperatures earlier this year ruined crops. Swathes of land in what was, in ancient times, one of the richest agricultural regions on Earth are drying up and turning into desert.

“Iraq is one of the Middle East’s most climate-vulnerable countries”

A recent report by the Expert Working Group on Climate-related Security Risks – made up of academics including members of the Stockholm International Peace Research Institute (SIPRI) – paints a stark picture of what’s happening in Iraq.

“Climate change is currently manifesting itself in prolonged heat waves, erratic precipitation, higher than average temperatures and increased disaster intensity”, says the report.

Its authors say that over the past summer Iraq suffered from its worst water shortage crisis for 80 years. They say flows of water in many rivers have decreased by up to 40% over recent decades.

The outlook is grim; the study says that due to climate change, average rainfall across the country is likely to decrease by 9% by mid-century, though the intensity of storms is set to increase. Temperatures in Iraq, which regularly reach more than 40°C in the summer months, are set to rise further – by an average of 2°C by 2050.

Livelihoods at risk

“Iraq is one of the Middle East’s most climate-vulnerable countries”, says the Working Group.

“The combination of its hydrological limitations, increasing temperatures and extreme weather events puts pressure on basic resources and undermines livelihood security for Iraq’s population.”

Oil revenues account for more than 80% of Iraq’s gross domestic product (GDP), but a majority of the workforce is involved in agriculture and has been hit hard by the drought and worsening climate conditions.

One of the regions of the country that has suffered most from shifting weather patterns and drought is the marshlands of the south, near the city of Basra.

Unique community

The marshlands, where the mighty Tigris and Euphrates rivers which flow through Iraq meet and divide into dozens of channels, formerly covered an area of more than 20,000 square kilometres and were once home to up to half a million people – widely referred to as Marsh Arabs – with a unique way of life.

In the early 1990s, Saddam Hussein, the country’s former ruler, dammed and drained the marshes after tribespeople in the area backed an uprising against his regime. After Saddam was toppled, locals tore down the dams and dykes and brought life back to the region.

Now, once again, the dense channels and waterways of southern Iraq are under threat.

Cross-border impacts

Reductions in rainfall and other climate-related events are only one part of what is a disaster unfolding in one of the most diverse and ecologically rich areas in the Middle East.

Misuse of upriver water resources by the Baghdad government and dams constructed across the Iraqi border, in Iran and Turkey, are severely reducing water levels in the Tigris and Euphrates.

As water levels have plummeted, salinity has increased dramatically, particularly in the south of the country, due to evaporation and saltwater intrusion from the Gulf. Often, because of salinity and pollution, there is little or no drinkable tap water in Basra, a city of more than 2 million.

During the drought last summer, thousands were hospitalised with water-borne diseases.

Corruption threat

Buffaloes, bird life and fish are dying. Reeds and other plant life are being destroyed.

Several people have been killed as protests have erupted over government ineptitude and the lack of basic infrastructure and jobs in what is Iraq’s most oil-rich province.

The Working Group’s report says generally poor governance is exacerbating an already precarious set of circumstances. Civil unrest and terrorism could further destabilise the country.

Widespread corruption is a serious problem. “This factor severely reduces the Iraqi government’s capacity to address security risks and stabilisation strategies, including those relating to climate change”, says the report. − Climate News Network

After years of repression, invasion and conflict, Iraq’s climate stresses now threaten new miseries, including more intense heat and dwindling rainfall.

LONDON, 12 November, 2018 − Iraq’s climate stresses are worsening, raising the prospect of a hotter, drier future for a country which has already seen widespread devastation.

It’s been invaded and bombed, had a third of its territory taken over by terrorist groups, hundreds of thousands have been killed and much of its infrastructure has been destroyed.

Now Iraq and its 39 million people are facing the hazards of climate change; a prolonged drought and soaring temperatures earlier this year ruined crops. Swathes of land in what was, in ancient times, one of the richest agricultural regions on Earth are drying up and turning into desert.

“Iraq is one of the Middle East’s most climate-vulnerable countries”

A recent report by the Expert Working Group on Climate-related Security Risks – made up of academics including members of the Stockholm International Peace Research Institute (SIPRI) – paints a stark picture of what’s happening in Iraq.

“Climate change is currently manifesting itself in prolonged heat waves, erratic precipitation, higher than average temperatures and increased disaster intensity”, says the report.

Its authors say that over the past summer Iraq suffered from its worst water shortage crisis for 80 years. They say flows of water in many rivers have decreased by up to 40% over recent decades.

The outlook is grim; the study says that due to climate change, average rainfall across the country is likely to decrease by 9% by mid-century, though the intensity of storms is set to increase. Temperatures in Iraq, which regularly reach more than 40°C in the summer months, are set to rise further – by an average of 2°C by 2050.

Livelihoods at risk

“Iraq is one of the Middle East’s most climate-vulnerable countries”, says the Working Group.

“The combination of its hydrological limitations, increasing temperatures and extreme weather events puts pressure on basic resources and undermines livelihood security for Iraq’s population.”

Oil revenues account for more than 80% of Iraq’s gross domestic product (GDP), but a majority of the workforce is involved in agriculture and has been hit hard by the drought and worsening climate conditions.

One of the regions of the country that has suffered most from shifting weather patterns and drought is the marshlands of the south, near the city of Basra.

Unique community

The marshlands, where the mighty Tigris and Euphrates rivers which flow through Iraq meet and divide into dozens of channels, formerly covered an area of more than 20,000 square kilometres and were once home to up to half a million people – widely referred to as Marsh Arabs – with a unique way of life.

In the early 1990s, Saddam Hussein, the country’s former ruler, dammed and drained the marshes after tribespeople in the area backed an uprising against his regime. After Saddam was toppled, locals tore down the dams and dykes and brought life back to the region.

Now, once again, the dense channels and waterways of southern Iraq are under threat.

Cross-border impacts

Reductions in rainfall and other climate-related events are only one part of what is a disaster unfolding in one of the most diverse and ecologically rich areas in the Middle East.

Misuse of upriver water resources by the Baghdad government and dams constructed across the Iraqi border, in Iran and Turkey, are severely reducing water levels in the Tigris and Euphrates.

As water levels have plummeted, salinity has increased dramatically, particularly in the south of the country, due to evaporation and saltwater intrusion from the Gulf. Often, because of salinity and pollution, there is little or no drinkable tap water in Basra, a city of more than 2 million.

During the drought last summer, thousands were hospitalised with water-borne diseases.

Corruption threat

Buffaloes, bird life and fish are dying. Reeds and other plant life are being destroyed.

Several people have been killed as protests have erupted over government ineptitude and the lack of basic infrastructure and jobs in what is Iraq’s most oil-rich province.

The Working Group’s report says generally poor governance is exacerbating an already precarious set of circumstances. Civil unrest and terrorism could further destabilise the country.

Widespread corruption is a serious problem. “This factor severely reduces the Iraqi government’s capacity to address security risks and stabilisation strategies, including those relating to climate change”, says the report. − Climate News Network

Warming raises threat of global famine repeat

famine

Global warming is increasing the chances of worldwide harvest failure on the scale of the tragic 19th-century drought and famine that claimed 50 million lives.

LONDON, 19 October, 2018 − Climate change driven by human-induced global warming could recreate the conditions for a re-run of one of the most tragic episodes in human history, the Great Drought and Global Famine of 1875 to 1878.

Those years were marked by widespread and prolonged droughts in Asia, Brazil and Africa, triggered by a coincidence of unusual conditions in the Pacific, Indian and North Atlantic Oceans.

The famine – made more lethal by the political constraints linked to 19th-century colonial domination of three continents – is now thought to have claimed up to 50 million lives.

And the message contained in new research published in the Journal of Climate is stark: what happened before could happen again.

One of the triggers was a cyclic blister of Pacific warming called El Niño, known to reverse global weather patterns, scorch rainforests and destabilise societies.

Another factor was a set of record warm temperatures in the North Atlantic that have been linked to drought in North Africa.

Linked to famine

A third was an unusually strong Indian Ocean dipole, a natural cyclic temperature change that has recently been linked to famine in the Horn of Africa.

The 1875-78 drought and famine began with the failure of the monsoon in India and China, leading to the most intense drought in the last 800 years. So many died in Shanxi province, China, that the population was restored to 1875 levels only in 1953.

The combination of record ocean temperatures and a very strong El Niño also intensified and prolonged droughts in Brazil and Australia. One million people are thought to have perished in the Nordeste province of Brazil.

In India, British colonial powers hoarded grain and exported it to England while continuing, the authors say, “to collect harsh taxes”.

Hunger, followed by typhoid and cholera, so weakened Asian and Africa societies that the French could colonise North Africa, and British forces could finally defeat the Zulu Nation in South Africa in 1879.

In effect, the authors say, the famine helped advance global inequalities and divide the globe into “first” and “third” worlds.

“Hydrological impacts intensified by global warming could again potentially undermine global food security”

Deepti Singh, a climate scientist at Washington State University Vancouver, has already identified an ominous weakening of the South Asian monsoon.

In her latest study, she and colleagues looked closely at historic records and what climate scientists call proxy evidence – tree ring measurements around the world, for instance – to identify the global climate conditions that must have driven the drought and famine.

“Climate conditions that caused the Great Drought and Global Famine arose from natural variability,” the researchers write. “And their recurrence – with hydrological impacts intensified by global warming – could again potentially undermine global food security.”

In fact, food security and the impact of climate change has become a recurring research theme.

Scientists have repeatedly warned that human-induced global warming can only intensify drought, not just in those already vulnerable regions but also in the fertile and flourishing farmlands of the US and the teeming rainforests of the Amazon.

Catastrophic drought

Studies of the deep past have identified catastrophic, prolonged drought long ago in the eastern Mediterranean, birthplace of agriculture and again suffering from recent sustained drought.

More recent research has confirmed that heat extremes and drought could seriously afflict grain yields in Europe and crop yields worldwide, while drought and monsoon failure present an immediate threat to food supplies in south-east Asia.

Agriculture anywhere is always a gamble on the familiar pattern of climate. Farmers tend to go on planting crops that do well, and some farmers, somewhere, will always experience crop failure.

Multiple disruption

However, the latest study confirms that any change in the global forces that drive weather – and these include air and ocean temperatures – could also make more probable a kind of multiple disruption of the normal.

And that, the researchers suggest, could bring back the triple hazard of disastrous change in all three oceans at the same time. Widespread, sustained drought could become even more severe.

In the last 150 years, the world has changed, politically and economically, but the researchers say that “such extreme events would still lead to severe shocks to the global food system, with local food insecurity in vulnerable countries potentially amplified by today’s highly-connected global food trade network”.

And they argue that better understanding of how the machinery of climate works to produce such devastating drought “should translate into improved prediction of the consequences of any such future event and allow effective management of the resulting food crises, so that the next Great Drought does not trigger another Great Famine.” – Climate News Network

Global warming is increasing the chances of worldwide harvest failure on the scale of the tragic 19th-century drought and famine that claimed 50 million lives.

LONDON, 19 October, 2018 − Climate change driven by human-induced global warming could recreate the conditions for a re-run of one of the most tragic episodes in human history, the Great Drought and Global Famine of 1875 to 1878.

Those years were marked by widespread and prolonged droughts in Asia, Brazil and Africa, triggered by a coincidence of unusual conditions in the Pacific, Indian and North Atlantic Oceans.

The famine – made more lethal by the political constraints linked to 19th-century colonial domination of three continents – is now thought to have claimed up to 50 million lives.

And the message contained in new research published in the Journal of Climate is stark: what happened before could happen again.

One of the triggers was a cyclic blister of Pacific warming called El Niño, known to reverse global weather patterns, scorch rainforests and destabilise societies.

Another factor was a set of record warm temperatures in the North Atlantic that have been linked to drought in North Africa.

Linked to famine

A third was an unusually strong Indian Ocean dipole, a natural cyclic temperature change that has recently been linked to famine in the Horn of Africa.

The 1875-78 drought and famine began with the failure of the monsoon in India and China, leading to the most intense drought in the last 800 years. So many died in Shanxi province, China, that the population was restored to 1875 levels only in 1953.

The combination of record ocean temperatures and a very strong El Niño also intensified and prolonged droughts in Brazil and Australia. One million people are thought to have perished in the Nordeste province of Brazil.

In India, British colonial powers hoarded grain and exported it to England while continuing, the authors say, “to collect harsh taxes”.

Hunger, followed by typhoid and cholera, so weakened Asian and Africa societies that the French could colonise North Africa, and British forces could finally defeat the Zulu Nation in South Africa in 1879.

In effect, the authors say, the famine helped advance global inequalities and divide the globe into “first” and “third” worlds.

“Hydrological impacts intensified by global warming could again potentially undermine global food security”

Deepti Singh, a climate scientist at Washington State University Vancouver, has already identified an ominous weakening of the South Asian monsoon.

In her latest study, she and colleagues looked closely at historic records and what climate scientists call proxy evidence – tree ring measurements around the world, for instance – to identify the global climate conditions that must have driven the drought and famine.

“Climate conditions that caused the Great Drought and Global Famine arose from natural variability,” the researchers write. “And their recurrence – with hydrological impacts intensified by global warming – could again potentially undermine global food security.”

In fact, food security and the impact of climate change has become a recurring research theme.

Scientists have repeatedly warned that human-induced global warming can only intensify drought, not just in those already vulnerable regions but also in the fertile and flourishing farmlands of the US and the teeming rainforests of the Amazon.

Catastrophic drought

Studies of the deep past have identified catastrophic, prolonged drought long ago in the eastern Mediterranean, birthplace of agriculture and again suffering from recent sustained drought.

More recent research has confirmed that heat extremes and drought could seriously afflict grain yields in Europe and crop yields worldwide, while drought and monsoon failure present an immediate threat to food supplies in south-east Asia.

Agriculture anywhere is always a gamble on the familiar pattern of climate. Farmers tend to go on planting crops that do well, and some farmers, somewhere, will always experience crop failure.

Multiple disruption

However, the latest study confirms that any change in the global forces that drive weather – and these include air and ocean temperatures – could also make more probable a kind of multiple disruption of the normal.

And that, the researchers suggest, could bring back the triple hazard of disastrous change in all three oceans at the same time. Widespread, sustained drought could become even more severe.

In the last 150 years, the world has changed, politically and economically, but the researchers say that “such extreme events would still lead to severe shocks to the global food system, with local food insecurity in vulnerable countries potentially amplified by today’s highly-connected global food trade network”.

And they argue that better understanding of how the machinery of climate works to produce such devastating drought “should translate into improved prediction of the consequences of any such future event and allow effective management of the resulting food crises, so that the next Great Drought does not trigger another Great Famine.” – Climate News Network

Fire and drought threaten China and Europe

Even if nations do limit global warming, fire and drought will remain threats, ravaging more harvests in China and setting more of Europe ablaze.

LONDON, 9 October, 2018 – The most limited rise in global temperatures, never mind higher ones, is going to exact a price through fire and drought. Even assuming the world keeps to its Paris promise to contain average planetary temperature increases to “well below 2°C” by 2100, drought conditions in China will intensify ten or 20-fold, according to new research.

And even if this warming, driven by ever increasing emissions of greenhouse gases from burning coal, oil and gas, is held to the implicit ambition of no more than 1.5°C above the average for most of human history, the area charred by wildfires each summer in Europe could increase by 40%, according to a separate study.

If the temperatures continue to rise to as much as 3°C by the century’s end, the area covered by charred foliage and smoking tree trunks could rise by 100%.

The temperature targets are important because 195 nations agreed in 2015 at a UN conference in Paris to limit greenhouse gas emissions and hold planetary average temperatures to if possible 1.5°C and certainly no more than 2°C.

3°C in prospect

In the last century or so, increasing ratios of carbon dioxide in the planet’s atmosphere have lifted average temperatures by about 1°C already, and although almost all nations have announced plans to switch to solar and wind power for future energy sources, and to restore the forests that absorb carbon, the world still seems on course for a rise to 3°C by the end of the century.

Politicians and climate sceptics argue that action to contain global warming will be expensive. But over and over again, climate science research continues to demonstrate that inaction could be even more expensive.

China is now the world’s largest emitter of greenhouse gases. Scientists from China, Poland and Germany report in the Proceedings of the National Academy of Sciences that they used computer simulations and a range of climate change forecasts to model what could happen to rainfall and vegetation in China over the next 80 years, and then tried to calculate the effect on China’s developing economy.

Between 1949 and 2017, drought affected crops over an area of more than 2 million square kilometres – this is one sixth of the country’s arable land. And between 1984 and 2017, direct economic losses reached more than $7bn a year, at 2015 prices.

“Limiting global warming to 1.5°C can strongly reduce the increase of burned area”

If the temperature stabilises at a 1.5°C increase, losses compared to the period 1986-2005 will increase tenfold. Compared to the immediate past of 2006-2015, the study estimates that losses will still rise threefold. And should the temperature go beyond 1.5°C to 2°C, average drought loss could double again.

Studies such as these simply match what has happened in the past with what could happen in the future – always provided that things continue as they seem to be proceeding now. The studies can deliver only very broad-brush outlines of the shapes of things to come.

Higher average temperatures will mean ever more pronounced extremes of drought and rainfall, and a study earlier this year warned that, in China alone, catastrophic flooding as a consequence of climate change could cost the country $380bn over the next 20 years.

Europe, too, the same study argued, would suffer significant losses as a consequence of climate change. Another such study in 2017 estimated that climate change – and the attendant hazards of flood, drought, wildfire and heatwaves – could threaten 350 million Europeans every year.

Consistent pattern

Forest and scrub fires char on average about 4,500 square kilometres of Mediterranean Europe every year: in 2017, there were damaging blazes in France, Italy, Portugal and Spain, with human casualties and extensive ecological and economic losses.

Now new research led by Spanish scientists and reported in the journal Nature Communications uses computer simulations and available data to take a look at the fires next time, as the temperatures rise.

The authors warn that even though there are large uncertainties in such projections, there is also a consistent pattern: the higher the temperatures, the more sustained the droughts, and the larger the areas that will be incinerated.

They do offer a palliative solution, though. “Limiting global warming to 1.5°C can strongly reduce the increase of burned area,” they say. – Climate News Network

Even if nations do limit global warming, fire and drought will remain threats, ravaging more harvests in China and setting more of Europe ablaze.

LONDON, 9 October, 2018 – The most limited rise in global temperatures, never mind higher ones, is going to exact a price through fire and drought. Even assuming the world keeps to its Paris promise to contain average planetary temperature increases to “well below 2°C” by 2100, drought conditions in China will intensify ten or 20-fold, according to new research.

And even if this warming, driven by ever increasing emissions of greenhouse gases from burning coal, oil and gas, is held to the implicit ambition of no more than 1.5°C above the average for most of human history, the area charred by wildfires each summer in Europe could increase by 40%, according to a separate study.

If the temperatures continue to rise to as much as 3°C by the century’s end, the area covered by charred foliage and smoking tree trunks could rise by 100%.

The temperature targets are important because 195 nations agreed in 2015 at a UN conference in Paris to limit greenhouse gas emissions and hold planetary average temperatures to if possible 1.5°C and certainly no more than 2°C.

3°C in prospect

In the last century or so, increasing ratios of carbon dioxide in the planet’s atmosphere have lifted average temperatures by about 1°C already, and although almost all nations have announced plans to switch to solar and wind power for future energy sources, and to restore the forests that absorb carbon, the world still seems on course for a rise to 3°C by the end of the century.

Politicians and climate sceptics argue that action to contain global warming will be expensive. But over and over again, climate science research continues to demonstrate that inaction could be even more expensive.

China is now the world’s largest emitter of greenhouse gases. Scientists from China, Poland and Germany report in the Proceedings of the National Academy of Sciences that they used computer simulations and a range of climate change forecasts to model what could happen to rainfall and vegetation in China over the next 80 years, and then tried to calculate the effect on China’s developing economy.

Between 1949 and 2017, drought affected crops over an area of more than 2 million square kilometres – this is one sixth of the country’s arable land. And between 1984 and 2017, direct economic losses reached more than $7bn a year, at 2015 prices.

“Limiting global warming to 1.5°C can strongly reduce the increase of burned area”

If the temperature stabilises at a 1.5°C increase, losses compared to the period 1986-2005 will increase tenfold. Compared to the immediate past of 2006-2015, the study estimates that losses will still rise threefold. And should the temperature go beyond 1.5°C to 2°C, average drought loss could double again.

Studies such as these simply match what has happened in the past with what could happen in the future – always provided that things continue as they seem to be proceeding now. The studies can deliver only very broad-brush outlines of the shapes of things to come.

Higher average temperatures will mean ever more pronounced extremes of drought and rainfall, and a study earlier this year warned that, in China alone, catastrophic flooding as a consequence of climate change could cost the country $380bn over the next 20 years.

Europe, too, the same study argued, would suffer significant losses as a consequence of climate change. Another such study in 2017 estimated that climate change – and the attendant hazards of flood, drought, wildfire and heatwaves – could threaten 350 million Europeans every year.

Consistent pattern

Forest and scrub fires char on average about 4,500 square kilometres of Mediterranean Europe every year: in 2017, there were damaging blazes in France, Italy, Portugal and Spain, with human casualties and extensive ecological and economic losses.

Now new research led by Spanish scientists and reported in the journal Nature Communications uses computer simulations and available data to take a look at the fires next time, as the temperatures rise.

The authors warn that even though there are large uncertainties in such projections, there is also a consistent pattern: the higher the temperatures, the more sustained the droughts, and the larger the areas that will be incinerated.

They do offer a palliative solution, though. “Limiting global warming to 1.5°C can strongly reduce the increase of burned area,” they say. – Climate News Network

Warming climate leaves its varied marks

The warming climate is changing the globe: mountain species climb higher, valley floors sink and animal numbers fall, while their living space shrinks.

LONDON, 28 September, 2018 – The Earth’s warming climate is already reshaping the planet. A new study confirms that plants and animals unique to the mountains are climbing ever higher to survive.

A second research team has taken a closer look at the valley floors of Central California to find that one of them is now, thanks to drought conditions, sinking by up to half a metre a year.

In central and eastern Europe, German scientists have found that the Danube – on which people used to skate every winter – has frozen only a handful of times in the last 70 years.

And far to the south, French scientists report that one of the world’s largest colonies of king penguins has dwindled by 88% since 1982.

In all cases, researchers identify a possible environmental cause: and in all cases the changes could be linked to global warming. In three instances out of four, climate change has already been implicated by other studies.

“The scientists calculate that for every 1°C rise in temperature, species are moving an average of 100 metres uphill”

Years ago, Swiss scientists observed a steady uphill migration of alpine butterflies and birds; while US scientists have charted change in mountain flora in the Rockies and Danish scientists revisited an Andean mountain first explored by the great Alexander von Humboldt to find that the plants he recorded had climbed 500 metres in 210 years.

Now Canadian scientists report in the journal Global Ecology and Biogeography that they set themselves the challenge of the global picture: they reviewed studies of elevation shifts in 975 species of plant, insect and animal.

In the French Pyrenees, the mountain burnet butterfly has shifted uphill by 430 metres and surrendered 79% of its range. In the Himalayas, where temperatures have risen by 2.2°C in 150 years, one meadow flower has migrated more than 600 metres and lost 28% of its preferred habitat. In Nevada’s Ruby Mountains, the northern pocket gopher has responded to a warming of 1.1°C in 80 years by climbing higher and surrendering 70% of its living room.

Altogether, the scientists calculate that for every 1°C rise in temperature, species are moving an average of 100 metres uphill.

In the mountains of California, the peaks are getting ever higher because the reduced mass of snowfall no longer depresses the rock.

Sinking feeling

Paradoxically, thanks to the combination of sustained drought and relentless abstraction of groundwater for agriculture, things are going downhill in the San Joaquin valley of California,, according to scientists from Cornell University who report in the journal Science Advances. The valley is home to 75% of California’s irrigated farmland. It supplies 8% of US agricultural output and it has a long record of slow subsidence.

The Cornell scientists report that between 1962 and 2011, the valley lost groundwater at the rate of 1.85 cubic kilometres a year. Between 2012 and 2016, during the state’s worst-ever drought, the same basin lost 40 cubic kilometres of groundwater, and the ground fell at 50 cms a year, except for a slowdown in subsidence during the heavy rains of 2017. The previous rate of subsidence has resumed.

The Danube Commission has kept records since 1836 of the behaviour of Europe’s second largest river as it flows from the Alps to the Black Sea. Researchers from Germany’s Alfred Wegener Institute write in the journal Scientific Reports that archivists reported ice cover almost every year, ice thick enough to bear skaters.

But between 1951 and 2016, the river froze only 10 times. Although more people live in Europe than ever before, and discharge more outflow into the Danube basin, the researchers identify global warming as a substantial cause: winter temperatures have risen and are now more than 1.0°C warmer than in the first half of the 20th century.

Problems for penguins

And rising temperatures might be at the heart of the crisis for king penguins on the Iles Crozet archipelago in Antarctica: French scientists report in the journal Antarctic Science that in 1982 the colony was home to 500,000 breeding pairs and two million specimens of Aptenodytes patagonicus.

Now the colony has shrunk, and vegetation cover has expanded. The loss might be linked to lack of food, or a major natural warming event such as El Nino, or to disease such as avian cholera.

But global warming and climate change have already been linked to alarms over the king penguin elsewhere, and to the possible fate of the emperor penguin.

The research is based on aerial imagery and satellite studies, and on-the-ground research is still needed to explain quite why a colony which once supported 500,000 breeding pairs should now number only 60,000 penguin couples.

“The cause of the massive decline of the colony remains a mystery, and needs to be resolved,” the French scientists say. – Climate News Network

The warming climate is changing the globe: mountain species climb higher, valley floors sink and animal numbers fall, while their living space shrinks.

LONDON, 28 September, 2018 – The Earth’s warming climate is already reshaping the planet. A new study confirms that plants and animals unique to the mountains are climbing ever higher to survive.

A second research team has taken a closer look at the valley floors of Central California to find that one of them is now, thanks to drought conditions, sinking by up to half a metre a year.

In central and eastern Europe, German scientists have found that the Danube – on which people used to skate every winter – has frozen only a handful of times in the last 70 years.

And far to the south, French scientists report that one of the world’s largest colonies of king penguins has dwindled by 88% since 1982.

In all cases, researchers identify a possible environmental cause: and in all cases the changes could be linked to global warming. In three instances out of four, climate change has already been implicated by other studies.

“The scientists calculate that for every 1°C rise in temperature, species are moving an average of 100 metres uphill”

Years ago, Swiss scientists observed a steady uphill migration of alpine butterflies and birds; while US scientists have charted change in mountain flora in the Rockies and Danish scientists revisited an Andean mountain first explored by the great Alexander von Humboldt to find that the plants he recorded had climbed 500 metres in 210 years.

Now Canadian scientists report in the journal Global Ecology and Biogeography that they set themselves the challenge of the global picture: they reviewed studies of elevation shifts in 975 species of plant, insect and animal.

In the French Pyrenees, the mountain burnet butterfly has shifted uphill by 430 metres and surrendered 79% of its range. In the Himalayas, where temperatures have risen by 2.2°C in 150 years, one meadow flower has migrated more than 600 metres and lost 28% of its preferred habitat. In Nevada’s Ruby Mountains, the northern pocket gopher has responded to a warming of 1.1°C in 80 years by climbing higher and surrendering 70% of its living room.

Altogether, the scientists calculate that for every 1°C rise in temperature, species are moving an average of 100 metres uphill.

In the mountains of California, the peaks are getting ever higher because the reduced mass of snowfall no longer depresses the rock.

Sinking feeling

Paradoxically, thanks to the combination of sustained drought and relentless abstraction of groundwater for agriculture, things are going downhill in the San Joaquin valley of California,, according to scientists from Cornell University who report in the journal Science Advances. The valley is home to 75% of California’s irrigated farmland. It supplies 8% of US agricultural output and it has a long record of slow subsidence.

The Cornell scientists report that between 1962 and 2011, the valley lost groundwater at the rate of 1.85 cubic kilometres a year. Between 2012 and 2016, during the state’s worst-ever drought, the same basin lost 40 cubic kilometres of groundwater, and the ground fell at 50 cms a year, except for a slowdown in subsidence during the heavy rains of 2017. The previous rate of subsidence has resumed.

The Danube Commission has kept records since 1836 of the behaviour of Europe’s second largest river as it flows from the Alps to the Black Sea. Researchers from Germany’s Alfred Wegener Institute write in the journal Scientific Reports that archivists reported ice cover almost every year, ice thick enough to bear skaters.

But between 1951 and 2016, the river froze only 10 times. Although more people live in Europe than ever before, and discharge more outflow into the Danube basin, the researchers identify global warming as a substantial cause: winter temperatures have risen and are now more than 1.0°C warmer than in the first half of the 20th century.

Problems for penguins

And rising temperatures might be at the heart of the crisis for king penguins on the Iles Crozet archipelago in Antarctica: French scientists report in the journal Antarctic Science that in 1982 the colony was home to 500,000 breeding pairs and two million specimens of Aptenodytes patagonicus.

Now the colony has shrunk, and vegetation cover has expanded. The loss might be linked to lack of food, or a major natural warming event such as El Nino, or to disease such as avian cholera.

But global warming and climate change have already been linked to alarms over the king penguin elsewhere, and to the possible fate of the emperor penguin.

The research is based on aerial imagery and satellite studies, and on-the-ground research is still needed to explain quite why a colony which once supported 500,000 breeding pairs should now number only 60,000 penguin couples.

“The cause of the massive decline of the colony remains a mystery, and needs to be resolved,” the French scientists say. – Climate News Network

Hotter planet faces more killer heat

The Earth can expect more killer heat, from lethal heat waves and more intense temperatures claiming more lives. Wildfires, too, will become more polluting.

LONDON, 25 September, 2018 – Once again, researchers have confirmed that limiting global warming will save lives by reducing the impact of killer heat.

An international team has checked predictions for heat-related deaths against some of the global average temperatures likely later this century, to issue this warning: it will be a safer world if temperatures creep up by only 1.5°C over historic levels. Fewer people will die in the ever more intense heat extremes that will go with average global temperature rises.

And a second, separate study of the impact of forest, bush and wildfires on human health has warned that – in the US alone – deaths linked to smoke could more than double, to perhaps 40,000 a year.

The world has already warmed by around 1°C in the last century: the limit of “well below 2°C” set by 195 nations when they met in Paris in 2015 looks increasingly close.

Scientists from Britain, Europe, Australia, the US, Brazil, Chile and China report in the journal Climatic Change that they looked at records for temperature-related deaths from 451 places in 23 countries and then projected likely deaths as global average temperatures rose by 1.5°C, and then up to 3°C and 4°C.

“Large parts of the world could experience a dramatic increase in excess mortality due to heat. This would not be balanced by decreases in cold-related deaths”

They found that at the higher forecasts, hazards rose steeply: in the worst instances, by almost 9%.

Alarm about the impact of heat waves on human health is not new: in the last few years researchers have warned that by 2100, around 75% of humanity will be at some risk of death by heat extremes. Another group has measured suicide statistics and seen a rise with temperature extremes.

A third group has focused on the double hazard of ever greater heat and humidity, and a fourth has identified at least 27 different ways in which heat waves can claim lives.

So the latest study is separate confirmation, this time by medical scientists who need to know what to expect as the thermometer rises.

Limiting fatalities

“Our projections suggest that large increases in temperature-related deaths could be limited in most regions if warming was kept below 2°C,”explains Ana Maria Vicedo-Cabrera, who led the study.

“Under extreme changes in climate, large parts of the world could experience a dramatic increase in excess mortality due to heat. This would not be balanced by decreases in cold-related deaths. Efforts to limit the increase in global temperature to below 1.5°C could provide additional benefits in tropical or arid regions, including the most populous and often poorest countries.”

With ever higher temperatures there will be ever more prolonged droughts, and inevitably greater risk of wildfire, and particularly in the US.

Right now, wildfires in the US claim an estimated 15,000 lives a year, chiefly through smoke inhalation that can worsen chronic pulmonary conditions, or hasten death in people with heart conditions.

By 2100, scientists report in the American Geophysical Union journal Geohealth, the death count in the contiguous US could reach 40,000 a year.

Particulate menace

The study recognizes that wildfire hazard has a number of causes and that climate change is only part of the story. But in the first six months of 2018, the US government’s own National Oceanic and Atmospheric Administration recorded 37,718 fires that burned almost 20,000 square kilometres.

In 2017, wildfire fighting cost the US Forest Service a record $2.4bn. And each fire hurled high levels of particulate matter – soot and other detritus – into the atmosphere, and into a nation’s eyes and lungs.

“We know from our own research and many, many other groups that smoke has negative impacts on human health,” said Jeff Pierce, an atmospheric scientist at the University of Colorado, and one of the authors.

“With the knowledge that fires have been increasing in parts of the US, we wanted to look at how bad this might get.” – Climate News Network

The Earth can expect more killer heat, from lethal heat waves and more intense temperatures claiming more lives. Wildfires, too, will become more polluting.

LONDON, 25 September, 2018 – Once again, researchers have confirmed that limiting global warming will save lives by reducing the impact of killer heat.

An international team has checked predictions for heat-related deaths against some of the global average temperatures likely later this century, to issue this warning: it will be a safer world if temperatures creep up by only 1.5°C over historic levels. Fewer people will die in the ever more intense heat extremes that will go with average global temperature rises.

And a second, separate study of the impact of forest, bush and wildfires on human health has warned that – in the US alone – deaths linked to smoke could more than double, to perhaps 40,000 a year.

The world has already warmed by around 1°C in the last century: the limit of “well below 2°C” set by 195 nations when they met in Paris in 2015 looks increasingly close.

Scientists from Britain, Europe, Australia, the US, Brazil, Chile and China report in the journal Climatic Change that they looked at records for temperature-related deaths from 451 places in 23 countries and then projected likely deaths as global average temperatures rose by 1.5°C, and then up to 3°C and 4°C.

“Large parts of the world could experience a dramatic increase in excess mortality due to heat. This would not be balanced by decreases in cold-related deaths”

They found that at the higher forecasts, hazards rose steeply: in the worst instances, by almost 9%.

Alarm about the impact of heat waves on human health is not new: in the last few years researchers have warned that by 2100, around 75% of humanity will be at some risk of death by heat extremes. Another group has measured suicide statistics and seen a rise with temperature extremes.

A third group has focused on the double hazard of ever greater heat and humidity, and a fourth has identified at least 27 different ways in which heat waves can claim lives.

So the latest study is separate confirmation, this time by medical scientists who need to know what to expect as the thermometer rises.

Limiting fatalities

“Our projections suggest that large increases in temperature-related deaths could be limited in most regions if warming was kept below 2°C,”explains Ana Maria Vicedo-Cabrera, who led the study.

“Under extreme changes in climate, large parts of the world could experience a dramatic increase in excess mortality due to heat. This would not be balanced by decreases in cold-related deaths. Efforts to limit the increase in global temperature to below 1.5°C could provide additional benefits in tropical or arid regions, including the most populous and often poorest countries.”

With ever higher temperatures there will be ever more prolonged droughts, and inevitably greater risk of wildfire, and particularly in the US.

Right now, wildfires in the US claim an estimated 15,000 lives a year, chiefly through smoke inhalation that can worsen chronic pulmonary conditions, or hasten death in people with heart conditions.

By 2100, scientists report in the American Geophysical Union journal Geohealth, the death count in the contiguous US could reach 40,000 a year.

Particulate menace

The study recognizes that wildfire hazard has a number of causes and that climate change is only part of the story. But in the first six months of 2018, the US government’s own National Oceanic and Atmospheric Administration recorded 37,718 fires that burned almost 20,000 square kilometres.

In 2017, wildfire fighting cost the US Forest Service a record $2.4bn. And each fire hurled high levels of particulate matter – soot and other detritus – into the atmosphere, and into a nation’s eyes and lungs.

“We know from our own research and many, many other groups that smoke has negative impacts on human health,” said Jeff Pierce, an atmospheric scientist at the University of Colorado, and one of the authors.

“With the knowledge that fires have been increasing in parts of the US, we wanted to look at how bad this might get.” – Climate News Network