Tag Archives: Temperature rise

World is halfway through its hottest decade

Things are warming up: already the world is halfway through its hottest decade on record, if predictions prove correct.

LONDON, 13 February, 2019 – Here is a climate forecast that climate scientists, meteorologists, politicians, voters and even climate sceptics can check: the next five years will be warm, and will probably help to complete the hottest decade ever.

They will on a global average be at least 1°C higher than the average temperature of the planet 200 years ago, before the accelerating combustion of fossil fuels.

That is because the planet is already midway through what may well prove to be its warmest 10 years since records began on a planetary scale in 1850. There is even a possibility that within the next five years, the global temperature rise could tip 1.5°C above the long-term average for human history.

This is the ambitious limit to global warming that the world set itself at an historic meeting in Paris in 2015, for the year 2100.

And the forecasters can make such predictions with some confidence because tomorrow’s temperature chart is already inscribed in the air we breathe: the pattern of warming over the last century is consistent with the steady rise in greenhouse gas levels in the atmosphere, and these are still increasing because fossil fuel use is still going up.

“Predictions now suggest around a 10% chance of at least one year between 2019 and 2023 temporarily exceeding 1.5°C”

Adam Scaife, who heads long-range prediction research at the UK Met Office, said: “2015 was the first year that global annual average surface temperatures reached 1.0°C above pre-industrial levels and the following three years have all remained close to this level.

“The global average temperature between now and 2023 is predicted to remain high, potentially making the decade from 2014 the warmest in more than 150 years of records.”

Climate is what people can reasonably bank on; weather is what they get. The forecast is significant because it is evidence of swelling confidence in the understanding of global warming and climate change science.

Climate researchers began warning at least 40 years ago of the potentially calamitous consequences of climate change: they were, at the time, unwilling to link any single weather event – flood, drought, windstorm or heat wave – to long-term global warming as a consequence of the steady increase of carbon dioxide in the atmosphere, released from power stations, factory chimneys and vehicle exhausts.

Possible catastrophe predicted

Not any more: in 2013, one group of geographers in Hawaii even predicted the possible onset of catastrophic climate change in some regions of the globe as early as 2020.

And the Met Office prediction is accompanied by a danger that – for a short while at least – the global increase could reach or exceed the level that 195 nations in Paris agreed would be potentially disastrous for human civilisation.

“A run of temperatures of 1.0°C or above would increase the risk of a temporary excursion above the threshold of 1.5°C above pre-industrial levels,” said Doug Smith, a researcher at the Met Office. “Predictions now suggest around a 10% chance of at least one year between 2019 and 2023 temporarily exceeding 1.5°C.”

Global temperatures in 2018 were around 0.91°C above the long-term average. This would make 2018 the fourth warmest year ever, although oceanographers recently warned that the oceans – and 70% of the planet is covered by ocean – reached their warmest ever in 2018.

Almost imperceptible

The three warmest years on record are 2015, 2016 and 2017. Climate scientists – and health chiefs – have consistently warned that the average global increase is at almost imperceptible pace, and is a trend rather than a year-on-year rise. This made it possible for some to argue about the interpretation of the data, and to even claim that global warming had paused.

But within this slow increase in average temperatures, there has been a pattern of increasing extremes of rainfall and temperature with the threat of increasingly frequent and potentially lethal heat waves to come.

And, researchers warned recently, the changes seem inexorable: by multiplying in number to more than 7bn in two centuries, by clearing forests and by burning fossil fuels, humans have managed to reverse a long-term climate trend and make the future uncomfortably hot.

A third UK researcher, Tim Osborn of the University of East Anglia’s Cllimatic Research Unit, spelled it out: “The warmth of 2018 is in line with the long-term warming trend driven by the world’s emissions of greenhouse gases.” – Climate News Network

Things are warming up: already the world is halfway through its hottest decade on record, if predictions prove correct.

LONDON, 13 February, 2019 – Here is a climate forecast that climate scientists, meteorologists, politicians, voters and even climate sceptics can check: the next five years will be warm, and will probably help to complete the hottest decade ever.

They will on a global average be at least 1°C higher than the average temperature of the planet 200 years ago, before the accelerating combustion of fossil fuels.

That is because the planet is already midway through what may well prove to be its warmest 10 years since records began on a planetary scale in 1850. There is even a possibility that within the next five years, the global temperature rise could tip 1.5°C above the long-term average for human history.

This is the ambitious limit to global warming that the world set itself at an historic meeting in Paris in 2015, for the year 2100.

And the forecasters can make such predictions with some confidence because tomorrow’s temperature chart is already inscribed in the air we breathe: the pattern of warming over the last century is consistent with the steady rise in greenhouse gas levels in the atmosphere, and these are still increasing because fossil fuel use is still going up.

“Predictions now suggest around a 10% chance of at least one year between 2019 and 2023 temporarily exceeding 1.5°C”

Adam Scaife, who heads long-range prediction research at the UK Met Office, said: “2015 was the first year that global annual average surface temperatures reached 1.0°C above pre-industrial levels and the following three years have all remained close to this level.

“The global average temperature between now and 2023 is predicted to remain high, potentially making the decade from 2014 the warmest in more than 150 years of records.”

Climate is what people can reasonably bank on; weather is what they get. The forecast is significant because it is evidence of swelling confidence in the understanding of global warming and climate change science.

Climate researchers began warning at least 40 years ago of the potentially calamitous consequences of climate change: they were, at the time, unwilling to link any single weather event – flood, drought, windstorm or heat wave – to long-term global warming as a consequence of the steady increase of carbon dioxide in the atmosphere, released from power stations, factory chimneys and vehicle exhausts.

Possible catastrophe predicted

Not any more: in 2013, one group of geographers in Hawaii even predicted the possible onset of catastrophic climate change in some regions of the globe as early as 2020.

And the Met Office prediction is accompanied by a danger that – for a short while at least – the global increase could reach or exceed the level that 195 nations in Paris agreed would be potentially disastrous for human civilisation.

“A run of temperatures of 1.0°C or above would increase the risk of a temporary excursion above the threshold of 1.5°C above pre-industrial levels,” said Doug Smith, a researcher at the Met Office. “Predictions now suggest around a 10% chance of at least one year between 2019 and 2023 temporarily exceeding 1.5°C.”

Global temperatures in 2018 were around 0.91°C above the long-term average. This would make 2018 the fourth warmest year ever, although oceanographers recently warned that the oceans – and 70% of the planet is covered by ocean – reached their warmest ever in 2018.

Almost imperceptible

The three warmest years on record are 2015, 2016 and 2017. Climate scientists – and health chiefs – have consistently warned that the average global increase is at almost imperceptible pace, and is a trend rather than a year-on-year rise. This made it possible for some to argue about the interpretation of the data, and to even claim that global warming had paused.

But within this slow increase in average temperatures, there has been a pattern of increasing extremes of rainfall and temperature with the threat of increasingly frequent and potentially lethal heat waves to come.

And, researchers warned recently, the changes seem inexorable: by multiplying in number to more than 7bn in two centuries, by clearing forests and by burning fossil fuels, humans have managed to reverse a long-term climate trend and make the future uncomfortably hot.

A third UK researcher, Tim Osborn of the University of East Anglia’s Cllimatic Research Unit, spelled it out: “The warmth of 2018 is in line with the long-term warming trend driven by the world’s emissions of greenhouse gases.” – Climate News Network

Human carbon emissions to rise in 2019

Here comes another dismal science forecast, with human carbon emissions due to rise this year. Forests may be unable to keep pace as global warming increases.

LONDON, 31 January, 2019 − Stand by for a year in which global warming can only get worse as human carbon emissions climb still further. British meteorologists warn that although 2018 broke all records for greenhouse gas emissions, 2019 will see even more carbon dioxide take up long-term residence in the planetary atmosphere.

And it will happen for two reasons, both of them nominally at least under human control. The overall release of carbon dioxide from power stations, factory chimneys, cement quarries, car exhausts and so on will continue to rise with fossil fuel combustion, even though there has been greater investment than ever in renewable resources such as wind and solar energy.

And those natural “sinks” that absorb extra carbon from the atmosphere and sequester it as living timber in the forests, or bones and shells in the oceans, are expected to under-perform.

This is largely because of natural cyclic variation in the tropical climate, but also partly because humans continue to degrade grasslands and fell or burn the forests that naturally absorb carbon dioxide from the atmosphere and return oxygen for the animal world to breathe.

Hawaii’s unique record

Climate scientists know what is going to happen because they can see the future already written in a unique 60-year-old cycle of data recorded high on a mountaintop in Hawaii, in the Pacific, far from any heavy industry or city pollution that might distort the local chemistry of the atmosphere.

“Since 1958, monitoring at the Mauna Loa observatory in Hawaii has registered around a 30% increase in the concentration of carbon dioxide in the atmosphere,” said Richard Betts, of the UK Met Office’s Hadley Centre.

“This is caused by emissions from fossil fuels, deforestation and cement production, and the increase would have been even larger if it were not for natural carbon sinks which soak up some of the excess CO2.

This year we expect these carbon sinks to be relatively weak, so the impact of record high human-caused emissions will be larger than last year.”

“Deforestation in the Brazilian Amazon increased to around 8,000 square kilometres in 2018, equivalent to losing a football pitch of forest every 80 seconds”

At the heart of the diagnosis is the increasing understanding of the role of the world’s great oceans in managing planetary weather patterns.

A year ago the tropical Pacific was relatively cool, rainfall increased and land-based ecosystems flourished, soaking up atmospheric carbon. In a relatively warm cycle, many regions become warmer and drier, which in turn limits plant growth.

Carbon dioxide ratios in the global atmosphere for most of human history, until the Industrial Revolution and the arrival of the steam age and the internal combustion engine, oscillated at around 280 parts per million (ppm). In the last decade, the ratio reached 400 ppm, and in 2018 peaked at 414.7 ppm in May, before beginning to fall in the northern hemisphere growing season, to rise again in September.

El Niño distortion

Overall, the average for 2018 was 411 ppm, with an uncertainty factor of 0.6 ppm. In 2019, the average is likely to be 2.75 ppm higher still. This would be one of the largest annual rises on record.

The rises in 2015-2016 and in 1997-1998 were higher, but these years’ readings were distorted by the arrival of a dramatic but natural Pacific warming called El Niño, always associated with a sudden and often damaging shift in regional climate patterns far away.

Climate scientists have continued to hope for a global response to such predictions: these are the people who are professionally most aware of the big picture of global change.

Julienne Stroeve of University College London called the news “discouraging, for sure. Last year the extra CO2 was equivalent to melting about 110,000 square kilometres of Arctic Sea ice, or roughly three times the area of Switzerland. Sea ice loss is directly tied to increases in atmospheric CO2.”

Damage to forests

And Jos Barlow, of Lancaster University’s Environment Centre, warned that forest clearance in the tropics continued as a hazard.

Deforestation in the Brazilian Amazon increased to around 8,000 square kilometres in 2018, which is equivalent to losing a football pitch of forest every 80 seconds. This alone would result in CO2 emissions that exceed those of the UK over the same time period.”

Professor Betts called the Mauna Loa record of atmospheric carbon dioxide a “thing of beauty” and a stark reminder of human interference with the planetary climate.

“Looking at the monthly figures, it’s as if you can see the planet ‘breathing’ as the levels of carbon dioxide fall and rise with the seasonal cycle of plant growth and decay in the northern hemisphere. But each year’s CO2 is higher than the last, and this will keep happening until humans stop adding CO2 to the atmosphere.” − Climate News Network

Here comes another dismal science forecast, with human carbon emissions due to rise this year. Forests may be unable to keep pace as global warming increases.

LONDON, 31 January, 2019 − Stand by for a year in which global warming can only get worse as human carbon emissions climb still further. British meteorologists warn that although 2018 broke all records for greenhouse gas emissions, 2019 will see even more carbon dioxide take up long-term residence in the planetary atmosphere.

And it will happen for two reasons, both of them nominally at least under human control. The overall release of carbon dioxide from power stations, factory chimneys, cement quarries, car exhausts and so on will continue to rise with fossil fuel combustion, even though there has been greater investment than ever in renewable resources such as wind and solar energy.

And those natural “sinks” that absorb extra carbon from the atmosphere and sequester it as living timber in the forests, or bones and shells in the oceans, are expected to under-perform.

This is largely because of natural cyclic variation in the tropical climate, but also partly because humans continue to degrade grasslands and fell or burn the forests that naturally absorb carbon dioxide from the atmosphere and return oxygen for the animal world to breathe.

Hawaii’s unique record

Climate scientists know what is going to happen because they can see the future already written in a unique 60-year-old cycle of data recorded high on a mountaintop in Hawaii, in the Pacific, far from any heavy industry or city pollution that might distort the local chemistry of the atmosphere.

“Since 1958, monitoring at the Mauna Loa observatory in Hawaii has registered around a 30% increase in the concentration of carbon dioxide in the atmosphere,” said Richard Betts, of the UK Met Office’s Hadley Centre.

“This is caused by emissions from fossil fuels, deforestation and cement production, and the increase would have been even larger if it were not for natural carbon sinks which soak up some of the excess CO2.

This year we expect these carbon sinks to be relatively weak, so the impact of record high human-caused emissions will be larger than last year.”

“Deforestation in the Brazilian Amazon increased to around 8,000 square kilometres in 2018, equivalent to losing a football pitch of forest every 80 seconds”

At the heart of the diagnosis is the increasing understanding of the role of the world’s great oceans in managing planetary weather patterns.

A year ago the tropical Pacific was relatively cool, rainfall increased and land-based ecosystems flourished, soaking up atmospheric carbon. In a relatively warm cycle, many regions become warmer and drier, which in turn limits plant growth.

Carbon dioxide ratios in the global atmosphere for most of human history, until the Industrial Revolution and the arrival of the steam age and the internal combustion engine, oscillated at around 280 parts per million (ppm). In the last decade, the ratio reached 400 ppm, and in 2018 peaked at 414.7 ppm in May, before beginning to fall in the northern hemisphere growing season, to rise again in September.

El Niño distortion

Overall, the average for 2018 was 411 ppm, with an uncertainty factor of 0.6 ppm. In 2019, the average is likely to be 2.75 ppm higher still. This would be one of the largest annual rises on record.

The rises in 2015-2016 and in 1997-1998 were higher, but these years’ readings were distorted by the arrival of a dramatic but natural Pacific warming called El Niño, always associated with a sudden and often damaging shift in regional climate patterns far away.

Climate scientists have continued to hope for a global response to such predictions: these are the people who are professionally most aware of the big picture of global change.

Julienne Stroeve of University College London called the news “discouraging, for sure. Last year the extra CO2 was equivalent to melting about 110,000 square kilometres of Arctic Sea ice, or roughly three times the area of Switzerland. Sea ice loss is directly tied to increases in atmospheric CO2.”

Damage to forests

And Jos Barlow, of Lancaster University’s Environment Centre, warned that forest clearance in the tropics continued as a hazard.

Deforestation in the Brazilian Amazon increased to around 8,000 square kilometres in 2018, which is equivalent to losing a football pitch of forest every 80 seconds. This alone would result in CO2 emissions that exceed those of the UK over the same time period.”

Professor Betts called the Mauna Loa record of atmospheric carbon dioxide a “thing of beauty” and a stark reminder of human interference with the planetary climate.

“Looking at the monthly figures, it’s as if you can see the planet ‘breathing’ as the levels of carbon dioxide fall and rise with the seasonal cycle of plant growth and decay in the northern hemisphere. But each year’s CO2 is higher than the last, and this will keep happening until humans stop adding CO2 to the atmosphere.” − Climate News Network

Permafrost thaws as global warming sets in

Global warming is at work far below the surface, at depths seemingly insulated from the greenhouse effect. This is bad news for the permafrost.

LONDON, 29 January, 2019 – Even in the coldest places – 10 metres below the surface of the polar wastes – global warming has begun to work. A new study of the frozen soils in both hemispheres shows that between 2007 and 2016, they warmed by an average of 0.3°C.

This remained true within the Arctic and Antarctic zones, in the highest mountain regions of Europe and Asia, and even in the Siberian tundra, where the temperatures at depth rose by almost a whole degree.

New research into the permafrost, defined as territory where soil has been frozen for at least two consecutive years, suggests that much of it may not be permanently frozen for much longer.

Climate scientists have repeatedly warned that along with the tilth, clays and sediments the icy structures store vast amounts of carbon in the form of yet-to-be-decomposed plant material.

So the thawing permafrost could surrender even more warming agents in the form of greenhouse gases, and accelerate global warming even further.

“The permafrost isn’t simply warming on a local and regional scale, but worldwide and at virtually the same pace as climate warming”

Researchers based in Potsdam, Germany report in the journal Nature Communications that they and colleagues in the Global Terrestrial Network for Permafrost monitored and measured soil temperatures in boreholes at 154 locations; more than 120 of them over a 10-year cycle. In a dozen locations the temperatures actually fell, and at 40 locations there was virtually no change.

The most dramatic warming was in the Arctic, where soils that were more than 90% permafrost increased temperatures by 0.3°C, and the Siberian north, where temperatures rose by 0.9°C or more. Air temperatures over those regions had risen by an average of 0.6°C in the same decade. In those Arctic regions with less than 90% permafrost, the frozen ground had warmed by 0.2°C.

“In these regions there is more and more snowfall, which insulates the permafrost in two ways, following the igloo principle,” said Boris Biskaborn of the Alfred Wegener Institute, at the Helmholtz Centre for Polar and Marine Research, who led the study.

“In winter snow protects the soil from extreme cold, which on average produces a warming effect. In spring it reflects the sunlight, and prevents the soils from being exposed to too much warmth, at least until the snow has completely melted away.”

Widespread impact

The scientists also report that soil temperature rises were recorded in the Alps of Europe, the mountain ranges of Scandinavia, and in the Himalayas.

Other scientists have already this year identified potential disaster for many settlements in the Arctic regions: the once-hard-frozen topsoils are in danger of thawing, and since these support industrial buildings, oil and gas pipelines, road surfaces, and even whole towns, the danger of severe damage to infrastructure is growing.

And, the researchers warn, even if the world sticks to its promise, made by 195 nations in Paris in 2015, and contains global warming to no more than 2°C over pre-industrial levels by 2100, there is still a likelihood that the permafrost will disappear over a large area, to surrender more greenhouse gases, and trigger more warming.

“All this data tells us that the permafrost isn’t simply warming on a local and regional scale, but worldwide and at virtually the same pace as climate warming, which is producing a substantial warming of the air and increased snow thickness, especially in the Arctic,” said Guido Grosse, who heads permafrost research in Potsdam. “These two factors produce a warming of the once permanently frozen ground.” – Climate News Network

Global warming is at work far below the surface, at depths seemingly insulated from the greenhouse effect. This is bad news for the permafrost.

LONDON, 29 January, 2019 – Even in the coldest places – 10 metres below the surface of the polar wastes – global warming has begun to work. A new study of the frozen soils in both hemispheres shows that between 2007 and 2016, they warmed by an average of 0.3°C.

This remained true within the Arctic and Antarctic zones, in the highest mountain regions of Europe and Asia, and even in the Siberian tundra, where the temperatures at depth rose by almost a whole degree.

New research into the permafrost, defined as territory where soil has been frozen for at least two consecutive years, suggests that much of it may not be permanently frozen for much longer.

Climate scientists have repeatedly warned that along with the tilth, clays and sediments the icy structures store vast amounts of carbon in the form of yet-to-be-decomposed plant material.

So the thawing permafrost could surrender even more warming agents in the form of greenhouse gases, and accelerate global warming even further.

“The permafrost isn’t simply warming on a local and regional scale, but worldwide and at virtually the same pace as climate warming”

Researchers based in Potsdam, Germany report in the journal Nature Communications that they and colleagues in the Global Terrestrial Network for Permafrost monitored and measured soil temperatures in boreholes at 154 locations; more than 120 of them over a 10-year cycle. In a dozen locations the temperatures actually fell, and at 40 locations there was virtually no change.

The most dramatic warming was in the Arctic, where soils that were more than 90% permafrost increased temperatures by 0.3°C, and the Siberian north, where temperatures rose by 0.9°C or more. Air temperatures over those regions had risen by an average of 0.6°C in the same decade. In those Arctic regions with less than 90% permafrost, the frozen ground had warmed by 0.2°C.

“In these regions there is more and more snowfall, which insulates the permafrost in two ways, following the igloo principle,” said Boris Biskaborn of the Alfred Wegener Institute, at the Helmholtz Centre for Polar and Marine Research, who led the study.

“In winter snow protects the soil from extreme cold, which on average produces a warming effect. In spring it reflects the sunlight, and prevents the soils from being exposed to too much warmth, at least until the snow has completely melted away.”

Widespread impact

The scientists also report that soil temperature rises were recorded in the Alps of Europe, the mountain ranges of Scandinavia, and in the Himalayas.

Other scientists have already this year identified potential disaster for many settlements in the Arctic regions: the once-hard-frozen topsoils are in danger of thawing, and since these support industrial buildings, oil and gas pipelines, road surfaces, and even whole towns, the danger of severe damage to infrastructure is growing.

And, the researchers warn, even if the world sticks to its promise, made by 195 nations in Paris in 2015, and contains global warming to no more than 2°C over pre-industrial levels by 2100, there is still a likelihood that the permafrost will disappear over a large area, to surrender more greenhouse gases, and trigger more warming.

“All this data tells us that the permafrost isn’t simply warming on a local and regional scale, but worldwide and at virtually the same pace as climate warming, which is producing a substantial warming of the air and increased snow thickness, especially in the Arctic,” said Guido Grosse, who heads permafrost research in Potsdam. “These two factors produce a warming of the once permanently frozen ground.” – Climate News Network

Extinction toll may be far worse than thought

Yet again, researchers have confirmed that climate change threatens the natural world with a soaring extinction toll. The danger may be much higher than anyone imagined.

LONDON, 11 December, 2018 − Two scientists want the world to think again about the extinction toll, the rate at which species could vanish as the planet warms. They warn that the worst fears so far may have been based on underestimates. Tomorrow’s rates of extinction could be 10 times worse.

That is because the loss of one or two key species could turn into a cascade that could spell the end for whole ecosystems. “Primary extinctions driven by environmental change could be just the tip of an enormous extinction iceberg,” they warn.

In their study, long before the complete loss of one species, other species locked into the same ecosystem started to perish. There is no need to worry about the rare but real hazard of an asteroid impact, or a burst of gamma rays from a nearby exploding star. The message from the simulators is that global average warming of between 5° and 6°C above the level for most of history since the end of the last Ice Age would be enough to wipe out most life on the hypothetical Earths.

“This makes it difficult to be optimistic about the future of species diversity in the ongoing trajectory of global change, let alone in the case of additional external, extraplanetary catastrophes.”

Giovanni Strona of the European Commission’s joint research centre in Ispra, Italy and Corey Bradshaw of Finders University in Adelaide, Australia write in the journal Scientific Reports that they turned to computer simulation to resolve an enduring ecological question: quite what is it that drives biodiversity loss?

“Whenever a species leaves our planet, we lose much more than a name on a list”

The growth in human numbers, and the exploitation of the planet’s surface for economic growth, has destroyed habitats and disrupted ecosystems on a scale without parallel: global warming and climate change will make things worse.

Researchers have confirmed, repeatedly, that ecosystems are under threat; that climate change could be even more damaging than anyone suspected; that half of 976 species in one study were already being extinguished in local ecosystems, even if they survived elsewhere as the thermometer rose.

But most such studies were based on sample examinations of specific patches of woodland, grassland, marsh or lake, or surveys of published literature, and they measured change in a planet that has – since the beginning of the Industrial Revolution – warmed by about 1°C as a consequence of profligate combustion of fossil fuels and the clearance of the great forests. The latest study involved testing life on a planet to destruction.

The two scientists constructed 2,000 “virtual Earths” and populated them with interacting species: that is with a food web composed of competing predators and prey, multiple consumers and consumed. Then they subjected these notional biospheres to extreme environmental change, ranging from runaway global warming driven by ever-greater greenhouse gas emissions to the sudden, intense cooling of a “nuclear winter” in which sunlight is blocked by the dust of global thermonuclear war.

And the experiments, they say, demonstrated, once again, the co-dependency of living things in a stable environment. They set up two scenarios. In one of them a species was subjected to temperature change to the point of extinction. In the other, the researchers triggered a series of co-extinction cascades. They then matched the two outcomes.

More than species

And they found that failure to take into account the complex, entangled interdependencies of living things led to an underestimate, by 10 times, of the magnitude of mass extinction by climate change alone. The message is: don’t just save the giant panda, save the forest.

“Conservationists and decision makers need to move fast beyond a species-specific approach, and look with increasing attention at interaction networks as a fundamental conservation target,” Dr Strona said. “Whenever a species leaves our planet, we lose much more than a name on a list.”

Other such simulations have delivered catastrophic conclusions: one examination of runaway global warming left the Earth uninhabitable, while another found that in the most dreadful outcomes, at least one life form, the tardigrade, might survive.

Any computer model of life on Earth must have its weaknesses, if only because the unknown and unnamed list of creatures is at least 10 times greater than those already catalogued in the world’s botanical gardens, zoos and natural history museums. That is, biologists still don’t know nearly enough about the diversity of life on Earth. There are, the researchers concede, “obvious limitations in our ambitions model.”

But, said Dr Strona: “Our results are consistent with real-world patterns for which we have empirical evidence. This makes us confident that the many assumptions we had to take in order to build a functional model are sound. On the other hand, it would be misleading to just focus on raw numbers.” − Climate News Network

Yet again, researchers have confirmed that climate change threatens the natural world with a soaring extinction toll. The danger may be much higher than anyone imagined.

LONDON, 11 December, 2018 − Two scientists want the world to think again about the extinction toll, the rate at which species could vanish as the planet warms. They warn that the worst fears so far may have been based on underestimates. Tomorrow’s rates of extinction could be 10 times worse.

That is because the loss of one or two key species could turn into a cascade that could spell the end for whole ecosystems. “Primary extinctions driven by environmental change could be just the tip of an enormous extinction iceberg,” they warn.

In their study, long before the complete loss of one species, other species locked into the same ecosystem started to perish. There is no need to worry about the rare but real hazard of an asteroid impact, or a burst of gamma rays from a nearby exploding star. The message from the simulators is that global average warming of between 5° and 6°C above the level for most of history since the end of the last Ice Age would be enough to wipe out most life on the hypothetical Earths.

“This makes it difficult to be optimistic about the future of species diversity in the ongoing trajectory of global change, let alone in the case of additional external, extraplanetary catastrophes.”

Giovanni Strona of the European Commission’s joint research centre in Ispra, Italy and Corey Bradshaw of Finders University in Adelaide, Australia write in the journal Scientific Reports that they turned to computer simulation to resolve an enduring ecological question: quite what is it that drives biodiversity loss?

“Whenever a species leaves our planet, we lose much more than a name on a list”

The growth in human numbers, and the exploitation of the planet’s surface for economic growth, has destroyed habitats and disrupted ecosystems on a scale without parallel: global warming and climate change will make things worse.

Researchers have confirmed, repeatedly, that ecosystems are under threat; that climate change could be even more damaging than anyone suspected; that half of 976 species in one study were already being extinguished in local ecosystems, even if they survived elsewhere as the thermometer rose.

But most such studies were based on sample examinations of specific patches of woodland, grassland, marsh or lake, or surveys of published literature, and they measured change in a planet that has – since the beginning of the Industrial Revolution – warmed by about 1°C as a consequence of profligate combustion of fossil fuels and the clearance of the great forests. The latest study involved testing life on a planet to destruction.

The two scientists constructed 2,000 “virtual Earths” and populated them with interacting species: that is with a food web composed of competing predators and prey, multiple consumers and consumed. Then they subjected these notional biospheres to extreme environmental change, ranging from runaway global warming driven by ever-greater greenhouse gas emissions to the sudden, intense cooling of a “nuclear winter” in which sunlight is blocked by the dust of global thermonuclear war.

And the experiments, they say, demonstrated, once again, the co-dependency of living things in a stable environment. They set up two scenarios. In one of them a species was subjected to temperature change to the point of extinction. In the other, the researchers triggered a series of co-extinction cascades. They then matched the two outcomes.

More than species

And they found that failure to take into account the complex, entangled interdependencies of living things led to an underestimate, by 10 times, of the magnitude of mass extinction by climate change alone. The message is: don’t just save the giant panda, save the forest.

“Conservationists and decision makers need to move fast beyond a species-specific approach, and look with increasing attention at interaction networks as a fundamental conservation target,” Dr Strona said. “Whenever a species leaves our planet, we lose much more than a name on a list.”

Other such simulations have delivered catastrophic conclusions: one examination of runaway global warming left the Earth uninhabitable, while another found that in the most dreadful outcomes, at least one life form, the tardigrade, might survive.

Any computer model of life on Earth must have its weaknesses, if only because the unknown and unnamed list of creatures is at least 10 times greater than those already catalogued in the world’s botanical gardens, zoos and natural history museums. That is, biologists still don’t know nearly enough about the diversity of life on Earth. There are, the researchers concede, “obvious limitations in our ambitions model.”

But, said Dr Strona: “Our results are consistent with real-world patterns for which we have empirical evidence. This makes us confident that the many assumptions we had to take in order to build a functional model are sound. On the other hand, it would be misleading to just focus on raw numbers.” − Climate News Network

2018 will show record carbon emissions

Record carbon emissions are set to mark 2018. And although investment in renewable energy is rising, the world is still warming dangerously fast.

LONDON, 6 December, 2018 – For the second year running, the world will have a doubtful achievement to claim by 31 December: record carbon emissions.

Even before the close of 2018, scientists behind the biggest accounting effort on the planet, the Global Carbon Budget, warn that emissions from coal, oil and gas will have dumped a record 37 billion tonnes of carbon dioxide equivalent (a way of  comparing the emissions from various greenhouse gases based on their global warming potential) into the atmosphere by the end of this month.

This is 2.7% more than last year, which also showed an increase. Human destruction of the world’s forests will add another four billion tonnes in the same 12 months.

The news comes as 190 nations negotiate in Katowice in Poland to work out how to meet the targets they set in 2015 in Paris,  to contain global warming to no more than 2°C by 2100, and if possible no more than 1.5°C.

Little time left

But in a commentary in Nature a second set of scientists warns that time is running out. At the present rate of fossil fuel use, the world is set to breach the 1.5°C target by 2030, rather than the 2040 everybody had assumed.

That is because rising emissions, declining air pollution and natural climate cycles working together will make climate change more fast and furious than expected.

There are hopeful signs: renewable energy investment has begun to accelerate, and some nations have started to reduce fossil fuel emissions.

But the confirmation of yet another record year for fossil fuel combustion – after three consecutive years, 2014-16, in which fossil fuel use seemed to have peaked and might start to fall – suggests that even those nations most concerned about climate change are not doing enough.

“This cannot continue. It must not. To give us a chance of meeting the Paris climate goals, emissions need to fall, and fast”

The biggest emitters are China, the US, India, Russia, Japan, Germany, Saudi Arabia, South Korea and Canada, but taken as a collective, the European Union elbows India out of third place.

If the UK, a self-proclaimed climate progressive country, could celebrate the exploitation of a new North Sea oil field while at the same time exploring for shale gas and expanding its biggest airport, it should be no surprise that global emissions were rising, said Kevin Anderson, professor of energy and climate change at the Tyndall Centre at the University of Manchester, UK.

“If the climate-aware EU is planning new pan-Europe pipelines to lock in high carbon gas for decades to come, is it any surprise global emissions are rising? If ever-green Sweden, currently without any major gas infrastructure, is enthusiastically building a new gas terminal in Gothenburg – is it any surprise emissions are rising?”

Aimed at negotiators

Publication of the Global Carbon Project review for 2018 is timed to focus minds in Katowice, and as a reminder of how much has yet to be done to contain climate change.

“To limit global warming to the Paris Agreement goal of 1.5°C, CO2 emissions would need to decline by 50% by 2030 and reach zero around 2050,” said Corinne Le Quéré, who directs theTyndall Centre for climate change at the University of East Anglia, UK.

“We are a long way from this, and much more needs to be done because if countries stick to commitments they have already made, we are on track to see 3°C of global warming.

“This year we have seen how climate change can already amplify the impact of heatwaves worldwide. The California wildfires are just a snapshot of the growing impacts we face if we don’t drive emissions down rapidly.”

Renewable energy grows

Paradoxically, the data in the report published in one version in Environmental Research Letters and in more detail in the journal Earth System Science Data also point to an acceleration towards renewable sources of energy: the political shorthand for this process is “decarbonisation.”

Coal consumption in Canada and the US had dropped 40% since 2005. Christiana Figueres, who in 2015 as a UN climate chief presided over the wheeling and dealing that resulted in the Paris Agreement, argues in another commentary in Nature that there are signs of promise.

Thousands of businesses in 120 countries had signed up to the Paris goals, which could bring $26 trillion in economic benefits, including 65 million new jobs in what she called the “booming” low carbon economy. “We have already achieved things that seemed unimaginable just a decade ago,” she said.

Robust accounting

“Exponential progress in key solutions is happening and on track to displace fossil fuels. Renewable energy costs have dropped by 80% in a decade, and today, over half of all new energy generation capacity is renewable.

“Before 2015 many people thought the Paris Agreement was impossible, yet thousands of people and institutions made the shift from impossible to unstoppable.”

But, warned David Reay, professor of carbon management at the University of Edinburgh, UK, the accounting within the balance sheet for the carbon budget 2018 was robust.

“Its message is more brutal than ever: we are in the red and still heading deeper. This cannot continue. It must not. To give us a chance of meeting the Paris climate goals, emissions need to fall, and fast. We knew this in 2015, we know it now. And yet they still rise.” – Climate News Network

Record carbon emissions are set to mark 2018. And although investment in renewable energy is rising, the world is still warming dangerously fast.

LONDON, 6 December, 2018 – For the second year running, the world will have a doubtful achievement to claim by 31 December: record carbon emissions.

Even before the close of 2018, scientists behind the biggest accounting effort on the planet, the Global Carbon Budget, warn that emissions from coal, oil and gas will have dumped a record 37 billion tonnes of carbon dioxide equivalent (a way of  comparing the emissions from various greenhouse gases based on their global warming potential) into the atmosphere by the end of this month.

This is 2.7% more than last year, which also showed an increase. Human destruction of the world’s forests will add another four billion tonnes in the same 12 months.

The news comes as 190 nations negotiate in Katowice in Poland to work out how to meet the targets they set in 2015 in Paris,  to contain global warming to no more than 2°C by 2100, and if possible no more than 1.5°C.

Little time left

But in a commentary in Nature a second set of scientists warns that time is running out. At the present rate of fossil fuel use, the world is set to breach the 1.5°C target by 2030, rather than the 2040 everybody had assumed.

That is because rising emissions, declining air pollution and natural climate cycles working together will make climate change more fast and furious than expected.

There are hopeful signs: renewable energy investment has begun to accelerate, and some nations have started to reduce fossil fuel emissions.

But the confirmation of yet another record year for fossil fuel combustion – after three consecutive years, 2014-16, in which fossil fuel use seemed to have peaked and might start to fall – suggests that even those nations most concerned about climate change are not doing enough.

“This cannot continue. It must not. To give us a chance of meeting the Paris climate goals, emissions need to fall, and fast”

The biggest emitters are China, the US, India, Russia, Japan, Germany, Saudi Arabia, South Korea and Canada, but taken as a collective, the European Union elbows India out of third place.

If the UK, a self-proclaimed climate progressive country, could celebrate the exploitation of a new North Sea oil field while at the same time exploring for shale gas and expanding its biggest airport, it should be no surprise that global emissions were rising, said Kevin Anderson, professor of energy and climate change at the Tyndall Centre at the University of Manchester, UK.

“If the climate-aware EU is planning new pan-Europe pipelines to lock in high carbon gas for decades to come, is it any surprise global emissions are rising? If ever-green Sweden, currently without any major gas infrastructure, is enthusiastically building a new gas terminal in Gothenburg – is it any surprise emissions are rising?”

Aimed at negotiators

Publication of the Global Carbon Project review for 2018 is timed to focus minds in Katowice, and as a reminder of how much has yet to be done to contain climate change.

“To limit global warming to the Paris Agreement goal of 1.5°C, CO2 emissions would need to decline by 50% by 2030 and reach zero around 2050,” said Corinne Le Quéré, who directs theTyndall Centre for climate change at the University of East Anglia, UK.

“We are a long way from this, and much more needs to be done because if countries stick to commitments they have already made, we are on track to see 3°C of global warming.

“This year we have seen how climate change can already amplify the impact of heatwaves worldwide. The California wildfires are just a snapshot of the growing impacts we face if we don’t drive emissions down rapidly.”

Renewable energy grows

Paradoxically, the data in the report published in one version in Environmental Research Letters and in more detail in the journal Earth System Science Data also point to an acceleration towards renewable sources of energy: the political shorthand for this process is “decarbonisation.”

Coal consumption in Canada and the US had dropped 40% since 2005. Christiana Figueres, who in 2015 as a UN climate chief presided over the wheeling and dealing that resulted in the Paris Agreement, argues in another commentary in Nature that there are signs of promise.

Thousands of businesses in 120 countries had signed up to the Paris goals, which could bring $26 trillion in economic benefits, including 65 million new jobs in what she called the “booming” low carbon economy. “We have already achieved things that seemed unimaginable just a decade ago,” she said.

Robust accounting

“Exponential progress in key solutions is happening and on track to displace fossil fuels. Renewable energy costs have dropped by 80% in a decade, and today, over half of all new energy generation capacity is renewable.

“Before 2015 many people thought the Paris Agreement was impossible, yet thousands of people and institutions made the shift from impossible to unstoppable.”

But, warned David Reay, professor of carbon management at the University of Edinburgh, UK, the accounting within the balance sheet for the carbon budget 2018 was robust.

“Its message is more brutal than ever: we are in the red and still heading deeper. This cannot continue. It must not. To give us a chance of meeting the Paris climate goals, emissions need to fall, and fast. We knew this in 2015, we know it now. And yet they still rise.” – Climate News Network

Farmers face double trouble as world warms

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

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

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

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

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

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

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

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

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

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

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

Lengthening odds

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

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

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

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

Extremes increase

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Lengthening odds

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

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

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

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

Extremes increase

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

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

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

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

Climate impacts will seldom strike singly

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

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

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

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

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

Medical prospects

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

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

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

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

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

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

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

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

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

List of impacts

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

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

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

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

Present danger

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

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

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

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

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

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

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

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

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

Medical prospects

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

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

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

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

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

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

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

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

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

List of impacts

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

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

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

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

Present danger

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

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

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

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

Worse storms in prospect as warmth rises

Once again, US government scientists warn that hurricane and flood hazard is amplified by a warming world. But worse storms are caused by big cities too.

LONDON, 19 November, 2018 – Worse storms are on the way, as many Americans know all too well. Hurricane Katrina was the costliest natural disaster ever to hit the US: it blew ashore over New Orleans in August 2005 to claim at least 1,833 lives and wreak economic damage worth, in today’s prices, $160bn.

And however bad it was, climate change made it worse. Because of global warming up to that point, up to 9% more rain fell over the city, some of it to sweep away the river defences and precipitate disastrous flooding.

A second study, also in Nature, warns: big cities make bad storms even worse. Urbanisation – all those roads, pavements, rooftops and so on – multiplies the risk of flooding on average 21-fold. The growth of Houston in Texas left a city at the mercy of Hurricane Harvey in 2017: the scale of flooding was without precedent.

The research is based on computer modelling of the impact of overall planetary warming – around 1°C in the past century – on local sea and coastal conditions.

Rising economic harm

Warmer atmospheres hold more water. With each 1°C rise, the capacity to absorb moisture increases by 7% , so in a warmer world storms will be wetter. With higher temperatures, storms are likely to be more ferocious. Researchers have repeatedly warned that because of these simple principles, as global temperatures rise, the US faces ever bigger economic losses each succeeding hurricane season.

Houston wasn’t prepared for what seemed like a once-in-a-thousand-years storm, but extreme rainstorms will become even more extreme and in Texas more Harvey-scale storms are on the way.

Water that falls on forest or wetland or coastal savannah is at least partly absorbed. Hard rain that hits tarmacadam and concrete could swiftly become a flash flood. So the latest study is a confirmation of much previous research.

“Efforts to build flood mitigation strategies must use an improved understanding of the multiple processes in place”

And although President Trump has condemned climate change science as a hoax devised by the Chinese, and announced a withdrawal from the Paris Agreement signed by 195 nations to limit global warming to if possible less than 2°C by 2100, the confirmation of greater climate change danger once again comes from a US government research base, the Lawrence Berkeley National Laboratory.

Christina Patricola, of the laboratory’s climate division, reports in Nature that she and a colleague chose 15 tropical cyclones that have occurred in the last decade in the Atlantic, the Pacific and the Indian Oceans, and then built computer simulations of those storms while changing factors such as air and ocean temperatures, humidity, and the greenhouse gas concentrations that dictate overall planetary temperatures.

The two scientists looked at the effects of climate change so far, and the shape of storms to come. They found that warming hitherto has made rainfall between 5% and 10% more intense, but may not have so far made much difference to overall hurricane windspeeds.

Strengthening winds

But if the climate continues to warm – and it could warm by 3°C or more this century, as ever greater combustion of fossil fuels puts ever more carbon dioxide into the atmosphere – peak wind speeds could increase by up to 25 knots or very nearly 50 kilometres per hour.

The scientists also found that future rainfall in such storms could increase by between 15% and 35%. And the same computer models that predict windier, wetter storms tomorrow accurately predicted the pattern of the storms that had already happened. “The fact that almost all of the 15 tropical cyclones responded in a similar way gives confidence to the results,” Dr Patricola said.

In a companion study, scientists from US universities looked at the other component of the Hurricane Harvey disaster in 2017: the changes in the city of Houston itself.

Between 25 and 30 August, Harvey dumped 1.3 metres of rain on the metropolis. Between 2000 and 2011, Houston had the largest urban growth and the fifth largest population growth in the entire US. That is, it became a bigger target, with a greater area of paving and sealed surfaces to channel the flowing water.

Slower and wetter

The changing contour of the city helped increase atmospheric drag, slowing the passage of the hurricane and delaying it for long enough to drop even more rain. And then the surface of asphalt and concrete made conditions worse.

So, the researchers concluded, the new building made the risk of catastrophic flooding somewhere between hardly at all and up to 90 times more likely, depending on which part of the city they were looking at. Altogether, the risk of more flooding on the scale of Harvey had increased 21-fold.

The message is that coastal cities must plan for the worst and keep planning. Hurricane winds and rainfall are going to intensify in the future. Cities will keep on growing as human numbers increase.

“Planning must take into account the compounded nature of these risks,” they conclude, “and efforts to build flood mitigation strategies must use an improved understanding of the multiple processes in place.” – Climate News Network

Once again, US government scientists warn that hurricane and flood hazard is amplified by a warming world. But worse storms are caused by big cities too.

LONDON, 19 November, 2018 – Worse storms are on the way, as many Americans know all too well. Hurricane Katrina was the costliest natural disaster ever to hit the US: it blew ashore over New Orleans in August 2005 to claim at least 1,833 lives and wreak economic damage worth, in today’s prices, $160bn.

And however bad it was, climate change made it worse. Because of global warming up to that point, up to 9% more rain fell over the city, some of it to sweep away the river defences and precipitate disastrous flooding.

A second study, also in Nature, warns: big cities make bad storms even worse. Urbanisation – all those roads, pavements, rooftops and so on – multiplies the risk of flooding on average 21-fold. The growth of Houston in Texas left a city at the mercy of Hurricane Harvey in 2017: the scale of flooding was without precedent.

The research is based on computer modelling of the impact of overall planetary warming – around 1°C in the past century – on local sea and coastal conditions.

Rising economic harm

Warmer atmospheres hold more water. With each 1°C rise, the capacity to absorb moisture increases by 7% , so in a warmer world storms will be wetter. With higher temperatures, storms are likely to be more ferocious. Researchers have repeatedly warned that because of these simple principles, as global temperatures rise, the US faces ever bigger economic losses each succeeding hurricane season.

Houston wasn’t prepared for what seemed like a once-in-a-thousand-years storm, but extreme rainstorms will become even more extreme and in Texas more Harvey-scale storms are on the way.

Water that falls on forest or wetland or coastal savannah is at least partly absorbed. Hard rain that hits tarmacadam and concrete could swiftly become a flash flood. So the latest study is a confirmation of much previous research.

“Efforts to build flood mitigation strategies must use an improved understanding of the multiple processes in place”

And although President Trump has condemned climate change science as a hoax devised by the Chinese, and announced a withdrawal from the Paris Agreement signed by 195 nations to limit global warming to if possible less than 2°C by 2100, the confirmation of greater climate change danger once again comes from a US government research base, the Lawrence Berkeley National Laboratory.

Christina Patricola, of the laboratory’s climate division, reports in Nature that she and a colleague chose 15 tropical cyclones that have occurred in the last decade in the Atlantic, the Pacific and the Indian Oceans, and then built computer simulations of those storms while changing factors such as air and ocean temperatures, humidity, and the greenhouse gas concentrations that dictate overall planetary temperatures.

The two scientists looked at the effects of climate change so far, and the shape of storms to come. They found that warming hitherto has made rainfall between 5% and 10% more intense, but may not have so far made much difference to overall hurricane windspeeds.

Strengthening winds

But if the climate continues to warm – and it could warm by 3°C or more this century, as ever greater combustion of fossil fuels puts ever more carbon dioxide into the atmosphere – peak wind speeds could increase by up to 25 knots or very nearly 50 kilometres per hour.

The scientists also found that future rainfall in such storms could increase by between 15% and 35%. And the same computer models that predict windier, wetter storms tomorrow accurately predicted the pattern of the storms that had already happened. “The fact that almost all of the 15 tropical cyclones responded in a similar way gives confidence to the results,” Dr Patricola said.

In a companion study, scientists from US universities looked at the other component of the Hurricane Harvey disaster in 2017: the changes in the city of Houston itself.

Between 25 and 30 August, Harvey dumped 1.3 metres of rain on the metropolis. Between 2000 and 2011, Houston had the largest urban growth and the fifth largest population growth in the entire US. That is, it became a bigger target, with a greater area of paving and sealed surfaces to channel the flowing water.

Slower and wetter

The changing contour of the city helped increase atmospheric drag, slowing the passage of the hurricane and delaying it for long enough to drop even more rain. And then the surface of asphalt and concrete made conditions worse.

So, the researchers concluded, the new building made the risk of catastrophic flooding somewhere between hardly at all and up to 90 times more likely, depending on which part of the city they were looking at. Altogether, the risk of more flooding on the scale of Harvey had increased 21-fold.

The message is that coastal cities must plan for the worst and keep planning. Hurricane winds and rainfall are going to intensify in the future. Cities will keep on growing as human numbers increase.

“Planning must take into account the compounded nature of these risks,” they conclude, “and efforts to build flood mitigation strategies must use an improved understanding of the multiple processes in place.” – Climate News Network

Mosquito evolution may alter as world warms

In the long term, some creatures will adapt to climate change and evolve. Mosquito evolution could bring new species – and new diseases.

LONDON, 15 November, 2018 – The hot breath of climate change could blow in new health hazards – if the past is a reliable guide. A shift in mosquito evolution could be triggered by ever greater levels of carbon dioxide in the atmosphere, fossil evidence matched with climate simulations suggests.

And in a new climate, and with new opportunities, there could follow new diseases, according to British researchers.

Mosquitoes already carry infections such as malaria, yellow fever, Zika virus, West Nile virus and dengue fever: diseases that kill millions each year. And mosquitoes are more than usually sensitive to CO2, which they exploit to detect potential sources of blood from the mammals on which they prey.

Researchers have repeatedly worried about what warming temperatures and changing climate could do for the mosquito-borne return of malaria to those cooler climates normally considered safe, and about the potential spread of tsetse fly as its normal habitat becomes too hot.

But any new emergent diseases from the mosquito remain academic: the scientists foresee evolutionary opportunities, likely to emerge over very long timespans.

“It’s only the female mosquitoes that take a blood meal, and they use the CO2 that mammals and other vertebrates exhale as a very general cue to locate their hosts”

Researchers report in the journal Communications Biology that they looked carefully at what they could establish about mosquito evolution, composed a “supertree” of the disease-bearing insect and its relatives, and mapped it against what they knew of past climate change.

There are mosquito fossils – though not very many – but these served as a kind of check on the evidence from the mathematical models of evolution that emerged.

As carbon dioxide levels rise, with ever greater combustion of fossil fuels to drive global warming, it could paradoxically be more difficult for mosquitoes to prey on their usual hosts. Environmental change provides opportunities for new evolutionary niches – and perhaps mosquitoes could find new hosts, and new infectious diseases could evolve?

“It’s only the female mosquitoes that take a blood meal, and they use the CO2 that mammals and other vertebrates exhale as a very general cue to locate their hosts.

Other clues

“One line of thinking is that as ambient levels of atmospheric CO2 rose, mosquitoes may have found it increasingly difficult to distinguish between the CO2 from their hosts and those background levels,” said Matthew Wills, of the University of Bath, one of the authors.

“Vision, body heat and other smells might then have become more important in locating their blood meals, but many of these cues tend to be more specific to particular hosts. As a general rule, we know that a strong host specificity can be an important driver of speciation in parasites, and the same may be true in mosquitoes.”

And Katie Davis, of the University of York, said: “We found that the increase in the diversity of mammals led directly to a rise in the number of mosquito species, and also that there is a relationship between CO2 levels and the number of mammal species, but there are still missing pieces of this puzzle, so we can still only speculate at this stage.”

But, she said, the research showed that mosquitoes could adapt to climate change and evolve. “With increased speciation, however, comes the added risk of disease increase and the return of certain diseases that had eradicated them or never experienced them before.” – Climate News Network

In the long term, some creatures will adapt to climate change and evolve. Mosquito evolution could bring new species – and new diseases.

LONDON, 15 November, 2018 – The hot breath of climate change could blow in new health hazards – if the past is a reliable guide. A shift in mosquito evolution could be triggered by ever greater levels of carbon dioxide in the atmosphere, fossil evidence matched with climate simulations suggests.

And in a new climate, and with new opportunities, there could follow new diseases, according to British researchers.

Mosquitoes already carry infections such as malaria, yellow fever, Zika virus, West Nile virus and dengue fever: diseases that kill millions each year. And mosquitoes are more than usually sensitive to CO2, which they exploit to detect potential sources of blood from the mammals on which they prey.

Researchers have repeatedly worried about what warming temperatures and changing climate could do for the mosquito-borne return of malaria to those cooler climates normally considered safe, and about the potential spread of tsetse fly as its normal habitat becomes too hot.

But any new emergent diseases from the mosquito remain academic: the scientists foresee evolutionary opportunities, likely to emerge over very long timespans.

“It’s only the female mosquitoes that take a blood meal, and they use the CO2 that mammals and other vertebrates exhale as a very general cue to locate their hosts”

Researchers report in the journal Communications Biology that they looked carefully at what they could establish about mosquito evolution, composed a “supertree” of the disease-bearing insect and its relatives, and mapped it against what they knew of past climate change.

There are mosquito fossils – though not very many – but these served as a kind of check on the evidence from the mathematical models of evolution that emerged.

As carbon dioxide levels rise, with ever greater combustion of fossil fuels to drive global warming, it could paradoxically be more difficult for mosquitoes to prey on their usual hosts. Environmental change provides opportunities for new evolutionary niches – and perhaps mosquitoes could find new hosts, and new infectious diseases could evolve?

“It’s only the female mosquitoes that take a blood meal, and they use the CO2 that mammals and other vertebrates exhale as a very general cue to locate their hosts.

Other clues

“One line of thinking is that as ambient levels of atmospheric CO2 rose, mosquitoes may have found it increasingly difficult to distinguish between the CO2 from their hosts and those background levels,” said Matthew Wills, of the University of Bath, one of the authors.

“Vision, body heat and other smells might then have become more important in locating their blood meals, but many of these cues tend to be more specific to particular hosts. As a general rule, we know that a strong host specificity can be an important driver of speciation in parasites, and the same may be true in mosquitoes.”

And Katie Davis, of the University of York, said: “We found that the increase in the diversity of mammals led directly to a rise in the number of mosquito species, and also that there is a relationship between CO2 levels and the number of mammal species, but there are still missing pieces of this puzzle, so we can still only speculate at this stage.”

But, she said, the research showed that mosquitoes could adapt to climate change and evolve. “With increased speciation, however, comes the added risk of disease increase and the return of certain diseases that had eradicated them or never experienced them before.” – Climate News Network

Arctic shorebirds face rising predation risk

Rapid warning means rapid change in the north. That’s bad news for the hardy Arctic shorebirds and delicate plants that once found safety there.

LONDON, 13 November, 2018 – Vulnerable baby birds are no longer safe in their nests. New research shows that nest predation – the theft of the eggs of migrant Arctic shorebirds such as plovers and sandpipers in the high latitudes of the northern hemisphere – has risen threefold in the last 70 years.

A second study suggests that the very thing that encourages Arctic plant growth – the rapid warming of the north polar regions – also means a loss of vital snow cover for the delicate plants in the high mountains that depend on snow for winter insulation. This is bad news for the snow buttercup, mountain sorrel and mossplant.

British, Czech, Russian and |Hungarian researchers report in the journal Science that they compared rates of nest robbery over two timespans, from 1944 to 1999 and from 2000 to 2015, around the world.

Altogether the study covered 38,191 nests in 237 populations of 111 species in 149 locations. Nest predation in the tropics was always higher – perhaps because there are more predators – and tropical bird species tend to counter offspring loss by living longer to generate more.

But, the researchers found, nest predation in temperate Europe, Asia and North America had doubled. And in the Arctic, nestling loss by shorebirds had risen threefold.

“The future changes in northern species populations may be abrupt, giving rise to ecological surprises that are hard to predict”

In fact, certain species have always flown far north to breed because until the Arctic began to warm rapidly, as a consequence of ever higher levels of the greenhouse gas carbon dioxide in the atmosphere, the Arctic provided a relatively safe space for ground-nesting birds.

The reason for ever greater nest losses? This has yet to be established. But the guess is that as change comes to the plants and animal life of the Arctic, either predator species have changed, or the loss of familiar prey has forced a change of diet on hunters.

Because snow cover in the high Arctic has changed the lemming population has crashed, and the carnivores that hunted lemmings may now have turned to birds’ nests.

“These findings are alarming. The Earth is a fragile planet with complex ecosystems, thus changes in predator-prey relationships can lead to cascading effects through the food web with detrimental consequences for many organisms thousands of kilometres away,” said Tamás Székely, a biologist at the University of Bath, UK, with research posts at Hungarian and Chinese universities.

Final blow

“Migration of shorebirds from the Arctic to the tropics is now one of the largest movements of biomass in the world. But with increased nest predation, the babies are no longer making the journeys with their parents. This could be the last nail in the coffin for critically-endangered species such as the spoon-billed sandpiper.”

And Vojtěch Kubelka, of Charles University in Prague, who led the research, said the Arctic was no longer a safe harbour for breeding birds. “On the contrary, the Arctic now represents an extensive ecological trap.”

Rapid warming of the north polar regions also means a more rapid invasion of plants from further south and a change in plant response.

Finnish scientists report in the journal Nature Climate Change that changes in snow cover on the high ground may be an even greater danger to Arctic biodiversity than rising temperatures.

Snow cover crucial

They looked at satellite data and computer-based models of probable change as humans burn ever more fossil fuels to drive global warming and climate change, and applied the results to 273 flowering plants, mosses and lichens at 1200 locations in the mountains of northern Scandinavia.

Snow that now lingers until late spring provides vital protection for fragile growths and prevents hardier southern species from colonising the same habitat. In brief, it limits the competition.

The great unknown remains snowfall: while climate scientists can be sure of likely future temperatures at any latitude, it is much harder to predict changes in precipitation. But if the snow cover is reduced, then local extinction rates could accelerate. Plants that once maintained a precarious hold in extreme conditions could vanish with the snows.

“Our findings show that the future changes in northern species populations may be abrupt, giving rise to ecological surprises that are hard to predict, such as fast eradications of populations in some places and the invasion of flexible species into new places”, said Risto Heikkinen from the Finnish Environment Institute. – Climate News Network

Rapid warning means rapid change in the north. That’s bad news for the hardy Arctic shorebirds and delicate plants that once found safety there.

LONDON, 13 November, 2018 – Vulnerable baby birds are no longer safe in their nests. New research shows that nest predation – the theft of the eggs of migrant Arctic shorebirds such as plovers and sandpipers in the high latitudes of the northern hemisphere – has risen threefold in the last 70 years.

A second study suggests that the very thing that encourages Arctic plant growth – the rapid warming of the north polar regions – also means a loss of vital snow cover for the delicate plants in the high mountains that depend on snow for winter insulation. This is bad news for the snow buttercup, mountain sorrel and mossplant.

British, Czech, Russian and |Hungarian researchers report in the journal Science that they compared rates of nest robbery over two timespans, from 1944 to 1999 and from 2000 to 2015, around the world.

Altogether the study covered 38,191 nests in 237 populations of 111 species in 149 locations. Nest predation in the tropics was always higher – perhaps because there are more predators – and tropical bird species tend to counter offspring loss by living longer to generate more.

But, the researchers found, nest predation in temperate Europe, Asia and North America had doubled. And in the Arctic, nestling loss by shorebirds had risen threefold.

“The future changes in northern species populations may be abrupt, giving rise to ecological surprises that are hard to predict”

In fact, certain species have always flown far north to breed because until the Arctic began to warm rapidly, as a consequence of ever higher levels of the greenhouse gas carbon dioxide in the atmosphere, the Arctic provided a relatively safe space for ground-nesting birds.

The reason for ever greater nest losses? This has yet to be established. But the guess is that as change comes to the plants and animal life of the Arctic, either predator species have changed, or the loss of familiar prey has forced a change of diet on hunters.

Because snow cover in the high Arctic has changed the lemming population has crashed, and the carnivores that hunted lemmings may now have turned to birds’ nests.

“These findings are alarming. The Earth is a fragile planet with complex ecosystems, thus changes in predator-prey relationships can lead to cascading effects through the food web with detrimental consequences for many organisms thousands of kilometres away,” said Tamás Székely, a biologist at the University of Bath, UK, with research posts at Hungarian and Chinese universities.

Final blow

“Migration of shorebirds from the Arctic to the tropics is now one of the largest movements of biomass in the world. But with increased nest predation, the babies are no longer making the journeys with their parents. This could be the last nail in the coffin for critically-endangered species such as the spoon-billed sandpiper.”

And Vojtěch Kubelka, of Charles University in Prague, who led the research, said the Arctic was no longer a safe harbour for breeding birds. “On the contrary, the Arctic now represents an extensive ecological trap.”

Rapid warming of the north polar regions also means a more rapid invasion of plants from further south and a change in plant response.

Finnish scientists report in the journal Nature Climate Change that changes in snow cover on the high ground may be an even greater danger to Arctic biodiversity than rising temperatures.

Snow cover crucial

They looked at satellite data and computer-based models of probable change as humans burn ever more fossil fuels to drive global warming and climate change, and applied the results to 273 flowering plants, mosses and lichens at 1200 locations in the mountains of northern Scandinavia.

Snow that now lingers until late spring provides vital protection for fragile growths and prevents hardier southern species from colonising the same habitat. In brief, it limits the competition.

The great unknown remains snowfall: while climate scientists can be sure of likely future temperatures at any latitude, it is much harder to predict changes in precipitation. But if the snow cover is reduced, then local extinction rates could accelerate. Plants that once maintained a precarious hold in extreme conditions could vanish with the snows.

“Our findings show that the future changes in northern species populations may be abrupt, giving rise to ecological surprises that are hard to predict, such as fast eradications of populations in some places and the invasion of flexible species into new places”, said Risto Heikkinen from the Finnish Environment Institute. – Climate News Network