Tag Archives: Australia

Extreme drought and fire risk may double by 2060

Climate change may soon double the impact of extreme drought and fire. And it’s a two-way traffic.

LONDON, 25 January, 2021 − As climate change threatens a doubling of the impact of extreme drought and fire within a generation, researchers are uncovering the influence of human activity on both these growing risks.

One study has found that human numbers exposed to the hazard of extreme drought are likely to double in the decades to come, as global heating bakes away the groundwater and limits annual snowfall.

Another team of researchers says the risks of extreme wildfire could also rise twofold in the next 40 years in the Mediterranean, southern Africa, eastern North America and the Amazon. In those places already severely scorched by frequent fire − western North America, equatorial Africa, south-east Asia and Australia − hazards could rise by 50%.

And a third, separate study warns that global temperature rise will shift the patterns of rainfall around the tropics − with the consequent risks to tropical crop harvests and to equatorial ecosystems such as rainforest and savannah.

All three studies are reminders of the intricacies of the planetary climate system and the impact of human action in the last hundred years.

“Areas of the southern hemisphere, where water scarcity is already a problem, will be disproportionately affected. We predict this will affect food security and escalate human migration and conflict.”

An international research team reports in the journal Nature Climate Change that it looked at the simple problem of global terrestrial water storage: all the moisture in the canopies of forest trees, in the mountain snows and ice, in the lakes, rivers, wetlands, and in the soil itself.

This wealth of stored water is a big player in the patterns of global flooding and drought in the monsoon climates and the arid lands alike. But, the researchers say, there has so far been no study of the potential impact of global climate change on global terrestrial water storage overall.

So researchers from the US, China, Japan and Europe began modelling tomorrow’s world. And they found that, while 3% of the planet’s people were vulnerable to extreme drought in the timespan from 1976 to 2005, later in the century this proportion could increase to 7% or even 8%.

“More and more people will suffer from extreme droughts if a medium-to-high level of global warming continues and water management is maintained in its present state,” warned Yadu Pokhrel, an engineer at Michigan State University, who led the research.

“Areas of the southern hemisphere, where water scarcity is already a problem, will be disproportionately affected. We predict this increase in water scarcity will affect food security and escalate human migration and conflict.”

Fire chances increased

Australia is a southern hemisphere country that knows about water scarcity: its wildfires in 2019 broke all records and sent a vast cloud of smoke to an altitude of 35 kms.

And, on the evidence of a new study in the journal Nature Communications, it won’t be the last such extreme event. Californian scientists, struck by the scale and intensity of Californian wildfires in 2017 and 2018, report that they took a closer look at the way greenhouse gas emissions and human land use change have played into the risks of extreme fire weather.

The simple act of setting forests afire to clear land for farm use has amplified the risk of extreme blazes in the Amazon and North America by 30% in the last century. Fires create aerosols that could, by absorbing sunlight, help cool the terrain beneath them − in some zones. But they could also affect rainfall levels and raise the chances of fire. The nature of such impacts varies from place to place.

“South-east Asia relies on the monsoon, but aerosols cause so much cooling on land that they can actually suppress a monsoon,” said Danielle Touma of the University of California at Santa Barbara. “It’s not just whether you have aerosols or not, it’s the way the regional climate interacts with aerosols.”

Aerosols − with other forces − cannot just suppress a monsoon, they can shift rain patterns permanently. The tropics, too, have begun to feel the heat of the moment.

Drought stress rises

The footprint of extreme drought and fire is massive. Californian researchers report in Nature Climate Change that, across two thirds of the globe, the tropical rainbelt is likely to shift north over eastern Africa and the Indian Ocean to cause more drought stress in south-eastern Africa and Madagascar and intensified flooding in south Asia.

In the western hemisphere, however, as the Gulf Stream current and the North Atlantic deep water formation weaken, the rain belt could move south to bring greater drought stress to Central America.

And once again, climate change driven by global heating is at work with other human influences to alter what had for most of human history been a stable pattern of climate.

“In Asia, projected reductions in aerosol emissions, glacier melting in the Himalayas and loss of snow cover in northern areas brought on by climate change will cause the atmosphere to heat up faster than in other regions,” said James Randerson of the University of California, Irvine, one of the authors.

“We know the rainbelt shifts towards this heating, and that its northward movement in the eastern hemisphere is consistent with these expected impacts of climate change.” − Climate News Network

Climate change may soon double the impact of extreme drought and fire. And it’s a two-way traffic.

LONDON, 25 January, 2021 − As climate change threatens a doubling of the impact of extreme drought and fire within a generation, researchers are uncovering the influence of human activity on both these growing risks.

One study has found that human numbers exposed to the hazard of extreme drought are likely to double in the decades to come, as global heating bakes away the groundwater and limits annual snowfall.

Another team of researchers says the risks of extreme wildfire could also rise twofold in the next 40 years in the Mediterranean, southern Africa, eastern North America and the Amazon. In those places already severely scorched by frequent fire − western North America, equatorial Africa, south-east Asia and Australia − hazards could rise by 50%.

And a third, separate study warns that global temperature rise will shift the patterns of rainfall around the tropics − with the consequent risks to tropical crop harvests and to equatorial ecosystems such as rainforest and savannah.

All three studies are reminders of the intricacies of the planetary climate system and the impact of human action in the last hundred years.

“Areas of the southern hemisphere, where water scarcity is already a problem, will be disproportionately affected. We predict this will affect food security and escalate human migration and conflict.”

An international research team reports in the journal Nature Climate Change that it looked at the simple problem of global terrestrial water storage: all the moisture in the canopies of forest trees, in the mountain snows and ice, in the lakes, rivers, wetlands, and in the soil itself.

This wealth of stored water is a big player in the patterns of global flooding and drought in the monsoon climates and the arid lands alike. But, the researchers say, there has so far been no study of the potential impact of global climate change on global terrestrial water storage overall.

So researchers from the US, China, Japan and Europe began modelling tomorrow’s world. And they found that, while 3% of the planet’s people were vulnerable to extreme drought in the timespan from 1976 to 2005, later in the century this proportion could increase to 7% or even 8%.

“More and more people will suffer from extreme droughts if a medium-to-high level of global warming continues and water management is maintained in its present state,” warned Yadu Pokhrel, an engineer at Michigan State University, who led the research.

“Areas of the southern hemisphere, where water scarcity is already a problem, will be disproportionately affected. We predict this increase in water scarcity will affect food security and escalate human migration and conflict.”

Fire chances increased

Australia is a southern hemisphere country that knows about water scarcity: its wildfires in 2019 broke all records and sent a vast cloud of smoke to an altitude of 35 kms.

And, on the evidence of a new study in the journal Nature Communications, it won’t be the last such extreme event. Californian scientists, struck by the scale and intensity of Californian wildfires in 2017 and 2018, report that they took a closer look at the way greenhouse gas emissions and human land use change have played into the risks of extreme fire weather.

The simple act of setting forests afire to clear land for farm use has amplified the risk of extreme blazes in the Amazon and North America by 30% in the last century. Fires create aerosols that could, by absorbing sunlight, help cool the terrain beneath them − in some zones. But they could also affect rainfall levels and raise the chances of fire. The nature of such impacts varies from place to place.

“South-east Asia relies on the monsoon, but aerosols cause so much cooling on land that they can actually suppress a monsoon,” said Danielle Touma of the University of California at Santa Barbara. “It’s not just whether you have aerosols or not, it’s the way the regional climate interacts with aerosols.”

Aerosols − with other forces − cannot just suppress a monsoon, they can shift rain patterns permanently. The tropics, too, have begun to feel the heat of the moment.

Drought stress rises

The footprint of extreme drought and fire is massive. Californian researchers report in Nature Climate Change that, across two thirds of the globe, the tropical rainbelt is likely to shift north over eastern Africa and the Indian Ocean to cause more drought stress in south-eastern Africa and Madagascar and intensified flooding in south Asia.

In the western hemisphere, however, as the Gulf Stream current and the North Atlantic deep water formation weaken, the rain belt could move south to bring greater drought stress to Central America.

And once again, climate change driven by global heating is at work with other human influences to alter what had for most of human history been a stable pattern of climate.

“In Asia, projected reductions in aerosol emissions, glacier melting in the Himalayas and loss of snow cover in northern areas brought on by climate change will cause the atmosphere to heat up faster than in other regions,” said James Randerson of the University of California, Irvine, one of the authors.

“We know the rainbelt shifts towards this heating, and that its northward movement in the eastern hemisphere is consistent with these expected impacts of climate change.” − Climate News Network

Climate chaos batters global insurance industry

The climate crisis is exacting a rising price from the worldwide insurance industry, a relief and development agency says.

LONDON, 11 January, 2021 – The economic cost of the climate crisis keeps on rising, as the world’s insurance industry is now acutely aware. As the world digests the news that 2020 was the joint hottest year on record, two reports attempt to assess how many billions of dollars are being lost as a result of an ever-warming planet.

Christian Aid, the UK and Ireland-based charity, lists what it considers to be the 15 most serious climate-related disasters in 2020, and seeks to quantify them in financial terms.

“Covid-19 may have dominated the news agenda in 2020, but for many people the ongoing climate crisis compounded that into an even bigger danger to their lives and livelihoods”, says Christian Aid.

Six of the ten most costly disasters happened in Asia, many of them associated with an unusually prolonged and wet monsoon season. The charity estimates that floods in China cost US$32 billion, while extended rains in India cost US$10bn. Cyclone Amphan, which in May hit the Bay of Bengal region – one of the world’s most densely populated areas – caused losses valued at US$13bn.

“Covid-19 has an expiry date, climate change does not, and failure to ‘green’ the global economic recovery now will increase costs for society in future”

In Africa, unusually heavy rains and changing wind patterns are considered to have been the main factors behind devastating infestations of locusts, which caused an estimated US$8.5bn of damage to crops in Kenya and other East African countries.

In its latest update on locust breeding and movement patterns, the UN’s Food and Agriculture Organisation warns that swarms are likely to continue devastating crops across the Arabian peninsula and in East Africa in the weeks ahead.

Christian Aid says its calculations of financial losses resulting from climate crisis-related events are likely to be an underestimate. “Most of these estimates are based only on insured losses, meaning the true financial costs are likely to be higher”, the report says.

Insurance is a very unequal business: much of the property and economic infrastructure of the developing world is not insured, with the bulk of cover being in the US, Europe and other leading economies.

Australian toll

Swiss Re is one of the world’s biggest insurance groups. Its preliminary estimate of global insurance losses as a result of both what it terms natural catastrophes and man-made disasters in 2020 amounts to US$83bn, up 40% on the previous year. A large chunk of those losses resulted from claims related to extreme weather events in the US.

“Losses were driven by a record number of severe convective storms (thunderstorms with tornadoes, floods and hail) and wildfires in the US”, says Swiss Re. Wildfires in Australia were another contributing factor.

The group says climate change is likely to exacerbate what it calls secondary peril events, as more humid air and rising temperatures create extreme weather conditions, which in turn will result in more frequent wildfires, storm surges and floods.

“While Covid-19 has an expiry date, climate change does not, and failure to ‘green’ the global economic recovery now will increase costs for society in future”, says Jerome Jean Haegeli, Swiss Re’s chief economist. – Climate News Network

The climate crisis is exacting a rising price from the worldwide insurance industry, a relief and development agency says.

LONDON, 11 January, 2021 – The economic cost of the climate crisis keeps on rising, as the world’s insurance industry is now acutely aware. As the world digests the news that 2020 was the joint hottest year on record, two reports attempt to assess how many billions of dollars are being lost as a result of an ever-warming planet.

Christian Aid, the UK and Ireland-based charity, lists what it considers to be the 15 most serious climate-related disasters in 2020, and seeks to quantify them in financial terms.

“Covid-19 may have dominated the news agenda in 2020, but for many people the ongoing climate crisis compounded that into an even bigger danger to their lives and livelihoods”, says Christian Aid.

Six of the ten most costly disasters happened in Asia, many of them associated with an unusually prolonged and wet monsoon season. The charity estimates that floods in China cost US$32 billion, while extended rains in India cost US$10bn. Cyclone Amphan, which in May hit the Bay of Bengal region – one of the world’s most densely populated areas – caused losses valued at US$13bn.

“Covid-19 has an expiry date, climate change does not, and failure to ‘green’ the global economic recovery now will increase costs for society in future”

In Africa, unusually heavy rains and changing wind patterns are considered to have been the main factors behind devastating infestations of locusts, which caused an estimated US$8.5bn of damage to crops in Kenya and other East African countries.

In its latest update on locust breeding and movement patterns, the UN’s Food and Agriculture Organisation warns that swarms are likely to continue devastating crops across the Arabian peninsula and in East Africa in the weeks ahead.

Christian Aid says its calculations of financial losses resulting from climate crisis-related events are likely to be an underestimate. “Most of these estimates are based only on insured losses, meaning the true financial costs are likely to be higher”, the report says.

Insurance is a very unequal business: much of the property and economic infrastructure of the developing world is not insured, with the bulk of cover being in the US, Europe and other leading economies.

Australian toll

Swiss Re is one of the world’s biggest insurance groups. Its preliminary estimate of global insurance losses as a result of both what it terms natural catastrophes and man-made disasters in 2020 amounts to US$83bn, up 40% on the previous year. A large chunk of those losses resulted from claims related to extreme weather events in the US.

“Losses were driven by a record number of severe convective storms (thunderstorms with tornadoes, floods and hail) and wildfires in the US”, says Swiss Re. Wildfires in Australia were another contributing factor.

The group says climate change is likely to exacerbate what it calls secondary peril events, as more humid air and rising temperatures create extreme weather conditions, which in turn will result in more frequent wildfires, storm surges and floods.

“While Covid-19 has an expiry date, climate change does not, and failure to ‘green’ the global economic recovery now will increase costs for society in future”, says Jerome Jean Haegeli, Swiss Re’s chief economist. – Climate News Network

World still warms in 2020 as greenhouse gases fall

Greenhouse gases have fallen during 2020. But that’s no reason for congratulations, in a year of climate drama.

LONDON, 11 December, 2020 − The year of the coronavirus − the year of global lockdown − meant a record fall in emissions of the greenhouse gases that drive global warming: by December there had been 34 billion tonnes of carbon dioxide from fossil fuel combustion worldwide, a fall of 7% compared with 2019, according to a new study.

If governments followed the economic shutdown with what the UN calls a “green pandemic recovery”, then by 2030 greenhouse gas emissions could fall by up to 25%. That remains a “big if.” Right now the planet is heading towards an end-of-century average temperature rise of a calamitous 3°C, according to a second report.

And a third summary of the last 12 months finds the pandemic changed almost nothing, says the World Meteorological Organisation (WMO). The year looks to be one of the three warmest on record, in the warmest decade on record. The warmest six years ever recorded have all happened since 2015.

The news in the journal Earth System Science Data, that humankind managed not to add 2.4 bn tonnes of CO2 to the atmosphere because car journeys fell by half and airline flights dwindled at the peak of the lockdowns from Covid-19, should be encouraging.

“There is at least a one in five chance of [the world] temporarily exceeding 1.5°C by 2024. 2020 has been yet another extraordinary year for our climate”

To be on track to meet the promises made under the Paris Agreement of 2015, humankind has to reduce emissions by around 1 to 2 billion tonnes a year for the next ten years. Nobody can yet say whether the decline will continue, or whether emissions will rebound.

“All the elements are not yet in place for sustained decreases in global emissions, and emissions are slowly edging back to 2019 levels”, warned Corinne Le Quéré, of the University of East Anglia, UK. “Government actions to stimulate the economy at the end of the Covid-19 pandemic can also help lower emissions and tackle climate change.”

Here is the message of the United Nations Environment Programme’s latest Emissions Gap Report. Examining the gap between what nations promised to do in Paris, and what is actually happening, it warns that a 7% drop in emissions during 2020 translates to a reduction in global warming by 2050 of no more than 0.01°C.

If nations stepped into economic recovery with plans to advance renewable energy and save fossil fuel use, a 25% emissions cut could indeed create a chance of meeting the 2°C limit promised in the Paris Agreement. But it wouldn’t get the world to the real goal of a rise of no more than 1.5°C by 2100.

Roasting Arctic

Greenhouse gases continue to inflict a relentless burden. Right now the world is already 1.2°C warmer than at any time for almost all of human history, thanks to profligate fossil fuel use over the last century. And, says the WMO’s secretary-general Petteri Taalas, “there is at least a one in five chance of it temporarily exceeding 1.5°C by 2024.”

Ocean heat has reached record levels and 80% of the blue planet experienced at least one marine heatwave in the last year, says a summary of the year based on evidence from January to October. In the Siberian Arctic, temperatures were 5°C above normal. The Arctic summer sea ice was the second-lowest since records began 42 years ago. In California’s Death Valley in August, the thermometer hit 54.4°C, the highest anywhere in the world for at least the last 80 years.

“2020 has, unfortunately, been yet another extraordinary year for our climate. We saw new extreme temperatures on land, sea and especially in the Arctic. Wildfires consumed vast areas in Australia, Siberia, the US West Coast and South America, sending plumes of smoke circumnavigating the globe,” Professor Taalas said.

“We saw a record number of hurricanes in the Atlantic, including unprecedented back-to-back category 4 hurricanes in Central America in November. Flooding in parts of Africa and South-east Asia led to massive population displacement and undermined food security for millions.” − Climate News Network

Greenhouse gases have fallen during 2020. But that’s no reason for congratulations, in a year of climate drama.

LONDON, 11 December, 2020 − The year of the coronavirus − the year of global lockdown − meant a record fall in emissions of the greenhouse gases that drive global warming: by December there had been 34 billion tonnes of carbon dioxide from fossil fuel combustion worldwide, a fall of 7% compared with 2019, according to a new study.

If governments followed the economic shutdown with what the UN calls a “green pandemic recovery”, then by 2030 greenhouse gas emissions could fall by up to 25%. That remains a “big if.” Right now the planet is heading towards an end-of-century average temperature rise of a calamitous 3°C, according to a second report.

And a third summary of the last 12 months finds the pandemic changed almost nothing, says the World Meteorological Organisation (WMO). The year looks to be one of the three warmest on record, in the warmest decade on record. The warmest six years ever recorded have all happened since 2015.

The news in the journal Earth System Science Data, that humankind managed not to add 2.4 bn tonnes of CO2 to the atmosphere because car journeys fell by half and airline flights dwindled at the peak of the lockdowns from Covid-19, should be encouraging.

“There is at least a one in five chance of [the world] temporarily exceeding 1.5°C by 2024. 2020 has been yet another extraordinary year for our climate”

To be on track to meet the promises made under the Paris Agreement of 2015, humankind has to reduce emissions by around 1 to 2 billion tonnes a year for the next ten years. Nobody can yet say whether the decline will continue, or whether emissions will rebound.

“All the elements are not yet in place for sustained decreases in global emissions, and emissions are slowly edging back to 2019 levels”, warned Corinne Le Quéré, of the University of East Anglia, UK. “Government actions to stimulate the economy at the end of the Covid-19 pandemic can also help lower emissions and tackle climate change.”

Here is the message of the United Nations Environment Programme’s latest Emissions Gap Report. Examining the gap between what nations promised to do in Paris, and what is actually happening, it warns that a 7% drop in emissions during 2020 translates to a reduction in global warming by 2050 of no more than 0.01°C.

If nations stepped into economic recovery with plans to advance renewable energy and save fossil fuel use, a 25% emissions cut could indeed create a chance of meeting the 2°C limit promised in the Paris Agreement. But it wouldn’t get the world to the real goal of a rise of no more than 1.5°C by 2100.

Roasting Arctic

Greenhouse gases continue to inflict a relentless burden. Right now the world is already 1.2°C warmer than at any time for almost all of human history, thanks to profligate fossil fuel use over the last century. And, says the WMO’s secretary-general Petteri Taalas, “there is at least a one in five chance of it temporarily exceeding 1.5°C by 2024.”

Ocean heat has reached record levels and 80% of the blue planet experienced at least one marine heatwave in the last year, says a summary of the year based on evidence from January to October. In the Siberian Arctic, temperatures were 5°C above normal. The Arctic summer sea ice was the second-lowest since records began 42 years ago. In California’s Death Valley in August, the thermometer hit 54.4°C, the highest anywhere in the world for at least the last 80 years.

“2020 has, unfortunately, been yet another extraordinary year for our climate. We saw new extreme temperatures on land, sea and especially in the Arctic. Wildfires consumed vast areas in Australia, Siberia, the US West Coast and South America, sending plumes of smoke circumnavigating the globe,” Professor Taalas said.

“We saw a record number of hurricanes in the Atlantic, including unprecedented back-to-back category 4 hurricanes in Central America in November. Flooding in parts of Africa and South-east Asia led to massive population displacement and undermined food security for millions.” − Climate News Network

China and Australia face a climate tipping point

Once again, scientists warn that at least part of the world could be facing a climate tipping point. Two parts, in fact.

LONDON, 8 December 2020 − The grasslands of northern China and Mongolia could be about to lurch into a climate tipping point, an irreversible sequence of heat and drought.

This is a landscape that helped shape world history. The Hun forces that humbled the western Roman Empire 16 centuries ago, and the conquering hordes led by Genghis Khan that commanded most of the Asian continent and threatened Europe eight centuries later, both emerged from tribes of nomad herdsmen from its grasslands. Now it could itself be about to be reconfigured by human-driven climate change.

And that same anthropogenic climate tipping point poses the same threat to great tracts of south-east Australia: water could become more scarce, bush fires could become more frequent, and winds could begin to blow away the parched soils in droughts that could last decades, or even centuries.

Both studies are based on evidence from the past, and both on the story told by preserved annual growth rings. The warning from inner East Asia is based on the testimony of tree stumps and timbers from the last 260 years, say researchers in the journal Science.

“They’re alarming findings, in a long list of alarming findings…if humans continue to warm the planet, this is the future we may all be looking at”

The patterns of tree growth suggest that the recent consecutive summers marked by both heat and drought are new events, and could increase in frequency.

The high plains of central Asia can be very cold in winter, very hot in summer. But soil moisture normally evaporates to cool the air at the surface. In a sustained drought, the air becomes hotter. In recent years, the region’s lakes have been shrinking in extent − and in number.

“The result is more heatwaves, which means more soil water losses, which means more heatwaves − and where this might end, we cannot say,” said Deliang Chen of the University of Gothenburg in Sweden, one of the research team.

He and his co-authors warn bluntly that the double impact of sustained heat and prolonged drought “is potentially irreversible beyond a tipping point in the East Asian climate system.”

Mega-drought link

The evidence from Australia is based on a much more distant past, and preserved in stalagmites deep in a cave in New South Wales. Researchers write in the journal Scientific Reports that during a warm interval in the last Ice Age, from 129,000 to 116,000 years ago, global temperatures rose to levels much as they are today, and perhaps slightly warmer.

And the record of lower falls of snow, higher temperatures and ever-scarcer water, preserved in the ancient annual growths of underground calcium carbonate, provided the scientists with a hint of what to expect in a world of global heating driven by ever-increasing use of fossil fuels, and ever-greater destruction of natural ecosystems.

“We found that, in the past, a similar amount of warming has been associated with mega-drought conditions all over south-eastern Australia. These drier conditions prevailed for centuries, sometimes for more than 1000 years,” said Hamish McGowan of the University of Queensland, who led the study.

“They’re alarming findings, in a long list of alarming findings that climate scientists have released over the last few decades. We hope that this new research allows for new insights to our future climate and the risks it may bring, such as drought and associated bushfires. But importantly, if humans continue to warm the planet, this is the future we may all be looking at.” − Climate News Network

Once again, scientists warn that at least part of the world could be facing a climate tipping point. Two parts, in fact.

LONDON, 8 December 2020 − The grasslands of northern China and Mongolia could be about to lurch into a climate tipping point, an irreversible sequence of heat and drought.

This is a landscape that helped shape world history. The Hun forces that humbled the western Roman Empire 16 centuries ago, and the conquering hordes led by Genghis Khan that commanded most of the Asian continent and threatened Europe eight centuries later, both emerged from tribes of nomad herdsmen from its grasslands. Now it could itself be about to be reconfigured by human-driven climate change.

And that same anthropogenic climate tipping point poses the same threat to great tracts of south-east Australia: water could become more scarce, bush fires could become more frequent, and winds could begin to blow away the parched soils in droughts that could last decades, or even centuries.

Both studies are based on evidence from the past, and both on the story told by preserved annual growth rings. The warning from inner East Asia is based on the testimony of tree stumps and timbers from the last 260 years, say researchers in the journal Science.

“They’re alarming findings, in a long list of alarming findings…if humans continue to warm the planet, this is the future we may all be looking at”

The patterns of tree growth suggest that the recent consecutive summers marked by both heat and drought are new events, and could increase in frequency.

The high plains of central Asia can be very cold in winter, very hot in summer. But soil moisture normally evaporates to cool the air at the surface. In a sustained drought, the air becomes hotter. In recent years, the region’s lakes have been shrinking in extent − and in number.

“The result is more heatwaves, which means more soil water losses, which means more heatwaves − and where this might end, we cannot say,” said Deliang Chen of the University of Gothenburg in Sweden, one of the research team.

He and his co-authors warn bluntly that the double impact of sustained heat and prolonged drought “is potentially irreversible beyond a tipping point in the East Asian climate system.”

Mega-drought link

The evidence from Australia is based on a much more distant past, and preserved in stalagmites deep in a cave in New South Wales. Researchers write in the journal Scientific Reports that during a warm interval in the last Ice Age, from 129,000 to 116,000 years ago, global temperatures rose to levels much as they are today, and perhaps slightly warmer.

And the record of lower falls of snow, higher temperatures and ever-scarcer water, preserved in the ancient annual growths of underground calcium carbonate, provided the scientists with a hint of what to expect in a world of global heating driven by ever-increasing use of fossil fuels, and ever-greater destruction of natural ecosystems.

“We found that, in the past, a similar amount of warming has been associated with mega-drought conditions all over south-eastern Australia. These drier conditions prevailed for centuries, sometimes for more than 1000 years,” said Hamish McGowan of the University of Queensland, who led the study.

“They’re alarming findings, in a long list of alarming findings that climate scientists have released over the last few decades. We hope that this new research allows for new insights to our future climate and the risks it may bring, such as drought and associated bushfires. But importantly, if humans continue to warm the planet, this is the future we may all be looking at.” − Climate News Network

Drylands hit harder by poverty than richer regions

The arrival of the rains leaves the drylands hit harder than richer areas. Once again, climate change sows injustice.

LONDON, 7 December, 2020 − Not even the climate can be even-handed. When the rains come they leave the world’s drylands hit harder: the wealthier fare better and the poorest get relatively a little poorer. And the evidence is visible literally at the grassroots.

European scientists have been measuring vegetation growth as recorded in fine detail by satellite observation over the last 20 years. And they report that in the developing world, the vegetation that sprouts after rainfall on arid lands is more meagre, while in the better-off nations the same rainfall on the same kind of dryland terrain produces more healthy growth.

The consequence, researchers warn in the journal Nature Sustainability, could result in more food shortages, more disruption, and growing numbers of climate refugees.

“We observe a clear trend of arid areas developing in a negative direction in the most economically challenged countries,” said Rasmus Fensholt, of the University of Copenhagen, one of the authors.

“Here it is apparent that the growth of vegetation has become increasingly decoupled from the water resources available, and that there is simply less vegetation in relation to the amount of rainfall. The opposite is the case in the wealthiest countries.”

“One consequence of declining vegetation in the world’s poorer arid regions may be an increase in climate refugees from various African countries. There is no indication that the problem will diminish”

Roughly 40% of the Earth’s habitable land is arid or semi-arid, and the global drylands are home to almost a third of all humanity, around half of all the planet’s birds and mammals, as well as providing range for livestock and land for crops. Most of the world’s drylands are also home to many of the world’s least developed countries, and many of the poorest citizenry.

And, in a world of climate change driven by ever-rising global temperatures, fuelled in turn by greenhouse gas emissions from increasing fossil fuel use, things don’t look promising.

Research from the last four decades has repeatedly predicted that although global rainfall may be higher in total, those regions already well-watered will tend to become wetter, while those that have adapted to arid climate regimes will get drier. By the end of this century the proportion defined as dryland may have expanded by 23%.

And although higher temperatures, higher levels of atmospheric carbon and changes in rainfall regimes have had the overall effect of “greening” many of the drylands, those already struggling to survive are getting less benefit from any rain that falls.

The scientists, from Denmark, Norway, Sweden and the Netherlands, made a close analysis of satellite imagery from 2000 to 2015 to identify not rainfall changes, but vegetation productivity in relation to rainfall: they found pronounced differences across regions and continents. Drylands in Africa and Asia fared proportionately less well compared to South America and Australia.

Upward trend reversed

What made the difference, they think, is the number and the plight of the people on whom the rain fell. Rapid population growth in Africa meant greater pressure on land less suitable for agriculture, and more intense grazing on already fragile grassland cover.

In the richer nations, conversely, farms had expanded and intensified with help from fertiliser and irrigation.

This is not the first study to find that in a world of climate change, the poorest − among them those who have contributed least to global heating − will be hit hardest. The match of more people with less productive land can only mean more competition for less food at higher prices.

“One consequence of declining vegetation in the world’s poorer arid regions may be an increase in climate refugees from various African countries. According to what we have seen in this study, there is no indication that the problem will diminish in future,” Professor Fensholt said.

“We have been pleased to see that, for a number of years, vegetation has been on an upwards trend in arid regions. But if we dig only a tiny bit deeper and look at how successfully precipitation has translated into vegetation, then climate change seems to be hitting unevenly, which is troubling.” − Climate News Network

The arrival of the rains leaves the drylands hit harder than richer areas. Once again, climate change sows injustice.

LONDON, 7 December, 2020 − Not even the climate can be even-handed. When the rains come they leave the world’s drylands hit harder: the wealthier fare better and the poorest get relatively a little poorer. And the evidence is visible literally at the grassroots.

European scientists have been measuring vegetation growth as recorded in fine detail by satellite observation over the last 20 years. And they report that in the developing world, the vegetation that sprouts after rainfall on arid lands is more meagre, while in the better-off nations the same rainfall on the same kind of dryland terrain produces more healthy growth.

The consequence, researchers warn in the journal Nature Sustainability, could result in more food shortages, more disruption, and growing numbers of climate refugees.

“We observe a clear trend of arid areas developing in a negative direction in the most economically challenged countries,” said Rasmus Fensholt, of the University of Copenhagen, one of the authors.

“Here it is apparent that the growth of vegetation has become increasingly decoupled from the water resources available, and that there is simply less vegetation in relation to the amount of rainfall. The opposite is the case in the wealthiest countries.”

“One consequence of declining vegetation in the world’s poorer arid regions may be an increase in climate refugees from various African countries. There is no indication that the problem will diminish”

Roughly 40% of the Earth’s habitable land is arid or semi-arid, and the global drylands are home to almost a third of all humanity, around half of all the planet’s birds and mammals, as well as providing range for livestock and land for crops. Most of the world’s drylands are also home to many of the world’s least developed countries, and many of the poorest citizenry.

And, in a world of climate change driven by ever-rising global temperatures, fuelled in turn by greenhouse gas emissions from increasing fossil fuel use, things don’t look promising.

Research from the last four decades has repeatedly predicted that although global rainfall may be higher in total, those regions already well-watered will tend to become wetter, while those that have adapted to arid climate regimes will get drier. By the end of this century the proportion defined as dryland may have expanded by 23%.

And although higher temperatures, higher levels of atmospheric carbon and changes in rainfall regimes have had the overall effect of “greening” many of the drylands, those already struggling to survive are getting less benefit from any rain that falls.

The scientists, from Denmark, Norway, Sweden and the Netherlands, made a close analysis of satellite imagery from 2000 to 2015 to identify not rainfall changes, but vegetation productivity in relation to rainfall: they found pronounced differences across regions and continents. Drylands in Africa and Asia fared proportionately less well compared to South America and Australia.

Upward trend reversed

What made the difference, they think, is the number and the plight of the people on whom the rain fell. Rapid population growth in Africa meant greater pressure on land less suitable for agriculture, and more intense grazing on already fragile grassland cover.

In the richer nations, conversely, farms had expanded and intensified with help from fertiliser and irrigation.

This is not the first study to find that in a world of climate change, the poorest − among them those who have contributed least to global heating − will be hit hardest. The match of more people with less productive land can only mean more competition for less food at higher prices.

“One consequence of declining vegetation in the world’s poorer arid regions may be an increase in climate refugees from various African countries. According to what we have seen in this study, there is no indication that the problem will diminish in future,” Professor Fensholt said.

“We have been pleased to see that, for a number of years, vegetation has been on an upwards trend in arid regions. But if we dig only a tiny bit deeper and look at how successfully precipitation has translated into vegetation, then climate change seems to be hitting unevenly, which is troubling.” − Climate News Network

Australian forests’ smoke climbed 20 miles in 2019

Blazing Australian forests made their mark high in the stratosphere and cast a cloud that lingered for months.

LONDON, 4 November, 2020 − Australian forests, devoured by devastating wildfires in the last southern hemisphere summer, set a new high − a huge smoke cloud that soared more than 20 miles into the upper atmosphere and stayed there for months.

An international team of scientists reports in the Nature journal Communications Earth and Environment that they tracked the cloud to an altitude of 35 kilometres (21 miles).

They measured it as 1,000 kms (625 miles) across. They followed it around the planet for 66,000 kms (41,010 miles). And they confirm that it remained intact for three months.

This high-flying pollution wasn’t the first such instance: just three times the size of any observed predecessor. Until now the record was held by plumes soaring from forest fires in western Canada in 2017.

Growing intensity

“When I saw the satellite measurement of the smoke plume at 35 kms, it was jaw-dropping. I never would have expected that”, said Adam Bourassa of the University of Saskatchewan in Canada, one of the researchers.

“We’re seeing records broken in terms of the impact on the atmosphere from these fires. Knowing that they’re likely to strike more frequently and with more intensity due to climate change, we could end up with a pretty dramatically changed atmosphere.”

A blaze that can make a new cloud 35 kms above its surface is an indicator both of the potential devastation of climate change driven by profligate human use of fossil fuels and of the intricate workings of the biosphere and atmosphere.

After months of desperate drought in 2019, eastern Australia effectively caught fire. Around 110,000 sq kms of bush, forest and grassland went up in smoke: with them went thousands of homes and millions of wild and domestic animals. Altogether 33 people died.

“We’re seeing records broken in terms of the impact on the atmosphere from these fires … we could end up with a pretty dramatically changed atmosphere”

So huge and sustained were the fires, and so dense the smoke, that the fires began to generate their own thunderstorms, known as pyrocumulonimbus, to create powerful updrafts to carry the aerosols and soot far above the flight paths of the highest jet airliners.

Researchers from France, the UK and Canada used sensitive satellite readings to track the sustained smoke signal from a part-incinerated island: at altitude, it was still dense enough to absorb, scatter and weaken the sunlight falling on the Earth below.

“What was also really amazing was that as the smoke sits in the atmosphere, it starts to absorb sunlight and so it starts to heat up,” Professor Bourassa said.

“And then, because it’s getting hotter, it starts to rise in a swirling vortex bubble, and it just rose higher and higher through the atmosphere.” − Climate News Network

Blazing Australian forests made their mark high in the stratosphere and cast a cloud that lingered for months.

LONDON, 4 November, 2020 − Australian forests, devoured by devastating wildfires in the last southern hemisphere summer, set a new high − a huge smoke cloud that soared more than 20 miles into the upper atmosphere and stayed there for months.

An international team of scientists reports in the Nature journal Communications Earth and Environment that they tracked the cloud to an altitude of 35 kilometres (21 miles).

They measured it as 1,000 kms (625 miles) across. They followed it around the planet for 66,000 kms (41,010 miles). And they confirm that it remained intact for three months.

This high-flying pollution wasn’t the first such instance: just three times the size of any observed predecessor. Until now the record was held by plumes soaring from forest fires in western Canada in 2017.

Growing intensity

“When I saw the satellite measurement of the smoke plume at 35 kms, it was jaw-dropping. I never would have expected that”, said Adam Bourassa of the University of Saskatchewan in Canada, one of the researchers.

“We’re seeing records broken in terms of the impact on the atmosphere from these fires. Knowing that they’re likely to strike more frequently and with more intensity due to climate change, we could end up with a pretty dramatically changed atmosphere.”

A blaze that can make a new cloud 35 kms above its surface is an indicator both of the potential devastation of climate change driven by profligate human use of fossil fuels and of the intricate workings of the biosphere and atmosphere.

After months of desperate drought in 2019, eastern Australia effectively caught fire. Around 110,000 sq kms of bush, forest and grassland went up in smoke: with them went thousands of homes and millions of wild and domestic animals. Altogether 33 people died.

“We’re seeing records broken in terms of the impact on the atmosphere from these fires … we could end up with a pretty dramatically changed atmosphere”

So huge and sustained were the fires, and so dense the smoke, that the fires began to generate their own thunderstorms, known as pyrocumulonimbus, to create powerful updrafts to carry the aerosols and soot far above the flight paths of the highest jet airliners.

Researchers from France, the UK and Canada used sensitive satellite readings to track the sustained smoke signal from a part-incinerated island: at altitude, it was still dense enough to absorb, scatter and weaken the sunlight falling on the Earth below.

“What was also really amazing was that as the smoke sits in the atmosphere, it starts to absorb sunlight and so it starts to heat up,” Professor Bourassa said.

“And then, because it’s getting hotter, it starts to rise in a swirling vortex bubble, and it just rose higher and higher through the atmosphere.” − Climate News Network

Hotter oceans make the tropics expand polewards

The tropical climate zones are not just warmer, they now cover more of the planet. Blame it on steadily hotter oceans.

LONDON, 27 August, 2020 – The tropics are on the march and US and German scientists think they know why: hotter oceans have taken control.

The parched, arid fringes of the hot, moist conditions that nourish the equatorial forest band around the middle of the globe are moving, unevenly, further north and south in response to climate change.

And the role of the ocean is made even more dramatic in the southern hemisphere: because the ocean south of the equator is so much bigger than in the north, the southward shift of the parched zone is even more pronounced.

Across the globe, things don’t look good for places like California, which has already suffered some of its worst droughts and fires on record, and  Australia, where drought and fire if possible have been even worse.

In the past century or so, carbon dioxide levels in the atmosphere have risen from what was once a stable average of 285 parts per million to more than 400 ppm, and global average temperatures are now at least 1°C higher than they have been for most of human history.

“We demonstrate that the enhanced subtropical ocean warming is independent from the natural climate oscillations. This is a result of global warming”

And although the fastest and most dramatic changes in the world have been in the coldest zones – and particularly the Arctic – the tropics, too, have begun to feel the heat.

Researchers have observed tropical fish moving into cooler waters; they have warned that some tropical plant species may soon find temperatures too high for germination; they have mapped tropical cyclones hitting further north and south with time, and doing more damage; and they have seen evidence that tropical diseases could soon advance even into temperate Europe.

But although satellite observations have revealed that the tropical climate zone has expanded beyond the formal limits known as the Tropics of Capricorn and Cancer, and is doing so at somewhere between a quarter and half a degree of latitude each decade, no one has been able to work out why the shift is more pronounced in the southern half of the globe.

Now a new study in the Journal of Geophysical Research: Atmospheres offers an answer. The expansion of the tropics has been driven by ocean warming.

And if that expansion is more obvious in the southern hemisphere, it is because there is more sea to have more impact.

Clear link

Researchers analysed water temperature patterns in the great ocean gyres, those giant circular currents that take warm waters to the poles and return cold water to the equatorial regions.

They matched satellite readings from 1982 – the first year in the series of measurements – with data from 2018, and compared these to measurements of tropical zone expansion.

The connection was clear: excess heat that had been building up in the subtropical oceans ever since global warming began had driven both tropical edges and ocean gyres towards the poles.

That is, the shift in the tropics wasn’t just one of those slow pulses of expansion and retraction, of cyclic change, that happen in a complex world. And more precisely, the tropics were expanding more clearly in those places where the gyres moved poleward.

“We demonstrate that the enhanced subtropical ocean warming is independent from the natural climate oscillations,” said Hu Yang of the Alfred Wegener Institute in Bremerhaven, Germany, who led the research. “This is a result of global warming.” – Climate News Network

The tropical climate zones are not just warmer, they now cover more of the planet. Blame it on steadily hotter oceans.

LONDON, 27 August, 2020 – The tropics are on the march and US and German scientists think they know why: hotter oceans have taken control.

The parched, arid fringes of the hot, moist conditions that nourish the equatorial forest band around the middle of the globe are moving, unevenly, further north and south in response to climate change.

And the role of the ocean is made even more dramatic in the southern hemisphere: because the ocean south of the equator is so much bigger than in the north, the southward shift of the parched zone is even more pronounced.

Across the globe, things don’t look good for places like California, which has already suffered some of its worst droughts and fires on record, and  Australia, where drought and fire if possible have been even worse.

In the past century or so, carbon dioxide levels in the atmosphere have risen from what was once a stable average of 285 parts per million to more than 400 ppm, and global average temperatures are now at least 1°C higher than they have been for most of human history.

“We demonstrate that the enhanced subtropical ocean warming is independent from the natural climate oscillations. This is a result of global warming”

And although the fastest and most dramatic changes in the world have been in the coldest zones – and particularly the Arctic – the tropics, too, have begun to feel the heat.

Researchers have observed tropical fish moving into cooler waters; they have warned that some tropical plant species may soon find temperatures too high for germination; they have mapped tropical cyclones hitting further north and south with time, and doing more damage; and they have seen evidence that tropical diseases could soon advance even into temperate Europe.

But although satellite observations have revealed that the tropical climate zone has expanded beyond the formal limits known as the Tropics of Capricorn and Cancer, and is doing so at somewhere between a quarter and half a degree of latitude each decade, no one has been able to work out why the shift is more pronounced in the southern half of the globe.

Now a new study in the Journal of Geophysical Research: Atmospheres offers an answer. The expansion of the tropics has been driven by ocean warming.

And if that expansion is more obvious in the southern hemisphere, it is because there is more sea to have more impact.

Clear link

Researchers analysed water temperature patterns in the great ocean gyres, those giant circular currents that take warm waters to the poles and return cold water to the equatorial regions.

They matched satellite readings from 1982 – the first year in the series of measurements – with data from 2018, and compared these to measurements of tropical zone expansion.

The connection was clear: excess heat that had been building up in the subtropical oceans ever since global warming began had driven both tropical edges and ocean gyres towards the poles.

That is, the shift in the tropics wasn’t just one of those slow pulses of expansion and retraction, of cyclic change, that happen in a complex world. And more precisely, the tropics were expanding more clearly in those places where the gyres moved poleward.

“We demonstrate that the enhanced subtropical ocean warming is independent from the natural climate oscillations,” said Hu Yang of the Alfred Wegener Institute in Bremerhaven, Germany, who led the research. “This is a result of global warming.” – Climate News Network

Heat may leave tropical trees unable to germinate

If a plant can’t germinate, it’s heading for extinction. For many tropical trees, conditions could soon become too hot to procreate.

LONDON, 14 July, 2020 – There could soon be real trouble for tropical trees and other plants. As global average temperatures rise, in response to ever more profligate use of fossil fuels, it may for some species become too hot to successfully germinate.

The foliage most at risk from this thermal barrier to reproduction is certain to be in the tropics, where tens of thousands of plant species have already adapted to very nearly the limits of their tolerance.

Australian researchers report in the journal Global Ecology and Biogeography that they looked at 9,737 records for 1,312 species worldwide from the Kew Gardens’ global germination database, to work out the temperature ranges that suit germination.

They report that the closer to the equator, the more the risk that by 2070 temperatures could rise high enough to exceed the ceiling below which germination is possible.

More than half of all the tropical seedlings tested – 79 out of 142 – would experience temperatures higher than the optimum for breeding. And 41 out of 190 would meet temperatures that would be higher than the maximum at which seeds would germinate.

Survival impossible

“These plants are more at risk because they are near their upper limits. So even a small increase in temperature from climate change could push them over the edge,” said Alexander Sentinella, of the University of New South Wales, who led the study.

“The figures are quite shocking because by 2070 more than 20% of tropical plant species, we predict, will face temperatures above their upper limit, which means they won’t germinate, and so can’t survive.”

The world’s tropical forests are already in trouble. Altogether there could be three trillion trees on the planet, and humans are already removing 15 billion a year. The richest habitats are in the tropics.

There could be 40,000 species of tree that flourish in the equatorial forests, and half of these have already been pronounced threatened. The hot moist forests provide cover for myriad smaller shrubs and plants under the canopy, and they flourish alongside a mosaic of wetland and grassland habitats to support some of the richest biodiversity on the planet.

The forests and the plants in them absorb a high proportion of the extra carbon dioxide emitted from power station and vehicle exhausts, they serve as a sponge to store rainy season water, and they recycle the planet’s oxygen. They are under increasing stress from human exploitation and climate change.

“These plants are more at risk because they are near their upper limits. So even a small increase in temperature from climate change could push them over the edge”

Higher temperatures mean greater extremes of windstorm that can severely damage whole forests; higher temperatures mean more intense droughts and greater fire hazard; climate change has begun to alter the mix, variety and abundance of tree species both in the tropics and worldwide; and where they can, tropical species have already begun to colonise higher ground to stay within suitable temperature boundaries.

So the realisation that plant species – like animals on land and fish in the oceans – may be most vulnerable at a key moment of the life cycle is even more bad news. Many species will still be able to reproduce, but if they have already gone beyond the optimum for germination, then the success rate will be smaller.

The news on a global scale is more encouraging: the researchers found that 95% of species at latitudes higher than 45° could actually benefit from global warming, because temperatures could shift more closely to the optimum for many temperate and cool zone plants. And some plant species may evolve as temperatures rise. But many will not adapt in time to rapidly-rising global temperatures.

“There are almost 400,000 plant species worldwide – so we would expect a number of them to fail to germinate between now and 2070,” Sentinella said.

“Humans have known about the dangers of climate change for decades, and we already have the answers to tackle it. Hopefully, our study will encourage people and policymakers to take action now.” – Climate News Network

If a plant can’t germinate, it’s heading for extinction. For many tropical trees, conditions could soon become too hot to procreate.

LONDON, 14 July, 2020 – There could soon be real trouble for tropical trees and other plants. As global average temperatures rise, in response to ever more profligate use of fossil fuels, it may for some species become too hot to successfully germinate.

The foliage most at risk from this thermal barrier to reproduction is certain to be in the tropics, where tens of thousands of plant species have already adapted to very nearly the limits of their tolerance.

Australian researchers report in the journal Global Ecology and Biogeography that they looked at 9,737 records for 1,312 species worldwide from the Kew Gardens’ global germination database, to work out the temperature ranges that suit germination.

They report that the closer to the equator, the more the risk that by 2070 temperatures could rise high enough to exceed the ceiling below which germination is possible.

More than half of all the tropical seedlings tested – 79 out of 142 – would experience temperatures higher than the optimum for breeding. And 41 out of 190 would meet temperatures that would be higher than the maximum at which seeds would germinate.

Survival impossible

“These plants are more at risk because they are near their upper limits. So even a small increase in temperature from climate change could push them over the edge,” said Alexander Sentinella, of the University of New South Wales, who led the study.

“The figures are quite shocking because by 2070 more than 20% of tropical plant species, we predict, will face temperatures above their upper limit, which means they won’t germinate, and so can’t survive.”

The world’s tropical forests are already in trouble. Altogether there could be three trillion trees on the planet, and humans are already removing 15 billion a year. The richest habitats are in the tropics.

There could be 40,000 species of tree that flourish in the equatorial forests, and half of these have already been pronounced threatened. The hot moist forests provide cover for myriad smaller shrubs and plants under the canopy, and they flourish alongside a mosaic of wetland and grassland habitats to support some of the richest biodiversity on the planet.

The forests and the plants in them absorb a high proportion of the extra carbon dioxide emitted from power station and vehicle exhausts, they serve as a sponge to store rainy season water, and they recycle the planet’s oxygen. They are under increasing stress from human exploitation and climate change.

“These plants are more at risk because they are near their upper limits. So even a small increase in temperature from climate change could push them over the edge”

Higher temperatures mean greater extremes of windstorm that can severely damage whole forests; higher temperatures mean more intense droughts and greater fire hazard; climate change has begun to alter the mix, variety and abundance of tree species both in the tropics and worldwide; and where they can, tropical species have already begun to colonise higher ground to stay within suitable temperature boundaries.

So the realisation that plant species – like animals on land and fish in the oceans – may be most vulnerable at a key moment of the life cycle is even more bad news. Many species will still be able to reproduce, but if they have already gone beyond the optimum for germination, then the success rate will be smaller.

The news on a global scale is more encouraging: the researchers found that 95% of species at latitudes higher than 45° could actually benefit from global warming, because temperatures could shift more closely to the optimum for many temperate and cool zone plants. And some plant species may evolve as temperatures rise. But many will not adapt in time to rapidly-rising global temperatures.

“There are almost 400,000 plant species worldwide – so we would expect a number of them to fail to germinate between now and 2070,” Sentinella said.

“Humans have known about the dangers of climate change for decades, and we already have the answers to tackle it. Hopefully, our study will encourage people and policymakers to take action now.” – Climate News Network

The wetter world ahead will suffer worse droughts

Things are bad now, but worse droughts are coming. More rain will fall in a warmer world, but not where and when we need it.

LONDON, 26 June, 2020 – Australian scientists have bad news for drought-stricken and fire-ravaged fellow-citizens: still worse droughts are in store.

Even though the world will grow wetter as greenhouse gas emissions rise and planetary average temperatures soar, the droughts will endure for longer and become more intense.

And this will be true not just for a country with a government that seems anxious not to acknowledge the role of climate change in a procession of disasters. It will be true for California and much of the US West. It will be true for the Mediterranean and parts of Africa, and for any areas that lie within the drylands zone.

It could be true even for the tropical rainforests. Wherever average rainfall seems to be in decline, droughts will become more devastating. And that includes Central America and the Amazon.

“The earlier we act on reducing our emissions, the less economic and social pain we will feel in the future”

And even in the rainy zones where precipitation seems to be on the rise, and floods more frequent, when droughts happen they will be more intense, according to new research in the journal Geophysical Research Letters.

The conclusion, although alarming, is not new. It reinforces decades of earlier research predicting that as the world warms floods, superstorms and megadroughts could all increase.

Every rise of 1°C in planetary average temperatures means that the atmosphere’s capacity to absorb water vapour also increases: for every 1°C rise, rainfall will increase by 2%, and with every average increase the extremes will become ever more extreme.

The latest finding is a test of new climate models to be used by the Intergovernmental Panel on Climate Change (IPCC). Between 1998 and 2017, according to UN data, droughts have afflicted 1.5bn people and accounted for a third of all natural disaster impacts.

Search for precision

What will happen as humans go on burning ever more fossil fuels to raise planetary average temperatures ever higher will mean ever more severe tests for farmers, pastoralists, industry, natural ecosystems and national economies.

The latest study is an attempt to be a little more precise about the shape of the future in a warming world.

“We found the new models produced the most robust results for future droughts to date and that the degree of increase in drought duration and intensity was directly linked to the amounts of greenhouse gases emitted into the atmosphere,” said Anna Ukkola of the Australian National University in Canberra, who led the study.

“However, while these insights grow clearer with each advance, the message they deliver remains the same – the earlier we act on reducing our emissions, the less economic and social pain we will feel in the future.” – Climate News Network

Things are bad now, but worse droughts are coming. More rain will fall in a warmer world, but not where and when we need it.

LONDON, 26 June, 2020 – Australian scientists have bad news for drought-stricken and fire-ravaged fellow-citizens: still worse droughts are in store.

Even though the world will grow wetter as greenhouse gas emissions rise and planetary average temperatures soar, the droughts will endure for longer and become more intense.

And this will be true not just for a country with a government that seems anxious not to acknowledge the role of climate change in a procession of disasters. It will be true for California and much of the US West. It will be true for the Mediterranean and parts of Africa, and for any areas that lie within the drylands zone.

It could be true even for the tropical rainforests. Wherever average rainfall seems to be in decline, droughts will become more devastating. And that includes Central America and the Amazon.

“The earlier we act on reducing our emissions, the less economic and social pain we will feel in the future”

And even in the rainy zones where precipitation seems to be on the rise, and floods more frequent, when droughts happen they will be more intense, according to new research in the journal Geophysical Research Letters.

The conclusion, although alarming, is not new. It reinforces decades of earlier research predicting that as the world warms floods, superstorms and megadroughts could all increase.

Every rise of 1°C in planetary average temperatures means that the atmosphere’s capacity to absorb water vapour also increases: for every 1°C rise, rainfall will increase by 2%, and with every average increase the extremes will become ever more extreme.

The latest finding is a test of new climate models to be used by the Intergovernmental Panel on Climate Change (IPCC). Between 1998 and 2017, according to UN data, droughts have afflicted 1.5bn people and accounted for a third of all natural disaster impacts.

Search for precision

What will happen as humans go on burning ever more fossil fuels to raise planetary average temperatures ever higher will mean ever more severe tests for farmers, pastoralists, industry, natural ecosystems and national economies.

The latest study is an attempt to be a little more precise about the shape of the future in a warming world.

“We found the new models produced the most robust results for future droughts to date and that the degree of increase in drought duration and intensity was directly linked to the amounts of greenhouse gases emitted into the atmosphere,” said Anna Ukkola of the Australian National University in Canberra, who led the study.

“However, while these insights grow clearer with each advance, the message they deliver remains the same – the earlier we act on reducing our emissions, the less economic and social pain we will feel in the future.” – Climate News Network

Rare trees saved from Australia’s wildfires

This story originally appeared in the Bulletin of the Atomic Scientists and is republished here as part of Covering Climate Now, a global journalism collaboration to strengthen coverage of the climate story.

Buried amid the horrific news from Australia about climate change and out-of-control wildfire was a positive story: the saving of rare trees.

CHICAGO, 5 February, 2020 − An Associated Press story  titled Firefighters in Australia save unique prehistoric trees brought a scarce gleam of hope: “Firefighters winched from helicopters to reach the cluster of fewer than 200 Wollemi Pines in a remote gorge in the Blue Mountains a week before a massive wildfire bore down… the firefighters set up an irrigation system to keep the so-called dinosaur trees moist, and pumped water daily from the gorge as the blaze that had burned out of control for two months edged closer.”

This news had particular significance to me for a number of reasons. For one thing, the successful protection of this endangered species could hint at things to come − if we play our cards right.

For another, I know the Blue Mountains of New South Wales (though I have not been to that grove of trees − whose exact location has been kept a secret by botanists ever since it was first discovered in 1994.)

I spent four years down-under, first as an American researcher on a Fulbright grant to see what we in the States could learn from looking at the Australian experience, and then as a roving foreign correspondent for science-related US magazines such as International Wildlife, Scientific American, and the journal Science, among others.

My job was to travel over the land down-under, reporting on natural history, the environment, and science in the Great South Land for publications back home in the States − as well as magazines like Australian Geographic.

Easy to miss

Which was how I became acquainted with the Blue Mountains, a lesser-known area about 120 miles west of Sydney. They’re a surprisingly steep, thickly wooded, and easily overlooked mountain chain, much like an Aussie version of our Appalachians. And much like the Appalachians, their deep ravines held up westward exploration and expansion for a long time. But there the parallels end.

Walking in Australia’s Blue Mountains is an unworldly experience. There are no squirrels or chipmunks; instead, parrots occupy that ecological niche. My edition of the Field Guide to the Birds of Australia lists 23 different species of parrots alone.

Just a short list of the formal names of some of the individual species gives an idea of the colorful diversity you can see: Blue-winged, Orange-bellied, Golden-shouldered, Scarlet-chested, Red-rumped, and Turquoise parrots. Not to mention Elegant, Paradise, Superb, and King parrots.

And instead of smelling pine trees, your nose registers the scent of eucalypts. Look up at the stars at night, and there’s not a single familiar constellation; instead you see celestial objects like the Jewel Box Cluster − while hearing the mocking laugh of kookaburras.

Even the food tastes different − in place of pepperoni or sausage, toppings at the Australian Pizza Kitchen in Canberra include emu and kangaroo (I prefer the kangaroo).

“These trees are descendants of individuals that had survived since the era of the dinosaurs”

And some of the trees in parts of the Blueys − as they’re called − resemble nothing so much as short stumps with ferns popping out of their sides willy-nilly; everything looks so primeval you half-expect to see escapees from Jurassic Park poking their snouts out.

Indeed, in far-north Queensland I and my parents were to be stalked by a full-grown, adult male cassowary, defending his mate. We took shelter behind a large tropical tree, trying to keep the trunk between us and the approximately 200-pound, 6-foot-tall creature as it circled around.

This pervasive feeling of encounters with the primeval is appropriate. Australia is a very ancient land, which used to be part of what geologists call Gondwana − when most of the world’s landmasses were linked together in the distant past.

But while the other landforms went on to become continents such as South America and Africa, Australia remained a giant island continent, cut off from the rest of the planet. And species that died out elsewhere continued to thrive, and evolve, here.

(Just why species do so well on islands, and why evolution seems to speed up on them, is something that kept Charles Darwin busy. An entire field of island biogeography has sprung up to delve into its mysteries.)

Human rarities

Even now, some parts of Australia are so isolated that the wildlife has seldom seen humans. So far as researchers can tell, no Aborigines, Melanesians, Micronesians, Polynesians, or Caucasians ever settled on Australia’s Lord Howe Island until 1834; consequently, the wildlife never learned to be afraid of humans.

When I went there, you could stand at the foot of Lord Howe’s tallest mountain, call up to the providence petrels nesting as much as a hundred feet above, and watch the birds glide down to land at your feet. If you’re really good, you may be able to touch them, or at least have one land on your outstretched arm.

Due to these vagaries of isolation, ancient and unique species seem to abound in Australia − though they can be easily overlooked. Drive along the highway outside Shark Bay in the state of Western Australia, and you’ll spot weird dark, mushroom-shaped, rock-like structures in the shallows of the hyper-salty water; they’re actually living mats of blue-green algae known as stromatolites − Greek for “layered rock.”

Stromatolites are one of the oldest forms of life that we know of, essentially unchanged since their ancestors flourished 3.5 billion years ago. They were previously known to us only from fossils, until first discovered in this region in the 1980s.

So it’s not entirely surprising that Wollemi Pines should survive in the wild, undetected, a relatively short drive from Sydney for so many years; after all, these trees are descendants of individuals that had survived since the era of the dinosaurs − though they now exist in the wild in only one place in the world, with fewer than 100 adult specimens known.

Survivors for sale

What was surprising was that these wild specimens were saved from the wildfires, in a complex operation that involved firefighters being lowered from helicopters into the narrow steep-sided ridges where the trees dwell, along with planes strategically bombing the advancing firefront with fire retardant.

And well in advance of events these past months, authorities had covered their bets by doing all they could to increase the species’ chance of survival. Since 2006, a propagation program has made these trees available to botanical gardens so their numbers could be increased; I’ve subsequently run across Aussies who have grown the plants from seeds in their living rooms. (In Australia, seedlings can even be ordered online,  and the Royal Botanic Gardens Sydney offer information on Wollemi care, conservation, and research.)

More than that, when it looked like the wildfires were in imminent danger of destroying the only existing stand of these trees in the wild, leaders had the foresight to rely on the recommendations of scientists, firefighters, and other experts as to how to proceed. They then worked out a plan and put it into action − actively dealing with the problem rather than denying it existed.

In short, in the time since the Wollemi Pines were discovered, government agencies, nonprofit organisations, private enterprise and volunteer efforts successfully worked together over decades to protect the trees from extinction.

Which makes one wonder, once again, what we in the States could learn from observing the Australian experience. − Climate News Network

This story originally appeared in the Bulletin of the Atomic Scientists and is republished here as part of Covering Climate Now, a global journalism collaboration to strengthen coverage of the climate story.

Buried amid the horrific news from Australia about climate change and out-of-control wildfire was a positive story: the saving of rare trees.

CHICAGO, 5 February, 2020 − An Associated Press story  titled Firefighters in Australia save unique prehistoric trees brought a scarce gleam of hope: “Firefighters winched from helicopters to reach the cluster of fewer than 200 Wollemi Pines in a remote gorge in the Blue Mountains a week before a massive wildfire bore down… the firefighters set up an irrigation system to keep the so-called dinosaur trees moist, and pumped water daily from the gorge as the blaze that had burned out of control for two months edged closer.”

This news had particular significance to me for a number of reasons. For one thing, the successful protection of this endangered species could hint at things to come − if we play our cards right.

For another, I know the Blue Mountains of New South Wales (though I have not been to that grove of trees − whose exact location has been kept a secret by botanists ever since it was first discovered in 1994.)

I spent four years down-under, first as an American researcher on a Fulbright grant to see what we in the States could learn from looking at the Australian experience, and then as a roving foreign correspondent for science-related US magazines such as International Wildlife, Scientific American, and the journal Science, among others.

My job was to travel over the land down-under, reporting on natural history, the environment, and science in the Great South Land for publications back home in the States − as well as magazines like Australian Geographic.

Easy to miss

Which was how I became acquainted with the Blue Mountains, a lesser-known area about 120 miles west of Sydney. They’re a surprisingly steep, thickly wooded, and easily overlooked mountain chain, much like an Aussie version of our Appalachians. And much like the Appalachians, their deep ravines held up westward exploration and expansion for a long time. But there the parallels end.

Walking in Australia’s Blue Mountains is an unworldly experience. There are no squirrels or chipmunks; instead, parrots occupy that ecological niche. My edition of the Field Guide to the Birds of Australia lists 23 different species of parrots alone.

Just a short list of the formal names of some of the individual species gives an idea of the colorful diversity you can see: Blue-winged, Orange-bellied, Golden-shouldered, Scarlet-chested, Red-rumped, and Turquoise parrots. Not to mention Elegant, Paradise, Superb, and King parrots.

And instead of smelling pine trees, your nose registers the scent of eucalypts. Look up at the stars at night, and there’s not a single familiar constellation; instead you see celestial objects like the Jewel Box Cluster − while hearing the mocking laugh of kookaburras.

Even the food tastes different − in place of pepperoni or sausage, toppings at the Australian Pizza Kitchen in Canberra include emu and kangaroo (I prefer the kangaroo).

“These trees are descendants of individuals that had survived since the era of the dinosaurs”

And some of the trees in parts of the Blueys − as they’re called − resemble nothing so much as short stumps with ferns popping out of their sides willy-nilly; everything looks so primeval you half-expect to see escapees from Jurassic Park poking their snouts out.

Indeed, in far-north Queensland I and my parents were to be stalked by a full-grown, adult male cassowary, defending his mate. We took shelter behind a large tropical tree, trying to keep the trunk between us and the approximately 200-pound, 6-foot-tall creature as it circled around.

This pervasive feeling of encounters with the primeval is appropriate. Australia is a very ancient land, which used to be part of what geologists call Gondwana − when most of the world’s landmasses were linked together in the distant past.

But while the other landforms went on to become continents such as South America and Africa, Australia remained a giant island continent, cut off from the rest of the planet. And species that died out elsewhere continued to thrive, and evolve, here.

(Just why species do so well on islands, and why evolution seems to speed up on them, is something that kept Charles Darwin busy. An entire field of island biogeography has sprung up to delve into its mysteries.)

Human rarities

Even now, some parts of Australia are so isolated that the wildlife has seldom seen humans. So far as researchers can tell, no Aborigines, Melanesians, Micronesians, Polynesians, or Caucasians ever settled on Australia’s Lord Howe Island until 1834; consequently, the wildlife never learned to be afraid of humans.

When I went there, you could stand at the foot of Lord Howe’s tallest mountain, call up to the providence petrels nesting as much as a hundred feet above, and watch the birds glide down to land at your feet. If you’re really good, you may be able to touch them, or at least have one land on your outstretched arm.

Due to these vagaries of isolation, ancient and unique species seem to abound in Australia − though they can be easily overlooked. Drive along the highway outside Shark Bay in the state of Western Australia, and you’ll spot weird dark, mushroom-shaped, rock-like structures in the shallows of the hyper-salty water; they’re actually living mats of blue-green algae known as stromatolites − Greek for “layered rock.”

Stromatolites are one of the oldest forms of life that we know of, essentially unchanged since their ancestors flourished 3.5 billion years ago. They were previously known to us only from fossils, until first discovered in this region in the 1980s.

So it’s not entirely surprising that Wollemi Pines should survive in the wild, undetected, a relatively short drive from Sydney for so many years; after all, these trees are descendants of individuals that had survived since the era of the dinosaurs − though they now exist in the wild in only one place in the world, with fewer than 100 adult specimens known.

Survivors for sale

What was surprising was that these wild specimens were saved from the wildfires, in a complex operation that involved firefighters being lowered from helicopters into the narrow steep-sided ridges where the trees dwell, along with planes strategically bombing the advancing firefront with fire retardant.

And well in advance of events these past months, authorities had covered their bets by doing all they could to increase the species’ chance of survival. Since 2006, a propagation program has made these trees available to botanical gardens so their numbers could be increased; I’ve subsequently run across Aussies who have grown the plants from seeds in their living rooms. (In Australia, seedlings can even be ordered online,  and the Royal Botanic Gardens Sydney offer information on Wollemi care, conservation, and research.)

More than that, when it looked like the wildfires were in imminent danger of destroying the only existing stand of these trees in the wild, leaders had the foresight to rely on the recommendations of scientists, firefighters, and other experts as to how to proceed. They then worked out a plan and put it into action − actively dealing with the problem rather than denying it existed.

In short, in the time since the Wollemi Pines were discovered, government agencies, nonprofit organisations, private enterprise and volunteer efforts successfully worked together over decades to protect the trees from extinction.

Which makes one wonder, once again, what we in the States could learn from observing the Australian experience. − Climate News Network