Author: Tim Radford

About Tim Radford

Tim Radford, a founding editor of Climate News Network, worked for The Guardian for 32 years, for most of that time as science editor. He has been covering climate change since 1988.

Humans are set to hijack the fossil record

Humans have made an indelible mark on the planet: they may also have erased most of life’s other stories, distorting the fossil record, the narrative of creation.

LONDON, 2 January, 2020 – US scientists have made a prediction that some yet-to-evolve intelligent species a hundred million years into the future can test. One day the fossil record will be more than usually rich in the complete skeletons of a small number of creatures: pigs, sheep, cattle and humans, many of the last arranged seemingly in ranks.

The assemblage from what many scientists now call the Anthropocene – the geological era dominated by Homo sapiens – will be entirely unlike the pattern of preserved relics from all the other geological eras in the last 500 million years.

“Fossil mammals occur in caves, ancient lake beds and river channels, and are usually only teeth and isolated bones,” said Roy Plotnick, a palaeontologist at the University of Illinois in Chicago. “Animals that die on farms or in mass death due to disease often end up as complete corpses in trenches and landfills, far from water.”

Also available for study will be a vast array of undisturbed examples of one species that already far outnumbers all other large wild mammals. “In the far future, the fossil record of today will have a huge number of complete hominid skeletons, all lined up in rows.”

The thesis, outlined in the journal The Anthropocene, is a simple one. The evidence of past life preserved in the rocks is the only key to the story of life on Earth, and it has unfolded until now entirely by caprice.

“The future mammal record will be mostly cows, sheep, goats, pigs, dogs, cats and people themselves”

Animals that died in the Triassic, Jurassic or the Cretaceous were incompletely preserved. Upon death, they were liable to be dismantled by scavengers, swept away by floods, incinerated by fires, buried by lava or demolished entirely by microbes. Preservation of any kind was entirely a matter of geological caprice and bone structure: soft-bodied animals – and most living things have always been boneless – have almost no chance of preservation.

The North American passenger pigeon astonished the first European settlers. It existed by the billion-fold: one flock could be a mile wide and 200 miles long.

The last survivor perished in 1914 and, says Steve Jones in 1999, in his much-recommended examination of evolutionary insight, Almost Like a Whale, without a written record, no-one would now know it had ever existed: no fossil has ever been found.

The argument by Professor Plotnick and a colleague is a simple one. If preservation in fossilised form is a lottery, humankind has now taken over the management and rigged the odds.

Humans evolved from primate ancestors, but no primate species ever flourished in such numbers. Global population has soared almost eightfold in the last two centuries, and with humans the population of domesticated animals has multiplied dramatically: one species now threatens to eliminate many of the other inhabitants of the planet.

Preservation more probable

The mass of humanity, according to one calculation, long ago began to outweigh the gross mass of all other wild mammals on the planet, by at least 10-fold. And in such numbers, humans and their chosen species should stand a much better chance of preservation far into the future.

Homo sapiens has already fashioned cities, industries and constructions that gross up to trillions of tonnes of cement and metal, and in a few decades laid down a stratum of seemingly indestructible polymer material in the form of plastic cups, bottles, nets, cables and containers.

Erosion, earthquakes and time alone may wipe away many of the scars left by most construction work, but some will survive as evidence that at least one intelligent civilisation made it through evolution’s obstacle race before possibly ensuring its own collapse.

The chances of long-term preservation of the bones of the blue whale, the African lion, the mountain gorilla, the emperor penguin or even the jungle fowl, ancestor of the broiler chicken, will remain vanishingly small. But the factory farms and orderly cemeteries of today will dominate the evidence.

“The chance of a wild animal becoming part of the fossil record has become very small,” said Professor Plotnick. “Instead the future mammal record will be mostly cows, sheep, goats, pigs, dogs, cats and people themselves.” – Climate News Network

Humans have made an indelible mark on the planet: they may also have erased most of life’s other stories, distorting the fossil record, the narrative of creation.

LONDON, 2 January, 2020 – US scientists have made a prediction that some yet-to-evolve intelligent species a hundred million years into the future can test. One day the fossil record will be more than usually rich in the complete skeletons of a small number of creatures: pigs, sheep, cattle and humans, many of the last arranged seemingly in ranks.

The assemblage from what many scientists now call the Anthropocene – the geological era dominated by Homo sapiens – will be entirely unlike the pattern of preserved relics from all the other geological eras in the last 500 million years.

“Fossil mammals occur in caves, ancient lake beds and river channels, and are usually only teeth and isolated bones,” said Roy Plotnick, a palaeontologist at the University of Illinois in Chicago. “Animals that die on farms or in mass death due to disease often end up as complete corpses in trenches and landfills, far from water.”

Also available for study will be a vast array of undisturbed examples of one species that already far outnumbers all other large wild mammals. “In the far future, the fossil record of today will have a huge number of complete hominid skeletons, all lined up in rows.”

The thesis, outlined in the journal The Anthropocene, is a simple one. The evidence of past life preserved in the rocks is the only key to the story of life on Earth, and it has unfolded until now entirely by caprice.

“The future mammal record will be mostly cows, sheep, goats, pigs, dogs, cats and people themselves”

Animals that died in the Triassic, Jurassic or the Cretaceous were incompletely preserved. Upon death, they were liable to be dismantled by scavengers, swept away by floods, incinerated by fires, buried by lava or demolished entirely by microbes. Preservation of any kind was entirely a matter of geological caprice and bone structure: soft-bodied animals – and most living things have always been boneless – have almost no chance of preservation.

The North American passenger pigeon astonished the first European settlers. It existed by the billion-fold: one flock could be a mile wide and 200 miles long.

The last survivor perished in 1914 and, says Steve Jones in 1999, in his much-recommended examination of evolutionary insight, Almost Like a Whale, without a written record, no-one would now know it had ever existed: no fossil has ever been found.

The argument by Professor Plotnick and a colleague is a simple one. If preservation in fossilised form is a lottery, humankind has now taken over the management and rigged the odds.

Humans evolved from primate ancestors, but no primate species ever flourished in such numbers. Global population has soared almost eightfold in the last two centuries, and with humans the population of domesticated animals has multiplied dramatically: one species now threatens to eliminate many of the other inhabitants of the planet.

Preservation more probable

The mass of humanity, according to one calculation, long ago began to outweigh the gross mass of all other wild mammals on the planet, by at least 10-fold. And in such numbers, humans and their chosen species should stand a much better chance of preservation far into the future.

Homo sapiens has already fashioned cities, industries and constructions that gross up to trillions of tonnes of cement and metal, and in a few decades laid down a stratum of seemingly indestructible polymer material in the form of plastic cups, bottles, nets, cables and containers.

Erosion, earthquakes and time alone may wipe away many of the scars left by most construction work, but some will survive as evidence that at least one intelligent civilisation made it through evolution’s obstacle race before possibly ensuring its own collapse.

The chances of long-term preservation of the bones of the blue whale, the African lion, the mountain gorilla, the emperor penguin or even the jungle fowl, ancestor of the broiler chicken, will remain vanishingly small. But the factory farms and orderly cemeteries of today will dominate the evidence.

“The chance of a wild animal becoming part of the fossil record has become very small,” said Professor Plotnick. “Instead the future mammal record will be mostly cows, sheep, goats, pigs, dogs, cats and people themselves.” – Climate News Network

Little time left to arrest Greenland’s melting

Humans may still have time to stop Greenland’s melting, preventing Arctic ice sheet collapse and devastating sea level rise. But the time left may be short.

LONDON, 30 December, 2019 – It’s still possible, but it’s far from certain: stopping Greenland’s melting can be done, but it must be done soon.

Norwegian and US scientists have taken a close look at the ice age history of Greenland and come to a grim conclusion. All it takes to set the island’s ice cap melting away is a mean sea surface temperature higher than seven degrees Celsius. And the present mean sea surface temperature is already 7.7°C.

Greenland is the northern hemisphere’s single richest store of frozen water: the island’s bedrock holds enough to raise global sea levels by seven metres and drown or wash away the world’s coastal communities, including the great cities of New York and Miami, Shanghai and Kolkata, Amsterdam and London.

And the pattern of geological evidence – outlined in the Proceedings of the National Academy of Sciences – combined with climate models suggests that any sustained temperature rise could trigger an irreversible melt of the entire southern Greenland ice sheet.

The scientists suggest that the threshold for this calamity could be between 0.8°C above the post-Ice Age norm, and 3.2°C.

“The critical temperature threshold for past Greenland ice sheet decay will likely be surpassed this century”

In fact, because of profligate use of fossil fuels and the release of greenhouse gases into the atmosphere, the planet has already warmed by around 1°C above the level for most of human history, and warming of at least 3.2°C by the end of this century now seems almost certain.

Researchers publish their conclusions with the intention that they should be examined, tested, challenged and perhaps overturned. But widespread alarm at the rate of melt and mass loss in Greenland has been consistent and increasing with the years.

Researchers have repeatedly established that melting each summer is increasing the rate at which glaciers flow and deliver ice to increasingly warmer northern seas, and that this rate of melting has itself begun to accelerate.

So Nil Irvali of the University of Bergen and colleagues took a closer look at the story told by microfossils within cores from the ice and the ocean floor during four interglacial periods over the last 450,000 years.

During those warm spells ocean levels rose dramatically, and in two episodes Greenland’s vanishing ice could have contributed more than five metres in one case, and up to seven metres of sea level rise in the other.

Triggers identified

And in all four of those interglacials, conditions reached temperatures higher than they are right now.

Concern about the stability of the Greenland icecap is no surprise: the Arctic is already warming faster than anywhere else on the planet, thanks to profligate use of fossil fuels and the destruction of the rainforests, and researchers worldwide have begun to identify triggers that feed back into further warming: rain, for instance, in winter; the loss of cloud cover in summer; and the deposits of soot from polar wildfires that darken the snows and enhance the absorption of the sun’s rays.

Years ago, the phrase “at a glacial pace” ceased to be a valid cliché: US scientists clocked one river of ice moving at a rate of 46 metres a day.

So the new study simply confirms fears that already are widespread. What remains to be settled is the point at which the decline of the ice sheet becomes irreversible, the Bergen scientists say. As the ocean warms, this feeds back into the process of melting and triggers longer-term feedbacks.

“The exact point at which these feedbacks are triggered remains equivocal,” say Dr Irvali and her co-authors. “Notably, the critical temperature threshold for past Greenland ice sheet decay will likely be surpassed this century. The duration for which this threshold is exceeded will determine Greenland’s fate.” – Climate News Network

Humans may still have time to stop Greenland’s melting, preventing Arctic ice sheet collapse and devastating sea level rise. But the time left may be short.

LONDON, 30 December, 2019 – It’s still possible, but it’s far from certain: stopping Greenland’s melting can be done, but it must be done soon.

Norwegian and US scientists have taken a close look at the ice age history of Greenland and come to a grim conclusion. All it takes to set the island’s ice cap melting away is a mean sea surface temperature higher than seven degrees Celsius. And the present mean sea surface temperature is already 7.7°C.

Greenland is the northern hemisphere’s single richest store of frozen water: the island’s bedrock holds enough to raise global sea levels by seven metres and drown or wash away the world’s coastal communities, including the great cities of New York and Miami, Shanghai and Kolkata, Amsterdam and London.

And the pattern of geological evidence – outlined in the Proceedings of the National Academy of Sciences – combined with climate models suggests that any sustained temperature rise could trigger an irreversible melt of the entire southern Greenland ice sheet.

The scientists suggest that the threshold for this calamity could be between 0.8°C above the post-Ice Age norm, and 3.2°C.

“The critical temperature threshold for past Greenland ice sheet decay will likely be surpassed this century”

In fact, because of profligate use of fossil fuels and the release of greenhouse gases into the atmosphere, the planet has already warmed by around 1°C above the level for most of human history, and warming of at least 3.2°C by the end of this century now seems almost certain.

Researchers publish their conclusions with the intention that they should be examined, tested, challenged and perhaps overturned. But widespread alarm at the rate of melt and mass loss in Greenland has been consistent and increasing with the years.

Researchers have repeatedly established that melting each summer is increasing the rate at which glaciers flow and deliver ice to increasingly warmer northern seas, and that this rate of melting has itself begun to accelerate.

So Nil Irvali of the University of Bergen and colleagues took a closer look at the story told by microfossils within cores from the ice and the ocean floor during four interglacial periods over the last 450,000 years.

During those warm spells ocean levels rose dramatically, and in two episodes Greenland’s vanishing ice could have contributed more than five metres in one case, and up to seven metres of sea level rise in the other.

Triggers identified

And in all four of those interglacials, conditions reached temperatures higher than they are right now.

Concern about the stability of the Greenland icecap is no surprise: the Arctic is already warming faster than anywhere else on the planet, thanks to profligate use of fossil fuels and the destruction of the rainforests, and researchers worldwide have begun to identify triggers that feed back into further warming: rain, for instance, in winter; the loss of cloud cover in summer; and the deposits of soot from polar wildfires that darken the snows and enhance the absorption of the sun’s rays.

Years ago, the phrase “at a glacial pace” ceased to be a valid cliché: US scientists clocked one river of ice moving at a rate of 46 metres a day.

So the new study simply confirms fears that already are widespread. What remains to be settled is the point at which the decline of the ice sheet becomes irreversible, the Bergen scientists say. As the ocean warms, this feeds back into the process of melting and triggers longer-term feedbacks.

“The exact point at which these feedbacks are triggered remains equivocal,” say Dr Irvali and her co-authors. “Notably, the critical temperature threshold for past Greenland ice sheet decay will likely be surpassed this century. The duration for which this threshold is exceeded will determine Greenland’s fate.” – Climate News Network

Marine climate impacts are intensifying

Fish catches are falling in the Gulf of Maine, Baltic cod are getting smaller. Sharks suffer acid waters’ effects as marine climate impacts grow.

LONDON, 20 December, 2019 – Marine climate impacts are starting to make their mark on marine life at almost every level, according to a range of entirely unrelated scientific studies published in the last month.

Baltic codfish – a valuable commercial catch – have steadily become smaller, scrawnier and less valuable because of the loss of oxygen in ocean waters as a consequence of an increasingly warmer world.

Changes in climate over the last two decades have cost the fishermen of New England their jobs: their numbers have fallen by 16% since 1996 as the total catch has fallen, along with fishermen’s incomes.

The change may be linked to a natural ocean climate cycle, but nobody can be sure the decline will not continue as waters warm in response to ever higher atmospheric levels of carbon dioxide, driven by ever greater use of fossil fuels to power modern economic growth.

That steady rise in carbon dioxide means that marine waters are also becoming steadily more acidic, and this could be bad news for the sharks. Laboratory experiments suggest they can respond to short-term changes in water chemistry, but in the long term increasingly acidic waters can begin to dissolve not just the characteristic skin scales of the shark family, but the teeth as well.

And if environmental change goes on hitting tropical corals and the anemones that co-exist with them, then one of the world’s most iconic and culturally popular species could also disappear: the clownfish sub-family Amphiprioninae may not survive the continued bleaching of the coral reefs. Amphiprion ocellaris swam into the world’s hearts as the much sought-after cartoon character in the 2003 film Finding Nemo.

“We find that Nemo is at the mercy of a habitat that is degrading more and more every year”

Scientists based in the US and Sweden report in the journal Biology Letters that the average weight of specimens of Gadus morhua or the cod fish 40 cms long had dropped from 900 to 600 grams in the last 30 years.

They examined the otoliths or ear stones of 134 individuals trawled in the last months of the Baltic winter to read the evidence from trace elements such as magnesium and manganese and identify the cause: the continued fall in sea water oxygen levels as a consequence of global warming and pollution.

“The cod themselves are telling us through their internal logbooks that they’re affected by hypoxia [reduced oxygen availability], which we know is driven by climate change and nutrient loading,” said Karin Limburg, an ecologist at the State University of New York, who led the study. “Our findings suggest fish are in a worse condition because of hypoxia.”

In the Gulf of Maine, off the US Atlantic coast, catches of fish and shellfish have been falling, and with them the number of people employed in the fishery. Kimberly Oremus of the University of Delaware reports in the Proceedings of the National Academy of Sciences that successive warm winters have hit the catch, and incomes.

Pattern found

She matched decades of climate data, landing figures and sales data to identify a pattern of decline linked principally to a hot-and-cold pattern of change known as the North Atlantic Oscillation.

“New England waters are among the fastest-warming in the world,” she said. “Warmer than average sea surface temperatures have been shown to impact the productivity of lobsters, sea scallops, groundfish and other fisheries important to the region, especially when they are most vulnerable, from spawning through their first year of life.”

The region has 34,000 commercial fishermen, a significant proportion of the 166,000 or so throughout the whole of the US. The oscillation is a shift in ocean temperatures over decades, and catches could improve in decades to come – but marine waters worldwide are warming.

“This is an important signal to incorporate into the fisheries management process,” she said. “We need to figure out what climate is doing to fisheries in order to cope with it.”

Acid hazard

One important part of the marine ecosystem might not in the long run be able to cope: short episodes of hypercapnia, or a dramatic rise in dissolved carbon dioxide, are a feature linked to seasonal oceanic upwellings, and can last for days in some waters before normal ocean chemistry is restored.

In the journal Scientific Reports, European and South Africa researchers offer evidence that though cartilaginous fishes – the huge and varied family to which sharks belong – have evolved to cope with such spells, ever more acidic oceans offer a new hazard.

They caught a number of puffadder shysharks, known to scientists as Haploblepharus edwardsii and a species small enough for laboratory tanks, from shallow waters off South Africa and exposed them to acidic conditions predicted by the year 2300.

The increasingly acid environment was, literally, corrosive. Their specimens lost a quarter of their skin denticles – the shark equivalent of scales. Sharks’ teeth are made of the same biological fabric as the skin, and the implication is that such losses could, in their words “compromise hydrodynamics and skin protection.” In other words, some of the ocean’s most feared predators might have trouble both swimming and feeding.

Poor adapters

Australian and US scientists have more bad news for Nemo, the film star from the clownfish family. Rather than experiment in a laboratory tank, they monitored the numbers and the DNA of real life specimens for decades in Kimbe Bay off Papua-New Guinea. As waters warmed and began to bleach the coral reefs, the anemones that live in the reefs were put at risk.

They report in Ecology Letters that the tiny clownfish that live in the anemone tentacles proved bad at adapting to environmental change. The implication is that, as the coral reefs are lost, many species could be homeless and helpless.

“We find that Nemo is at the mercy of a habitat that is degrading more and more every year,” said Serge Planes of the French National Centre of Scientific Research, and one of the authors.

“To expect a clownfish to genetically adapt at a pace that would allow it to persist is unreasonable.” And Simon Thorrold of the Woods Hole Oceanographic Institution in the US added: “It seems Nemo won’t be able to save himself.” – Climate News Network

Fish catches are falling in the Gulf of Maine, Baltic cod are getting smaller. Sharks suffer acid waters’ effects as marine climate impacts grow.

LONDON, 20 December, 2019 – Marine climate impacts are starting to make their mark on marine life at almost every level, according to a range of entirely unrelated scientific studies published in the last month.

Baltic codfish – a valuable commercial catch – have steadily become smaller, scrawnier and less valuable because of the loss of oxygen in ocean waters as a consequence of an increasingly warmer world.

Changes in climate over the last two decades have cost the fishermen of New England their jobs: their numbers have fallen by 16% since 1996 as the total catch has fallen, along with fishermen’s incomes.

The change may be linked to a natural ocean climate cycle, but nobody can be sure the decline will not continue as waters warm in response to ever higher atmospheric levels of carbon dioxide, driven by ever greater use of fossil fuels to power modern economic growth.

That steady rise in carbon dioxide means that marine waters are also becoming steadily more acidic, and this could be bad news for the sharks. Laboratory experiments suggest they can respond to short-term changes in water chemistry, but in the long term increasingly acidic waters can begin to dissolve not just the characteristic skin scales of the shark family, but the teeth as well.

And if environmental change goes on hitting tropical corals and the anemones that co-exist with them, then one of the world’s most iconic and culturally popular species could also disappear: the clownfish sub-family Amphiprioninae may not survive the continued bleaching of the coral reefs. Amphiprion ocellaris swam into the world’s hearts as the much sought-after cartoon character in the 2003 film Finding Nemo.

“We find that Nemo is at the mercy of a habitat that is degrading more and more every year”

Scientists based in the US and Sweden report in the journal Biology Letters that the average weight of specimens of Gadus morhua or the cod fish 40 cms long had dropped from 900 to 600 grams in the last 30 years.

They examined the otoliths or ear stones of 134 individuals trawled in the last months of the Baltic winter to read the evidence from trace elements such as magnesium and manganese and identify the cause: the continued fall in sea water oxygen levels as a consequence of global warming and pollution.

“The cod themselves are telling us through their internal logbooks that they’re affected by hypoxia [reduced oxygen availability], which we know is driven by climate change and nutrient loading,” said Karin Limburg, an ecologist at the State University of New York, who led the study. “Our findings suggest fish are in a worse condition because of hypoxia.”

In the Gulf of Maine, off the US Atlantic coast, catches of fish and shellfish have been falling, and with them the number of people employed in the fishery. Kimberly Oremus of the University of Delaware reports in the Proceedings of the National Academy of Sciences that successive warm winters have hit the catch, and incomes.

Pattern found

She matched decades of climate data, landing figures and sales data to identify a pattern of decline linked principally to a hot-and-cold pattern of change known as the North Atlantic Oscillation.

“New England waters are among the fastest-warming in the world,” she said. “Warmer than average sea surface temperatures have been shown to impact the productivity of lobsters, sea scallops, groundfish and other fisheries important to the region, especially when they are most vulnerable, from spawning through their first year of life.”

The region has 34,000 commercial fishermen, a significant proportion of the 166,000 or so throughout the whole of the US. The oscillation is a shift in ocean temperatures over decades, and catches could improve in decades to come – but marine waters worldwide are warming.

“This is an important signal to incorporate into the fisheries management process,” she said. “We need to figure out what climate is doing to fisheries in order to cope with it.”

Acid hazard

One important part of the marine ecosystem might not in the long run be able to cope: short episodes of hypercapnia, or a dramatic rise in dissolved carbon dioxide, are a feature linked to seasonal oceanic upwellings, and can last for days in some waters before normal ocean chemistry is restored.

In the journal Scientific Reports, European and South Africa researchers offer evidence that though cartilaginous fishes – the huge and varied family to which sharks belong – have evolved to cope with such spells, ever more acidic oceans offer a new hazard.

They caught a number of puffadder shysharks, known to scientists as Haploblepharus edwardsii and a species small enough for laboratory tanks, from shallow waters off South Africa and exposed them to acidic conditions predicted by the year 2300.

The increasingly acid environment was, literally, corrosive. Their specimens lost a quarter of their skin denticles – the shark equivalent of scales. Sharks’ teeth are made of the same biological fabric as the skin, and the implication is that such losses could, in their words “compromise hydrodynamics and skin protection.” In other words, some of the ocean’s most feared predators might have trouble both swimming and feeding.

Poor adapters

Australian and US scientists have more bad news for Nemo, the film star from the clownfish family. Rather than experiment in a laboratory tank, they monitored the numbers and the DNA of real life specimens for decades in Kimbe Bay off Papua-New Guinea. As waters warmed and began to bleach the coral reefs, the anemones that live in the reefs were put at risk.

They report in Ecology Letters that the tiny clownfish that live in the anemone tentacles proved bad at adapting to environmental change. The implication is that, as the coral reefs are lost, many species could be homeless and helpless.

“We find that Nemo is at the mercy of a habitat that is degrading more and more every year,” said Serge Planes of the French National Centre of Scientific Research, and one of the authors.

“To expect a clownfish to genetically adapt at a pace that would allow it to persist is unreasonable.” And Simon Thorrold of the Woods Hole Oceanographic Institution in the US added: “It seems Nemo won’t be able to save himself.” – Climate News Network

Food at risk as third of plants face extinction

More than a third of the world’s plants are so rare they face extinction. In a warmer world, that would leave supplies of food at risk.

LONDON, 17 December, 2019 – Botanists have made a new census of terrestrial plants – only to find that with nearly 40% of them rare, or extremely rare, this may put food at risk.

And a second team of researchers, in a separate study, has established that some of these rare or vanishing species could include the wild relatives of some of the planet’s most popular vegetables.

The two studies matter. The first underlines yet another reason for new and determined conservation strategies to preserve the extraordinary natural variety and richness of life – the shorthand word that scientists use is biodiversity – already under pressure from the explosion in human numbers, the destruction of natural habitats and the looming catastrophe of climate change driven by rapidly rising global temperatures.

And the second study is simply a matter of the next lunch or dinner: many rare plants are survivors with the resources to adapt to change. In a fast-changing world, crop breeders may need to go back to the wild relatives to look for the genes that will keep the commercial carrots, courgettes, pumpkins and chilli peppers on the grocery shelves.

US scientists and international colleagues report in the journal Science Advances that they worked for 10 years and compiled 20 million observational records to establish a simple plant census: the forests, grasslands, scrublands, tundra and swamps of the wild world are home to about 435,000 unique plant species.

“The wild relatives of crops are one of the key tools used to breed crops adapted to difficult conditions. Some of them are sure to disappear from their natural habitats without urgent action”

And of this huge number, a surprising 36.5% are “exceedingly rare.” By this, researchers mean that these species have been observed and recorded no more than five times in the last 300 years of systematic botanical research.

“According to ecological and evolutionary theory, we’d expect many species to be rare, but the actual observed number we found was pretty startling,” said Brian Enquist of the University of Arizona, who led the consortium. “There are many more rare species than we expected.”

The rare species were most likely to be clustered in what ecologists call hotspots: the northern Andes in South America, Costa Rica, South Africa, Madagascar and south-east Asia.

What these places have in common is that, over millions of years, they have maintained stable climates, and as the glaciers retreated at the end of the last Ice Age, these tropical mountains and valleys provided refuge for life’s variety.

But these survivors may not enjoy a stable future, as ever higher levels of greenhouse gases are spilled into the atmosphere from human use of fossil fuels, and global temperatures continue to rise, and as human communities expand into what was once wilderness.

Significant loss ahead

“In many of these regions, there’s increasing human activity such as agriculture, cities and towns, land use and clearing,” said Professor Enquist.

“So that’s not exactly the best of news. If nothing is done, this all indicates that there will be a significant reduction in biodiversity – mainly in rare species – because their low numbers makes them more prone to extinction.”

Humans depend on the natural world for survival: biodiversity – plants, fungi, mammals, birds, fish, amphibians, reptiles and so on – provides all human nourishment, most of the medicines, fuels, fabrics and textiles that warm and shelter 7.7bn people, and at the same time maintains supplies of water, air, crop pollinators and so on.

But new research in the journal Plants, People, Planet confirms once again that many of the wild ancestors and cousins of the crops that nourish billions could be at risk.

And these wild relatives – which have survived climate shifts over millions of years – represent a vital resource for plant breeders anxious to cope with rapid global heating.

Unpreserved

The latest study confirms that 65% of wild pumpkins and more than 95% of wild chilli peppers are not formally preserved in any gene banks protected by conservation scientists.

“The wild relatives of crops are one of the key tools used to breed crops adapted to hotter, colder, drier, wetter, saltier and other difficult conditions,” said Colin Khoury of the International Centre for Tropical Agriculture.

“But they are impacted by habitat destruction, over-harvesting, climate change, pollution, invasive species and more. Some of them are sure to disappear from their natural habitats without urgent action.”

Dr Khoury and his colleagues have prepared a series of detailed maps of the range and distribution of the wild relatives of a range of important food species: the aim is to focus on the most effective kinds of protection for what, literally, could become tomorrow’s lunch in a world of rapid change.

“If they disappear, they are gone,” said Dr Khoury. “Extinction is forever, which is a loss not only in terms of their evolution and persistence on the planet, but also a loss to the future of our food.” – Climate News Network

More than a third of the world’s plants are so rare they face extinction. In a warmer world, that would leave supplies of food at risk.

LONDON, 17 December, 2019 – Botanists have made a new census of terrestrial plants – only to find that with nearly 40% of them rare, or extremely rare, this may put food at risk.

And a second team of researchers, in a separate study, has established that some of these rare or vanishing species could include the wild relatives of some of the planet’s most popular vegetables.

The two studies matter. The first underlines yet another reason for new and determined conservation strategies to preserve the extraordinary natural variety and richness of life – the shorthand word that scientists use is biodiversity – already under pressure from the explosion in human numbers, the destruction of natural habitats and the looming catastrophe of climate change driven by rapidly rising global temperatures.

And the second study is simply a matter of the next lunch or dinner: many rare plants are survivors with the resources to adapt to change. In a fast-changing world, crop breeders may need to go back to the wild relatives to look for the genes that will keep the commercial carrots, courgettes, pumpkins and chilli peppers on the grocery shelves.

US scientists and international colleagues report in the journal Science Advances that they worked for 10 years and compiled 20 million observational records to establish a simple plant census: the forests, grasslands, scrublands, tundra and swamps of the wild world are home to about 435,000 unique plant species.

“The wild relatives of crops are one of the key tools used to breed crops adapted to difficult conditions. Some of them are sure to disappear from their natural habitats without urgent action”

And of this huge number, a surprising 36.5% are “exceedingly rare.” By this, researchers mean that these species have been observed and recorded no more than five times in the last 300 years of systematic botanical research.

“According to ecological and evolutionary theory, we’d expect many species to be rare, but the actual observed number we found was pretty startling,” said Brian Enquist of the University of Arizona, who led the consortium. “There are many more rare species than we expected.”

The rare species were most likely to be clustered in what ecologists call hotspots: the northern Andes in South America, Costa Rica, South Africa, Madagascar and south-east Asia.

What these places have in common is that, over millions of years, they have maintained stable climates, and as the glaciers retreated at the end of the last Ice Age, these tropical mountains and valleys provided refuge for life’s variety.

But these survivors may not enjoy a stable future, as ever higher levels of greenhouse gases are spilled into the atmosphere from human use of fossil fuels, and global temperatures continue to rise, and as human communities expand into what was once wilderness.

Significant loss ahead

“In many of these regions, there’s increasing human activity such as agriculture, cities and towns, land use and clearing,” said Professor Enquist.

“So that’s not exactly the best of news. If nothing is done, this all indicates that there will be a significant reduction in biodiversity – mainly in rare species – because their low numbers makes them more prone to extinction.”

Humans depend on the natural world for survival: biodiversity – plants, fungi, mammals, birds, fish, amphibians, reptiles and so on – provides all human nourishment, most of the medicines, fuels, fabrics and textiles that warm and shelter 7.7bn people, and at the same time maintains supplies of water, air, crop pollinators and so on.

But new research in the journal Plants, People, Planet confirms once again that many of the wild ancestors and cousins of the crops that nourish billions could be at risk.

And these wild relatives – which have survived climate shifts over millions of years – represent a vital resource for plant breeders anxious to cope with rapid global heating.

Unpreserved

The latest study confirms that 65% of wild pumpkins and more than 95% of wild chilli peppers are not formally preserved in any gene banks protected by conservation scientists.

“The wild relatives of crops are one of the key tools used to breed crops adapted to hotter, colder, drier, wetter, saltier and other difficult conditions,” said Colin Khoury of the International Centre for Tropical Agriculture.

“But they are impacted by habitat destruction, over-harvesting, climate change, pollution, invasive species and more. Some of them are sure to disappear from their natural habitats without urgent action.”

Dr Khoury and his colleagues have prepared a series of detailed maps of the range and distribution of the wild relatives of a range of important food species: the aim is to focus on the most effective kinds of protection for what, literally, could become tomorrow’s lunch in a world of rapid change.

“If they disappear, they are gone,” said Dr Khoury. “Extinction is forever, which is a loss not only in terms of their evolution and persistence on the planet, but also a loss to the future of our food.” – Climate News Network

Ultra-fast computers could avert global disaster

The world can be saved. It needs global co-operation, careful research and the building of ultra-fast computers.

LONDON, 13 December, 2019 – The way to steer the planet safely away from overwhelming climate crisis may sound familiar, though it’s staggeringly ambitious: just use incredibly powerful and ultra-fast computers.

Studies in two separate journals have called for new thinking about global change. One warns that only a genuine accommodation with nature can save humankind from catastrophic change. The other argues that present understanding of the trajectories of global heating is so uncertain that what is needed is a global co-operation to deliver what scientists call exascale supercomputer climate modelling: exascale means calculations at rates of a billion billion operations a second.

There’s a snag: nobody has yet built a working exascale computer, though several groups hope to succeed within a few years. But when it’s done it could transform the prospects of life on Earth.

“We cannot save the planet – and ourselves – until we understand how tightly woven people and the natural benefits that allow us to survive are,” said Jianguo Liu of Michigan State University, one of the authors of a paper in the journal Science.

“We have learned new ways to understand these connections, even as they spread across the globe. This strategy has given us the power to understand the full scope of the problem, which allows us to find true solutions.”

“Human actions are causing the fabric of life to unravel, posing serious risks for the quality of life of people”

And Tim Palmer of Oxford University, an author of a perspective paper in the Proceedings of the National Academy of Sciences, has called for a new and international investment in sophisticated climate modelling, exploiting a new generation of computers, in much the same way that physicists at CERN in Geneva co-operated to explore the sequence of events in the first microsecond of creation.

“By comparison with new particle colliders or space telescopes, the amount needed, maybe around $100 million a year, is very modest indeed. In addition, the benefit/cost ratio to society of having a much clearer picture of the dangers we are facing in the coming decades by our ongoing actions, seems extraordinarily large,” he said.

“To be honest, all is needed is the will to work together across nations, on such a project. Then it will happen.”

The point made by authors of the Science study is that humankind depends acutely on the natural world for at least 18 direct benefits: these include pollination and the dispersal of seeds, the regulation of clean air, and of climate, and of fresh water, the protection of topsoils, the control of potential pests and diseases, the supplies of energy, food and animal fodder, the supplies of materials and fabrics and yields of new medicines and biochemical compounds.

Massive change

“Human actions are causing the fabric of life to unravel, posing serious risks for the quality of life of people”, the authors warn.

“Human actions have directly altered at least 70% of land surface; 66% of ocean surface is experiencing cumulative impacts; around 85% of wetland area has been lost since the 1700s and 77% of rivers longer than 1000 km no longer flow freely from source to sea.”

There was a need for “transformative action” on a global scale to address root economic, social and technological causes and to avert catastrophic decline of the living world. “Although the challenge is formidable, every delay will make the task harder”, they warn.

But in a world of rapid change – with species at increasing risk of extinction and global heating about to trigger catastrophic climate change – there is still the challenge of working out what the implications of any change might be.

The argument is that human society must change, and so too must the scientific community. Climate modelling might deliver broad answers, but researchers would still need to be sure what might work best in any particular circumstances, and that would require new and vastly more complex levels of mathematical calculation and data interpretation.

Space-race urgency

Professor Palmer and his colleague Bjorn Stevens of the Max Planck Institute for Meteorology in Hamburg call for better understanding of the need for change.

“What is needed is the urgency of the space race aimed, not at the Moon or Mars, but rather toward harnessing the promise of exascale supercomputing to reliably simulate Earth’s regional climate (and associated extremes) globally”, they argue.

“This will only be possible if the broader climate science community begins to articulate its dissatisfaction with business as usual – not just among themselves, but externally to those who seek to use the models for business, policy, or humanitarian reasons.

“Failing to do so becomes an ethical issue in that it saddles us with the status quo: a strategy that hopes, against all evidence, to surmount the abyss between scientific capability and societal needs.” – Climate News Network

The world can be saved. It needs global co-operation, careful research and the building of ultra-fast computers.

LONDON, 13 December, 2019 – The way to steer the planet safely away from overwhelming climate crisis may sound familiar, though it’s staggeringly ambitious: just use incredibly powerful and ultra-fast computers.

Studies in two separate journals have called for new thinking about global change. One warns that only a genuine accommodation with nature can save humankind from catastrophic change. The other argues that present understanding of the trajectories of global heating is so uncertain that what is needed is a global co-operation to deliver what scientists call exascale supercomputer climate modelling: exascale means calculations at rates of a billion billion operations a second.

There’s a snag: nobody has yet built a working exascale computer, though several groups hope to succeed within a few years. But when it’s done it could transform the prospects of life on Earth.

“We cannot save the planet – and ourselves – until we understand how tightly woven people and the natural benefits that allow us to survive are,” said Jianguo Liu of Michigan State University, one of the authors of a paper in the journal Science.

“We have learned new ways to understand these connections, even as they spread across the globe. This strategy has given us the power to understand the full scope of the problem, which allows us to find true solutions.”

“Human actions are causing the fabric of life to unravel, posing serious risks for the quality of life of people”

And Tim Palmer of Oxford University, an author of a perspective paper in the Proceedings of the National Academy of Sciences, has called for a new and international investment in sophisticated climate modelling, exploiting a new generation of computers, in much the same way that physicists at CERN in Geneva co-operated to explore the sequence of events in the first microsecond of creation.

“By comparison with new particle colliders or space telescopes, the amount needed, maybe around $100 million a year, is very modest indeed. In addition, the benefit/cost ratio to society of having a much clearer picture of the dangers we are facing in the coming decades by our ongoing actions, seems extraordinarily large,” he said.

“To be honest, all is needed is the will to work together across nations, on such a project. Then it will happen.”

The point made by authors of the Science study is that humankind depends acutely on the natural world for at least 18 direct benefits: these include pollination and the dispersal of seeds, the regulation of clean air, and of climate, and of fresh water, the protection of topsoils, the control of potential pests and diseases, the supplies of energy, food and animal fodder, the supplies of materials and fabrics and yields of new medicines and biochemical compounds.

Massive change

“Human actions are causing the fabric of life to unravel, posing serious risks for the quality of life of people”, the authors warn.

“Human actions have directly altered at least 70% of land surface; 66% of ocean surface is experiencing cumulative impacts; around 85% of wetland area has been lost since the 1700s and 77% of rivers longer than 1000 km no longer flow freely from source to sea.”

There was a need for “transformative action” on a global scale to address root economic, social and technological causes and to avert catastrophic decline of the living world. “Although the challenge is formidable, every delay will make the task harder”, they warn.

But in a world of rapid change – with species at increasing risk of extinction and global heating about to trigger catastrophic climate change – there is still the challenge of working out what the implications of any change might be.

The argument is that human society must change, and so too must the scientific community. Climate modelling might deliver broad answers, but researchers would still need to be sure what might work best in any particular circumstances, and that would require new and vastly more complex levels of mathematical calculation and data interpretation.

Space-race urgency

Professor Palmer and his colleague Bjorn Stevens of the Max Planck Institute for Meteorology in Hamburg call for better understanding of the need for change.

“What is needed is the urgency of the space race aimed, not at the Moon or Mars, but rather toward harnessing the promise of exascale supercomputing to reliably simulate Earth’s regional climate (and associated extremes) globally”, they argue.

“This will only be possible if the broader climate science community begins to articulate its dissatisfaction with business as usual – not just among themselves, but externally to those who seek to use the models for business, policy, or humanitarian reasons.

“Failing to do so becomes an ethical issue in that it saddles us with the status quo: a strategy that hopes, against all evidence, to surmount the abyss between scientific capability and societal needs.” – Climate News Network

Racing ice loss strips Greenland of mass

Greenland is shrinking, losing ice seven times faster than a generation ago. Scientists have taken a new and ominous measure of polar loss.

LONDON, 11 December, 2019 – Greenland – the largest body of frozen water in the northern hemisphere – is now losing ice seven times faster than it did during the last decade of the 20th century.

From 1990 to 1999, the Greenland ice sheet spilled an average of 33 billion tonnes of ice into the oceans every year. In the last decade the rate of loss has accelerated to an average of 254 billion tonnes a year.

Altogether, the Greenland ice cap has surrendered 3.8 trillion tonnes of ice since 1992. This alone is enough to raise global sea levels by 10.6 millimetres.

Glaciers and icecaps are in retreat in two hemispheres, and on every continent, as a consequence of profligate human combustion of fossil fuels, to drive up greenhouse gas levels in the atmosphere, and accelerate global heating.

Devastating

“As a rule of thumb, for every centimetre rise in global sea level another six million people are exposed to coastal flooding around the planet”, said Andrew Shepherd of the University of Leeds in the UK.

“On current trends, Greenland ice melting will cause 100 million people to be flooded each year by the end of the century, so 400 million in total due to all sea level rise. These are not unlikely events of small impacts; they are happening and will be devastating for coastal communities.”

Professor Shepherd is one of 96 polar scientists from 50 international organisations in a partnership known by the cumbrous name IMBIE, which stands for Ice Sheet Mass Balance Intercomparison Exercise. They made this assessment, based on data from 11 satellite missions and 26 separate surveys between 1992 and 2018, and published their conclusions in the journal Nature.

Greenland is not just the largest ice mass in the Arctic, it is probably the polar landscape studied for the longest time, and the most intensively.
Researchers have monitored the rate of summer melt, tried to match increases with other phenomena – for instance the darkening of snow by sub-Arctic wildfires – and tried to explore the mechanisms by which volumes of water that might in the past have frozen again each winter now accelerate glacier melt and escape into the ocean.

No surprise

The icecap is so big that – were it all to melt, which would take centuries – it would raise sea levels by as much as seven metres.

The news of a dramatic increase in rates of melting is not a surprise, and certainly not to the people who live in Greenland.

In 2013, the Intergovernmental Panel on Climate Change warned that global sea levels would rise by 60 cms by 2100. What matters about the latest survey is that it confirms the worst fears of many climate scientists and suggests that sea level rise is heading for the high end of the 2013 projections.

That is, by the end of this century, seas could have risen by nearer 70 cms. Around 100 million people already live at levels below the highest tides: the numbers increasingly at risk may be much higher.

The same study also explores the rates of change. Although the warmest years ever recorded have happened in the last century, as fossil fuel emissions and rainforest losses have continued to increase, the impact of global heating has been uneven.

“Our project is a great example of the importance of international collaboration to tackle problems that are global in scale”

The greatest loss of Greenland ice in any one year was in 2011, when the island lost 335 billion tonnes. Nor does the survey include all the data from 2019, and researchers could yet find that this summer’s ice loss has set new records.

Greenland’s loss of ice has been mirrored by continued loss of sea ice during successive Arctic summers, and since the world’s seasonal weather patterns have – for most of human history – been driven by the temperature difference between tropics and poles, the continued loss of ice will almost certainly impose worldwide costs in harvest losses, freak storms, droughts, wildfires and of course coastal flooding.

And ultimately, the study is a test of computer simulations of change in the northern hemisphere. Climate models have consistently predicted polar ice loss and sea level rise. But the latest study is a confirmation that such loss is real, and beyond argument.

“While computer simulation allows us to make projections from climate change scenarios, the satellite measurements provide prima facie, rather irrefutable evidence,” said Erik Ivins of Nasa’s Jet Propulsion Laboratory in California, and a co-author.

“Our project is a great example of the importance of international collaboration to tackle problems that are global in scale.” – Climate News Network

Greenland is shrinking, losing ice seven times faster than a generation ago. Scientists have taken a new and ominous measure of polar loss.

LONDON, 11 December, 2019 – Greenland – the largest body of frozen water in the northern hemisphere – is now losing ice seven times faster than it did during the last decade of the 20th century.

From 1990 to 1999, the Greenland ice sheet spilled an average of 33 billion tonnes of ice into the oceans every year. In the last decade the rate of loss has accelerated to an average of 254 billion tonnes a year.

Altogether, the Greenland ice cap has surrendered 3.8 trillion tonnes of ice since 1992. This alone is enough to raise global sea levels by 10.6 millimetres.

Glaciers and icecaps are in retreat in two hemispheres, and on every continent, as a consequence of profligate human combustion of fossil fuels, to drive up greenhouse gas levels in the atmosphere, and accelerate global heating.

Devastating

“As a rule of thumb, for every centimetre rise in global sea level another six million people are exposed to coastal flooding around the planet”, said Andrew Shepherd of the University of Leeds in the UK.

“On current trends, Greenland ice melting will cause 100 million people to be flooded each year by the end of the century, so 400 million in total due to all sea level rise. These are not unlikely events of small impacts; they are happening and will be devastating for coastal communities.”

Professor Shepherd is one of 96 polar scientists from 50 international organisations in a partnership known by the cumbrous name IMBIE, which stands for Ice Sheet Mass Balance Intercomparison Exercise. They made this assessment, based on data from 11 satellite missions and 26 separate surveys between 1992 and 2018, and published their conclusions in the journal Nature.

Greenland is not just the largest ice mass in the Arctic, it is probably the polar landscape studied for the longest time, and the most intensively.
Researchers have monitored the rate of summer melt, tried to match increases with other phenomena – for instance the darkening of snow by sub-Arctic wildfires – and tried to explore the mechanisms by which volumes of water that might in the past have frozen again each winter now accelerate glacier melt and escape into the ocean.

No surprise

The icecap is so big that – were it all to melt, which would take centuries – it would raise sea levels by as much as seven metres.

The news of a dramatic increase in rates of melting is not a surprise, and certainly not to the people who live in Greenland.

In 2013, the Intergovernmental Panel on Climate Change warned that global sea levels would rise by 60 cms by 2100. What matters about the latest survey is that it confirms the worst fears of many climate scientists and suggests that sea level rise is heading for the high end of the 2013 projections.

That is, by the end of this century, seas could have risen by nearer 70 cms. Around 100 million people already live at levels below the highest tides: the numbers increasingly at risk may be much higher.

The same study also explores the rates of change. Although the warmest years ever recorded have happened in the last century, as fossil fuel emissions and rainforest losses have continued to increase, the impact of global heating has been uneven.

“Our project is a great example of the importance of international collaboration to tackle problems that are global in scale”

The greatest loss of Greenland ice in any one year was in 2011, when the island lost 335 billion tonnes. Nor does the survey include all the data from 2019, and researchers could yet find that this summer’s ice loss has set new records.

Greenland’s loss of ice has been mirrored by continued loss of sea ice during successive Arctic summers, and since the world’s seasonal weather patterns have – for most of human history – been driven by the temperature difference between tropics and poles, the continued loss of ice will almost certainly impose worldwide costs in harvest losses, freak storms, droughts, wildfires and of course coastal flooding.

And ultimately, the study is a test of computer simulations of change in the northern hemisphere. Climate models have consistently predicted polar ice loss and sea level rise. But the latest study is a confirmation that such loss is real, and beyond argument.

“While computer simulation allows us to make projections from climate change scenarios, the satellite measurements provide prima facie, rather irrefutable evidence,” said Erik Ivins of Nasa’s Jet Propulsion Laboratory in California, and a co-author.

“Our project is a great example of the importance of international collaboration to tackle problems that are global in scale.” – Climate News Network

Greenland ice melt feeds glacier instability

In a runaway effect, the Greenland ice melt lets surface water gurgle down to the bedrock – and at unexpected speeds.

LONDON, 6 December, 2019 – British scientists have caught a huge ice sheet in the act of draining away, with significant effects on its surroundings: they have seen what happens to the water created by the Greenland ice melt.

For the first time – and with help from drones – researchers have witnessed water flowing at a million cubic metres an hour from the surface of ice sheets through caverns in the ice and down to the glacial bedrock.

The study does not change the big picture of increasingly rapid melt as greenhouse gases build up in the atmosphere, and ever more of the northern hemisphere’s biggest ice cap flows downhill to raise global sea levels.

But it does throw light on the mechanisms by which glaciers turn to sea water, and it does suggest that many estimates of melt rate so far might prove to be under-estimates.

Greenland is the planet’s second largest ice sheet and the biggest single contributor to global sea level rise. Researchers have been alarmed for years about the increasing rate of summer melt and the accelerating speed of what had once been imperceptible glacial flows.

“These glaciers are already moving quite fast, so the effect of the lakes may not appear as dramatic as on slower-moving glaciers elsewhere, but the overall effect is in fact very significant”

And researchers from the universities of Cambridge, Aberystwyth and Lancaster have now been able to put a measure on water surface loss.

They report in the Proceedings of the National Academy of Sciences that they used custom-built aerial drones and complex computer modelling to work out how fractures form below vast lakes of meltwater that collect on the surface of the Store Glacier on the island’s northwestern sheet.

They watched splits form in the glacial ice, to suddenly open up an escape route for the supraglacial pool. As they watched, such fractures became caverns called moulins, down which in one case five million cubic metres of water – think of 2,000 Olympic swimming pools – flowed in just five hours.

The ice of the glacier is typically a kilometre thick, so the scientists may have observed the planet’s longest waterfall. And as the ice drained away to the bottom of the ice sheet, it may have served as a lubricant to speed up glacier flow over the bedrock.

The ice sheet lifted by half a metre, presumably in response to the sub-surface flood, and four kilometres downstream glacial speed picked up from a speed of two metres to more than five metres a day.

Daily billion-tonne loss

“It’s possible we’ve under-estimated the effects of these glaciers on the overall instability of the Greenland ice sheet. It’s a rare thing to observe these fast-draining lakes – we were lucky to be in the right place at the right time,” said Tom Chudley, of the Scott Polar Research Institute in Cambridge, one of the authors.

Until now, scientists have been able to estimate glacial flow and surface melt only by satellite studies – which reveal little of the detail – or direct on-the-ground measurement under conditions that are difficult even in good weather.

But even with these constraints researchers have been able to calculate the shrinkage of the Greenland ice sheet at the rate of a billion tonnes a day, as temperatures rise in response to ever-increasing use of fossil fuels around the globe.

The next step is to deploy drilling equipment for a closer look at how the water gets below the glacier to reach the bedrock, and calculate how the ice sheet may change not just over hours but over the coming decades as well.

“These glaciers are already moving quite fast, so the effect of the lakes may not appear as dramatic as on slower-moving glaciers elsewhere,” said Poul Christofferson, who led the project, “but the overall effect is in fact very significant.” – Climate News Network

In a runaway effect, the Greenland ice melt lets surface water gurgle down to the bedrock – and at unexpected speeds.

LONDON, 6 December, 2019 – British scientists have caught a huge ice sheet in the act of draining away, with significant effects on its surroundings: they have seen what happens to the water created by the Greenland ice melt.

For the first time – and with help from drones – researchers have witnessed water flowing at a million cubic metres an hour from the surface of ice sheets through caverns in the ice and down to the glacial bedrock.

The study does not change the big picture of increasingly rapid melt as greenhouse gases build up in the atmosphere, and ever more of the northern hemisphere’s biggest ice cap flows downhill to raise global sea levels.

But it does throw light on the mechanisms by which glaciers turn to sea water, and it does suggest that many estimates of melt rate so far might prove to be under-estimates.

Greenland is the planet’s second largest ice sheet and the biggest single contributor to global sea level rise. Researchers have been alarmed for years about the increasing rate of summer melt and the accelerating speed of what had once been imperceptible glacial flows.

“These glaciers are already moving quite fast, so the effect of the lakes may not appear as dramatic as on slower-moving glaciers elsewhere, but the overall effect is in fact very significant”

And researchers from the universities of Cambridge, Aberystwyth and Lancaster have now been able to put a measure on water surface loss.

They report in the Proceedings of the National Academy of Sciences that they used custom-built aerial drones and complex computer modelling to work out how fractures form below vast lakes of meltwater that collect on the surface of the Store Glacier on the island’s northwestern sheet.

They watched splits form in the glacial ice, to suddenly open up an escape route for the supraglacial pool. As they watched, such fractures became caverns called moulins, down which in one case five million cubic metres of water – think of 2,000 Olympic swimming pools – flowed in just five hours.

The ice of the glacier is typically a kilometre thick, so the scientists may have observed the planet’s longest waterfall. And as the ice drained away to the bottom of the ice sheet, it may have served as a lubricant to speed up glacier flow over the bedrock.

The ice sheet lifted by half a metre, presumably in response to the sub-surface flood, and four kilometres downstream glacial speed picked up from a speed of two metres to more than five metres a day.

Daily billion-tonne loss

“It’s possible we’ve under-estimated the effects of these glaciers on the overall instability of the Greenland ice sheet. It’s a rare thing to observe these fast-draining lakes – we were lucky to be in the right place at the right time,” said Tom Chudley, of the Scott Polar Research Institute in Cambridge, one of the authors.

Until now, scientists have been able to estimate glacial flow and surface melt only by satellite studies – which reveal little of the detail – or direct on-the-ground measurement under conditions that are difficult even in good weather.

But even with these constraints researchers have been able to calculate the shrinkage of the Greenland ice sheet at the rate of a billion tonnes a day, as temperatures rise in response to ever-increasing use of fossil fuels around the globe.

The next step is to deploy drilling equipment for a closer look at how the water gets below the glacier to reach the bedrock, and calculate how the ice sheet may change not just over hours but over the coming decades as well.

“These glaciers are already moving quite fast, so the effect of the lakes may not appear as dramatic as on slower-moving glaciers elsewhere,” said Poul Christofferson, who led the project, “but the overall effect is in fact very significant.” – Climate News Network

Worst hurricanes both more frequent and harmful

The worst hurricanes are increasing. It’s not just that there are more potential victims than before. There are also more disastrous storms.

LONDON, 3 December, 2019 – Danish researchers have settled a problem of US disaster accounting, confirming that in the last century North America’s worst hurricanes have become three times more frequent – and significantly more destructive.

Such calculations sound as though they ought to be simple. They are not. In 1900, the entire population of the planet was about 1.6 billion people, most of whom lived in rural areas. By 2018, global population had reached 7.5 billion, and more than half of the world was concentrated in cities. In effect, any hurricane would threaten more victims, and there would be more, and more expensive, property to be destroyed.

So the damage from hurricanes would tend always to rise, and the count of destructive hurricanes would grow, because any violent windstorm would be more likely to slam into an urban area rather than sweep over a few farms.

Tropical cyclones, typhoons and hurricanes start at sea, as sea surface temperatures rise. With ever-increasing global temperatures, driven by profligate combustion of fossil fuels, more hurricanes would be expected, with higher windspeeds and ever-greater burdens of rain to bring disastrous floods as well as severe damage.

“The frequency of the most damaging hurricanes has increased at the rate of 350% per century”

But it is harder to show that the climate crisis is intrinsically more dangerous, even though windstorm damage is on the rise. Researchers tend to use economic accounting to try to work out what a hurricane in, for example 1950, would cost if it swept in from the ocean today.

Hurricanes are the costliest natural disasters in the US. Scientists at the Niels Bohr Institute in Copenhagen set about making their comparisons in a new way. Rather than match financial losses on a case by case basis, they tried to calculate how large an area would have to be completely destroyed to account for a particular financial loss.

They extended this “area of total destruction” accounting back to 1900, to see what the new comparison approach would reveal.

And, they report in the Proceedings of the National Academy of Sciences, they found what they call “an emergent positive trend in damage, which we attribute to a detectable change in extreme storms due to global warming.” And they add: “The frequency of the most damaging hurricanes has increased at the rate of 350% per century.” – Climate News Network.

The worst hurricanes are increasing. It’s not just that there are more potential victims than before. There are also more disastrous storms.

LONDON, 3 December, 2019 – Danish researchers have settled a problem of US disaster accounting, confirming that in the last century North America’s worst hurricanes have become three times more frequent – and significantly more destructive.

Such calculations sound as though they ought to be simple. They are not. In 1900, the entire population of the planet was about 1.6 billion people, most of whom lived in rural areas. By 2018, global population had reached 7.5 billion, and more than half of the world was concentrated in cities. In effect, any hurricane would threaten more victims, and there would be more, and more expensive, property to be destroyed.

So the damage from hurricanes would tend always to rise, and the count of destructive hurricanes would grow, because any violent windstorm would be more likely to slam into an urban area rather than sweep over a few farms.

Tropical cyclones, typhoons and hurricanes start at sea, as sea surface temperatures rise. With ever-increasing global temperatures, driven by profligate combustion of fossil fuels, more hurricanes would be expected, with higher windspeeds and ever-greater burdens of rain to bring disastrous floods as well as severe damage.

“The frequency of the most damaging hurricanes has increased at the rate of 350% per century”

But it is harder to show that the climate crisis is intrinsically more dangerous, even though windstorm damage is on the rise. Researchers tend to use economic accounting to try to work out what a hurricane in, for example 1950, would cost if it swept in from the ocean today.

Hurricanes are the costliest natural disasters in the US. Scientists at the Niels Bohr Institute in Copenhagen set about making their comparisons in a new way. Rather than match financial losses on a case by case basis, they tried to calculate how large an area would have to be completely destroyed to account for a particular financial loss.

They extended this “area of total destruction” accounting back to 1900, to see what the new comparison approach would reveal.

And, they report in the Proceedings of the National Academy of Sciences, they found what they call “an emergent positive trend in damage, which we attribute to a detectable change in extreme storms due to global warming.” And they add: “The frequency of the most damaging hurricanes has increased at the rate of 350% per century.” – Climate News Network.

Conservation pays its way handsomely

Money does grow on trees. The conservation of a native forest is natural capital, its cash value often reaching trillions of dollars.

LONDON, 2 December, 2019 – More than 400 scientists in Brazil have once again established that conservation pays: landscapes and people are richer for the native vegetation preserved on rural properties.

They calculate that 270 million hectares (667m acres) of natural forest, scrub, marsh and grassland contained in Brazil’s legal reserves are worth US$1.5 trillion (£1.7tn) a year to the nation.

Natural wilderness pays its way by providing a steady supply of natural crop pollinators and pest controls, by seamlessly managing rainfall and water run-off, and by maintaining soil quality, the researchers argue in a new study in the journal Perspectives in Ecology and Conservation.

“The paper is meant to show that preserving native vegetation isn’t an obstacle to social and economic development but part of the solution. It’s one of the drivers of sustainable development in Brazil and diverges from what was done in Europe 500 years ago, when the level of environmental awareness was different”, said Jean Paul Metzger, an ecologist at the University of São Paulo, who leads the signatories.

“Brazil conserves a great deal, protecting over 60% of its vegetation cover, and has strict legislation. It’s ranked 30th by the World Bank, behind Sweden and Finland, which protect approximately 70%. However, we must call attention to the fact that conservation isn’t bad,” said Professor Metzger.

Protection maintained

Brazilian law requires rural landowners to leave forest cover untouched on a percentage of their property: in the Amazon region as much as 80%; in other regions as little as 20%. But these protected areas shelter a third of the nation’s natural vegetation.

A bill that proposed to weaken or eliminate the Legal Reserve requirement went before the Brazilian Senate in 2019. Had it passed, it could have led to the loss altogether of 270 million hectares of native vegetation.

The bill has since been withdrawn, but a small army of scientists – including 371 researchers in 79 Brazilian laboratories, universities and institutions – have responded with a study that attempts to set a cash value to simply maintaining the natural capital of the wilderness.

Brazil is home to one of the world’s great tropical rainforests, and to one of the world’s richest centres of biodiversity. The global climate crisis is already taking its toll of the forest canopy in the form of drought and fire. But under new national leadership there have been fears that even more forest could be at risk.

“Preserving native vegetation isn’t an obstacle to social and economic development but part of the solution. It’s one of the drivers of sustainable development in Brazil”

The cash-value case for conservation has been made, and made repeatedly. Studies have confirmed that agribusiness monocultures – vast tracts devoted entirely to one crop and only one crop – are not sustainable: animal pollinators can make the best of the flowering season but then have no alternative sources of food for the rest of the year.

Other researchers have separately established that the loss of natural forest can be far more costly and economically damaging than anybody had expected; and that, conversely, conserved and undisturbed wilderness actually delivers wealth on a sustained basis for national and regional economies. But farmers concerned with immediate profits might not be so conscious of the long-term rewards of conservation.

“It’s an important paper because it presents sound information that can be used to refute the arguments of those who want to change the Brazilian Forest Code and do away with the legal reserve requirement”, said Carlos Joly of the Sao Paulo Research Foundation, and one of the signatories.

And his colleague Paulo Artaxo said: “Farmers sometimes take a short-term view that focuses on three or four years of personal profit, but the nation is left with enormous losses. This mindset should go. The paper makes that very clear.” – Climate News Network

Money does grow on trees. The conservation of a native forest is natural capital, its cash value often reaching trillions of dollars.

LONDON, 2 December, 2019 – More than 400 scientists in Brazil have once again established that conservation pays: landscapes and people are richer for the native vegetation preserved on rural properties.

They calculate that 270 million hectares (667m acres) of natural forest, scrub, marsh and grassland contained in Brazil’s legal reserves are worth US$1.5 trillion (£1.7tn) a year to the nation.

Natural wilderness pays its way by providing a steady supply of natural crop pollinators and pest controls, by seamlessly managing rainfall and water run-off, and by maintaining soil quality, the researchers argue in a new study in the journal Perspectives in Ecology and Conservation.

“The paper is meant to show that preserving native vegetation isn’t an obstacle to social and economic development but part of the solution. It’s one of the drivers of sustainable development in Brazil and diverges from what was done in Europe 500 years ago, when the level of environmental awareness was different”, said Jean Paul Metzger, an ecologist at the University of São Paulo, who leads the signatories.

“Brazil conserves a great deal, protecting over 60% of its vegetation cover, and has strict legislation. It’s ranked 30th by the World Bank, behind Sweden and Finland, which protect approximately 70%. However, we must call attention to the fact that conservation isn’t bad,” said Professor Metzger.

Protection maintained

Brazilian law requires rural landowners to leave forest cover untouched on a percentage of their property: in the Amazon region as much as 80%; in other regions as little as 20%. But these protected areas shelter a third of the nation’s natural vegetation.

A bill that proposed to weaken or eliminate the Legal Reserve requirement went before the Brazilian Senate in 2019. Had it passed, it could have led to the loss altogether of 270 million hectares of native vegetation.

The bill has since been withdrawn, but a small army of scientists – including 371 researchers in 79 Brazilian laboratories, universities and institutions – have responded with a study that attempts to set a cash value to simply maintaining the natural capital of the wilderness.

Brazil is home to one of the world’s great tropical rainforests, and to one of the world’s richest centres of biodiversity. The global climate crisis is already taking its toll of the forest canopy in the form of drought and fire. But under new national leadership there have been fears that even more forest could be at risk.

“Preserving native vegetation isn’t an obstacle to social and economic development but part of the solution. It’s one of the drivers of sustainable development in Brazil”

The cash-value case for conservation has been made, and made repeatedly. Studies have confirmed that agribusiness monocultures – vast tracts devoted entirely to one crop and only one crop – are not sustainable: animal pollinators can make the best of the flowering season but then have no alternative sources of food for the rest of the year.

Other researchers have separately established that the loss of natural forest can be far more costly and economically damaging than anybody had expected; and that, conversely, conserved and undisturbed wilderness actually delivers wealth on a sustained basis for national and regional economies. But farmers concerned with immediate profits might not be so conscious of the long-term rewards of conservation.

“It’s an important paper because it presents sound information that can be used to refute the arguments of those who want to change the Brazilian Forest Code and do away with the legal reserve requirement”, said Carlos Joly of the Sao Paulo Research Foundation, and one of the signatories.

And his colleague Paulo Artaxo said: “Farmers sometimes take a short-term view that focuses on three or four years of personal profit, but the nation is left with enormous losses. This mindset should go. The paper makes that very clear.” – Climate News Network

Earth nears irreversible tipping points

Changes afoot now in at least nine areas could drastically alter the Earth’s climate. There’s no time left to act on these tipping points.

LONDON, 28 November, 2019 – On the eve of a global climate summit in Madrid, seven distinguished climate scientists have issued an urgent warning of approaching planetary tipping points: within a few years, they say, humankind could enter a state of potentially catastrophic climate change on a new “hothouse” Earth.

They warn that dramatic changes to planetary stability may already be happening in nine vulnerable ecosystems. As these changes happen, they could reinforce each other and at the same time amplify planetary temperature rise, commit the oceans to inexorable sea level rise of around 10 metres, and threaten the existence of human civilisations.

Their warning is issued in a commentary in the journal Nature. Their conclusions are not – and perhaps cannot be – confirmed by direct evidence or the consensus of other scientists. They present an opinion, not a set of facts that can be scrutinised and challenged or endorsed by their peers.

And the seven researchers recognise that although such changes are happening at speed, some of the consequences of those changes will follow more slowly. Their point is that the risks of irreversible change are too great not to act – and to act now.

Happening now

But the fact that they have chosen to issue such an alarm at all is a measure of the concern raised by the rapid retreat of the Arctic ice, the steady loss of the Greenland ice cap, the damage to the boreal forests, the thaw of the polar permafrost, the slowing of a great ocean current, the loss of tropical corals and the collapse of ice sheets in East and West Antarctica.

Each of these happenings – and many more – was identified more than a decade ago as a potential “tipping point”: an irreversible change that would amplify global heating and trigger a cascade of other climate changes.

“Now we see evidence that over half of them have been activated,” said Tim Lenton of the University of Exeter, UK. “The growing threat of rapid, irreversible changes means it is no longer responsible to wait and see.”

“The stability and resilience of our planet is in peril. International action – not just words – must reflect this”

The idea of a climate tipping point – a threshold beyond which dramatic climate change would be irreversible – is an old one. Two decades ago the Intergovernmental Panel on Climate Change examined the idea and proposed that, were the planet to warm by 5°C above the long-term average for most of human history, then it could tip into a new climate regime.

But in the last few decades, carbon dioxide concentrations in the atmosphere have gone from around 280 parts per million to more than 400 ppm, and global average temperatures have risen by more than 1°C. And the rate of change, driven by profligate use of fossil fuels that deposit greenhouse gases into the atmosphere, has been alarming.

“It is not only human pressures on Earth that continue rising to unprecedented levels. It is also that, as science advances, we must admit that we have underestimated the risks of unleashing irreversible changes, where the planet self-amplifies global warming. This is what we are seeing already at 1°C global warming,” said Johan Rockström, who directs the Potsdam Institute for Climate Impact Research in Germany, and who is another signatory.

“Scientifically, this provides strong evidence for declaring a state of planetary emergency, to unleash world action that accelerates the path towards a world that can continue evolving on a stable planet.”

Inadequate pledges

In 2015, at a climate summit in Paris, 195 nations promised to contain planetary heating to “well below” 2°C, and ideally to 1.5°C, by 2100. But the Nature signatories point at that even if the pledges those nations made are implemented – a “big if”, they warn – then they will ensure only that the world is committed to at least 3°C warming.

The scientists believe there is still time to act – but their dangerous tipping points are now dangerously close.

The arguments go like this. In West Antarctica, ice may already be retreating beyond the “grounding line” where ice, ocean and bedrock meet. If so, then the rest of the West Antarctic ice sheet could collapse, and sea levels could rise by three metres.

New evidence suggests the East Antarctic ice sheet could be similarly unstable, and precipitate further sea level rise of up to four metres. Hundreds of millions are already at risk from coastal flooding.

Timescale controlled

The Greenland ice sheet is melting at an accelerating rate, and once past a critical threshold could lose enough water to raise sea levels by seven metres. Even a 1.5°C warming might condemn Greenland to irreversible melting – and on present form the world could warm by 1.5°C by 2030.

“Thus we might have already committed future generations to living with sea level rises of around 10m over thousands of years. But the timescale is still under our control,” the authors warn.

They also warn that a “staggering 99% of tropical corals” could be lost if the planet heats by even 2°C – at a profound cost to both marine sea life and human economies.

They say 17% of the Amazon rainforest has been lost since 1970: a loss of somewhere between 20% and 40% could tip the entire rainforest into a destabilised state, increasingly at risk from drought and fire.

Risks multiply

In the boreal forests of northern Asia, Europe and Canada, insect outbreaks, fire and dieback could turn some regions into sources of more carbon, rather than sinks that soak up the extra carbon dioxide.

Permafrost thaw could release ever-greater volumes of stored methane, a greenhouse gas 30 times more potent, over a century, than carbon dioxide, and so on. The dangers multiply, and each one amplifies planetary heating.

“If damaging tipping cascades can occur and a global tipping point cannot be ruled out, then this is an existential threat to civilisation,” the authors warn.

“The stability and resilience of our planet is in peril. International action – not just words – must reflect this.” – Climate News Network

Changes afoot now in at least nine areas could drastically alter the Earth’s climate. There’s no time left to act on these tipping points.

LONDON, 28 November, 2019 – On the eve of a global climate summit in Madrid, seven distinguished climate scientists have issued an urgent warning of approaching planetary tipping points: within a few years, they say, humankind could enter a state of potentially catastrophic climate change on a new “hothouse” Earth.

They warn that dramatic changes to planetary stability may already be happening in nine vulnerable ecosystems. As these changes happen, they could reinforce each other and at the same time amplify planetary temperature rise, commit the oceans to inexorable sea level rise of around 10 metres, and threaten the existence of human civilisations.

Their warning is issued in a commentary in the journal Nature. Their conclusions are not – and perhaps cannot be – confirmed by direct evidence or the consensus of other scientists. They present an opinion, not a set of facts that can be scrutinised and challenged or endorsed by their peers.

And the seven researchers recognise that although such changes are happening at speed, some of the consequences of those changes will follow more slowly. Their point is that the risks of irreversible change are too great not to act – and to act now.

Happening now

But the fact that they have chosen to issue such an alarm at all is a measure of the concern raised by the rapid retreat of the Arctic ice, the steady loss of the Greenland ice cap, the damage to the boreal forests, the thaw of the polar permafrost, the slowing of a great ocean current, the loss of tropical corals and the collapse of ice sheets in East and West Antarctica.

Each of these happenings – and many more – was identified more than a decade ago as a potential “tipping point”: an irreversible change that would amplify global heating and trigger a cascade of other climate changes.

“Now we see evidence that over half of them have been activated,” said Tim Lenton of the University of Exeter, UK. “The growing threat of rapid, irreversible changes means it is no longer responsible to wait and see.”

“The stability and resilience of our planet is in peril. International action – not just words – must reflect this”

The idea of a climate tipping point – a threshold beyond which dramatic climate change would be irreversible – is an old one. Two decades ago the Intergovernmental Panel on Climate Change examined the idea and proposed that, were the planet to warm by 5°C above the long-term average for most of human history, then it could tip into a new climate regime.

But in the last few decades, carbon dioxide concentrations in the atmosphere have gone from around 280 parts per million to more than 400 ppm, and global average temperatures have risen by more than 1°C. And the rate of change, driven by profligate use of fossil fuels that deposit greenhouse gases into the atmosphere, has been alarming.

“It is not only human pressures on Earth that continue rising to unprecedented levels. It is also that, as science advances, we must admit that we have underestimated the risks of unleashing irreversible changes, where the planet self-amplifies global warming. This is what we are seeing already at 1°C global warming,” said Johan Rockström, who directs the Potsdam Institute for Climate Impact Research in Germany, and who is another signatory.

“Scientifically, this provides strong evidence for declaring a state of planetary emergency, to unleash world action that accelerates the path towards a world that can continue evolving on a stable planet.”

Inadequate pledges

In 2015, at a climate summit in Paris, 195 nations promised to contain planetary heating to “well below” 2°C, and ideally to 1.5°C, by 2100. But the Nature signatories point at that even if the pledges those nations made are implemented – a “big if”, they warn – then they will ensure only that the world is committed to at least 3°C warming.

The scientists believe there is still time to act – but their dangerous tipping points are now dangerously close.

The arguments go like this. In West Antarctica, ice may already be retreating beyond the “grounding line” where ice, ocean and bedrock meet. If so, then the rest of the West Antarctic ice sheet could collapse, and sea levels could rise by three metres.

New evidence suggests the East Antarctic ice sheet could be similarly unstable, and precipitate further sea level rise of up to four metres. Hundreds of millions are already at risk from coastal flooding.

Timescale controlled

The Greenland ice sheet is melting at an accelerating rate, and once past a critical threshold could lose enough water to raise sea levels by seven metres. Even a 1.5°C warming might condemn Greenland to irreversible melting – and on present form the world could warm by 1.5°C by 2030.

“Thus we might have already committed future generations to living with sea level rises of around 10m over thousands of years. But the timescale is still under our control,” the authors warn.

They also warn that a “staggering 99% of tropical corals” could be lost if the planet heats by even 2°C – at a profound cost to both marine sea life and human economies.

They say 17% of the Amazon rainforest has been lost since 1970: a loss of somewhere between 20% and 40% could tip the entire rainforest into a destabilised state, increasingly at risk from drought and fire.

Risks multiply

In the boreal forests of northern Asia, Europe and Canada, insect outbreaks, fire and dieback could turn some regions into sources of more carbon, rather than sinks that soak up the extra carbon dioxide.

Permafrost thaw could release ever-greater volumes of stored methane, a greenhouse gas 30 times more potent, over a century, than carbon dioxide, and so on. The dangers multiply, and each one amplifies planetary heating.

“If damaging tipping cascades can occur and a global tipping point cannot be ruled out, then this is an existential threat to civilisation,” the authors warn.

“The stability and resilience of our planet is in peril. International action – not just words – must reflect this.” – Climate News Network