Tag Archives: Human health

Paris treaty would cut US heat peril

Even in rich, air-conditioned America, people die in extreme heat. This US heat peril means more will die. Political decisions will decide how many more.

LONDON, 18 June, 2019 − British scientists have identified a way in which President Trump could save thousands of American lives from the US heat peril. All he needs to do is honour the Paris Agreement of 2015 to keep global warming to “well below” 2°C above the planetary average that has endured for most of human history.

If the global thermometer is kept at the lowest possible level of a rise of 1.5°C – rather than the average rise of 3°C of human-triggered heating that the planet seems on course to experience by the end of the century − then this simple decision would prevent up to 2,720 extra deaths in any city that experienced the kind of potentially-deadly heatwave that comes along every thirty years or so, according to a new study in the journal Scientific Advances.

Researchers focused on 15 US cities from where records yielded reliable data that could answer questions about climate and health. These were Atlanta, Boston, Chicago, Dallas, Detroit, Houston, Los Angeles, Miami, New York City, Philadelphia, Phoenix, San Francisco, Seattle, St Louis and Washington DC.

They then used statistical tools to calculate the number of deaths that could be expected in the kind of extremely hot summers occasionally recorded in big cities at almost any latitude, and likely to recur with greater frequency and intensity as global average temperatures rise.

Poor face biggest risk

They found what they call “compelling evidence” that limiting global warming to 1.5°C would prevent significantly more excess deaths among the old, the poor or the already-ill in the US than a 2°C limit, and many more than the 3°C or more if governments continue on a “business as usual” course and humans burn even more fossil fuels, to emit ever more greenhouse gases into the atmosphere.

President Trump has promised to withdraw the US from the Paris Agreement signed by his predecessor, President Obama. But the study is a reminder that extremes of heat bring often devastating losses of life even in relatively well-off communities in the world’s temperate zones. Those most at risk remain the poorest urban dwellers in the world’s warmest places.

Researchers have warned that by 2100, one person in three in Africa’s cities could be exposed to intolerable levels of heat, and have identified other zones where heat and humidity could conspire to reach lethal levels: these include the North China plain and the Gulf region.

US scientists recently numbered 27 ways in which extremes of heat could claim lives and some of these are likely to apply to cities in the normally cooler parts of the globe.

“Limiting global warming to 1.5°C would prevent significantly more excess deaths among the old, the poor or the already-ill in the US than a 2°C limit”

Health authorities have identified deaths attributable to heat in London and Paris in 2003, and European scientists have warned that more murderous heat waves are on the way.

And although the Science Advances research concentrates on what could happen in American cities tomorrow, a second and separate study led by US scientists has just established a direct link between intense heat events and extra deaths in the Nevada city of Las Vegas, just in the last 10 years.

They report in the International Journal of Environmental Science and Technology that they found a steady increase in the severity and frequency of excess heat in the city since 1980, and a matching increase in numbers of deaths.

Between 2007 and 2016, there were 437 heat-related deaths in the city, with the greatest number in 2016, the year of the highest measures of heat for the past 35 years. − Climate News Network

Even in rich, air-conditioned America, people die in extreme heat. This US heat peril means more will die. Political decisions will decide how many more.

LONDON, 18 June, 2019 − British scientists have identified a way in which President Trump could save thousands of American lives from the US heat peril. All he needs to do is honour the Paris Agreement of 2015 to keep global warming to “well below” 2°C above the planetary average that has endured for most of human history.

If the global thermometer is kept at the lowest possible level of a rise of 1.5°C – rather than the average rise of 3°C of human-triggered heating that the planet seems on course to experience by the end of the century − then this simple decision would prevent up to 2,720 extra deaths in any city that experienced the kind of potentially-deadly heatwave that comes along every thirty years or so, according to a new study in the journal Scientific Advances.

Researchers focused on 15 US cities from where records yielded reliable data that could answer questions about climate and health. These were Atlanta, Boston, Chicago, Dallas, Detroit, Houston, Los Angeles, Miami, New York City, Philadelphia, Phoenix, San Francisco, Seattle, St Louis and Washington DC.

They then used statistical tools to calculate the number of deaths that could be expected in the kind of extremely hot summers occasionally recorded in big cities at almost any latitude, and likely to recur with greater frequency and intensity as global average temperatures rise.

Poor face biggest risk

They found what they call “compelling evidence” that limiting global warming to 1.5°C would prevent significantly more excess deaths among the old, the poor or the already-ill in the US than a 2°C limit, and many more than the 3°C or more if governments continue on a “business as usual” course and humans burn even more fossil fuels, to emit ever more greenhouse gases into the atmosphere.

President Trump has promised to withdraw the US from the Paris Agreement signed by his predecessor, President Obama. But the study is a reminder that extremes of heat bring often devastating losses of life even in relatively well-off communities in the world’s temperate zones. Those most at risk remain the poorest urban dwellers in the world’s warmest places.

Researchers have warned that by 2100, one person in three in Africa’s cities could be exposed to intolerable levels of heat, and have identified other zones where heat and humidity could conspire to reach lethal levels: these include the North China plain and the Gulf region.

US scientists recently numbered 27 ways in which extremes of heat could claim lives and some of these are likely to apply to cities in the normally cooler parts of the globe.

“Limiting global warming to 1.5°C would prevent significantly more excess deaths among the old, the poor or the already-ill in the US than a 2°C limit”

Health authorities have identified deaths attributable to heat in London and Paris in 2003, and European scientists have warned that more murderous heat waves are on the way.

And although the Science Advances research concentrates on what could happen in American cities tomorrow, a second and separate study led by US scientists has just established a direct link between intense heat events and extra deaths in the Nevada city of Las Vegas, just in the last 10 years.

They report in the International Journal of Environmental Science and Technology that they found a steady increase in the severity and frequency of excess heat in the city since 1980, and a matching increase in numbers of deaths.

Between 2007 and 2016, there were 437 heat-related deaths in the city, with the greatest number in 2016, the year of the highest measures of heat for the past 35 years. − Climate News Network

Climate crisis raises risk of conflict

A warmer world will be more dangerous. As the thermometer rises, so does the risk of conflict and bloodshed in more vulnerable regions.

LONDON, 14 June, 2019 − If the world warms by 4°C this century, the climate factor becomes more dangerous – five times more dangerous, according to new research, which predicts a 26% increase in the risk of conflict, just because of climate change.

Even if the world sticks to a promise made in Paris in 2015, when 195 nations vowed to contain global warming to “well below” 2°C above pre-industrial levels by the end of the century, the impact of climate on the risk of armed conflict will double. The risk will rise to 13%.

US researchers report in the journal Nature that they quizzed a pool of 11 experts on climate and conflict from a range of disciplines. There is no consensus on the mechanism that links a shift in average temperatures and ethnic bitterness, migration, violence and outright civil war within any single nation. But there is a simple conclusion: whatever the process, climate change raises the risk of conflict.

And the study comes just as the latest publication of the  Global Peace Index warns that 971 million people now live in areas with what is termed high or “very high climate change exposure”, and 400 million of these people already live in countries with “low levels of peacefulness.”

Making conflict likelier

The Global Peace Index issues the same warning: that climate change can indirectly increase the likelihood of violent conflict by affecting the resources available to citizens, to jobs and careers, and by undermining security and forcing migration.

And, the same study says, this comes at a colossal economic cost. In 2018, the impact of violence on the global economy totalled $14.1 trillion in purchasing power. This is more than 11% of the world’s economic activity and adds up to $1,853 per person.

Both studies reinforce earlier research. Social scientists, geographers and statisticians have repeatedly found links between climate change and conflict, between climate change and migration, and have warned of more to come, specifically in South Asia, and worldwide.

“Over this century, unprecedented climate change is going to have significant impacts … but it is extremely hard to anticipate whether the political changes related to climate change will have big effects on armed conflict in turn”

There is a debate about the role of drought in the bloodshed in Syria, but there is less argument about the proposition that climate change unsettles what may already be nations or communities vulnerable to conflict.

There have also been bleak warnings from prehistory: archaeologists think that climate change may have been behind the collapse of the Bronze Age Mediterranean culture and the fall of an ancient Assyrian society.

The point of the latest study was simply to find some consensus on the risks of conflict in a world in climate crisis. The theorists think that climate stresses over the last century have already influenced in some way between 3% and 20% of armed conflict risk.

They think the risks could increase dramatically, as normally productive agricultural regions face catastrophic crop failure, as extremes of temperature make crowded cities more dangerous, as people are driven off their land by sustained drought, and as climate impacts impoverish the already vulnerable, to increase global levels of injustice and inequality.

Planning protection

Armed with a sense of the scale of the future hazard, governments and international agencies could equip themselves with strategies that might help to increase global food security and provide other economic opportunities. Peacekeeping forces and aid agencies need to understand, too, that climate factors are, increasingly, part of the risk.

“Historically, levels of armed conflict over time have been heavily influenced by shocks to, and changes in, international relations among states and in their domestic political systems,” said James Fearon, a political scientist at Stanford University and one of the authors.

“It is quite likely that, over this century, unprecedented climate change is going to have significant impacts on both, but it is extremely hard to anticipate whether the political changes related to climate change will have big effects on armed conflict in turn. So I think putting non-trivial weight on significant climate effects on conflict is reasonable.” − Climate News Network

A warmer world will be more dangerous. As the thermometer rises, so does the risk of conflict and bloodshed in more vulnerable regions.

LONDON, 14 June, 2019 − If the world warms by 4°C this century, the climate factor becomes more dangerous – five times more dangerous, according to new research, which predicts a 26% increase in the risk of conflict, just because of climate change.

Even if the world sticks to a promise made in Paris in 2015, when 195 nations vowed to contain global warming to “well below” 2°C above pre-industrial levels by the end of the century, the impact of climate on the risk of armed conflict will double. The risk will rise to 13%.

US researchers report in the journal Nature that they quizzed a pool of 11 experts on climate and conflict from a range of disciplines. There is no consensus on the mechanism that links a shift in average temperatures and ethnic bitterness, migration, violence and outright civil war within any single nation. But there is a simple conclusion: whatever the process, climate change raises the risk of conflict.

And the study comes just as the latest publication of the  Global Peace Index warns that 971 million people now live in areas with what is termed high or “very high climate change exposure”, and 400 million of these people already live in countries with “low levels of peacefulness.”

Making conflict likelier

The Global Peace Index issues the same warning: that climate change can indirectly increase the likelihood of violent conflict by affecting the resources available to citizens, to jobs and careers, and by undermining security and forcing migration.

And, the same study says, this comes at a colossal economic cost. In 2018, the impact of violence on the global economy totalled $14.1 trillion in purchasing power. This is more than 11% of the world’s economic activity and adds up to $1,853 per person.

Both studies reinforce earlier research. Social scientists, geographers and statisticians have repeatedly found links between climate change and conflict, between climate change and migration, and have warned of more to come, specifically in South Asia, and worldwide.

“Over this century, unprecedented climate change is going to have significant impacts … but it is extremely hard to anticipate whether the political changes related to climate change will have big effects on armed conflict in turn”

There is a debate about the role of drought in the bloodshed in Syria, but there is less argument about the proposition that climate change unsettles what may already be nations or communities vulnerable to conflict.

There have also been bleak warnings from prehistory: archaeologists think that climate change may have been behind the collapse of the Bronze Age Mediterranean culture and the fall of an ancient Assyrian society.

The point of the latest study was simply to find some consensus on the risks of conflict in a world in climate crisis. The theorists think that climate stresses over the last century have already influenced in some way between 3% and 20% of armed conflict risk.

They think the risks could increase dramatically, as normally productive agricultural regions face catastrophic crop failure, as extremes of temperature make crowded cities more dangerous, as people are driven off their land by sustained drought, and as climate impacts impoverish the already vulnerable, to increase global levels of injustice and inequality.

Planning protection

Armed with a sense of the scale of the future hazard, governments and international agencies could equip themselves with strategies that might help to increase global food security and provide other economic opportunities. Peacekeeping forces and aid agencies need to understand, too, that climate factors are, increasingly, part of the risk.

“Historically, levels of armed conflict over time have been heavily influenced by shocks to, and changes in, international relations among states and in their domestic political systems,” said James Fearon, a political scientist at Stanford University and one of the authors.

“It is quite likely that, over this century, unprecedented climate change is going to have significant impacts on both, but it is extremely hard to anticipate whether the political changes related to climate change will have big effects on armed conflict in turn. So I think putting non-trivial weight on significant climate effects on conflict is reasonable.” − Climate News Network

African city heat is set to grow intolerably

Up to a third of urban dwellers could soon face extreme African city heat and humidity. Risks could at worst multiply 50-fold.

LONDON, 11 June, 2019 – An entire continent faces lethal conditions for many of its people: by 2090, one person in three can expect African city heat in the great conurbations severe enough to expose them to potentially deadly temperatures.

That is: the number of days in which the apparent temperature – a notional balance of thermometer-measured heat and maximum humidity – could reach or surpass 40.6°C will increase dramatically, and the days when individuals could be at risk could in some scenarios multiply 50-fold.

The scientists selected this “apparent” temperature of 40.6°C because it is significantly beyond the natural temperature of the human body, which must then be kept cool by perspiration. This is possible in arid climates.

But as humidity goes up – and with each 1°C rise in temperature, the capacity of the air to hold moisture rises by 7% – cooling by perspiration becomes less efficient.

So at this notionally-defined apparent temperature, people who cannot retreat to air-conditioned or cooler, shadier places could die. Heat kills: researchers recently counted 27 ways in which extreme temperatures could claim lives.

“If we follow the Paris Agreement, we’ll halve the number of people at risk in 2090, which is encouraging”

And more, and more intense and prolonged heat waves are on the way, and with them episodes of potentially extreme humidity. By 2100, according to some studies, certain regions of the planet could become dangerous habitat.

European scientists report in the journal Earth’s Future that they considered the hazard for just one, rapidly-growing continent: Africa. They selected 173 cities of more than 300,000 people in 43 nations across a range of climates, from Algiers on the Mediterranean to the burgeoning monsoon cities of the equatorial west coast, such as Lagos and Kinshasa, the drier east African states, and the relatively mild townships of Southern Africa.

They then considered how much cities might grow, by migration or birth-rate increases, and how they might develop. Then they factored in a range of climate scenarios and looked at possible forecasts for the years 2030, 2060 and 2090.

They found that because of population growth, the numbers of days on which people could be at risk – measured in person-days (one person working for one full day) – would in any case increase.

Sharper rise

“In the best case, 20 billion person-days will be affected by 2030, compared with 4.2bn in 2010 – a jump, in other words, of 376%” said Guillaume Rohat, of the University of Geneva, who led the study. “This figure climbs to 45bn in 2060 (up 971%) and reaches 86bn in 2090 (up 1947%).

And that is the best-case scenario. When the researchers factored in the steepest population increases, the most rapid growth of the cities and the worst disturbances in climate, the figures rose more sharply. By 2030, 26 billion, a fivefold increase, could be at risk, 95bn in 2060 and 217 bn in 2090. This is an increase of 4967%, or nearly 50-fold.

The researchers assumed that not everybody in their 173 cities would be exposed to dangerous levels of heat. Were that to happen, the number of person-days could hit 647 billion. But the researchers made a conservative estimate of one in three people who would be exposed to a minimum temperature of 40.6°C.

Research of this kind makes assumptions about how the climate is going to change, and separately about how nations are going to develop, how populations are going to grow and change, and how governments are going to respond to the climate emergency, and the authors recognise the problems.

Conservative conclusions

The sample is biased towards the larger cities. Their calculations don’t include predictions for capital investment. But the researchers say their conclusions are if anything conservative. They do not, for instance, factor in the notorious urban heat island effect that tends to make cities 3°C or more hotter than the surrounding countryside, and therefore even more dangerous.

The good news to emerge from the study is that concerted action, by governments and civic authorities, can reduce the risk. Were nations to stick to an agreement made by 195 of them in Paris in 2015, and keep global temperature rise to “well below” 2°C, the final exposure hazard would be reduced by 48%.

“This proves that if we follow the Paris Agreement, we’ll halve the number of people at risk in 2090, which is encouraging,” said Rohat.

“We can see the importance of the UN Sustainable Development Goals: access to education, a drop in the number of children per woman, developments in the standard of living and so on.” – Climate News Network

Up to a third of urban dwellers could soon face extreme African city heat and humidity. Risks could at worst multiply 50-fold.

LONDON, 11 June, 2019 – An entire continent faces lethal conditions for many of its people: by 2090, one person in three can expect African city heat in the great conurbations severe enough to expose them to potentially deadly temperatures.

That is: the number of days in which the apparent temperature – a notional balance of thermometer-measured heat and maximum humidity – could reach or surpass 40.6°C will increase dramatically, and the days when individuals could be at risk could in some scenarios multiply 50-fold.

The scientists selected this “apparent” temperature of 40.6°C because it is significantly beyond the natural temperature of the human body, which must then be kept cool by perspiration. This is possible in arid climates.

But as humidity goes up – and with each 1°C rise in temperature, the capacity of the air to hold moisture rises by 7% – cooling by perspiration becomes less efficient.

So at this notionally-defined apparent temperature, people who cannot retreat to air-conditioned or cooler, shadier places could die. Heat kills: researchers recently counted 27 ways in which extreme temperatures could claim lives.

“If we follow the Paris Agreement, we’ll halve the number of people at risk in 2090, which is encouraging”

And more, and more intense and prolonged heat waves are on the way, and with them episodes of potentially extreme humidity. By 2100, according to some studies, certain regions of the planet could become dangerous habitat.

European scientists report in the journal Earth’s Future that they considered the hazard for just one, rapidly-growing continent: Africa. They selected 173 cities of more than 300,000 people in 43 nations across a range of climates, from Algiers on the Mediterranean to the burgeoning monsoon cities of the equatorial west coast, such as Lagos and Kinshasa, the drier east African states, and the relatively mild townships of Southern Africa.

They then considered how much cities might grow, by migration or birth-rate increases, and how they might develop. Then they factored in a range of climate scenarios and looked at possible forecasts for the years 2030, 2060 and 2090.

They found that because of population growth, the numbers of days on which people could be at risk – measured in person-days (one person working for one full day) – would in any case increase.

Sharper rise

“In the best case, 20 billion person-days will be affected by 2030, compared with 4.2bn in 2010 – a jump, in other words, of 376%” said Guillaume Rohat, of the University of Geneva, who led the study. “This figure climbs to 45bn in 2060 (up 971%) and reaches 86bn in 2090 (up 1947%).

And that is the best-case scenario. When the researchers factored in the steepest population increases, the most rapid growth of the cities and the worst disturbances in climate, the figures rose more sharply. By 2030, 26 billion, a fivefold increase, could be at risk, 95bn in 2060 and 217 bn in 2090. This is an increase of 4967%, or nearly 50-fold.

The researchers assumed that not everybody in their 173 cities would be exposed to dangerous levels of heat. Were that to happen, the number of person-days could hit 647 billion. But the researchers made a conservative estimate of one in three people who would be exposed to a minimum temperature of 40.6°C.

Research of this kind makes assumptions about how the climate is going to change, and separately about how nations are going to develop, how populations are going to grow and change, and how governments are going to respond to the climate emergency, and the authors recognise the problems.

Conservative conclusions

The sample is biased towards the larger cities. Their calculations don’t include predictions for capital investment. But the researchers say their conclusions are if anything conservative. They do not, for instance, factor in the notorious urban heat island effect that tends to make cities 3°C or more hotter than the surrounding countryside, and therefore even more dangerous.

The good news to emerge from the study is that concerted action, by governments and civic authorities, can reduce the risk. Were nations to stick to an agreement made by 195 of them in Paris in 2015, and keep global temperature rise to “well below” 2°C, the final exposure hazard would be reduced by 48%.

“This proves that if we follow the Paris Agreement, we’ll halve the number of people at risk in 2090, which is encouraging,” said Rohat.

“We can see the importance of the UN Sustainable Development Goals: access to education, a drop in the number of children per woman, developments in the standard of living and so on.” – Climate News Network

Thirty years to climate meltdown – or not?

For years most of us largely ignored the idea of climate meltdown. Now we’re talking about it. So what should we be doing?

LONDON, 10 June, 2019 − How much of a threat is climate meltdown? Should we treat it as the biggest danger to life in the 21st century, or as one of many problems − serious, but manageable?

A new study says human civilisation itself could pass the point of no return by 2050. The Australian climate think-tank Breakthrough: National Centre for Climate Restoration says that unless humanity takes drastic and immediate action to save the climate, a combination of unstable food production, water shortages and extreme weather could lead to the breakdown of global society.

One renowned US climate scientist, Michael Mann of Pennsylvania State University, says that Breakthrough is exaggerating and its report could be counter-productive.

In the UK, though, Mark Maslin of University College London says the report underlines the deep concerns expressed by some security experts.

Act together

Chris Barrie, a retired Royal Australian Navy admiral and former Chief of the Australian Defence Force, is now an honorary professor at the Australian National University, Canberra.

In a foreword to the Breakthrough study he writes: “We must act collectively. We need strong, determined leadership in government, in business and in our communities to ensure a sustainable future for humankind.”

David Spratt, Breakthrough’s research director and a co-author of the study, says that “much knowledge produced for policymakers is too conservative,” but that the new paper, by showing the extreme end of what could happen in just the next three decades, aims to make the stakes clear. “The report speaks, in our opinion, a harsh but necessary truth,” he says.

“To reduce this risk and protect human civilisation, a massive global mobilisation of resources is needed in the coming decade to build a zero-emissions industrial system and set in train the restoration of a safe climate,” the report reads. “This would be akin in scale to the World War II emergency mobilisation.”

“Maybe, just maybe, it is time for our politicians to be worried and start to act to avoid the scenarios painted so vividly”

Breakthrough acknowledges that the worst possibility it foresees − the total collapse of civilisation by mid-century − is an example of a worst-case scenario, but it insists that “the world is currently completely unprepared to envisage, and even less deal with, the consequences of catastrophic climate change.”

The picture of the possible near future it presents is stark. By 2050, it says, the world could have reached:

  • a 3°C temperature rise, with a further 1°C in store
  • sea levels 0.5 metres above today’s, with a possible eventual rise of 25m
  • 55% of the world’s people subject to more than 20 days a year of heat “beyond the threshold of human survivability”
  • one billion people forced to leave the tropics
  • a 20% decline in crop yields, leaving too little food to feed the world
  • armed conflict likely and nuclear war possible.

The report’s authors conclude: “The scale of destruction is beyond our capacity to model, with a high likelihood of human civilisation coming to an end.”

Warnings examined

Warnings of the possible end of human civilisation are not new. They range from those which offer highly-qualified hope for humanity’s future to others which find very little to celebrate, even tentatively.

The Breakthrough study fits unequivocally into the second group. To weigh the credibility of some of its statements, the journal New Scientist looks at the sources they cite and the wider context of the claims they make.

Its scrutiny ends with the views of two eminent climate scientists. Michael Mann, professor of atmospheric science at Penn State, says: “I respect the authors and appreciate that their intentions are good, but … overblown rhetoric, exaggeration, and unsupportable doomist framing can be counteractive to climate action.”

For his part, Mark Maslin, professor of geography at UCL, tells New Scientist that the Breakthrough report adds to the deep concerns expressed by security experts such as the Pentagon over climate change.

Hope nurtured

“Maybe, just maybe, it is time for our politicians to be worried and start to act to avoid the scenarios painted so vividly,” he says.

The 2020 round of UN climate negotiations is due to take place in November next year, with hopes building that many countries will agree then to make much more radical cuts in greenhouse gas emissions than they have pledged so far.

Altogether 195 countries promised in 2015, in the Paris Agreement, to make the cuts needed to prevent global average temperatures rising more than 2°C, and if possible to stay below a maximum rise of 1.5°C, the levels climate scientists say are the highest that can assure the planet’s safety. But the cuts that many countries have promised so far will not achieve either goal.

Scientists say it is still possible for the world to achieve the 1.5°C limit. But doing so requires immediate emissions cuts, on a scale and at a pace that are not yet in sight − “a very big ‘if’”, as one of them put it. − Climate News Network

For years most of us largely ignored the idea of climate meltdown. Now we’re talking about it. So what should we be doing?

LONDON, 10 June, 2019 − How much of a threat is climate meltdown? Should we treat it as the biggest danger to life in the 21st century, or as one of many problems − serious, but manageable?

A new study says human civilisation itself could pass the point of no return by 2050. The Australian climate think-tank Breakthrough: National Centre for Climate Restoration says that unless humanity takes drastic and immediate action to save the climate, a combination of unstable food production, water shortages and extreme weather could lead to the breakdown of global society.

One renowned US climate scientist, Michael Mann of Pennsylvania State University, says that Breakthrough is exaggerating and its report could be counter-productive.

In the UK, though, Mark Maslin of University College London says the report underlines the deep concerns expressed by some security experts.

Act together

Chris Barrie, a retired Royal Australian Navy admiral and former Chief of the Australian Defence Force, is now an honorary professor at the Australian National University, Canberra.

In a foreword to the Breakthrough study he writes: “We must act collectively. We need strong, determined leadership in government, in business and in our communities to ensure a sustainable future for humankind.”

David Spratt, Breakthrough’s research director and a co-author of the study, says that “much knowledge produced for policymakers is too conservative,” but that the new paper, by showing the extreme end of what could happen in just the next three decades, aims to make the stakes clear. “The report speaks, in our opinion, a harsh but necessary truth,” he says.

“To reduce this risk and protect human civilisation, a massive global mobilisation of resources is needed in the coming decade to build a zero-emissions industrial system and set in train the restoration of a safe climate,” the report reads. “This would be akin in scale to the World War II emergency mobilisation.”

“Maybe, just maybe, it is time for our politicians to be worried and start to act to avoid the scenarios painted so vividly”

Breakthrough acknowledges that the worst possibility it foresees − the total collapse of civilisation by mid-century − is an example of a worst-case scenario, but it insists that “the world is currently completely unprepared to envisage, and even less deal with, the consequences of catastrophic climate change.”

The picture of the possible near future it presents is stark. By 2050, it says, the world could have reached:

  • a 3°C temperature rise, with a further 1°C in store
  • sea levels 0.5 metres above today’s, with a possible eventual rise of 25m
  • 55% of the world’s people subject to more than 20 days a year of heat “beyond the threshold of human survivability”
  • one billion people forced to leave the tropics
  • a 20% decline in crop yields, leaving too little food to feed the world
  • armed conflict likely and nuclear war possible.

The report’s authors conclude: “The scale of destruction is beyond our capacity to model, with a high likelihood of human civilisation coming to an end.”

Warnings examined

Warnings of the possible end of human civilisation are not new. They range from those which offer highly-qualified hope for humanity’s future to others which find very little to celebrate, even tentatively.

The Breakthrough study fits unequivocally into the second group. To weigh the credibility of some of its statements, the journal New Scientist looks at the sources they cite and the wider context of the claims they make.

Its scrutiny ends with the views of two eminent climate scientists. Michael Mann, professor of atmospheric science at Penn State, says: “I respect the authors and appreciate that their intentions are good, but … overblown rhetoric, exaggeration, and unsupportable doomist framing can be counteractive to climate action.”

For his part, Mark Maslin, professor of geography at UCL, tells New Scientist that the Breakthrough report adds to the deep concerns expressed by security experts such as the Pentagon over climate change.

Hope nurtured

“Maybe, just maybe, it is time for our politicians to be worried and start to act to avoid the scenarios painted so vividly,” he says.

The 2020 round of UN climate negotiations is due to take place in November next year, with hopes building that many countries will agree then to make much more radical cuts in greenhouse gas emissions than they have pledged so far.

Altogether 195 countries promised in 2015, in the Paris Agreement, to make the cuts needed to prevent global average temperatures rising more than 2°C, and if possible to stay below a maximum rise of 1.5°C, the levels climate scientists say are the highest that can assure the planet’s safety. But the cuts that many countries have promised so far will not achieve either goal.

Scientists say it is still possible for the world to achieve the 1.5°C limit. But doing so requires immediate emissions cuts, on a scale and at a pace that are not yet in sight − “a very big ‘if’”, as one of them put it. − Climate News Network

Political lobbying buys off climate law

When it comes to influence, big bucks are hard to beat. Climate campaigners can learn from a study of US political lobbying.

LONDON, 4 June, 2019 − Big money talks loudest. A decade ago Washington saw political lobbying spend $700 million to influence the political shape and progress of the American Clean Energy and Security Act – and significantly reduce its chances of success.

The reward for the investment was a 13% reduction in its chances of progress into law. The pay-off for the rest of humanity was, at a conservative estimate, an extra $60 billion worth of climate damages from future superstorms, droughts and heatwaves associated with global heating.

The political initiative was at the time the most prominent and promising US climate regulation legislation so far on the books. It failed.

“The popular media widely postulated at the time that oppositional political interests played a key role in the bill’s demise,” say two US scientists in the journal Nature Climate Change.

“If valid, this points to lobbying as an explanation for why so few climate change regulations are enacted. It also provides an example in which lobbying had welfare consequences by reducing the likelihood of enacting a socially beneficial policy.”

“There is increasing concern that this lack of climate action may be due to political influences”

That political persuaders, funded ultimately by the fossil fuel industries or think-tanks and associations that act for them, can affect the political process is not news. Research has at least twice linked the strident voice of climate denial with very big corporations or unexplained sources of funding.

And the lobby industry in Washington has been linked with systematic attempts to muddy or cast doubt upon the science that now comprehensively supports evidence of human-triggered and potentially catastrophic climate change.

Since then, President Trump has announced that the US will withdraw from the Paris Agreement, backed in 2015 by 195 nations, and the US Department of Energy has started to rebrand the potent greenhouse gas methane as the “freedom molecule” in a bid to give an exported fossil fuel a more wholesome reputation.

“There has been a striking disconnect between what is needed to avoid dangerous climate change and what has actually been done to date,” said Kyle Meng, of the University of Southern California at Santa Barbara, who led the study. “There is increasing concern that this lack of climate action may be due to political influences.”

But all political decisions involve compromise and there are many reasons why legislation can fail. Dr Meng and his co-author played statistical games with the available evidence to make calculations of the chances of success for the so-called 2009-2010 Waxman-Markey Bill that would have become the American Clean Energy and Security Act had it been passed.

Reduced chances

They made judgements about how successful legislation would affect the stock prices of businesses that were involved in lobbying congress and senate. They calculated that the bill had about a 55% chance of adoption, and used available data to calculate that big business which might have been affected by the bill in various ways spent $700 million on trying to influence the politicians.

And they found that lobbying by corporations that might expect to lose was more effective than lobbying by those businesses that might gain from successful legislation, and in effect reduced the bill’s chances of success to 42%.

They then used the same statistical logic to set a total for the extra “social cost” of greenhouse gases in terms of damage to human health, agriculture, insurance costs and so on: a total, they calculate, of $60bn at 2018 prices.

There are always problems with this kind of “what if?” or counter-factual research, and the authors concede the need for caution. But they argue that lessons can be learned about the way such legislation should be drawn up in the first place.

“Our findings also provide a glimmer of hope by paving a path toward politically more robust climate policies,” Dr Meng said. “Subtle design changes to market-based climate policies can alleviate political opposition and increase chances of adoption.” − Climate News Network

When it comes to influence, big bucks are hard to beat. Climate campaigners can learn from a study of US political lobbying.

LONDON, 4 June, 2019 − Big money talks loudest. A decade ago Washington saw political lobbying spend $700 million to influence the political shape and progress of the American Clean Energy and Security Act – and significantly reduce its chances of success.

The reward for the investment was a 13% reduction in its chances of progress into law. The pay-off for the rest of humanity was, at a conservative estimate, an extra $60 billion worth of climate damages from future superstorms, droughts and heatwaves associated with global heating.

The political initiative was at the time the most prominent and promising US climate regulation legislation so far on the books. It failed.

“The popular media widely postulated at the time that oppositional political interests played a key role in the bill’s demise,” say two US scientists in the journal Nature Climate Change.

“If valid, this points to lobbying as an explanation for why so few climate change regulations are enacted. It also provides an example in which lobbying had welfare consequences by reducing the likelihood of enacting a socially beneficial policy.”

“There is increasing concern that this lack of climate action may be due to political influences”

That political persuaders, funded ultimately by the fossil fuel industries or think-tanks and associations that act for them, can affect the political process is not news. Research has at least twice linked the strident voice of climate denial with very big corporations or unexplained sources of funding.

And the lobby industry in Washington has been linked with systematic attempts to muddy or cast doubt upon the science that now comprehensively supports evidence of human-triggered and potentially catastrophic climate change.

Since then, President Trump has announced that the US will withdraw from the Paris Agreement, backed in 2015 by 195 nations, and the US Department of Energy has started to rebrand the potent greenhouse gas methane as the “freedom molecule” in a bid to give an exported fossil fuel a more wholesome reputation.

“There has been a striking disconnect between what is needed to avoid dangerous climate change and what has actually been done to date,” said Kyle Meng, of the University of Southern California at Santa Barbara, who led the study. “There is increasing concern that this lack of climate action may be due to political influences.”

But all political decisions involve compromise and there are many reasons why legislation can fail. Dr Meng and his co-author played statistical games with the available evidence to make calculations of the chances of success for the so-called 2009-2010 Waxman-Markey Bill that would have become the American Clean Energy and Security Act had it been passed.

Reduced chances

They made judgements about how successful legislation would affect the stock prices of businesses that were involved in lobbying congress and senate. They calculated that the bill had about a 55% chance of adoption, and used available data to calculate that big business which might have been affected by the bill in various ways spent $700 million on trying to influence the politicians.

And they found that lobbying by corporations that might expect to lose was more effective than lobbying by those businesses that might gain from successful legislation, and in effect reduced the bill’s chances of success to 42%.

They then used the same statistical logic to set a total for the extra “social cost” of greenhouse gases in terms of damage to human health, agriculture, insurance costs and so on: a total, they calculate, of $60bn at 2018 prices.

There are always problems with this kind of “what if?” or counter-factual research, and the authors concede the need for caution. But they argue that lessons can be learned about the way such legislation should be drawn up in the first place.

“Our findings also provide a glimmer of hope by paving a path toward politically more robust climate policies,” Dr Meng said. “Subtle design changes to market-based climate policies can alleviate political opposition and increase chances of adoption.” − Climate News Network

Compound heat waves have double impact

And now, a new climate hazard: compound heat waves. US scientists on a double whammy: rising mercury, followed swiftly by more of the same.

LONDON, 3 June, 2019 – Be ready for climate hazard in a new form – the compound heat waves that hit you, leave you, and come back again.

As the world warms, say US scientists, the risk of economically devastating, physically debilitating and potentially lethal extremes of heat will multiply, and in unexpected ways.

Researchers picture a world in which the most vulnerable – those already ill or elderly, housed in substandard buildings in crowded cities – are laid low and gasping by several days of extreme heat. Even if the temperatures drop a little, the buildings in which they live will still “store” heat to intolerable levels.

And then, unexpectedly, the extremes of heat return. Hospitals could be overwhelmed. Electric grids might experience overload. Harvests could wither. And the weakest could dehydrate and die.

“Averaged over time, heat waves are the most deadly type of disaster in the United States, in addition to causing many emergency room visits, lost working hours and lower agricultural yields,” said Jane Baldwin of Princeton University in the US.

“Surveys of low income housing in places such as Harlem have found that after a heat wave has ended, temperatures indoors can remain elevated”

“However, if you look at the deadliest heat waves in Europe and the United States, many have more unusual temporal structures with temperature jumping above and below extremely hot levels multiple times.”

Climate scientists have repeatedly warned that as the planet warms overall, the number of places where potentially deadly heat waves will hit will inevitably rise.

If humans go on burning fossil fuels at ever-increasing levels, then heat waves usually experienced once a century could return every few years, to become the “new normal.”

By 2100, most people on the planet could be at risk some of the time as heat extremes become more severe, and more frequent.

In some parts of the world, the combination of high humidity and high temperature really could kill after a few hours, and new research has started to assess the probability of potential famine, simply because devastating extremes of heat could endanger crop yields on two continents in the same year.

Gauging probabilities

Heat extremes can kill – the 2010 heat wave in Russia is estimated to have caused around 56,000 extra deaths – and US scientists recently counted 27 ways that sweltering heat can claim lives and devastate families.

The Princeton study, in the journal Earth’s Future, is a preliminary look simply at the probabilities of back-to-back heatwaves. Policymakers, city authorities and medical chiefs need to know what new hazards global heating can bring, and the study is, the scientists say, just a first step.

But it identifies the precise problems that come with severe temperatures, especially for the already vulnerable, even in the world’s richest cities, such as New York.

“Surveys of low income housing in places such as Harlem have found that after a heat wave has ended, temperatures indoors can remain elevated for a number of days,” Dr Baldwin said. A swift return of the big heat could multiply the stresses.

And her co-author Michael Oppenheimer said: “We want to know how the effects of compound heat waves will differ from – and amplify – the already severe consequences for human health, infrastructure stability and crop yield that we see from single event heat waves.” – Climate News Network

And now, a new climate hazard: compound heat waves. US scientists on a double whammy: rising mercury, followed swiftly by more of the same.

LONDON, 3 June, 2019 – Be ready for climate hazard in a new form – the compound heat waves that hit you, leave you, and come back again.

As the world warms, say US scientists, the risk of economically devastating, physically debilitating and potentially lethal extremes of heat will multiply, and in unexpected ways.

Researchers picture a world in which the most vulnerable – those already ill or elderly, housed in substandard buildings in crowded cities – are laid low and gasping by several days of extreme heat. Even if the temperatures drop a little, the buildings in which they live will still “store” heat to intolerable levels.

And then, unexpectedly, the extremes of heat return. Hospitals could be overwhelmed. Electric grids might experience overload. Harvests could wither. And the weakest could dehydrate and die.

“Averaged over time, heat waves are the most deadly type of disaster in the United States, in addition to causing many emergency room visits, lost working hours and lower agricultural yields,” said Jane Baldwin of Princeton University in the US.

“Surveys of low income housing in places such as Harlem have found that after a heat wave has ended, temperatures indoors can remain elevated”

“However, if you look at the deadliest heat waves in Europe and the United States, many have more unusual temporal structures with temperature jumping above and below extremely hot levels multiple times.”

Climate scientists have repeatedly warned that as the planet warms overall, the number of places where potentially deadly heat waves will hit will inevitably rise.

If humans go on burning fossil fuels at ever-increasing levels, then heat waves usually experienced once a century could return every few years, to become the “new normal.”

By 2100, most people on the planet could be at risk some of the time as heat extremes become more severe, and more frequent.

In some parts of the world, the combination of high humidity and high temperature really could kill after a few hours, and new research has started to assess the probability of potential famine, simply because devastating extremes of heat could endanger crop yields on two continents in the same year.

Gauging probabilities

Heat extremes can kill – the 2010 heat wave in Russia is estimated to have caused around 56,000 extra deaths – and US scientists recently counted 27 ways that sweltering heat can claim lives and devastate families.

The Princeton study, in the journal Earth’s Future, is a preliminary look simply at the probabilities of back-to-back heatwaves. Policymakers, city authorities and medical chiefs need to know what new hazards global heating can bring, and the study is, the scientists say, just a first step.

But it identifies the precise problems that come with severe temperatures, especially for the already vulnerable, even in the world’s richest cities, such as New York.

“Surveys of low income housing in places such as Harlem have found that after a heat wave has ended, temperatures indoors can remain elevated for a number of days,” Dr Baldwin said. A swift return of the big heat could multiply the stresses.

And her co-author Michael Oppenheimer said: “We want to know how the effects of compound heat waves will differ from – and amplify – the already severe consequences for human health, infrastructure stability and crop yield that we see from single event heat waves.” – Climate News Network

Humans drive sixth mass extinction wave

For the sixth time since life on Earth began, scientists say, mass extinction is a threat. This time, though, is different. The cause is us.

LONDON, 7 May, 2019 − About one million of the world’s animal and plant species are now at risk of extinction − the largest number in human history ever to be facing the threat of oblivion, scientists say. Many species could be wiped out within decades. And their plight is caused by humans, and will inevitably affect us too.

The warning was delivered by a British scientist, Professor Sir Robert Watson, chair of the UN’s Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), speaking in the French capital, Paris.

He told an IPBES meeting held to approve the summary of its new global assessment report on the state of life on Earth that the implications for human life were grave. The overwhelming evidence gathered in the assessment presented “an ominous picture. The health of ecosystems on which we and all other species depend is deteriorating more rapidly than ever.

“We are eroding the very foundations of our economies, livelihoods, food security, health and quality of life worldwide.”

“The essential, interconnected web of life on Earth is getting smaller and increasingly frayed, This loss is a direct result of human activity … ”

But Professor Watson, a previous chair of the UN’s Intergovernmental Panel on Climate Change (IPCC), does not preach despair. Despite the “truly unsustainable rate” of species loss that would affect human wellbeing for this generation and for its descendants, despite the accelerating pace of extinction, he believes there is still hope.

“We are in trouble if we don’t act, but there are a range of actions that can be taken to protect nature and meet human goals for health and development. It is not too late to make a difference, but only if we start now at every level from local to global.” Transformative change, system-wide and including goals and values, could allow humankind to restore nature and to use it sustainably, he said.

In an unusually forthright challenge to individuals, businesses and governments which continue to question or ignore the findings of science in pursuit of their own interests, Professor Watson, a globally-renowned environment scientist, acknowledged that that sort of change “can expect opposition from those with interests vested in the status quo”. Such opposition “can be overcome for the broader public good”, he added.

The assessment report’s findings make spine-chilling reading. It says the average abundance of native species in most major land-based habitats has fallen by at least 20%, mostly since 1900. More than 40% of amphibians and more than a third of all marine mammals are threatened. The picture is less clear for insects, but available evidence supports a tentative estimate of 10% being threatened.

Global impact

“The essential, interconnected web of life on Earth is getting smaller and increasingly frayed,” said Professor Josef Settele, one of the co-chairs of the global assessment, of the Helmholtz Centre for Environmental Research in Germany . “This loss is a direct result of human activity and constitutes a direct threat to human well-being in all regions of the world.”

The summary says there are five main causes of the crisis. In descending order they are: changes in land and sea use; direct exploitation of animals and plants; climate change; pollution; and invasive alien species.

It adds plenty of detail:

•Three-quarters of the land-based environment and about 66% of the marine environment have been significantly altered by human actions. On average these trends have been less severe or avoided in areas held or managed by indigenous peoples and local communities

•More than a third of the world’s land surface and nearly 75% of freshwater resources are now devoted to crop or livestock production

•Raw timber demand has risen by 45% and approximately 60 billion tons of renewable and non-renewable resources are now extracted globally every year – having nearly doubled since 1980

Land degradation has reduced the productivity of 23% of the global land surface, up to US$577bn in annual global crops are at risk from pollinator loss, and 100-300 million people are at increased risk of floods and hurricanes because of loss of coastal habitats and protection

•Since 1980 plastic pollution has increased tenfold

•Since 1992 urban areas have more than doubled

•In 2015, 33% of marine fish stocks were being harvested at unsustainable levels.

.Numbers unknown

Scientists point out that unlike the five earlier great waves of extinction to have occurred on the planet, this one is human-driven. IPBES has explained simply and clearly that humankind and its activities are responsible for what is happening, and that we shall have to pay the price.

IPBES has also succeeded in diagnosing the extent of the crisis overwhelming the natural world with a new degree of precision, despite the fact that nobody can say with any certainty how many species the Earth contains.

The Paris meeting approved the 40-page summary of the full IPBES report, which will be published later this year. At the end of 2020 two conferences, on the natural world and climate change, will provide global leaders with an opportunity to make specific plans for action.

Extinction Rebellion (XR), the group whose protests in April brought traffic in parts of London to a halt for a week and which is active in several other countries as well, is known for its vociferous demands for steps to tackle climate change.

It is careful to spell out its insistence that climate change and the fate of the natural world are twin threats, of equal gravity and urgency. − Climate News Network

For the sixth time since life on Earth began, scientists say, mass extinction is a threat. This time, though, is different. The cause is us.

LONDON, 7 May, 2019 − About one million of the world’s animal and plant species are now at risk of extinction − the largest number in human history ever to be facing the threat of oblivion, scientists say. Many species could be wiped out within decades. And their plight is caused by humans, and will inevitably affect us too.

The warning was delivered by a British scientist, Professor Sir Robert Watson, chair of the UN’s Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), speaking in the French capital, Paris.

He told an IPBES meeting held to approve the summary of its new global assessment report on the state of life on Earth that the implications for human life were grave. The overwhelming evidence gathered in the assessment presented “an ominous picture. The health of ecosystems on which we and all other species depend is deteriorating more rapidly than ever.

“We are eroding the very foundations of our economies, livelihoods, food security, health and quality of life worldwide.”

“The essential, interconnected web of life on Earth is getting smaller and increasingly frayed, This loss is a direct result of human activity … ”

But Professor Watson, a previous chair of the UN’s Intergovernmental Panel on Climate Change (IPCC), does not preach despair. Despite the “truly unsustainable rate” of species loss that would affect human wellbeing for this generation and for its descendants, despite the accelerating pace of extinction, he believes there is still hope.

“We are in trouble if we don’t act, but there are a range of actions that can be taken to protect nature and meet human goals for health and development. It is not too late to make a difference, but only if we start now at every level from local to global.” Transformative change, system-wide and including goals and values, could allow humankind to restore nature and to use it sustainably, he said.

In an unusually forthright challenge to individuals, businesses and governments which continue to question or ignore the findings of science in pursuit of their own interests, Professor Watson, a globally-renowned environment scientist, acknowledged that that sort of change “can expect opposition from those with interests vested in the status quo”. Such opposition “can be overcome for the broader public good”, he added.

The assessment report’s findings make spine-chilling reading. It says the average abundance of native species in most major land-based habitats has fallen by at least 20%, mostly since 1900. More than 40% of amphibians and more than a third of all marine mammals are threatened. The picture is less clear for insects, but available evidence supports a tentative estimate of 10% being threatened.

Global impact

“The essential, interconnected web of life on Earth is getting smaller and increasingly frayed,” said Professor Josef Settele, one of the co-chairs of the global assessment, of the Helmholtz Centre for Environmental Research in Germany . “This loss is a direct result of human activity and constitutes a direct threat to human well-being in all regions of the world.”

The summary says there are five main causes of the crisis. In descending order they are: changes in land and sea use; direct exploitation of animals and plants; climate change; pollution; and invasive alien species.

It adds plenty of detail:

•Three-quarters of the land-based environment and about 66% of the marine environment have been significantly altered by human actions. On average these trends have been less severe or avoided in areas held or managed by indigenous peoples and local communities

•More than a third of the world’s land surface and nearly 75% of freshwater resources are now devoted to crop or livestock production

•Raw timber demand has risen by 45% and approximately 60 billion tons of renewable and non-renewable resources are now extracted globally every year – having nearly doubled since 1980

Land degradation has reduced the productivity of 23% of the global land surface, up to US$577bn in annual global crops are at risk from pollinator loss, and 100-300 million people are at increased risk of floods and hurricanes because of loss of coastal habitats and protection

•Since 1980 plastic pollution has increased tenfold

•Since 1992 urban areas have more than doubled

•In 2015, 33% of marine fish stocks were being harvested at unsustainable levels.

.Numbers unknown

Scientists point out that unlike the five earlier great waves of extinction to have occurred on the planet, this one is human-driven. IPBES has explained simply and clearly that humankind and its activities are responsible for what is happening, and that we shall have to pay the price.

IPBES has also succeeded in diagnosing the extent of the crisis overwhelming the natural world with a new degree of precision, despite the fact that nobody can say with any certainty how many species the Earth contains.

The Paris meeting approved the 40-page summary of the full IPBES report, which will be published later this year. At the end of 2020 two conferences, on the natural world and climate change, will provide global leaders with an opportunity to make specific plans for action.

Extinction Rebellion (XR), the group whose protests in April brought traffic in parts of London to a halt for a week and which is active in several other countries as well, is known for its vociferous demands for steps to tackle climate change.

It is careful to spell out its insistence that climate change and the fate of the natural world are twin threats, of equal gravity and urgency. − Climate News Network

Human impact on climate is 100 years old

When did the human impact on climate begin? At least a century ago, with the arrival of the bi-plane, the chauffeur-driven car and the Jazz Age.

LONDON, 2 May, 2019 − Our influence on the Earth’s environment has lasted for a century: the human impact on droughts and moisture patterns began at least 100 years ago, researchers now say.

US scientists used new analytic techniques and almost a thousand years of tree-ring data to build up a picture of drought and rainfall worldwide for the last century. And they report in the journal Nature that they have identified the human fingerprint upon climate variation as far back as the first days of the motor car and the infant aircraft industry.

The pattern of change, in which regions prone to drought such as the western US became more arid, grew visible between 1900 and 1949. The researchers saw the same pattern of drying in those decades in Australia, Europe, the Mediterranean, western Russia and southeast Asia.

At the same time more rain and snow fell in western China, much of central Asia, the Indian subcontinent, Indonesia and central Canada.

Clear signal apparent

Kate Marvel of the Nasa Goddard Institute for Space Studies, who led the research, said: “It’s mind-boggling. There really is a clear signal of the effects of greenhouse gases on the hydroclimate.”

And Benjamin Cook of both the Nasa Institute and the Lamont-Doherty Earth Observatory at Columbia University, said: “We asked, does the real world look like what the models tell us to expect? The answer is yes.

“The big thing we learned is that climate change started affecting global patterns of drought in the early 20th century. We expect this pattern to keep emerging as climate change continues.”

For four decades it has been a given of climate change research that average planetary warming will intensify all the extremes of weather: in particular, drought and flood.

“All the models are projecting that you should see unprecedented drying soon, in a lot of places”

The problem has been that droughts and floods have always happened. But could scientists identify the signature of human change – the clearing of the forests, the intensification of agriculture, the growth of the cities and the ever-increasing use of fossil fuels to dump ever more carbon dioxide in the atmosphere – in any one flood or drought? Until this century, researchers were unwilling to name the guilty party.

No longer. In recent years researchers have done more than just blame overall warming on human activity, and in particular the increasing hazard of extremes of heat, drought and flood.

They have linked human behaviour with drought in California and with record temperatures in 2013 in Australia.

The Nasa-led research is not quite the first to claim to have detected very early evidence of climate change. A team led by Chinese scientists reported in April in the journal Nature Sustainability that tree ring evidence from the Tibetan plateau suggested that humans may have begun altering the pattern of seasonal temperatures – that is, the differences between winter and summer – as early as the 1870s, at least in the northern hemisphere.

Puzzle solved?

But the latest study from Dr Marvel and colleagues identifies such evidence on a wider scale, and may even have resolved the puzzle of the extremes that did not happen.

The research found three distinct periods of change. The first was marked by more drought in some places, more precipitation in others in the first half of the 20th century. But by the height of the Cold War, and the space race mid-century, it became harder to see a pattern, and climate events seemed more random, and climates cooler.

The researchers now think the huge volumes of aerosols from power stations, factory chimneys and vehicle exhausts between 1950 and 1975 altered weather patterns in different ways, affecting cloud formation, rainfall and temperature, to mask the effect of greenhouse gas increases.

These were the years of choking smog, grime and soot, sulphurous droplets, acid rain, corroding historic buildings and urban respiratory disease on an epidemic scale.

Stronger patternn expected

And then developed nations started introducing clean air legislation and other pollution controls. Round about 1981, tentative evidence of the impact of human-driven greenhouse gas emissions began to show again in the climate record, although not as boldly as in the first half of the century.

If the researchers have got it right, the pattern of increasing drought, matched elsewhere by increasing precipitation, will continue to become stronger.

“If we don’t see it coming in stronger in, say, the next 10 years, we might have to wonder whether we are right,” Dr Marvel said. “But all the models are projecting that you should see unprecedented drying soon, in a lot of places.”

And the researchers warn that the consequences for humankind, especially in North America and Eurasia, could be severe. − Climate News Network

When did the human impact on climate begin? At least a century ago, with the arrival of the bi-plane, the chauffeur-driven car and the Jazz Age.

LONDON, 2 May, 2019 − Our influence on the Earth’s environment has lasted for a century: the human impact on droughts and moisture patterns began at least 100 years ago, researchers now say.

US scientists used new analytic techniques and almost a thousand years of tree-ring data to build up a picture of drought and rainfall worldwide for the last century. And they report in the journal Nature that they have identified the human fingerprint upon climate variation as far back as the first days of the motor car and the infant aircraft industry.

The pattern of change, in which regions prone to drought such as the western US became more arid, grew visible between 1900 and 1949. The researchers saw the same pattern of drying in those decades in Australia, Europe, the Mediterranean, western Russia and southeast Asia.

At the same time more rain and snow fell in western China, much of central Asia, the Indian subcontinent, Indonesia and central Canada.

Clear signal apparent

Kate Marvel of the Nasa Goddard Institute for Space Studies, who led the research, said: “It’s mind-boggling. There really is a clear signal of the effects of greenhouse gases on the hydroclimate.”

And Benjamin Cook of both the Nasa Institute and the Lamont-Doherty Earth Observatory at Columbia University, said: “We asked, does the real world look like what the models tell us to expect? The answer is yes.

“The big thing we learned is that climate change started affecting global patterns of drought in the early 20th century. We expect this pattern to keep emerging as climate change continues.”

For four decades it has been a given of climate change research that average planetary warming will intensify all the extremes of weather: in particular, drought and flood.

“All the models are projecting that you should see unprecedented drying soon, in a lot of places”

The problem has been that droughts and floods have always happened. But could scientists identify the signature of human change – the clearing of the forests, the intensification of agriculture, the growth of the cities and the ever-increasing use of fossil fuels to dump ever more carbon dioxide in the atmosphere – in any one flood or drought? Until this century, researchers were unwilling to name the guilty party.

No longer. In recent years researchers have done more than just blame overall warming on human activity, and in particular the increasing hazard of extremes of heat, drought and flood.

They have linked human behaviour with drought in California and with record temperatures in 2013 in Australia.

The Nasa-led research is not quite the first to claim to have detected very early evidence of climate change. A team led by Chinese scientists reported in April in the journal Nature Sustainability that tree ring evidence from the Tibetan plateau suggested that humans may have begun altering the pattern of seasonal temperatures – that is, the differences between winter and summer – as early as the 1870s, at least in the northern hemisphere.

Puzzle solved?

But the latest study from Dr Marvel and colleagues identifies such evidence on a wider scale, and may even have resolved the puzzle of the extremes that did not happen.

The research found three distinct periods of change. The first was marked by more drought in some places, more precipitation in others in the first half of the 20th century. But by the height of the Cold War, and the space race mid-century, it became harder to see a pattern, and climate events seemed more random, and climates cooler.

The researchers now think the huge volumes of aerosols from power stations, factory chimneys and vehicle exhausts between 1950 and 1975 altered weather patterns in different ways, affecting cloud formation, rainfall and temperature, to mask the effect of greenhouse gas increases.

These were the years of choking smog, grime and soot, sulphurous droplets, acid rain, corroding historic buildings and urban respiratory disease on an epidemic scale.

Stronger patternn expected

And then developed nations started introducing clean air legislation and other pollution controls. Round about 1981, tentative evidence of the impact of human-driven greenhouse gas emissions began to show again in the climate record, although not as boldly as in the first half of the century.

If the researchers have got it right, the pattern of increasing drought, matched elsewhere by increasing precipitation, will continue to become stronger.

“If we don’t see it coming in stronger in, say, the next 10 years, we might have to wonder whether we are right,” Dr Marvel said. “But all the models are projecting that you should see unprecedented drying soon, in a lot of places.”

And the researchers warn that the consequences for humankind, especially in North America and Eurasia, could be severe. − Climate News Network

Climate science supports youth protests

The youth protests urging political action on climate change have won strong global backing from climatologists, as over 6,000 scientists express their support.

LONDON, 19 April, 2019 – The global youth protests demanding action on climate change are having a marked effect.

In their thousands, concerned climate scientists, backed by colleagues from other disciplines, are voicing support for the school students and other young people who are staying away from lessons to urge more resolute political action to protect the climate.

The campaign to support the protesters has been launched by an international group of 22 scientists spanning a range of disciplines; several of them are renowned climate specialists.

They include Michael Mann, professor of atmospheric science at Penn State University, US, Kevin Anderson, professor of energy and climate change at the University of Manchester, UK, and Stefan Rahmstorf.

Reasons to protest

Climate News Network asked Stefan Rahmstorf, professor of physics of the oceans at the University of Potsdam, Germany, what he would tell a hesitant potential protester in order to allay his doubts.

He replied: “Politicians are already starting to move in response to the school strikes around the world. Fridays for Future is perhaps our last chance to get meaningful climate policies that can still achieve the goals of the Paris Agreement. Time is running out fast.”

By mid-April the scientists who had signed the declaration numbered almost 6,300. The 22 original signatories  explained why they backed the protests in a letter to the journal Science headed Concerns of young protesters are justified.

Known as Scientists for Future International, they are linked to the website which co-ordinates the protests worldwide, Fridays for Future (the protests are held on Fridays).

Justified concerns

The letter starts with a ringing declaration: “The world’s youth have begun to persistently demonstrate for the protection of the climate and other foundations of human well-being … Their concerns are justified and supported by the best available science. The current measures for protecting the climate and biosphere are deeply inadequate.”

It includes a clear call to move from protest to action to tackle the multiple environmental threats now confronting the next generation: limiting global warming, halting the mass extinction of other species and safeguarding food supplies.

“This is what the young people want to achieve. They deserve our respect and full support.”

In March the estimated worldwide number of protesters was around 1.5 million.

“Politicians are already starting to move in response to the school strikes around the world. Fridays for Future is perhaps our last chance to get meaningful climate policies

In support of its declaration of backing for the protesters, Scientists for Future International says almost every country has signed and ratified the Paris Agreement of 2015, agreeing to keep global warming well below 2°C above pre-industrial levels, and aiming to limit the temperature increase to 1.5°C.

“The scientific community has clearly concluded that a global warming of 2°C instead of 1.5°C would substantially increase climate-related impacts and the risk of some becoming irreversible.

“It is critical to immediately begin a rapid reduction in CO2 and other greenhouse gas emissions. The degree of climate crisis that humanity will experience in the future will be determined by our cumulative emissions; rapid reduction now will limit the damage.

“For example, the Intergovernmental Panel on Climate Change (IPCC) has recently assessed that halving CO2 emissions by 2030 (relative to 2010 levels) and globally achieving net-zero CO2 emissions by 2050 (as well as strong reductions in other greenhouse gases) would allow a 50% chance of staying below 1.5°C of warming.”

Time is short

It says many solutions to the climate crisis already exist, and only bold action can avert the critical danger that threatens the protesters’ future. It adds: “There is no time to wait until they are in power.”

The statement ends: “The enormous grassroots mobilisation of the youth climate movement … shows that young people understand the situation. We approve and support their demand for rapid and forceful action. We see it as our social, ethical, and scholarly responsibility to state [this] in no uncertain terms.

“Only if humanity acts quickly and resolutely can we limit global warming, halt the ongoing mass extinction of animal and plant species, and preserve the natural basis for the food supply and well-being of present and future generations.

“This is what the young people want to achieve. They deserve our respect and full support.” –  Climate News Network

* * * * *

Anyone wanting to add their names to the Scientists for Future International declaration – and who meets its eligibility requirements – will find it here. It is published under a Creative Commons licence (CC BY-SA 4.0) and can be freely shared.

The youth protests urging political action on climate change have won strong global backing from climatologists, as over 6,000 scientists express their support.

LONDON, 19 April, 2019 – The global youth protests demanding action on climate change are having a marked effect.

In their thousands, concerned climate scientists, backed by colleagues from other disciplines, are voicing support for the school students and other young people who are staying away from lessons to urge more resolute political action to protect the climate.

The campaign to support the protesters has been launched by an international group of 22 scientists spanning a range of disciplines; several of them are renowned climate specialists.

They include Michael Mann, professor of atmospheric science at Penn State University, US, Kevin Anderson, professor of energy and climate change at the University of Manchester, UK, and Stefan Rahmstorf.

Reasons to protest

Climate News Network asked Stefan Rahmstorf, professor of physics of the oceans at the University of Potsdam, Germany, what he would tell a hesitant potential protester in order to allay his doubts.

He replied: “Politicians are already starting to move in response to the school strikes around the world. Fridays for Future is perhaps our last chance to get meaningful climate policies that can still achieve the goals of the Paris Agreement. Time is running out fast.”

By mid-April the scientists who had signed the declaration numbered almost 6,300. The 22 original signatories  explained why they backed the protests in a letter to the journal Science headed Concerns of young protesters are justified.

Known as Scientists for Future International, they are linked to the website which co-ordinates the protests worldwide, Fridays for Future (the protests are held on Fridays).

Justified concerns

The letter starts with a ringing declaration: “The world’s youth have begun to persistently demonstrate for the protection of the climate and other foundations of human well-being … Their concerns are justified and supported by the best available science. The current measures for protecting the climate and biosphere are deeply inadequate.”

It includes a clear call to move from protest to action to tackle the multiple environmental threats now confronting the next generation: limiting global warming, halting the mass extinction of other species and safeguarding food supplies.

“This is what the young people want to achieve. They deserve our respect and full support.”

In March the estimated worldwide number of protesters was around 1.5 million.

“Politicians are already starting to move in response to the school strikes around the world. Fridays for Future is perhaps our last chance to get meaningful climate policies

In support of its declaration of backing for the protesters, Scientists for Future International says almost every country has signed and ratified the Paris Agreement of 2015, agreeing to keep global warming well below 2°C above pre-industrial levels, and aiming to limit the temperature increase to 1.5°C.

“The scientific community has clearly concluded that a global warming of 2°C instead of 1.5°C would substantially increase climate-related impacts and the risk of some becoming irreversible.

“It is critical to immediately begin a rapid reduction in CO2 and other greenhouse gas emissions. The degree of climate crisis that humanity will experience in the future will be determined by our cumulative emissions; rapid reduction now will limit the damage.

“For example, the Intergovernmental Panel on Climate Change (IPCC) has recently assessed that halving CO2 emissions by 2030 (relative to 2010 levels) and globally achieving net-zero CO2 emissions by 2050 (as well as strong reductions in other greenhouse gases) would allow a 50% chance of staying below 1.5°C of warming.”

Time is short

It says many solutions to the climate crisis already exist, and only bold action can avert the critical danger that threatens the protesters’ future. It adds: “There is no time to wait until they are in power.”

The statement ends: “The enormous grassroots mobilisation of the youth climate movement … shows that young people understand the situation. We approve and support their demand for rapid and forceful action. We see it as our social, ethical, and scholarly responsibility to state [this] in no uncertain terms.

“Only if humanity acts quickly and resolutely can we limit global warming, halt the ongoing mass extinction of animal and plant species, and preserve the natural basis for the food supply and well-being of present and future generations.

“This is what the young people want to achieve. They deserve our respect and full support.” –  Climate News Network

* * * * *

Anyone wanting to add their names to the Scientists for Future International declaration – and who meets its eligibility requirements – will find it here. It is published under a Creative Commons licence (CC BY-SA 4.0) and can be freely shared.

Extreme heat is growing threat to harvests

A warmer world means more chance of extreme heat in more than one continent at the same time, and a rising threat to global food security.

LONDON, 17 April, 2019 − Ever-higher average global temperatures mean more intense extreme heat over ever-wider regions.

When the planet becomes on average 1.5°C warmer than it was for most of human history, then for two out of every three years, one-fourth of the northern hemisphere will experience the kind of blistering heat waves recorded in 2018.

And should planetary average temperatures creep up by 2°C – the maximum proposed by 195 nations at the global climate conference in Paris in 2015 – then the probability rises to 100%. That is, extreme heat over a large area of the hemisphere will be guaranteed every summer.

Heat extremes are all too often accompanied by devastating thunderstorms or extended drought and massive outbreaks of wildfire, with potentially disastrous consequences for harvests in the blighted regions.

“Ultimately, extreme events affecting large areas of the planet could threaten food supply elsewhere, even in Switzerland”

In 2018, people died of heatstroke, roads and even rails started to melt, forests went up in flames, and power generation systems sometimes failed, not just in one region but in a number in the temperate zones and the Arctic at the same time.

Between May and July, 22% of agricultural land and crowded cities of the northern half of the globe were hit simultaneously by extended periods of extreme heat. In all, 17 countries were affected, from Canada and the US across the Atlantic and Pacific to Russia, Japan and South Korea. In Europe, temperatures in the rivers Rhine and Elbe reached such heights that fish suffocated; there were wildfires in Sweden, Latvia and Greece and record temperatures in Germany.

“Without climate change that can be explained by human activity, we wouldn’t have such a large area being simultaneously affected by heat as we did in 2018,” said Martha Vogel, of the Swiss Federal Institute of Technology, known as ETH Zurich, who presented her findings at a press conference held by the European Geosciences Union in Vienna.

Serious impacts

The reasoning and methodology have yet to be published, but the authors say their paper is in review for the journal Earth’s Future. “If in future more and more key agricultural regions and densely populated areas are affected by simultaneous heatwaves, this would have severe consequences.”

Other research teams have already warned that global warming could bring a repeat of the simultaneous drought and heat outbreaks across the world that triggered calamitous famines in Asia and Africa between 1875 and 1878.

They have repeatedly warned of potentially catastrophic levels of heat that could arrive with increasing frequency to claim greater numbers of lives especially when accompanied by extreme levels of humidity.

The Swiss scientists focussed on data from agricultural regions and busy urban areas above latitude 30° for the years 1958 to 2018 to find occasions of heat extremes in more than one region and then used computer modelling to simulate probabilities as average planetary temperatures continued to grow.

Poor are hardest-hit

The choice of agricultural areas was purposeful: in such scenarios where more than one region suffers harvest failures, food prices begin to soar. In the 2010 heatwave, Russia ended all its wheat exports and prices in Pakistan rose by 16%, with harsh consequences for the poorest. Governments, agriculture ministries and international aid agencies need to be prepared.

“Such incidents cannot be resolved by individual countries acting on their own. Ultimately, extreme events affecting large areas of the planet could threaten food supply elsewhere, even in Switzerland,” said Sonia Seneviratne, an ETH climate scientist who has also shared in the study.

“We are already clearly feeling the effects just from the one degree that global average temperature has risen since the pre-industrial era.” − Climate News Network

A warmer world means more chance of extreme heat in more than one continent at the same time, and a rising threat to global food security.

LONDON, 17 April, 2019 − Ever-higher average global temperatures mean more intense extreme heat over ever-wider regions.

When the planet becomes on average 1.5°C warmer than it was for most of human history, then for two out of every three years, one-fourth of the northern hemisphere will experience the kind of blistering heat waves recorded in 2018.

And should planetary average temperatures creep up by 2°C – the maximum proposed by 195 nations at the global climate conference in Paris in 2015 – then the probability rises to 100%. That is, extreme heat over a large area of the hemisphere will be guaranteed every summer.

Heat extremes are all too often accompanied by devastating thunderstorms or extended drought and massive outbreaks of wildfire, with potentially disastrous consequences for harvests in the blighted regions.

“Ultimately, extreme events affecting large areas of the planet could threaten food supply elsewhere, even in Switzerland”

In 2018, people died of heatstroke, roads and even rails started to melt, forests went up in flames, and power generation systems sometimes failed, not just in one region but in a number in the temperate zones and the Arctic at the same time.

Between May and July, 22% of agricultural land and crowded cities of the northern half of the globe were hit simultaneously by extended periods of extreme heat. In all, 17 countries were affected, from Canada and the US across the Atlantic and Pacific to Russia, Japan and South Korea. In Europe, temperatures in the rivers Rhine and Elbe reached such heights that fish suffocated; there were wildfires in Sweden, Latvia and Greece and record temperatures in Germany.

“Without climate change that can be explained by human activity, we wouldn’t have such a large area being simultaneously affected by heat as we did in 2018,” said Martha Vogel, of the Swiss Federal Institute of Technology, known as ETH Zurich, who presented her findings at a press conference held by the European Geosciences Union in Vienna.

Serious impacts

The reasoning and methodology have yet to be published, but the authors say their paper is in review for the journal Earth’s Future. “If in future more and more key agricultural regions and densely populated areas are affected by simultaneous heatwaves, this would have severe consequences.”

Other research teams have already warned that global warming could bring a repeat of the simultaneous drought and heat outbreaks across the world that triggered calamitous famines in Asia and Africa between 1875 and 1878.

They have repeatedly warned of potentially catastrophic levels of heat that could arrive with increasing frequency to claim greater numbers of lives especially when accompanied by extreme levels of humidity.

The Swiss scientists focussed on data from agricultural regions and busy urban areas above latitude 30° for the years 1958 to 2018 to find occasions of heat extremes in more than one region and then used computer modelling to simulate probabilities as average planetary temperatures continued to grow.

Poor are hardest-hit

The choice of agricultural areas was purposeful: in such scenarios where more than one region suffers harvest failures, food prices begin to soar. In the 2010 heatwave, Russia ended all its wheat exports and prices in Pakistan rose by 16%, with harsh consequences for the poorest. Governments, agriculture ministries and international aid agencies need to be prepared.

“Such incidents cannot be resolved by individual countries acting on their own. Ultimately, extreme events affecting large areas of the planet could threaten food supply elsewhere, even in Switzerland,” said Sonia Seneviratne, an ETH climate scientist who has also shared in the study.

“We are already clearly feeling the effects just from the one degree that global average temperature has risen since the pre-industrial era.” − Climate News Network