Tag Archives: Glaciers

Antarctic depths warm far beyond oceanic average

Heat from factories and car exhausts must go somewhere. A surprising amount is now sunk in the remote Antarctic depths.

LONDON, 28 October, 2020 − Thanks to global heating, a vital part of the Southern Ocean is warming at a rate five times faster than the average for the Blue Planet as a whole, in the far Antarctic depths: 2000 metres or more below the surface of the Weddell Sea.

It is happening because at that depth the Weddell Sea has absorbed five times as much atmospheric heat − fuelled by greenhouse gas emissions from human fossil fuel combustion − as the average for the rest of the ocean. But what happens out of sight and far below the surface may not stay invisible. The Weddell Sea is where vast volumes of water circulate.

The fear is that such dramatic warming at depth could end up weakening a powerful current that encircles Antarctica, according to a new study in the Journal of Climate.

The evidence comes from 30 years of temperature and salinity samples, taken at the same spot and through the entire water column, with exquisite accuracy, by scientists aboard the German research icebreaker Polarstern.

“Our time series confirms the pivotal role of the Southern Ocean and especially the Weddell Sea in terms of storing heat in the depths of the world’s oceans”

“Our data shows a clear division in the water column of the Weddell Sea. While the water in the upper 700 metres has hardly warmed at all, in the deeper regions we’re seeing a consistent temperature rise of 0.0021 to 0.0024 degrees Celsius per year,” said Volker Strass, of the Alfred Wegener Institute in Bremerhaven in Germany.

“Since the ocean has roughly 1,000 times the heat capacity of the atmosphere, these numbers represent an enormous scale of heat absorption. By using the temperature rise to calculate the warming rate in watts per square metre, you can see that over the past 30 years, at depths of over 2,000 metres, the Weddell Sea has absorbed five times as much heat as the rest of the ocean on average.”

The global ocean is the great absorber of atmospheric shock. The deep blue sea has so far absorbed more than nine-tenths of the heat trapped by greenhouse gas emissions in the atmosphere.

The Weddell Sea begins at the extreme south of the Atlantic Ocean: it is roughly 10 times the size of Europe’s North Sea. Here tremendous volumes of water cool down. As sea ice forms on the surface the remaining waters become more salty, and because they have become colder, and denser, sink to the bottom, to spread at depth to drive deep sea flow into the oceans.

Ocean circulation risk

This act of overturning − the sinking of surface waters for thousands of metres into the Antarctic depths − is part of the machinery of ocean circulation that drives and modifies the world’s weather systems, and the climate.

The problem is that if the bottom waters are warming − and are therefore less dense − then this could weaken or stall the mechanism for ocean circulation. In the past 30 years the prevailing winds have shifted and intensified, and the flow speed of ocean water has increased to deliver more heat to the Weddell Sea with each decade.

Warming ocean waters have already been implicated in the loss of sea ice  cover that normally slows the flow of Antarctica’s continental glaciers. And warming in the Arctic has already triggered worries about the future of the “Atlantic Conveyer,” that enormous circulation of water that distributes heat from the Equator to the Poles and keeps northern Europe much warmer than its latitudes would dictate.

“Our time series confirms the pivotal role of the Southern Ocean and especially the Weddell Sea in terms of storing heat in the depths of the world’s oceans,” said Dr Strass. − Climate News Network

Heat from factories and car exhausts must go somewhere. A surprising amount is now sunk in the remote Antarctic depths.

LONDON, 28 October, 2020 − Thanks to global heating, a vital part of the Southern Ocean is warming at a rate five times faster than the average for the Blue Planet as a whole, in the far Antarctic depths: 2000 metres or more below the surface of the Weddell Sea.

It is happening because at that depth the Weddell Sea has absorbed five times as much atmospheric heat − fuelled by greenhouse gas emissions from human fossil fuel combustion − as the average for the rest of the ocean. But what happens out of sight and far below the surface may not stay invisible. The Weddell Sea is where vast volumes of water circulate.

The fear is that such dramatic warming at depth could end up weakening a powerful current that encircles Antarctica, according to a new study in the Journal of Climate.

The evidence comes from 30 years of temperature and salinity samples, taken at the same spot and through the entire water column, with exquisite accuracy, by scientists aboard the German research icebreaker Polarstern.

“Our time series confirms the pivotal role of the Southern Ocean and especially the Weddell Sea in terms of storing heat in the depths of the world’s oceans”

“Our data shows a clear division in the water column of the Weddell Sea. While the water in the upper 700 metres has hardly warmed at all, in the deeper regions we’re seeing a consistent temperature rise of 0.0021 to 0.0024 degrees Celsius per year,” said Volker Strass, of the Alfred Wegener Institute in Bremerhaven in Germany.

“Since the ocean has roughly 1,000 times the heat capacity of the atmosphere, these numbers represent an enormous scale of heat absorption. By using the temperature rise to calculate the warming rate in watts per square metre, you can see that over the past 30 years, at depths of over 2,000 metres, the Weddell Sea has absorbed five times as much heat as the rest of the ocean on average.”

The global ocean is the great absorber of atmospheric shock. The deep blue sea has so far absorbed more than nine-tenths of the heat trapped by greenhouse gas emissions in the atmosphere.

The Weddell Sea begins at the extreme south of the Atlantic Ocean: it is roughly 10 times the size of Europe’s North Sea. Here tremendous volumes of water cool down. As sea ice forms on the surface the remaining waters become more salty, and because they have become colder, and denser, sink to the bottom, to spread at depth to drive deep sea flow into the oceans.

Ocean circulation risk

This act of overturning − the sinking of surface waters for thousands of metres into the Antarctic depths − is part of the machinery of ocean circulation that drives and modifies the world’s weather systems, and the climate.

The problem is that if the bottom waters are warming − and are therefore less dense − then this could weaken or stall the mechanism for ocean circulation. In the past 30 years the prevailing winds have shifted and intensified, and the flow speed of ocean water has increased to deliver more heat to the Weddell Sea with each decade.

Warming ocean waters have already been implicated in the loss of sea ice  cover that normally slows the flow of Antarctica’s continental glaciers. And warming in the Arctic has already triggered worries about the future of the “Atlantic Conveyer,” that enormous circulation of water that distributes heat from the Equator to the Poles and keeps northern Europe much warmer than its latitudes would dictate.

“Our time series confirms the pivotal role of the Southern Ocean and especially the Weddell Sea in terms of storing heat in the depths of the world’s oceans,” said Dr Strass. − Climate News Network

China’s climate lead offers the planet new hope

Beijing’s plan to cut greenhouse gases could mean a global expansion of green industries following China’s climate lead.

LONDON, 19 October, 2020 – Whatever mixture of motives lies behind the announcement by President Xi Jinping that his country’s carbon dioxide emissions will peak before 2030, resulting in carbon neutrality before 2060, China’s climate lead offers the prospect of a new era in world affairs.

It alters the face of international negotiations to tackle the climate crisis and boosts hopes that catastrophic global heating can still be avoided.

It is not quite a month since the president took everyone by surprise by making the announcement at the United Nations. Cynics immediately began to question his motives.

Was he trying to corner the vast market in renewables, was he trying to upstage climate-denying and coal-loving President Trump, was he trying to divert attention from internal human rights issues and Hong Kong, or from accusations against China over the Covid crisis? Was he trying re-cast himself as a world leader on environmental matters?

Few seemed generous enough to accept that President Xi was making the announcement because he was genuinely concerned about the effects of climate change on China and the rest of the planet.

Either way, the President’s new targets were certainly a remarkable turnaround. Although there have been more positive statements recently, for more than a decade at successive climate talks China, along with the rest of the developing world, regarded climate change as the developed nations’ problem.

“China should strictly control coal consumption and the expansion of coal-fired power capacity in the next five years, aiming to cap carbon emissions from coal sectors by 2025”

The old industrial countries of the EU, the US and Japan had caused global heating by burning fossil fuels, they argued, so it was up to them to solve the crisis. The immediate job for the developing world’s leaders was to raise their citizens’ living standards, and to worry about their domestic carbon emissions later.

But this was never the whole story. Chinese scientists had long pointed out to its leaders that the country’s future was as bleak as any other nation’s in the world if climate change was not controlled – and quickly.

The major rivers that feed Chinese agriculture will dry up as the glaciers on the Himalayas and the Tibetan plateau disappear; typhoons will regularly threaten the populous south; and the deserts of the north will grow.

And more recently fast-accelerating sea level rise has begun to threaten the economic powerhouse of Shanghai and much of the low-lying coast with inundation.

In addition, since the Beijing Olympics in 2008 it has been clear that air pollution from coal-burning and traffic fumes is a serious economic and health issue in China, while some drastic measures have succeeded in improving air quality.

On 12 October 18 Chinese think tanks combined to put some flesh on the bare bones of President Xi’s bold announcement. In a report published by the Institute of Climate Change and Sustainable Development at Tsinghua University, Beijing, they said immediate carbon cuts were required to keep temperature increases within 1.5°C by 2050.

Globally significant

Reuters news agency reported that a seminar held in Beijing to launch the Institute ’s report was attended by China’s top officials responsible for shaping the country’s energy policy.

One of the report’s contributors, He Jiankun, vice-director of the National Expert Committee on Climate Change, told the meeting: “China should strictly control coal consumption and the expansion of coal-fired power capacity in the next five years, aiming to cap carbon emissions from coal sectors by 2025 and even realise negative growth.

“China is still expected to see the growth of natural gas consumption in 2026-2030, so the growth of carbon emissions from gas use should be offset by the reduction from the coal sector.”

The report also called for China to cut its carbon intensity – the amount of carbon dioxide emissions per GDP unit – by 65% by 2030 from 2015 levels, and to raise non-fossil fuel consumption to 25% by 2030.

This is way above anything that the Chinese government has committed to in the annual UN climate talks and would mean a drastic change in direction, since new coal power stations are still being constructed in large numbers to meet an ever-growing energy demand.

Whatever the motives behind these reduction targets, they matter hugely to the rest of the world. China is currently the world’s largest carbon emitter, with about 29% of the total. This is mainly due to massive coal burning for electricity and for major heavy industries like steel-making, which have moved there from Europe and the US. Switching away from coal would make an immediate difference.

Eye on exports

While critics, particularly climate deniers and right-wing think tanks in the US and Europe, constantly remind the world of Chinese coal-burning habits, they often neglect to mention that the country is a world leader in on-shore wind energy and solar power.

China is also aiming to soon have the largest off-shore wind market, overtaking the United Kingdom.

This might be the key to the President’s thinking. China has a massive domestic demand for renewables, but with wind and solar being the two fastest-growing industries in the world the export market is a great prize.

With President Trump firmly stuck in the fossil fuel age, China has an opportunity to become the lead provider of the technology that many countries in the world need to meet their climate targets.

Depending on who wins the US election on 3 November, President Xi may consolidate his renewables lead at leisure, or be in a race against the Democrat contender, Joe Biden, who has pledged to turn America from a climate laggard to a world leader.

If Biden does win he may find President Xi is already a lap ahead, and hard to overtake. – Climate News Network

Beijing’s plan to cut greenhouse gases could mean a global expansion of green industries following China’s climate lead.

LONDON, 19 October, 2020 – Whatever mixture of motives lies behind the announcement by President Xi Jinping that his country’s carbon dioxide emissions will peak before 2030, resulting in carbon neutrality before 2060, China’s climate lead offers the prospect of a new era in world affairs.

It alters the face of international negotiations to tackle the climate crisis and boosts hopes that catastrophic global heating can still be avoided.

It is not quite a month since the president took everyone by surprise by making the announcement at the United Nations. Cynics immediately began to question his motives.

Was he trying to corner the vast market in renewables, was he trying to upstage climate-denying and coal-loving President Trump, was he trying to divert attention from internal human rights issues and Hong Kong, or from accusations against China over the Covid crisis? Was he trying re-cast himself as a world leader on environmental matters?

Few seemed generous enough to accept that President Xi was making the announcement because he was genuinely concerned about the effects of climate change on China and the rest of the planet.

Either way, the President’s new targets were certainly a remarkable turnaround. Although there have been more positive statements recently, for more than a decade at successive climate talks China, along with the rest of the developing world, regarded climate change as the developed nations’ problem.

“China should strictly control coal consumption and the expansion of coal-fired power capacity in the next five years, aiming to cap carbon emissions from coal sectors by 2025”

The old industrial countries of the EU, the US and Japan had caused global heating by burning fossil fuels, they argued, so it was up to them to solve the crisis. The immediate job for the developing world’s leaders was to raise their citizens’ living standards, and to worry about their domestic carbon emissions later.

But this was never the whole story. Chinese scientists had long pointed out to its leaders that the country’s future was as bleak as any other nation’s in the world if climate change was not controlled – and quickly.

The major rivers that feed Chinese agriculture will dry up as the glaciers on the Himalayas and the Tibetan plateau disappear; typhoons will regularly threaten the populous south; and the deserts of the north will grow.

And more recently fast-accelerating sea level rise has begun to threaten the economic powerhouse of Shanghai and much of the low-lying coast with inundation.

In addition, since the Beijing Olympics in 2008 it has been clear that air pollution from coal-burning and traffic fumes is a serious economic and health issue in China, while some drastic measures have succeeded in improving air quality.

On 12 October 18 Chinese think tanks combined to put some flesh on the bare bones of President Xi’s bold announcement. In a report published by the Institute of Climate Change and Sustainable Development at Tsinghua University, Beijing, they said immediate carbon cuts were required to keep temperature increases within 1.5°C by 2050.

Globally significant

Reuters news agency reported that a seminar held in Beijing to launch the Institute ’s report was attended by China’s top officials responsible for shaping the country’s energy policy.

One of the report’s contributors, He Jiankun, vice-director of the National Expert Committee on Climate Change, told the meeting: “China should strictly control coal consumption and the expansion of coal-fired power capacity in the next five years, aiming to cap carbon emissions from coal sectors by 2025 and even realise negative growth.

“China is still expected to see the growth of natural gas consumption in 2026-2030, so the growth of carbon emissions from gas use should be offset by the reduction from the coal sector.”

The report also called for China to cut its carbon intensity – the amount of carbon dioxide emissions per GDP unit – by 65% by 2030 from 2015 levels, and to raise non-fossil fuel consumption to 25% by 2030.

This is way above anything that the Chinese government has committed to in the annual UN climate talks and would mean a drastic change in direction, since new coal power stations are still being constructed in large numbers to meet an ever-growing energy demand.

Whatever the motives behind these reduction targets, they matter hugely to the rest of the world. China is currently the world’s largest carbon emitter, with about 29% of the total. This is mainly due to massive coal burning for electricity and for major heavy industries like steel-making, which have moved there from Europe and the US. Switching away from coal would make an immediate difference.

Eye on exports

While critics, particularly climate deniers and right-wing think tanks in the US and Europe, constantly remind the world of Chinese coal-burning habits, they often neglect to mention that the country is a world leader in on-shore wind energy and solar power.

China is also aiming to soon have the largest off-shore wind market, overtaking the United Kingdom.

This might be the key to the President’s thinking. China has a massive domestic demand for renewables, but with wind and solar being the two fastest-growing industries in the world the export market is a great prize.

With President Trump firmly stuck in the fossil fuel age, China has an opportunity to become the lead provider of the technology that many countries in the world need to meet their climate targets.

Depending on who wins the US election on 3 November, President Xi may consolidate his renewables lead at leisure, or be in a race against the Democrat contender, Joe Biden, who has pledged to turn America from a climate laggard to a world leader.

If Biden does win he may find President Xi is already a lap ahead, and hard to overtake. – Climate News Network

Antarctica’s ice loss could soon be irreversible

Global heating means the southern ice will melt. Antarctica’s ice loss could then be permanent, drowning many great cities.

LONDON, 2 October, 2020 – The greatest mass of ice on the planet is growing steadily more unstable, and that means Antarctica’s ice loss may before long be inexorable.

New studies show that right now, just one degree of warming must mean an eventual sea level rise of 1.3 metres, simply from the flow of melting ice from the continent of Antarctica.

If the annual average temperature of the planet goes beyond 2°C, then the Antarctic melting rate will double. And when global heating really steps up to 6°C or beyond, melting accelerates to the almost unimaginable level of 10 metres for every single degree rise in planetary average temperatures.

And, the researchers say, there is no way back. Even if the world’s nations stick to a promise made in Paris in 2015, to keep global heating to “well below” 2°C by the end of the century, the losses of the southern polar ice sheet cannot be restored: the process of melting, once triggered by global temperature rise, becomes inexorable.

European and US researchers report in the journal Nature that they worked through ice core records of long-ago change in Antarctica and employed a million hours of computer simulation time to build up a reliable picture of change on the Antarctic continent, in response to ever-higher planetary average temperatures, driven by ever more profligate use of fossil fuels to generate ever-higher atmospheric ratios of greenhouse gases.

Their word for the state they wanted to study is hysteresis: this can be interpreted as the way altered conditions might commit a state to further change.

“If we give up the Paris Agreement, we give up Hamburg, Tokyo and New York”

The planet’s climate has oscillated many times over many millions of years. What this climate shift does to the polar regions can literally change the map of the planet. Antarctica is an enormous continent, the size of the US, Mexico and India together, and the ice it bears would, if it all were to melt, raise global sea levels by 58 metres.

“Antarctica holds more than half of Earth’s fresh water, frozen in a vast ice-sheet which is nearly five kilometres thick. As the surrounding ocean water and atmosphere warm due to human greenhouse gas emissions, the white cap on the South Pole loses mass and eventually becomes unstable,” said Ricarda Winkelmann, of the Potsdam Institute for Climate Impact Research.

“Because of its sheer magnitude, Antarctica’s potential for sea level contribution is enormous. We find that already at two degrees of warming, melting and the accelerated ice flow into the ocean will, eventually, entail 2.5 metres of global sea level rise just from Antarctica alone. At four degrees, it will be 6.5 metres and at six degrees almost 12 metres, if these temperature levels would be sustained long enough.”

That loss of ice would be slow – it would take many thousands of years – but the point the researchers make is that the continent may already be nearing a tipping point, after which the slide towards ever-higher sea levels would be unstoppable.

Since the great ice sheets of Greenland and Antarctica are part of the planetary cooling system – their whiteness reflects solar radiation back into space, so that the ice becomes its own insulation – their loss would inevitably trigger the process of further and faster warming.

Scientists from all nations have been warning for more than a decade that the continent is losing its protective screen of seaborne shelf ice, which in turn would make glacier flow towards the sea ever faster, and that the rate of loss of ice has begun to accelerate.

No going back

“In the end, it is our burning of coal and oil that determines ongoing and future greenhouse gas emissions and, therefore, if and when critical temperature thresholds in Antarctica are crossed.

“And even if the ice loss happens on long time scales, the respective carbon dioxide levels can already be reached in the near future,” said Professor Winkelmann.

“We decide now whether we manage to halt the warming. So Antarctica’s fate really lies in our hands – and with it that of our cities and cultural sites across the globe, from Rio de Janeiro’s Copacabana to Sydney’s Opera House. Thus this study really is another exclamation mark behind the importance of the Paris Climate Accord: Keep global warming below two degrees.”

And her Potsdam co-author Anders Levermann reinforced the argument. “Our simulations show that once it’s melted, it does not regrow to its initial state even if temperatures eventually sank again.

“Indeed, temperatures would have to go back to pre-industrial levels to allow its full recovery – a highly unlikely scenario. In other words: what we lose of Antarctica now is lost forever.”

And he warned: “If we give up the Paris Agreement, we give up Hamburg, Tokyo and New York.” – Climate News Network

Global heating means the southern ice will melt. Antarctica’s ice loss could then be permanent, drowning many great cities.

LONDON, 2 October, 2020 – The greatest mass of ice on the planet is growing steadily more unstable, and that means Antarctica’s ice loss may before long be inexorable.

New studies show that right now, just one degree of warming must mean an eventual sea level rise of 1.3 metres, simply from the flow of melting ice from the continent of Antarctica.

If the annual average temperature of the planet goes beyond 2°C, then the Antarctic melting rate will double. And when global heating really steps up to 6°C or beyond, melting accelerates to the almost unimaginable level of 10 metres for every single degree rise in planetary average temperatures.

And, the researchers say, there is no way back. Even if the world’s nations stick to a promise made in Paris in 2015, to keep global heating to “well below” 2°C by the end of the century, the losses of the southern polar ice sheet cannot be restored: the process of melting, once triggered by global temperature rise, becomes inexorable.

European and US researchers report in the journal Nature that they worked through ice core records of long-ago change in Antarctica and employed a million hours of computer simulation time to build up a reliable picture of change on the Antarctic continent, in response to ever-higher planetary average temperatures, driven by ever more profligate use of fossil fuels to generate ever-higher atmospheric ratios of greenhouse gases.

Their word for the state they wanted to study is hysteresis: this can be interpreted as the way altered conditions might commit a state to further change.

“If we give up the Paris Agreement, we give up Hamburg, Tokyo and New York”

The planet’s climate has oscillated many times over many millions of years. What this climate shift does to the polar regions can literally change the map of the planet. Antarctica is an enormous continent, the size of the US, Mexico and India together, and the ice it bears would, if it all were to melt, raise global sea levels by 58 metres.

“Antarctica holds more than half of Earth’s fresh water, frozen in a vast ice-sheet which is nearly five kilometres thick. As the surrounding ocean water and atmosphere warm due to human greenhouse gas emissions, the white cap on the South Pole loses mass and eventually becomes unstable,” said Ricarda Winkelmann, of the Potsdam Institute for Climate Impact Research.

“Because of its sheer magnitude, Antarctica’s potential for sea level contribution is enormous. We find that already at two degrees of warming, melting and the accelerated ice flow into the ocean will, eventually, entail 2.5 metres of global sea level rise just from Antarctica alone. At four degrees, it will be 6.5 metres and at six degrees almost 12 metres, if these temperature levels would be sustained long enough.”

That loss of ice would be slow – it would take many thousands of years – but the point the researchers make is that the continent may already be nearing a tipping point, after which the slide towards ever-higher sea levels would be unstoppable.

Since the great ice sheets of Greenland and Antarctica are part of the planetary cooling system – their whiteness reflects solar radiation back into space, so that the ice becomes its own insulation – their loss would inevitably trigger the process of further and faster warming.

Scientists from all nations have been warning for more than a decade that the continent is losing its protective screen of seaborne shelf ice, which in turn would make glacier flow towards the sea ever faster, and that the rate of loss of ice has begun to accelerate.

No going back

“In the end, it is our burning of coal and oil that determines ongoing and future greenhouse gas emissions and, therefore, if and when critical temperature thresholds in Antarctica are crossed.

“And even if the ice loss happens on long time scales, the respective carbon dioxide levels can already be reached in the near future,” said Professor Winkelmann.

“We decide now whether we manage to halt the warming. So Antarctica’s fate really lies in our hands – and with it that of our cities and cultural sites across the globe, from Rio de Janeiro’s Copacabana to Sydney’s Opera House. Thus this study really is another exclamation mark behind the importance of the Paris Climate Accord: Keep global warming below two degrees.”

And her Potsdam co-author Anders Levermann reinforced the argument. “Our simulations show that once it’s melted, it does not regrow to its initial state even if temperatures eventually sank again.

“Indeed, temperatures would have to go back to pre-industrial levels to allow its full recovery – a highly unlikely scenario. In other words: what we lose of Antarctica now is lost forever.”

And he warned: “If we give up the Paris Agreement, we give up Hamburg, Tokyo and New York.” – Climate News Network

Pandemic’s impacts are damaging climate research

Climate research is suffering permanent damage from some of the Covid-19 pandemic’s impacts, a UN report says.

LONDON, 9 September, 2020 − Whatever else the coronavirus onslaught is doing to humankind, some of the pandemic’s impacts are clear. It is making it harder for researchers to establish just what effect climate change is having on the planet.

A group of United Nations and other agencies is today launching a report, United in Science 2020, (webcast at 1600 hours New York time) which it calls “a high-level compilation of the latest climate science information”. It is being launched by the UN secretary-general, António Guterres, with a virtual link to his counterpart at the World Meteorological Organisation,  Petteri Taalas, in Geneva.

Much of what the report says will already be familiar, but its detailed finding that the pandemic is causing long-term damage to climate change monitoring is sobering.

Science advances by combining knowledge of the past with experience of the present and then combining them to forecast the probable future. That is how climate scientists have been able very recently to state that their earlier worst case scenario isn’t just an awful warning, but describes what is happening right now.

Several contenders have vied to be identified as the one who wrote: “You cannot manage what you cannot measure.” Which of them − if any − really did write that may not matter much. But it certainly matters for today’s researchers to know where the biosphere came from and where it is now if they are to have any idea where we shall all be in a few years.

Recalled to port

So it’s alarming that United in Science 2020, in its section on earth system observations, says: “The Covid-19 pandemic has produced significant impacts on the global observing systems, which in turn have affected the quality of forecasts and other weather, climate and ocean-related services.

“The reduction of aircraft-based observations by an average of 75% to 80% in March and April degraded the forecast skills of weather models. Since June, there has been only a slight recovery. Observations at manually-operated weather stations, especially in Africa and South America, have also been badly disrupted.”

In March this year, it says, nearly all oceanographic research vessels were recalled to home ports. Commercial ships have been unable to contribute vital ocean and weather observations, and ocean buoys and other systems could not be maintained.

Four “valuable” full-depth ocean surveys of variables such as carbon, temperature, salinity, and water alkalinity, completed only once every decade, have been cancelled. Surface carbon measurements from ships, which cast light on the evolution of greenhouse gases, also effectively stopped.

The impacts on climate change monitoring are long-term. They are likely to prevent or restrict measurement of glaciers and the thickness of permafrost, usually conducted at the end of the thawing period.

In an ominous warning the report notes that the overall disruption of observations will introduce gaps in the historical time series of Essential Climate Variables, vital for understanding what is happening to the planetary climate.

“The reduction of aircraft-based observations by an average of 75% to 80% in March and April degraded the forecast skills of weather models”

The report’s authors are also concerned about climate and water, where they expect the pandemic’s impacts to intensify existing problems. By 2050, they say, the number of people at risk of floods will increase from 1.2 billion now to 1.6 bn.

In the early to mid-2010s, 1.9 bn people, or 27% of the global population, lived in potential severely water-scarce areas. In 2050, this number will increase to between 2.7 and 3.2 bn people.

It is estimated that central Europe and the Caucasus have already reached peak water, and that the Tibetan Plateau region will do so between 2030 and 2050.

Runoff from snow cover, permafrost and glaciers in this region provides up to 45% of the total river flow, so a decrease would affect water availability for 1.7 bn people.

United in Science 2020 also says the world is a very long way from living up to its promises, with the targets of the Paris Agreement on climate change nowhere near being met.

The UN’s Emissions Gap Report 2019 compares “where we are likely to be and where we need to be” on cutting emissions of greenhouse gases (GHGs). The annual series of Gap Reports use gigatonnes (Gt) as units of measurement: one gigatonne is a billion metric tons.

Record emissions

Another frequent formula is GtCO2e, an abbreviation for “gigatonnes of equivalent carbon dioxide”. That’s a simplified way to put emissions of various GHGs on a common footing by expressing them in terms of the amount of carbon dioxide that would have the same global warming effect.

The 2019 Report says GHG emissions reached a record high of 55.3 GtCO2e in 2018. It continues: “There is no sign of GHG emissions peaking in the next few years; every year of postponed peaking means that deeper and faster cuts will be required.

“By 2030, emissions would need to be 25% and 55% lower than in 2018 to put the world on the least-cost pathway to limiting global warming to below 2 ̊C and 1.5°C respectively” [the two Paris Agreement targets].

The Gap in 2030 is estimated at 12-15 gigatonnes if the world is to limit global warming to below 2 °C. For the 1.5 °C goal, it is estimated at 29-32 Gt, roughly equivalent to the combined emissions of the world’s six largest emitters.

That’s an awful lot of GHGs which, as things stand, are going to be adding their heat to a torrid world a decade from now. − Climate News Network

Climate research is suffering permanent damage from some of the Covid-19 pandemic’s impacts, a UN report says.

LONDON, 9 September, 2020 − Whatever else the coronavirus onslaught is doing to humankind, some of the pandemic’s impacts are clear. It is making it harder for researchers to establish just what effect climate change is having on the planet.

A group of United Nations and other agencies is today launching a report, United in Science 2020, (webcast at 1600 hours New York time) which it calls “a high-level compilation of the latest climate science information”. It is being launched by the UN secretary-general, António Guterres, with a virtual link to his counterpart at the World Meteorological Organisation,  Petteri Taalas, in Geneva.

Much of what the report says will already be familiar, but its detailed finding that the pandemic is causing long-term damage to climate change monitoring is sobering.

Science advances by combining knowledge of the past with experience of the present and then combining them to forecast the probable future. That is how climate scientists have been able very recently to state that their earlier worst case scenario isn’t just an awful warning, but describes what is happening right now.

Several contenders have vied to be identified as the one who wrote: “You cannot manage what you cannot measure.” Which of them − if any − really did write that may not matter much. But it certainly matters for today’s researchers to know where the biosphere came from and where it is now if they are to have any idea where we shall all be in a few years.

Recalled to port

So it’s alarming that United in Science 2020, in its section on earth system observations, says: “The Covid-19 pandemic has produced significant impacts on the global observing systems, which in turn have affected the quality of forecasts and other weather, climate and ocean-related services.

“The reduction of aircraft-based observations by an average of 75% to 80% in March and April degraded the forecast skills of weather models. Since June, there has been only a slight recovery. Observations at manually-operated weather stations, especially in Africa and South America, have also been badly disrupted.”

In March this year, it says, nearly all oceanographic research vessels were recalled to home ports. Commercial ships have been unable to contribute vital ocean and weather observations, and ocean buoys and other systems could not be maintained.

Four “valuable” full-depth ocean surveys of variables such as carbon, temperature, salinity, and water alkalinity, completed only once every decade, have been cancelled. Surface carbon measurements from ships, which cast light on the evolution of greenhouse gases, also effectively stopped.

The impacts on climate change monitoring are long-term. They are likely to prevent or restrict measurement of glaciers and the thickness of permafrost, usually conducted at the end of the thawing period.

In an ominous warning the report notes that the overall disruption of observations will introduce gaps in the historical time series of Essential Climate Variables, vital for understanding what is happening to the planetary climate.

“The reduction of aircraft-based observations by an average of 75% to 80% in March and April degraded the forecast skills of weather models”

The report’s authors are also concerned about climate and water, where they expect the pandemic’s impacts to intensify existing problems. By 2050, they say, the number of people at risk of floods will increase from 1.2 billion now to 1.6 bn.

In the early to mid-2010s, 1.9 bn people, or 27% of the global population, lived in potential severely water-scarce areas. In 2050, this number will increase to between 2.7 and 3.2 bn people.

It is estimated that central Europe and the Caucasus have already reached peak water, and that the Tibetan Plateau region will do so between 2030 and 2050.

Runoff from snow cover, permafrost and glaciers in this region provides up to 45% of the total river flow, so a decrease would affect water availability for 1.7 bn people.

United in Science 2020 also says the world is a very long way from living up to its promises, with the targets of the Paris Agreement on climate change nowhere near being met.

The UN’s Emissions Gap Report 2019 compares “where we are likely to be and where we need to be” on cutting emissions of greenhouse gases (GHGs). The annual series of Gap Reports use gigatonnes (Gt) as units of measurement: one gigatonne is a billion metric tons.

Record emissions

Another frequent formula is GtCO2e, an abbreviation for “gigatonnes of equivalent carbon dioxide”. That’s a simplified way to put emissions of various GHGs on a common footing by expressing them in terms of the amount of carbon dioxide that would have the same global warming effect.

The 2019 Report says GHG emissions reached a record high of 55.3 GtCO2e in 2018. It continues: “There is no sign of GHG emissions peaking in the next few years; every year of postponed peaking means that deeper and faster cuts will be required.

“By 2030, emissions would need to be 25% and 55% lower than in 2018 to put the world on the least-cost pathway to limiting global warming to below 2 ̊C and 1.5°C respectively” [the two Paris Agreement targets].

The Gap in 2030 is estimated at 12-15 gigatonnes if the world is to limit global warming to below 2 °C. For the 1.5 °C goal, it is estimated at 29-32 Gt, roughly equivalent to the combined emissions of the world’s six largest emitters.

That’s an awful lot of GHGs which, as things stand, are going to be adding their heat to a torrid world a decade from now. − Climate News Network

In Arctic heat Greenland’s ice loss grows faster still

Greenland’s ice loss tipped a new record last year. This ominous milestone is just the latest in a run of alarming news.

LONDON, 24 August, 2020 – Its icecap is now smaller than at any time since measurements began: Greenland’s ice loss means it lost mass in 2019 at a record rate.

By the close of the year, thanks to high summer melt and low snowfall, the northern hemisphere’s biggest reservoir of ice had shed 532 billion tonnes into the sea – raising global sea levels by around 1.5mm in a year.

The previous record loss for Greenland was in 2012. In that year, the island lost 464 billion tonnes, according to studies of satellite data published by European scientists in the journal Communications Earth and Environment.

Greenland’s ice cap has been shrinking, if unsteadily, for many years. In 2017 and 2018, the losses continued, but only at around 100bn tonnes a year.

“After a two-year breather, the mass loss increased steeply and exceeded all annual losses since 1948, and probably for more than 100 years,” said Ingo Sasgen of the Alfred Wegener Institute in Bremerhaven, Germany, who led the study.

“There are increasingly frequent, stable high-pressure areas over the ice sheet, which promote the influx of warm air from the middle latitudes. We saw a similar pattern in the previous record year, 2012.”

“The ice sheet has lost ice every year for the past 20. If everyone’s alarm bells were not already ringing, they must be now”

He and colleagues made their calculations from data delivered by two Nasa satellites, GRACE and GRACE-FO, that measure changes in the surface gravity of the planet: a way of calculating the mass of water stored as ice, or in aquifers, and observing sea level change.

The finding is the latest in a succession of polar climate alarms. It follows closely on a warning from US scientists that ice loss from Greenland may  have reached the point of no return.

And it also follows a sober calculation of the alarming rate of planetary temperature rise in response to ever-higher use of fossil fuels that trigger ever-higher measures of greenhouse gases in the atmosphere.

And that in turn followed a warning that the entire Arctic was now warming so swiftly that the Arctic sea ice might be all but gone in the summer of 2035.

And that was only days after another research team, looking at the big picture of climate change, warned that the scenario climate forecasters liked to use as an example of their “worst case” was now a simple description of what was already happening.

“It is devastating that 2019 was another record year of ice loss. In 2012, it had been about 150 years since the ice sheet had experienced similar melt extent, and then a further 600-plus years back to find another similar event,” said Twila Moon, of the University of Colorado at Boulder, who was not involved in the research.

Damage off the scale

“We have now had record-breaking ice loss twice in less than 10 years, and the ice sheet has lost ice every year for the past 20. If everyone’s alarm bells were not already ringing, they must be now.”

The implications of continued loss of Greenland ice have been explored repeatedly: the run-off of fresh water from the ice cap to the sea is now so great that the North Atlantic is now “fresher” than at any time in the last 100 years.

And this change in water temperature and chemistry could – on the evidence of the distant past – possibly slow or switch off the circulation of the North Atlantic current, which for most of the history of human civilisation has kept the United Kingdom and north-western Europe from five to 10°C warmer than similar latitudes elsewhere.

“This tipping point in the climate system is one of the potential climate disasters facing us,” said Stuart Cunningham of the Scottish Association for Marine Science, commenting on the study.

“To transform the way we power, finance and run the world in the way we know we should is proving entirely beyond us,” said Chris Rapley, now a climate scientist at University College London, but once director of the British Antarctic Survey.

“Torpor, incompetence and indifference at the top may kill people in a health crisis, and torpedo the careers of young students in an education crisis; but the damage they are generating in the pipeline from climate change is on another scale.” – Climate News Network

Greenland’s ice loss tipped a new record last year. This ominous milestone is just the latest in a run of alarming news.

LONDON, 24 August, 2020 – Its icecap is now smaller than at any time since measurements began: Greenland’s ice loss means it lost mass in 2019 at a record rate.

By the close of the year, thanks to high summer melt and low snowfall, the northern hemisphere’s biggest reservoir of ice had shed 532 billion tonnes into the sea – raising global sea levels by around 1.5mm in a year.

The previous record loss for Greenland was in 2012. In that year, the island lost 464 billion tonnes, according to studies of satellite data published by European scientists in the journal Communications Earth and Environment.

Greenland’s ice cap has been shrinking, if unsteadily, for many years. In 2017 and 2018, the losses continued, but only at around 100bn tonnes a year.

“After a two-year breather, the mass loss increased steeply and exceeded all annual losses since 1948, and probably for more than 100 years,” said Ingo Sasgen of the Alfred Wegener Institute in Bremerhaven, Germany, who led the study.

“There are increasingly frequent, stable high-pressure areas over the ice sheet, which promote the influx of warm air from the middle latitudes. We saw a similar pattern in the previous record year, 2012.”

“The ice sheet has lost ice every year for the past 20. If everyone’s alarm bells were not already ringing, they must be now”

He and colleagues made their calculations from data delivered by two Nasa satellites, GRACE and GRACE-FO, that measure changes in the surface gravity of the planet: a way of calculating the mass of water stored as ice, or in aquifers, and observing sea level change.

The finding is the latest in a succession of polar climate alarms. It follows closely on a warning from US scientists that ice loss from Greenland may  have reached the point of no return.

And it also follows a sober calculation of the alarming rate of planetary temperature rise in response to ever-higher use of fossil fuels that trigger ever-higher measures of greenhouse gases in the atmosphere.

And that in turn followed a warning that the entire Arctic was now warming so swiftly that the Arctic sea ice might be all but gone in the summer of 2035.

And that was only days after another research team, looking at the big picture of climate change, warned that the scenario climate forecasters liked to use as an example of their “worst case” was now a simple description of what was already happening.

“It is devastating that 2019 was another record year of ice loss. In 2012, it had been about 150 years since the ice sheet had experienced similar melt extent, and then a further 600-plus years back to find another similar event,” said Twila Moon, of the University of Colorado at Boulder, who was not involved in the research.

Damage off the scale

“We have now had record-breaking ice loss twice in less than 10 years, and the ice sheet has lost ice every year for the past 20. If everyone’s alarm bells were not already ringing, they must be now.”

The implications of continued loss of Greenland ice have been explored repeatedly: the run-off of fresh water from the ice cap to the sea is now so great that the North Atlantic is now “fresher” than at any time in the last 100 years.

And this change in water temperature and chemistry could – on the evidence of the distant past – possibly slow or switch off the circulation of the North Atlantic current, which for most of the history of human civilisation has kept the United Kingdom and north-western Europe from five to 10°C warmer than similar latitudes elsewhere.

“This tipping point in the climate system is one of the potential climate disasters facing us,” said Stuart Cunningham of the Scottish Association for Marine Science, commenting on the study.

“To transform the way we power, finance and run the world in the way we know we should is proving entirely beyond us,” said Chris Rapley, now a climate scientist at University College London, but once director of the British Antarctic Survey.

“Torpor, incompetence and indifference at the top may kill people in a health crisis, and torpedo the careers of young students in an education crisis; but the damage they are generating in the pipeline from climate change is on another scale.” – Climate News Network

Greenland is losing more ice than it gains annually

The ice lost to the sea annually off Greenland is now more than the snow falling on the island. This is a tipping point.

LONDON, 18 August, 2020 – The loss of ice from Greenland may have reached the point of no return. The island’s glaciers have dwindled and retreated so much that annual snowfall can no longer replace the lost ice.

New studies confirm that between 1980 and the year 2000, the island – the biggest single store of ice in the northern hemisphere – lost on average 450 billion tonnes of ice each year from its glaciers. This is about what falls as snow and stays on the island’s surface each year.

And then 20 years ago the rate of melt – already speeding up – accelerated again. The glaciers are now spilling more than 500 billion tonnes of ice into the seas. But snowfall has not increased.

And US scientists warn, in the normally guarded language of science, of a “switch to a new dynamic state of sustained mass loss that would persist even under a decline in surface melt.”

“Glacier retreat has knocked the dynamics of the whole ice sheet into a constant state of loss”

The scientists base their new conclusions on a careful re-examination of 40 years of satellite observations to check the rates of snowfall and ice loss. “What we’ve found is that the ice that’s discharging into the ocean is far surpassing the snow that’s accumulating on the surface of the ice sheet,” said Michalea King of Ohio State University, who led the research. .

The news, in the journal Nature Communications Earth and Environment, is alarming but hardly surprising. In December researchers warned that – even to begin to arrest the melting of a store of ice big enough to raise global sea levels by up to seven metres the world would have to take immediate and drastic steps to halt global heating.

Researchers have found that surface melting is at a rate that has begun to make the glaciers more unstable. They have confirmed that the rate of melt is accelerating so swiftly that the bedrock beneath the weight of ice has begun to rise, while a range of other climate change triggers has begun to darken the ice cover in ways that can only increase the absorption of heat and step up the rate of melt.

The latest evidence is that the world has passed a tipping point of sorts: once such things happen, there is no way back.

Glaciers gather speed

All icecaps melt in summer, and all icecaps are drained by glaciers, rivers of ice that make slow progress to the sea. In a stable climate, annual precipitation and annual glacier calving remain more or less in balance, and the icecap functions as its own refrigerant. The whiteness of the ice reflects sunlight back into space and insulates itself against significant loss.

But as the air and oceans warm in response to ever higher levels of greenhouse gases pumped into the atmosphere as nations continue to burn ever more coal, oil and gas, the rates of melt became more dramatic and the glaciers began to flow ever faster: one of them was clocked at 45 metres a day.

The message of the latest research is that, even if somehow humans could immediately halt climate change, the ice likely to be lost as the glaciers reach the sea would still be greater than the accumulation of ice on the surface each winter.

“Glacier retreat has knocked the dynamics of the whole ice sheet into a constant state of loss,” said Ian Howat, a co-author at Ohio State University. “Even if the climate were to stay the same or get a little colder, the ice sheet would still be losing mass.” – Climate News Network

The ice lost to the sea annually off Greenland is now more than the snow falling on the island. This is a tipping point.

LONDON, 18 August, 2020 – The loss of ice from Greenland may have reached the point of no return. The island’s glaciers have dwindled and retreated so much that annual snowfall can no longer replace the lost ice.

New studies confirm that between 1980 and the year 2000, the island – the biggest single store of ice in the northern hemisphere – lost on average 450 billion tonnes of ice each year from its glaciers. This is about what falls as snow and stays on the island’s surface each year.

And then 20 years ago the rate of melt – already speeding up – accelerated again. The glaciers are now spilling more than 500 billion tonnes of ice into the seas. But snowfall has not increased.

And US scientists warn, in the normally guarded language of science, of a “switch to a new dynamic state of sustained mass loss that would persist even under a decline in surface melt.”

“Glacier retreat has knocked the dynamics of the whole ice sheet into a constant state of loss”

The scientists base their new conclusions on a careful re-examination of 40 years of satellite observations to check the rates of snowfall and ice loss. “What we’ve found is that the ice that’s discharging into the ocean is far surpassing the snow that’s accumulating on the surface of the ice sheet,” said Michalea King of Ohio State University, who led the research. .

The news, in the journal Nature Communications Earth and Environment, is alarming but hardly surprising. In December researchers warned that – even to begin to arrest the melting of a store of ice big enough to raise global sea levels by up to seven metres the world would have to take immediate and drastic steps to halt global heating.

Researchers have found that surface melting is at a rate that has begun to make the glaciers more unstable. They have confirmed that the rate of melt is accelerating so swiftly that the bedrock beneath the weight of ice has begun to rise, while a range of other climate change triggers has begun to darken the ice cover in ways that can only increase the absorption of heat and step up the rate of melt.

The latest evidence is that the world has passed a tipping point of sorts: once such things happen, there is no way back.

Glaciers gather speed

All icecaps melt in summer, and all icecaps are drained by glaciers, rivers of ice that make slow progress to the sea. In a stable climate, annual precipitation and annual glacier calving remain more or less in balance, and the icecap functions as its own refrigerant. The whiteness of the ice reflects sunlight back into space and insulates itself against significant loss.

But as the air and oceans warm in response to ever higher levels of greenhouse gases pumped into the atmosphere as nations continue to burn ever more coal, oil and gas, the rates of melt became more dramatic and the glaciers began to flow ever faster: one of them was clocked at 45 metres a day.

The message of the latest research is that, even if somehow humans could immediately halt climate change, the ice likely to be lost as the glaciers reach the sea would still be greater than the accumulation of ice on the surface each winter.

“Glacier retreat has knocked the dynamics of the whole ice sheet into a constant state of loss,” said Ian Howat, a co-author at Ohio State University. “Even if the climate were to stay the same or get a little colder, the ice sheet would still be losing mass.” – Climate News Network

Cloudless skies hasten Greenland’s ice loss

This story is a part of Covering Climate Now’s week of coverage focused on Climate Solutions, to mark the 50th anniversary of Earth Day. Covering Climate Now is a global journalism collaboration committed to strengthening coverage of the climate story.

 

The bad news about Greenland’s ice loss has just got even worse. Blame it on mischief by blue skies all day long.

LONDON, 22 April, 2020 – Greenland’s ice loss reached record levels in 2019, and scientists think they’ve identified the culprit: the good weather which normally brings the snow-bearing clouds to the High Arctic.

The huge island, the biggest bank of ice in the northern hemisphere, has been losing ice at an ever-increasing rate in a rapidly warming world. Last year it shed more ice than ever, and this time because the skies were unusually clear.

There is enough ice on Greenland to raise global sea levels by more than seven metres. A recent study established that in the years between 1992 and 2018, rates of polar ice loss have risen six-fold, and so much water has flowed off the Greenland ice surface that sea levels have risen by more than 10mm everywhere.

Now a new study by US and Belgian scientists in the journal The Cryosphere confirms that 2019 was even worse. Because of good weather and cloudless skies, only enough snow fell to deposit 50 billion tonnes of ice into the island’s profit-and-loss ice account. The average annual deposit between 1981 and 2010 was about 375bn tonnes.

But glaciers still flowed towards the sea at an ever-increasing rate, summer snow melt continued to flow off the ice sheet, and icebergs continued to calve, so on balance the island lost 600 billion tonnes of ice: enough to raise global sea levels by 1.5mm. This is the biggest overall loss of ice since records in Greenland began in 1948.

“These atmospheric conditions are becoming more and more frequent over the past few decades. It is very likely that this is due to the waviness of the jet stream”

The cause: unusual spells of high atmospheric pressure over the island for unusually long periods of time. That stopped the formation of clouds, and that meant less precipitation, in the form of snow. Snow reflects solar radiation more effectively than ice, so the surface absorbed more heat and melting also accelerated.

The pattern of warm moist clouds trapped over northern Greenland by the heat that would normally radiate off the ice, instead of releasing snow, also emitted their own heat, to make things worse. The worst year for surface melting remains 2012, but the summer of 2019 was a good second.

The implication is that things could get worse, and losses of Greenland ice could accelerate.

“These atmospheric conditions are becoming more and more frequent over the past few decades,” said Marco Tedesco, of the Lamont-Doherty Earth Observatory at the University of Columbia in the US, the lead author.

“It is very likely that this is due to the waviness of the jet stream, which we think is related to, among other things, the disappearance of snow cover in Siberia, the disappearance of sea ice, and the difference in the rate at which temperature is increasing in the Arctic versus the mid-latitudes.” – Climate News Network

This story is a part of Covering Climate Now’s week of coverage focused on Climate Solutions, to mark the 50th anniversary of Earth Day. Covering Climate Now is a global journalism collaboration committed to strengthening coverage of the climate story.

 

The bad news about Greenland’s ice loss has just got even worse. Blame it on mischief by blue skies all day long.

LONDON, 22 April, 2020 – Greenland’s ice loss reached record levels in 2019, and scientists think they’ve identified the culprit: the good weather which normally brings the snow-bearing clouds to the High Arctic.

The huge island, the biggest bank of ice in the northern hemisphere, has been losing ice at an ever-increasing rate in a rapidly warming world. Last year it shed more ice than ever, and this time because the skies were unusually clear.

There is enough ice on Greenland to raise global sea levels by more than seven metres. A recent study established that in the years between 1992 and 2018, rates of polar ice loss have risen six-fold, and so much water has flowed off the Greenland ice surface that sea levels have risen by more than 10mm everywhere.

Now a new study by US and Belgian scientists in the journal The Cryosphere confirms that 2019 was even worse. Because of good weather and cloudless skies, only enough snow fell to deposit 50 billion tonnes of ice into the island’s profit-and-loss ice account. The average annual deposit between 1981 and 2010 was about 375bn tonnes.

But glaciers still flowed towards the sea at an ever-increasing rate, summer snow melt continued to flow off the ice sheet, and icebergs continued to calve, so on balance the island lost 600 billion tonnes of ice: enough to raise global sea levels by 1.5mm. This is the biggest overall loss of ice since records in Greenland began in 1948.

“These atmospheric conditions are becoming more and more frequent over the past few decades. It is very likely that this is due to the waviness of the jet stream”

The cause: unusual spells of high atmospheric pressure over the island for unusually long periods of time. That stopped the formation of clouds, and that meant less precipitation, in the form of snow. Snow reflects solar radiation more effectively than ice, so the surface absorbed more heat and melting also accelerated.

The pattern of warm moist clouds trapped over northern Greenland by the heat that would normally radiate off the ice, instead of releasing snow, also emitted their own heat, to make things worse. The worst year for surface melting remains 2012, but the summer of 2019 was a good second.

The implication is that things could get worse, and losses of Greenland ice could accelerate.

“These atmospheric conditions are becoming more and more frequent over the past few decades,” said Marco Tedesco, of the Lamont-Doherty Earth Observatory at the University of Columbia in the US, the lead author.

“It is very likely that this is due to the waviness of the jet stream, which we think is related to, among other things, the disappearance of snow cover in Siberia, the disappearance of sea ice, and the difference in the rate at which temperature is increasing in the Arctic versus the mid-latitudes.” – Climate News Network

Record Antarctic temperatures fuel sea level worry


Sea levels may threaten coastal cities sooner than expected, scientists say, as ice loss speeds up and Antarctic temperatures rise.

LONDON, 20 February, 2020 − Across the world, people now alive in coastal areas may face dangerously rising seas within their lifetimes, as record Antarctic temperatures and rapid melting of the continent’s ice drive global sea levels upwards.

Temperatures on the Antarctic Peninsula reached more than 20°C for the first time in history earlier this month, the Guardian reported: “The 20.75C logged by Brazilian scientists at Seymour Island on 9 February was almost a full degree higher than the previous record of 19.8C, taken on Signy Island in January 1982.”

The Antarctic Peninsula has warmed by almost 3°C since the start of the Industrial Revolution around 200 years ago − faster than almost anywhere else on Earth. But scientists are increasingly concerned not only about the Peninsula, but with the possibility that the entire southern continent may be heating up much faster than current estimates suggest.

Among evidence of increasing scientific effort to determine what is happening is a joint UK-US collaboration, due to report in 2023 on the chances of the collapse of the huge Thwaites glacier in West Antarctica, where from 1992 to 2017 the annual rate of ice loss rose threefold.

Big speed-up

Now a study by scientists co-ordinated by Germany’s Potsdam Institute for Climate Impact Research (PIK) says sea level rise caused by Antarctica’s ice loss could become a major risk for coastal protection in the near future.

After what they call “an exceptionally comprehensive comparison of state-of-the-art computer models from around the world”, they conclude that Antarctica alone could cause global sea level to rise by 2100 by up to three times more than it did in the last century.

“The ‘Antarctica Factor’ turns out to be the greatest risk, and also the greatest uncertainty, for sea levels around the globe,” says the lead author, Anders Levermann of PIK and Columbia University’s Lamont-Doherty Earth Observatory (LDEO) in New York.

“While we saw about 19 centimetres of sea level rise in the past 100 years, Antarctic ice loss could lead to up to 58 centimetres within this century”, he said.

“We know for certain that not stopping the burning of coal, oil and gas will drive up the risks for coastal metropolises from New York to Mumbai, Hamburg and Shanghai”

“Coastal planning cannot merely rely on the best guess. It requires a risk analysis. Our study provides exactly that. The sea level contribution of Antarctica is very likely not going to be more than 58 centimetres.”

Thermal expansion of the oceans by global warming and the melting of glaciers, which so far have been the most important factors in sea level rise, will add to the contribution from Antarctic ice loss, making the overall sea level rise risk even bigger. But the ‘Antarctica Factor’ is about to become the most important element, according to the study, published in the journal Earth System Dynamics.

The range of sea-level rise estimates the scientists have come up with is fairly large. Assuming that humanity keeps on emitting greenhouse gases as before, they say, the range they call “very likely” to describe the future is between 6 and 58 cms for this century.

If greenhouse gas emissions were reduced rapidly, it would be between 4 and 37 cms. Importantly, the difference between a business-as-usual scenario and one of emissions reductions becomes substantially greater as time passes.

More robust insights

Sixteen ice sheet modelling groups consisting of 36 researchers from 27 institutes contributed to the new study. A similar study six years ago had to rely on the output of only five ice sheet models.

“The more computer simulation models we use, all of them with slightly different dynamic representations of the Antarctic ice sheet, the wider the range of results that we yield − but also the more robust the insights that we gain”, said co-author Sophie Nowicki of the NASA Goddard Space Flight Center.

“There are still large uncertainties, but we are constantly improving our understanding of the largest ice sheet on Earth. Comparing model outputs is a forceful tool to provide society with the necessary information for rational decisions.”

Over the long term, the Antarctic ice sheet has the potential ultimately to raise sea levels by many tens of metres. “What we know for certain”, said Professor Levermann, “is that not stopping the burning of coal, oil and gas will drive up the risks for coastal metropolises from New York to Mumbai, Hamburg and Shanghai.” − Climate News Network


Sea levels may threaten coastal cities sooner than expected, scientists say, as ice loss speeds up and Antarctic temperatures rise.

LONDON, 20 February, 2020 − Across the world, people now alive in coastal areas may face dangerously rising seas within their lifetimes, as record Antarctic temperatures and rapid melting of the continent’s ice drive global sea levels upwards.

Temperatures on the Antarctic Peninsula reached more than 20°C for the first time in history earlier this month, the Guardian reported: “The 20.75C logged by Brazilian scientists at Seymour Island on 9 February was almost a full degree higher than the previous record of 19.8C, taken on Signy Island in January 1982.”

The Antarctic Peninsula has warmed by almost 3°C since the start of the Industrial Revolution around 200 years ago − faster than almost anywhere else on Earth. But scientists are increasingly concerned not only about the Peninsula, but with the possibility that the entire southern continent may be heating up much faster than current estimates suggest.

Among evidence of increasing scientific effort to determine what is happening is a joint UK-US collaboration, due to report in 2023 on the chances of the collapse of the huge Thwaites glacier in West Antarctica, where from 1992 to 2017 the annual rate of ice loss rose threefold.

Big speed-up

Now a study by scientists co-ordinated by Germany’s Potsdam Institute for Climate Impact Research (PIK) says sea level rise caused by Antarctica’s ice loss could become a major risk for coastal protection in the near future.

After what they call “an exceptionally comprehensive comparison of state-of-the-art computer models from around the world”, they conclude that Antarctica alone could cause global sea level to rise by 2100 by up to three times more than it did in the last century.

“The ‘Antarctica Factor’ turns out to be the greatest risk, and also the greatest uncertainty, for sea levels around the globe,” says the lead author, Anders Levermann of PIK and Columbia University’s Lamont-Doherty Earth Observatory (LDEO) in New York.

“While we saw about 19 centimetres of sea level rise in the past 100 years, Antarctic ice loss could lead to up to 58 centimetres within this century”, he said.

“We know for certain that not stopping the burning of coal, oil and gas will drive up the risks for coastal metropolises from New York to Mumbai, Hamburg and Shanghai”

“Coastal planning cannot merely rely on the best guess. It requires a risk analysis. Our study provides exactly that. The sea level contribution of Antarctica is very likely not going to be more than 58 centimetres.”

Thermal expansion of the oceans by global warming and the melting of glaciers, which so far have been the most important factors in sea level rise, will add to the contribution from Antarctic ice loss, making the overall sea level rise risk even bigger. But the ‘Antarctica Factor’ is about to become the most important element, according to the study, published in the journal Earth System Dynamics.

The range of sea-level rise estimates the scientists have come up with is fairly large. Assuming that humanity keeps on emitting greenhouse gases as before, they say, the range they call “very likely” to describe the future is between 6 and 58 cms for this century.

If greenhouse gas emissions were reduced rapidly, it would be between 4 and 37 cms. Importantly, the difference between a business-as-usual scenario and one of emissions reductions becomes substantially greater as time passes.

More robust insights

Sixteen ice sheet modelling groups consisting of 36 researchers from 27 institutes contributed to the new study. A similar study six years ago had to rely on the output of only five ice sheet models.

“The more computer simulation models we use, all of them with slightly different dynamic representations of the Antarctic ice sheet, the wider the range of results that we yield − but also the more robust the insights that we gain”, said co-author Sophie Nowicki of the NASA Goddard Space Flight Center.

“There are still large uncertainties, but we are constantly improving our understanding of the largest ice sheet on Earth. Comparing model outputs is a forceful tool to provide society with the necessary information for rational decisions.”

Over the long term, the Antarctic ice sheet has the potential ultimately to raise sea levels by many tens of metres. “What we know for certain”, said Professor Levermann, “is that not stopping the burning of coal, oil and gas will drive up the risks for coastal metropolises from New York to Mumbai, Hamburg and Shanghai.” − Climate News Network

Speeding sea level rise threatens nuclear plants

With sea level rise accelerating faster than thought, the risk is growing for coastal cities − and for nuclear power stations.

LONDON, 14 February, 2020 − The latest science shows how the pace of sea level rise is speeding up, fuelling fears that not only millions of homes will be under threat, but that vulnerable installations like docks and power plants will be overwhelmed by the waves.

New research using satellite data over a 30-year period shows that around the year 2000 sea level rise was 2mm a year, by 2010 it was 3mm and now it is at 4mm, with the pace of change still increasing.

The calculations were made by a research student, Tadea Veng, at the Technical University of Denmark, which has a special interest in Greenland, where the icecap is melting fast. That, combined with accelerating melting in Antarctica and further warming of the oceans, is raising sea levels across the globe.

The report coincides with a European Environment Agency (EEA) study whose maps show large areas of the shorelines of countries with coastlines on the North Sea will go under water unless heavily defended against sea level rise.

Based on the maps, newspapers like The Guardian in London have predicted that more than half of one key UK east coast provincial port − Hull − will be swamped. Ironically, Hull is the base for making giant wind turbine blades for use in the North Sea.

“It’s not just the height of the rise in sea level that is important for the protection of nuclear facilities, it’s also the likely increase in storm surges”

The argument about how much the sea level will rise this century has been raging in scientific circles since the 1990s. At the start, predictions of sea level rise took into account only two possible causes: the expansion of seawater as it warmed, and the melting of mountain glaciers away from the poles.

In the early Intergovernmental Panel on Climate Change reports back then, the melting of the polar ice caps was not included, because scientists could not agree whether greater snowfall on the top of the ice caps in winter might balance out summer melting. Many of them also thought Antarctica would not melt at all, or not for centuries, because it was too cold.

Both the extra snow theory and the “too cold to melt” idea have now been discounted. In Antarctica this is partly because the sea has warmed up so much that it is melting the glaciers’ ice from beneath – something the scientists had not foreseen.

Alarm about sea level rise elsewhere has been increasing outside the scientific community, partly because many nuclear power plants are on coasts. Even those that are nearing the end of their working lives will be radio-active for another century, and many have highly dangerous spent fuel on site in storage ponds with no disposal route organised.

Perhaps most alarmed are British residents, whose government is currently planning a number of new seaside nuclear stations in low-lying coastal areas. Some will be under water this century according to the EEA, particularly one planned for Sizewell in eastern England.

Hard to tell

The Agency’s report says estimates of sea level rise by 2100 vary, with an upper limit of one metre generally accepted, but up to 2.5 metres predicted by some scientists. The latest research by Danish scientists suggests judiciously that with the speed of sea level rise continuing to accelerate, it is impossible to be sure.

A report by campaigners who oppose building nuclear power stations on Britain’s vulnerable coast expresses extreme alarm, saying both nuclear regulators and the giant French energy company EDF are too complacent about the problem.

The report says: “Polar ice caps appear to be melting faster than expected, and what is particularly worrying is that the rate of melting seems to be increasing. Some researchers say sea levels could rise by as much as six metres or more by 2100, even if the 2°C Paris targethttps://unfccc.int/process-and-meetings/the-paris-agreement/the-paris-agreement is met.

“But it’s not just the height of the rise in sea level that is important for the protection of nuclear facilities, it’s also the likely increase in storm surges. An increase in sea level of 50cm would mean the storm that used to come every thousand years will now come every 100 years. If you increase that to a metre, then that millennial storm is likely to come once a decade.

“Bearing in mind that there will probably be nuclear waste on the Hinkley Point C site [home to the new twin reactors being built by EDF in the West of England] until at least 2150, the question neither the Office of Nuclear Regulation nor EDF seem to be asking is whether further flood protection measures can be put in place fast enough to deal with unexpected and unpredicted storm surges.” − Climate News Network

With sea level rise accelerating faster than thought, the risk is growing for coastal cities − and for nuclear power stations.

LONDON, 14 February, 2020 − The latest science shows how the pace of sea level rise is speeding up, fuelling fears that not only millions of homes will be under threat, but that vulnerable installations like docks and power plants will be overwhelmed by the waves.

New research using satellite data over a 30-year period shows that around the year 2000 sea level rise was 2mm a year, by 2010 it was 3mm and now it is at 4mm, with the pace of change still increasing.

The calculations were made by a research student, Tadea Veng, at the Technical University of Denmark, which has a special interest in Greenland, where the icecap is melting fast. That, combined with accelerating melting in Antarctica and further warming of the oceans, is raising sea levels across the globe.

The report coincides with a European Environment Agency (EEA) study whose maps show large areas of the shorelines of countries with coastlines on the North Sea will go under water unless heavily defended against sea level rise.

Based on the maps, newspapers like The Guardian in London have predicted that more than half of one key UK east coast provincial port − Hull − will be swamped. Ironically, Hull is the base for making giant wind turbine blades for use in the North Sea.

“It’s not just the height of the rise in sea level that is important for the protection of nuclear facilities, it’s also the likely increase in storm surges”

The argument about how much the sea level will rise this century has been raging in scientific circles since the 1990s. At the start, predictions of sea level rise took into account only two possible causes: the expansion of seawater as it warmed, and the melting of mountain glaciers away from the poles.

In the early Intergovernmental Panel on Climate Change reports back then, the melting of the polar ice caps was not included, because scientists could not agree whether greater snowfall on the top of the ice caps in winter might balance out summer melting. Many of them also thought Antarctica would not melt at all, or not for centuries, because it was too cold.

Both the extra snow theory and the “too cold to melt” idea have now been discounted. In Antarctica this is partly because the sea has warmed up so much that it is melting the glaciers’ ice from beneath – something the scientists had not foreseen.

Alarm about sea level rise elsewhere has been increasing outside the scientific community, partly because many nuclear power plants are on coasts. Even those that are nearing the end of their working lives will be radio-active for another century, and many have highly dangerous spent fuel on site in storage ponds with no disposal route organised.

Perhaps most alarmed are British residents, whose government is currently planning a number of new seaside nuclear stations in low-lying coastal areas. Some will be under water this century according to the EEA, particularly one planned for Sizewell in eastern England.

Hard to tell

The Agency’s report says estimates of sea level rise by 2100 vary, with an upper limit of one metre generally accepted, but up to 2.5 metres predicted by some scientists. The latest research by Danish scientists suggests judiciously that with the speed of sea level rise continuing to accelerate, it is impossible to be sure.

A report by campaigners who oppose building nuclear power stations on Britain’s vulnerable coast expresses extreme alarm, saying both nuclear regulators and the giant French energy company EDF are too complacent about the problem.

The report says: “Polar ice caps appear to be melting faster than expected, and what is particularly worrying is that the rate of melting seems to be increasing. Some researchers say sea levels could rise by as much as six metres or more by 2100, even if the 2°C Paris targethttps://unfccc.int/process-and-meetings/the-paris-agreement/the-paris-agreement is met.

“But it’s not just the height of the rise in sea level that is important for the protection of nuclear facilities, it’s also the likely increase in storm surges. An increase in sea level of 50cm would mean the storm that used to come every thousand years will now come every 100 years. If you increase that to a metre, then that millennial storm is likely to come once a decade.

“Bearing in mind that there will probably be nuclear waste on the Hinkley Point C site [home to the new twin reactors being built by EDF in the West of England] until at least 2150, the question neither the Office of Nuclear Regulation nor EDF seem to be asking is whether further flood protection measures can be put in place fast enough to deal with unexpected and unpredicted storm surges.” − 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