Tag Archives: climate change

Seas and forests are muddying the carbon budget

As climates change, forests may not absorb more carbon as expected. But a new carbon budget could appeal to the oceans.

LONDON, 18 September 2020 – Two new studies could throw long-term climate forecasts into confusion. The planetary carbon budget – the all-important traffic of life’s first element between rocks, water, atmosphere and living things – that underpins planetary temperatures and maintains a stable climate needs a rethink.

A warming climate makes trees grow faster. The awkward finding is that  faster-growing trees die younger. Therefore they must surrender their carbon back to the atmosphere quicker.

So tomorrow’s forests may not be quite such reliable long-term banks of carbon pumped into the atmosphere as a consequence of profligate fossil fuel use by human economies.

The more reassuring news is that the ocean – that’s almost three fourths of the planet’s surface – may absorb and store a lot more atmospheric carbon than previous estimates suggest.

All calculations about the future rate of global heating, and the potential consequences of climate change, rest upon the carbon budget.

Forest doubts

This is the intricate accounting of the mass of carbon in continuous circulation from air to plant to animal and then to shell, skeleton and sediment, and the expected flow of carbon emissions from the combustion of fossil fuels stored hundreds of millions of years ago, and exhumed in the last two centuries.

To make sense of the factors at work, climate scientists have to make calculations about all the carbon stored in the permafrost, in the soils, in the forests, dissolved in the oceans, free in the atmosphere and being released from power station chimneys, vehicle exhausts and ploughed or scorched land.

But for decades, one component of the equation has been automatically accepted: more forests must mean more carbon absorbed, and better protected natural forests would store the most carbon, the most efficiently.

Now a new report in the journal Nature Communications introduces some doubt into this cornerstone of the carbon budget. In an already warming world, much more of the carbon stored in tomorrow’s forests might find its way back into the atmosphere.

Researchers looked at 200,000 tree ring records from 82 tree species from sites around the planet. They found what they describe as trade-offs that are near universal: faster-growing trees have shorter lives.

“There is likely to be a timelag before we see the worst of the potential loss of carbon stocks from increases in tree mortality”

This was true in cool climates and warm ones, and in all species. So the hope that natural vegetation will respond to warmer temperatures by absorbing even more carbon becomes insecure, especially if it means that the more vigorous growth means simply swifter death and decay.

“Our modeling suggests that there is likely to be a timelag before we see the worst of the potential loss of carbon stocks from increases in tree mortality,” said Roel Brienen of the University of Leeds in the UK, who led the research. “They estimate that global increases in tree death don’t kick in until after sites show accelerated growth.”

All such research is provisional: the findings gain currency only when supported by other teams using different approaches. So it has yet to be confirmed.

But recent studies have suggested that climate change has already begun to complicate calculations. Just in recent months, research teams have found that forest trees are growing shorter and dying younger; that higher temperatures may affect plant germination; and that forests already hit by drought may start surrendering carbon more swiftly than they absorb it. Planting more trees is not an alternative to reducing greenhouse gas emissions.

On the other hand, the carbon budget may still make sense: the oceans may be responding to ever-higher concentrations of carbon dioxide by absorbing more from the atmosphere, which also makes the oceans more acidic, which is not necessarily helpful.

Oceans’ effect

All such calculations are based on sea surface temperatures. Gases such as carbon dioxide and oxygen dissolve well in colder water, not so well in warm lagoons and tropical tides.

But a British group reports in the same journal that calculations so far may have been under-estimates. This is because, on balance, researchers have tended to ignore the small difference between the temperatures at the surface, and a few metres down, where the measurements of dissolved greenhouse gas were actually made.

A team from the University of Exeter worked from a global database to make new estimates of the oceans’ appetite for carbon between 1992 and 2018.

“We used satellite data to correct for these temperature differences, and when we do that, it makes a big difference – we get a substantially larger flux going into the ocean,” said Andrew Watson, who led the study.

“The difference in ocean uptake we calculate amounts to 10% of global fossil fuel emissions.” – Climate News Network

As climates change, forests may not absorb more carbon as expected. But a new carbon budget could appeal to the oceans.

LONDON, 18 September 2020 – Two new studies could throw long-term climate forecasts into confusion. The planetary carbon budget – the all-important traffic of life’s first element between rocks, water, atmosphere and living things – that underpins planetary temperatures and maintains a stable climate needs a rethink.

A warming climate makes trees grow faster. The awkward finding is that  faster-growing trees die younger. Therefore they must surrender their carbon back to the atmosphere quicker.

So tomorrow’s forests may not be quite such reliable long-term banks of carbon pumped into the atmosphere as a consequence of profligate fossil fuel use by human economies.

The more reassuring news is that the ocean – that’s almost three fourths of the planet’s surface – may absorb and store a lot more atmospheric carbon than previous estimates suggest.

All calculations about the future rate of global heating, and the potential consequences of climate change, rest upon the carbon budget.

Forest doubts

This is the intricate accounting of the mass of carbon in continuous circulation from air to plant to animal and then to shell, skeleton and sediment, and the expected flow of carbon emissions from the combustion of fossil fuels stored hundreds of millions of years ago, and exhumed in the last two centuries.

To make sense of the factors at work, climate scientists have to make calculations about all the carbon stored in the permafrost, in the soils, in the forests, dissolved in the oceans, free in the atmosphere and being released from power station chimneys, vehicle exhausts and ploughed or scorched land.

But for decades, one component of the equation has been automatically accepted: more forests must mean more carbon absorbed, and better protected natural forests would store the most carbon, the most efficiently.

Now a new report in the journal Nature Communications introduces some doubt into this cornerstone of the carbon budget. In an already warming world, much more of the carbon stored in tomorrow’s forests might find its way back into the atmosphere.

Researchers looked at 200,000 tree ring records from 82 tree species from sites around the planet. They found what they describe as trade-offs that are near universal: faster-growing trees have shorter lives.

“There is likely to be a timelag before we see the worst of the potential loss of carbon stocks from increases in tree mortality”

This was true in cool climates and warm ones, and in all species. So the hope that natural vegetation will respond to warmer temperatures by absorbing even more carbon becomes insecure, especially if it means that the more vigorous growth means simply swifter death and decay.

“Our modeling suggests that there is likely to be a timelag before we see the worst of the potential loss of carbon stocks from increases in tree mortality,” said Roel Brienen of the University of Leeds in the UK, who led the research. “They estimate that global increases in tree death don’t kick in until after sites show accelerated growth.”

All such research is provisional: the findings gain currency only when supported by other teams using different approaches. So it has yet to be confirmed.

But recent studies have suggested that climate change has already begun to complicate calculations. Just in recent months, research teams have found that forest trees are growing shorter and dying younger; that higher temperatures may affect plant germination; and that forests already hit by drought may start surrendering carbon more swiftly than they absorb it. Planting more trees is not an alternative to reducing greenhouse gas emissions.

On the other hand, the carbon budget may still make sense: the oceans may be responding to ever-higher concentrations of carbon dioxide by absorbing more from the atmosphere, which also makes the oceans more acidic, which is not necessarily helpful.

Oceans’ effect

All such calculations are based on sea surface temperatures. Gases such as carbon dioxide and oxygen dissolve well in colder water, not so well in warm lagoons and tropical tides.

But a British group reports in the same journal that calculations so far may have been under-estimates. This is because, on balance, researchers have tended to ignore the small difference between the temperatures at the surface, and a few metres down, where the measurements of dissolved greenhouse gas were actually made.

A team from the University of Exeter worked from a global database to make new estimates of the oceans’ appetite for carbon between 1992 and 2018.

“We used satellite data to correct for these temperature differences, and when we do that, it makes a big difference – we get a substantially larger flux going into the ocean,” said Andrew Watson, who led the study.

“The difference in ocean uptake we calculate amounts to 10% of global fossil fuel emissions.” – Climate News Network

Slightest heat increase magnifies hurricane risk

The poorer and more vulnerable you are, the greater your hurricane risk. Even a tiny heat rise can spell disaster.

LONDON, 11 September, 2020 – Any climate change at all will mean a hurricane risk for the storm-prone Caribbean, even if global average temperatures are contained to a rise of no more than 1.5°C by 2100. But a rise of 2°C could be disastrous: the hurricane hazard could grow fivefold.

The figures – each representing a rise above the long-term average for most of human history – are significant. In 2015 195 nations, including the US, signed up to the Paris Agreement – a promise to contain the rise in global heating to “well below 2°C” by the century’s end. The undeclared but widely-understood intention was a limit of 1.5°C.

In the last century, in response to a rise in carbon dioxide emissions from fossil fuel use, planetary average temperatures have already risen by 1°C, and the Atlantic states of the US and the islands of the Caribbean have been hit by a series of ever more devastating windstorms, as ocean temperatures warm and make hurricanes more probable.

And researchers warn that as global heating continues – with forecasts of a rise of more than 3°C by 2100 – more are on the way.

But the US is wealthy and resilient. British scientists report in the journal Environmental Research Letters that they decided to take a look at the probability of windstorm and heavy rainfall assault on the Caribbean, where half of the 44 million people of the archipelago live within 1.5kms of the coast, and where devastation can be so intense it could take six years to recover.

“The findings are alarming and illustrate the urgent need to tackle global warming to reduce the likelihood of extreme rainfall events”

So they used computer simulations to generate thousands of synthetic hurricanes, under three climate scenarios: present day conditions; a world that kept global heating to no more than 1.5C; and one in which nations let rip and hit the 2°C limit.

They found that extreme rainfall events of the kind which typically happen once every hundred years at present do indeed become more numerous in a world that sticks to its implicit Paris promise. But in a 2°C warmer world, calamitous hurricanes became five times more frequent.

When Hurricane Maria hit Puerto Rico in 2017, it delivered a quarter of a year’s average rainfall all at once, with appalling consequences. In a two-degree warmer world, such a storm could happen every 43 years. The storm that hit the Bahamas in 2019 could become 4.5 times more likely.

“The findings are alarming and illustrate the urgent need to tackle global warming to reduce the likelihood of extreme rainfall events and their catastrophic consequences, particularly for poorer countries which take many years to recover,” said Emily Vosper of the University of Bristol, who led the study.

“We expected extreme hurricanes to be more prevalent in the 2°C global warming scenario, but the scale of the projected increases was surprising, and should serve as a stark warning across the globe, underscoring the importance of keeping climate change under control.” – Climate News Network

The poorer and more vulnerable you are, the greater your hurricane risk. Even a tiny heat rise can spell disaster.

LONDON, 11 September, 2020 – Any climate change at all will mean a hurricane risk for the storm-prone Caribbean, even if global average temperatures are contained to a rise of no more than 1.5°C by 2100. But a rise of 2°C could be disastrous: the hurricane hazard could grow fivefold.

The figures – each representing a rise above the long-term average for most of human history – are significant. In 2015 195 nations, including the US, signed up to the Paris Agreement – a promise to contain the rise in global heating to “well below 2°C” by the century’s end. The undeclared but widely-understood intention was a limit of 1.5°C.

In the last century, in response to a rise in carbon dioxide emissions from fossil fuel use, planetary average temperatures have already risen by 1°C, and the Atlantic states of the US and the islands of the Caribbean have been hit by a series of ever more devastating windstorms, as ocean temperatures warm and make hurricanes more probable.

And researchers warn that as global heating continues – with forecasts of a rise of more than 3°C by 2100 – more are on the way.

But the US is wealthy and resilient. British scientists report in the journal Environmental Research Letters that they decided to take a look at the probability of windstorm and heavy rainfall assault on the Caribbean, where half of the 44 million people of the archipelago live within 1.5kms of the coast, and where devastation can be so intense it could take six years to recover.

“The findings are alarming and illustrate the urgent need to tackle global warming to reduce the likelihood of extreme rainfall events”

So they used computer simulations to generate thousands of synthetic hurricanes, under three climate scenarios: present day conditions; a world that kept global heating to no more than 1.5C; and one in which nations let rip and hit the 2°C limit.

They found that extreme rainfall events of the kind which typically happen once every hundred years at present do indeed become more numerous in a world that sticks to its implicit Paris promise. But in a 2°C warmer world, calamitous hurricanes became five times more frequent.

When Hurricane Maria hit Puerto Rico in 2017, it delivered a quarter of a year’s average rainfall all at once, with appalling consequences. In a two-degree warmer world, such a storm could happen every 43 years. The storm that hit the Bahamas in 2019 could become 4.5 times more likely.

“The findings are alarming and illustrate the urgent need to tackle global warming to reduce the likelihood of extreme rainfall events and their catastrophic consequences, particularly for poorer countries which take many years to recover,” said Emily Vosper of the University of Bristol, who led the study.

“We expected extreme hurricanes to be more prevalent in the 2°C global warming scenario, but the scale of the projected increases was surprising, and should serve as a stark warning across the globe, underscoring the importance of keeping climate change under control.” – 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

Rivers flood, seas rise – and land faces erosion

Polar melting cannot be separated from farmland soil erosion and estuarine flooding. All are part of climate change.

LONDON, 7 September, 2020 – Climate heating often ensures that calamities don’t come singly: so don’t forget what erosion can do.

In a warmer world the glaciers will melt ever faster to raise global sea levels ever higher. In a wetter world, more and more topsoil will be swept off the farmlands and downriver into the ever-rising seas.

And the pay-off of silt-laden rivers and rising sea levels could be catastrophic floods, as swollen rivers suddenly change course. Since many of the world’s greatest cities are built on river estuaries, lives and economies will be at risk.

Three new studies in two journals deliver a sharp reminder that the consequences of global heating are not straightforward: the world responds to change in unpredictable ways.

First: the melting of the ice sheets and the mountain glaciers. Researchers warn in the journal Nature Climate Change that if the loss of ice from Antarctica, Greenland and the frozen rivers continues, then climate forecasters and government agencies will have to think again: sea levels could rise to at least 17cms higher than the worst predictions so far.

“Avulsions are the earthquakes of rivers. They are sudden and sometimes catastrophic. We are trying to understand where and when the next avulsions will occur”

That means an additional 16 million people at hazard from estuarine floods and storm surges.

In the last 30 years, the flow from the Antarctic ice cap has raised sea levels by 7.2mm, and from Greenland by 10.6mm. Every year, the world’s oceans are 4mm higher than they were the year before.

“Although we anticipated the ice sheets would lose increasing amounts of ice in response to the warming of the oceans and the atmosphere, the rate at which they are melting has accelerated faster than we could have imagined,” said Tom Slater of the University of Leeds, in the UK, who led the research.

“The melting is overtaking the climate models we use to guide us, and we are in danger of being unprepared for the risks posed by sea level rise.”

Dr Slater and his colleagues are the third team to warn in the last month that observations of climate already match the worst-case scenarios dreamed up by forecasters preparing for a range of possible climate outcomes.

Erosion risk rises

The latest reading of glacial melt rates suggests that the risk of storm surges for many of the world’s greatest cities will double by the close of the century. But coastal cities – and the farmers who already work 38% of the terrestrial surface to feed almost 8bn people – have another more immediate problem.

In a warmer world, more water evaporates. In a warmer atmosphere, the capacity of the air to hold moisture also increases, so along with more intense droughts, heavier rainfall is on the way for much of the world. And the heavier the rain, or the more prolonged the drought, the higher the risk of soil erosion.

In 2015 the world’s farmers and foresters watched 43 billion tonnes of topsoil wash away from hillsides or blow away from tilled land and into the sea. By 2070, this burden of silt swept away by water or blown by wind will have risen by between 30% and 66%: probably more than 28 bn tons of additional loss.

This could only impoverish the farmland, according to a study by Swiss scientists in the Proceedings of the National Academy of Sciences. It could also impoverish people, communities and countries. The worst hit could be in the less developed nations of the tropics and subtropics.

But the flow of ever-higher silt levels into ever-rising seas also raises a new hazard: hydrologists call it river avulsion. It’s a simple and natural process. As conditions change, so rivers will naturally change their flow to spill over new floodplains and extend coastal lands.

Survival in question

But river avulsions can also be helped along by rising sea levels. Since 10% of humanity is crowded into rich, fertile delta lands, and since some of the deadliest floods in human history – two in China in 1887 and 1931 claimed six million lives – have been caused by river avulsions, the question becomes a matter of life and death.

US scientists report, also in the Proceedings of the National Academy of Sciences, that rising sea levels alone could make abrupt river avulsion more probable, especially as delta lands could be subsiding, because of groundwater and other extraction.

The dangers of avulsion are affected by the rate of sediment deposit in the river channels, and this is likely to rise with sea levels. This in turn raises the level of the river and eventually a breach of a levee or other flood defence will force the river to find a swifter, steeper path to the sea.

Cities such as New Orleans and the coastal communities of the Mississippi delta are already vulnerable. “Avulsions are the earthquakes of rivers,” said Michael Lamb, of California Institute of Technology, one of the authors.

“They are sudden and sometimes catastrophic natural events that occur with statistical regularity, shifting the direction of major rivers. We are trying to understand where and when the next avulsions will occur.” – Climate News Network

Polar melting cannot be separated from farmland soil erosion and estuarine flooding. All are part of climate change.

LONDON, 7 September, 2020 – Climate heating often ensures that calamities don’t come singly: so don’t forget what erosion can do.

In a warmer world the glaciers will melt ever faster to raise global sea levels ever higher. In a wetter world, more and more topsoil will be swept off the farmlands and downriver into the ever-rising seas.

And the pay-off of silt-laden rivers and rising sea levels could be catastrophic floods, as swollen rivers suddenly change course. Since many of the world’s greatest cities are built on river estuaries, lives and economies will be at risk.

Three new studies in two journals deliver a sharp reminder that the consequences of global heating are not straightforward: the world responds to change in unpredictable ways.

First: the melting of the ice sheets and the mountain glaciers. Researchers warn in the journal Nature Climate Change that if the loss of ice from Antarctica, Greenland and the frozen rivers continues, then climate forecasters and government agencies will have to think again: sea levels could rise to at least 17cms higher than the worst predictions so far.

“Avulsions are the earthquakes of rivers. They are sudden and sometimes catastrophic. We are trying to understand where and when the next avulsions will occur”

That means an additional 16 million people at hazard from estuarine floods and storm surges.

In the last 30 years, the flow from the Antarctic ice cap has raised sea levels by 7.2mm, and from Greenland by 10.6mm. Every year, the world’s oceans are 4mm higher than they were the year before.

“Although we anticipated the ice sheets would lose increasing amounts of ice in response to the warming of the oceans and the atmosphere, the rate at which they are melting has accelerated faster than we could have imagined,” said Tom Slater of the University of Leeds, in the UK, who led the research.

“The melting is overtaking the climate models we use to guide us, and we are in danger of being unprepared for the risks posed by sea level rise.”

Dr Slater and his colleagues are the third team to warn in the last month that observations of climate already match the worst-case scenarios dreamed up by forecasters preparing for a range of possible climate outcomes.

Erosion risk rises

The latest reading of glacial melt rates suggests that the risk of storm surges for many of the world’s greatest cities will double by the close of the century. But coastal cities – and the farmers who already work 38% of the terrestrial surface to feed almost 8bn people – have another more immediate problem.

In a warmer world, more water evaporates. In a warmer atmosphere, the capacity of the air to hold moisture also increases, so along with more intense droughts, heavier rainfall is on the way for much of the world. And the heavier the rain, or the more prolonged the drought, the higher the risk of soil erosion.

In 2015 the world’s farmers and foresters watched 43 billion tonnes of topsoil wash away from hillsides or blow away from tilled land and into the sea. By 2070, this burden of silt swept away by water or blown by wind will have risen by between 30% and 66%: probably more than 28 bn tons of additional loss.

This could only impoverish the farmland, according to a study by Swiss scientists in the Proceedings of the National Academy of Sciences. It could also impoverish people, communities and countries. The worst hit could be in the less developed nations of the tropics and subtropics.

But the flow of ever-higher silt levels into ever-rising seas also raises a new hazard: hydrologists call it river avulsion. It’s a simple and natural process. As conditions change, so rivers will naturally change their flow to spill over new floodplains and extend coastal lands.

Survival in question

But river avulsions can also be helped along by rising sea levels. Since 10% of humanity is crowded into rich, fertile delta lands, and since some of the deadliest floods in human history – two in China in 1887 and 1931 claimed six million lives – have been caused by river avulsions, the question becomes a matter of life and death.

US scientists report, also in the Proceedings of the National Academy of Sciences, that rising sea levels alone could make abrupt river avulsion more probable, especially as delta lands could be subsiding, because of groundwater and other extraction.

The dangers of avulsion are affected by the rate of sediment deposit in the river channels, and this is likely to rise with sea levels. This in turn raises the level of the river and eventually a breach of a levee or other flood defence will force the river to find a swifter, steeper path to the sea.

Cities such as New Orleans and the coastal communities of the Mississippi delta are already vulnerable. “Avulsions are the earthquakes of rivers,” said Michael Lamb, of California Institute of Technology, one of the authors.

“They are sudden and sometimes catastrophic natural events that occur with statistical regularity, shifting the direction of major rivers. We are trying to understand where and when the next avulsions will occur.” – Climate News Network

Arctic heating races ahead of worst case estimates

Arctic heating is happening far faster than anybody had anticipated. And the ice record suggests this has happened before.

LONDON, 2 September, 2020 – An international team of scientists brings bad news about Arctic heating: the polar ocean is warming not only faster than anybody predicted, it is getting hotter at a rate faster than even the worst case climate scenario predictions have so far foreseen.

Such dramatic rises in Arctic temperatures have been recorded before, but only during the last Ice Age. Evidence from the Greenland ice cores suggests that temperatures rose by 10°C or even 12°C, over a period of between 40 years and a century, between 120,000 years and 11,000 years ago.

“We have been clearly underestimating the rate of temperature increases in the atmosphere nearest to the sea level, which has ultimately caused sea ice to disappear faster than we had anticipated,” said Jens Hesselbjerg Christensen, a physicist at the University of Copenhagen in Denmark, one of 16 scientists who report in the journal Nature Climate Change on a new analysis of 40 years of data from the Arctic region.

They found that, on average, the Arctic has been warming at the rate of 1°C per decade for the last four decades. Around Norway’s Svalbard archipelago, temperatures rose even faster, at 1.5°C every 10 years.

“We have been clearly underestimating the rate of temperature increases in the atmosphere nearest to the sea level, which has ultimately caused sea ice to disappear faster than we had anticipated”

During the last two centuries, as atmospheric levels of carbon dioxide climbed from an average of around 285 parts per million to more than 400ppm, so the global average temperature of the planet rose: by a fraction more than 1°C.

The latest study is a reminder that temperatures in the Arctic are rising far faster than that. And the news is hardly a shock: within the past few weeks, separate teams of researchers, reporting to other journals, have warned that Greenland – the biggest single reservoir of ice in the northern hemisphere – is melting faster than ever; more alarmingly, its icecap is losing mass at a rate that suggests the loss could become irreversible.

Researchers have also confirmed that the average planetary temperature  continues to rise inexorably, that the Arctic Ocean could be free of ice in  summer as early as 2035, and that the climate scientists’ “worst case” scenarios are no longer to be regarded as a warning of what could happen: the evidence is that what is happening now already matches the climate forecaster’s worst case. The latest finding implicitly and explicitly supports this flurry of ominous observation.

“We have looked at the climate models analysed and assessed by the UN Climate Panel,” said Professor Christensen. “Only those models based on the worst case scenario, with the highest carbon dioxide emissions, come close to what our temperature measurements show over the past 40 years, from 1979 to today.” – Climate News Network

Arctic heating is happening far faster than anybody had anticipated. And the ice record suggests this has happened before.

LONDON, 2 September, 2020 – An international team of scientists brings bad news about Arctic heating: the polar ocean is warming not only faster than anybody predicted, it is getting hotter at a rate faster than even the worst case climate scenario predictions have so far foreseen.

Such dramatic rises in Arctic temperatures have been recorded before, but only during the last Ice Age. Evidence from the Greenland ice cores suggests that temperatures rose by 10°C or even 12°C, over a period of between 40 years and a century, between 120,000 years and 11,000 years ago.

“We have been clearly underestimating the rate of temperature increases in the atmosphere nearest to the sea level, which has ultimately caused sea ice to disappear faster than we had anticipated,” said Jens Hesselbjerg Christensen, a physicist at the University of Copenhagen in Denmark, one of 16 scientists who report in the journal Nature Climate Change on a new analysis of 40 years of data from the Arctic region.

They found that, on average, the Arctic has been warming at the rate of 1°C per decade for the last four decades. Around Norway’s Svalbard archipelago, temperatures rose even faster, at 1.5°C every 10 years.

“We have been clearly underestimating the rate of temperature increases in the atmosphere nearest to the sea level, which has ultimately caused sea ice to disappear faster than we had anticipated”

During the last two centuries, as atmospheric levels of carbon dioxide climbed from an average of around 285 parts per million to more than 400ppm, so the global average temperature of the planet rose: by a fraction more than 1°C.

The latest study is a reminder that temperatures in the Arctic are rising far faster than that. And the news is hardly a shock: within the past few weeks, separate teams of researchers, reporting to other journals, have warned that Greenland – the biggest single reservoir of ice in the northern hemisphere – is melting faster than ever; more alarmingly, its icecap is losing mass at a rate that suggests the loss could become irreversible.

Researchers have also confirmed that the average planetary temperature  continues to rise inexorably, that the Arctic Ocean could be free of ice in  summer as early as 2035, and that the climate scientists’ “worst case” scenarios are no longer to be regarded as a warning of what could happen: the evidence is that what is happening now already matches the climate forecaster’s worst case. The latest finding implicitly and explicitly supports this flurry of ominous observation.

“We have looked at the climate models analysed and assessed by the UN Climate Panel,” said Professor Christensen. “Only those models based on the worst case scenario, with the highest carbon dioxide emissions, come close to what our temperature measurements show over the past 40 years, from 1979 to today.” – Climate News Network

‘Ban adverts for cars that damage the climate’

Tobacco advertisements are often banned these days. So why not ban adverts for gas-guzzling cars that damage the planet?

LONDON, 1 September, 2020 – Many countries now ban adverts for tobacco products and some now limit sales of junk food, to protect public health. All of them have reduced advertising, or ended it outright.

So, campaigners argue, why not do the same with adverts which promote high-carbon products and lifestyles, damaging people’s health and heating the planet?

There’s growing pressure for bans like that in the United Kingdom, with a focus on ending the promotion of highly-polluting cars, gas-guzzling 4x4s, also known as SUVs, an argument developed by a campaign called Badvertising.

The Rapid Transition Alliance (RTA) is a UK-based group which argues that humankind must undertake “widespread behaviour change to sustainable lifestyles … to live within planetary ecological boundaries and to limit global warming to below 1.5°C” (the more stringent limit set by the 2015 Paris Agreement on climate change).

As part of its work to publicise how projects and communities can withstand the effects of climate heating, the Alliance too is supporting Badvertising, which it is convinced can succeed.

40-year resistance

The RTA argues that advertising bans have worked before, provided they have had three factors in their favour: strong evidence from trusted sources; clear campaigning; and a threat to public health, which policymakers take seriously.

Even so, it says, powerful moneyed interests will oppose changes that threaten their income. Advertising is one key way of driving consumption, encouraging us to “shop till we drop”. In 2020 world expenditure on advertising is expected to reach US$691.7 billion (£520bn), up by 7.0% from 2019, despite the Covid-19 pandemic.

That’s more than China’s infrastructure investment programme after the 2008 financial crisis, and over four times more than the $153bn provided to developing countries in 2018 by the 30 members of the OECD’s development assistance committee.

With tobacco, once its huge public health impact became clear – 100 million people died in the last century from its use, and the figure for this century is expected to be ten times greater – campaigners had to work tirelessly for another 40 years until its promotion was banned.

The tobacco industry meanwhile resisted fiercely, arguing, for example, that adverts didn’t increase smoking but merely encouraged people to switch brands, despite evidence to the contrary.

“Those who manipulate the unseen mechanism of society constitute an invisible government which is the true ruling power”

For climate and health campaigners today there are valuable lessons to be learned from the fight against tobacco, the RTA says. Both tobacco smoke and car exhausts contain similar toxins that directly threaten human health.

Underlying health conditions mean that poorer households are worse hit than richer ones by the effects of tobacco and air pollution from vehicles, and so are more vulnerable too to health crises like Covid-19.

Junk food is another target for campaigners against advertising, particularly where child obesity is an issue. In London a ban on unhealthy food advertising was introduced in 2018, to widespread public approval. The UK government is now set to implement stricter rules on how junk food is advertised and sold across the country.

This year the Mexican state of Oaxaca banned the sale of sugary drinks and high-calorie snack foods to children. Mexicans drink 163 litres of soft drinks a year per head – the world’s highest level – and they start young. About 73% of Mexicans are considered overweight, and related diseases such as diabetes are rife.

A survey by El Poder del Consumidor (in Spanish) – a Mexican consumer advocacy group and drinks industry critic – found 70% of schoolchildren in a poor region of Guerrero state reported having soft drinks for breakfast. “When you go to these communities, what you find is junk food. There’s no access to clean drinking water,” said Alejandro Calvillo, the group’s director.

Doubt-spreading

In 2006 a US district judge ruled that tobacco companies had “devised and executed a scheme to defraud consumers … about the hazards of cigarettes, hazards that their own internal company documents proved they had known about since the 1950s.” After four decades of delay, obfuscation and the spreading of doubt by the industry, the tobacco companies were found guilty.

In the UK the first calls to restrict advertising came in 1962 from the Royal College of Physicians. The general advertising of tobacco products was banned in stages from 2003. But concern at the damage that advertising can cause continues.

Communities in the UK city of Bristol recently acted against the bright LCD billboards which have proliferated there, causing light pollution and using huge amounts of energy to adverise a range of goods and services. A Bristol initiative to help residents object to planning applications for new digital advertising screens has now led to a wider network, Adfree Cities.

Advertising is part of the broader public relations industry. The RTA quotes an American citizen, often called the father of public relations, Edward Bernays, who worked for the US Committee on Public Information, a body for official propaganda during the first world war.

Bernays once wrote: “Those who manipulate the unseen mechanism of society constitute an invisible government which is the true ruling power. We are governed, our minds moulded, our tastes formed, our ideas suggested largely by men we have never heard of.”

Doctors’ crucial intervention

One turning point in the battle against tobacco industry propaganda in the UK, the RTA says, was the involvement of the doctors’ trades union, the British Medical Association (BMA). This brought the people the public trusted most – their family doctors – into direct confrontation with the tobacco industry.

But the medical profession was to play another crucial part in protecting public health on a far wider front in 2017, when an article in the Lancet, the leading British medical journal, featured a major study, this time with evidence supporting the climatologists’ findings that climate change is a growing health hazard.

In response, Simon Dalby of Wilfrid Laurier University in Canada asks why we don’t use advertising restrictions for climate change in the same way that we have with other public health hazards like smoking.

Hundreds of millions of people around the world are already suffering because of climate change, he points out. Infectious diseases are spreading faster as the climate heats, hunger and malnutrition are worsening, allergy seasons are getting longer, and sometimes it’s simply too hot for farmers to tend their crops.

Professor Dalby’s suggestion? Not only should we restrict adverts for gas-guzzlers. We should treat climate change itself, not as an environmental problem, but as a health emergency. – Climate News Network

* * * * * * *

The Rapid Transition Alliance is coordinated by the New Weather Institute, the STEPS Centre at the Institute of  Development Studies, and the School of Global Studies at the University of Sussex, UK. The Climate News Network is partnering with and supported by the Rapid Transition Alliance, and will be reporting regularly on its work. If you would like to see more stories of evidence-based hope for rapid transition, please sign up here.

Do you know a story of rapid transition? If so, we’d like to hear from you. Please send us a brief outline on info@climatenewsnetwork.net. Thank you.

Tobacco advertisements are often banned these days. So why not ban adverts for gas-guzzling cars that damage the planet?

LONDON, 1 September, 2020 – Many countries now ban adverts for tobacco products and some now limit sales of junk food, to protect public health. All of them have reduced advertising, or ended it outright.

So, campaigners argue, why not do the same with adverts which promote high-carbon products and lifestyles, damaging people’s health and heating the planet?

There’s growing pressure for bans like that in the United Kingdom, with a focus on ending the promotion of highly-polluting cars, gas-guzzling 4x4s, also known as SUVs, an argument developed by a campaign called Badvertising.

The Rapid Transition Alliance (RTA) is a UK-based group which argues that humankind must undertake “widespread behaviour change to sustainable lifestyles … to live within planetary ecological boundaries and to limit global warming to below 1.5°C” (the more stringent limit set by the 2015 Paris Agreement on climate change).

As part of its work to publicise how projects and communities can withstand the effects of climate heating, the Alliance too is supporting Badvertising, which it is convinced can succeed.

40-year resistance

The RTA argues that advertising bans have worked before, provided they have had three factors in their favour: strong evidence from trusted sources; clear campaigning; and a threat to public health, which policymakers take seriously.

Even so, it says, powerful moneyed interests will oppose changes that threaten their income. Advertising is one key way of driving consumption, encouraging us to “shop till we drop”. In 2020 world expenditure on advertising is expected to reach US$691.7 billion (£520bn), up by 7.0% from 2019, despite the Covid-19 pandemic.

That’s more than China’s infrastructure investment programme after the 2008 financial crisis, and over four times more than the $153bn provided to developing countries in 2018 by the 30 members of the OECD’s development assistance committee.

With tobacco, once its huge public health impact became clear – 100 million people died in the last century from its use, and the figure for this century is expected to be ten times greater – campaigners had to work tirelessly for another 40 years until its promotion was banned.

The tobacco industry meanwhile resisted fiercely, arguing, for example, that adverts didn’t increase smoking but merely encouraged people to switch brands, despite evidence to the contrary.

“Those who manipulate the unseen mechanism of society constitute an invisible government which is the true ruling power”

For climate and health campaigners today there are valuable lessons to be learned from the fight against tobacco, the RTA says. Both tobacco smoke and car exhausts contain similar toxins that directly threaten human health.

Underlying health conditions mean that poorer households are worse hit than richer ones by the effects of tobacco and air pollution from vehicles, and so are more vulnerable too to health crises like Covid-19.

Junk food is another target for campaigners against advertising, particularly where child obesity is an issue. In London a ban on unhealthy food advertising was introduced in 2018, to widespread public approval. The UK government is now set to implement stricter rules on how junk food is advertised and sold across the country.

This year the Mexican state of Oaxaca banned the sale of sugary drinks and high-calorie snack foods to children. Mexicans drink 163 litres of soft drinks a year per head – the world’s highest level – and they start young. About 73% of Mexicans are considered overweight, and related diseases such as diabetes are rife.

A survey by El Poder del Consumidor (in Spanish) – a Mexican consumer advocacy group and drinks industry critic – found 70% of schoolchildren in a poor region of Guerrero state reported having soft drinks for breakfast. “When you go to these communities, what you find is junk food. There’s no access to clean drinking water,” said Alejandro Calvillo, the group’s director.

Doubt-spreading

In 2006 a US district judge ruled that tobacco companies had “devised and executed a scheme to defraud consumers … about the hazards of cigarettes, hazards that their own internal company documents proved they had known about since the 1950s.” After four decades of delay, obfuscation and the spreading of doubt by the industry, the tobacco companies were found guilty.

In the UK the first calls to restrict advertising came in 1962 from the Royal College of Physicians. The general advertising of tobacco products was banned in stages from 2003. But concern at the damage that advertising can cause continues.

Communities in the UK city of Bristol recently acted against the bright LCD billboards which have proliferated there, causing light pollution and using huge amounts of energy to adverise a range of goods and services. A Bristol initiative to help residents object to planning applications for new digital advertising screens has now led to a wider network, Adfree Cities.

Advertising is part of the broader public relations industry. The RTA quotes an American citizen, often called the father of public relations, Edward Bernays, who worked for the US Committee on Public Information, a body for official propaganda during the first world war.

Bernays once wrote: “Those who manipulate the unseen mechanism of society constitute an invisible government which is the true ruling power. We are governed, our minds moulded, our tastes formed, our ideas suggested largely by men we have never heard of.”

Doctors’ crucial intervention

One turning point in the battle against tobacco industry propaganda in the UK, the RTA says, was the involvement of the doctors’ trades union, the British Medical Association (BMA). This brought the people the public trusted most – their family doctors – into direct confrontation with the tobacco industry.

But the medical profession was to play another crucial part in protecting public health on a far wider front in 2017, when an article in the Lancet, the leading British medical journal, featured a major study, this time with evidence supporting the climatologists’ findings that climate change is a growing health hazard.

In response, Simon Dalby of Wilfrid Laurier University in Canada asks why we don’t use advertising restrictions for climate change in the same way that we have with other public health hazards like smoking.

Hundreds of millions of people around the world are already suffering because of climate change, he points out. Infectious diseases are spreading faster as the climate heats, hunger and malnutrition are worsening, allergy seasons are getting longer, and sometimes it’s simply too hot for farmers to tend their crops.

Professor Dalby’s suggestion? Not only should we restrict adverts for gas-guzzlers. We should treat climate change itself, not as an environmental problem, but as a health emergency. – Climate News Network

* * * * * * *

The Rapid Transition Alliance is coordinated by the New Weather Institute, the STEPS Centre at the Institute of  Development Studies, and the School of Global Studies at the University of Sussex, UK. The Climate News Network is partnering with and supported by the Rapid Transition Alliance, and will be reporting regularly on its work. If you would like to see more stories of evidence-based hope for rapid transition, please sign up here.

Do you know a story of rapid transition? If so, we’d like to hear from you. Please send us a brief outline on info@climatenewsnetwork.net. Thank you.

Plant world feels effect of growing climate heat

From Hudson Bay to Tierra del Fuego, the plant world is beginning to change. Blame it on global heating.

LONDON, 28 August, 2020 – From one end of the Americas to the other, climate heating is subjecting the plant world to radical change, with cold-resistant species increasingly yielding place to those that welcome the rising warmth.

That badge of Canadian identity, the sugar maple, may one day turn sour. As global temperatures, driven by profligate human use of fossil fuels, continue to soar, Acer saccharum could simply lose its habitat and no longer sweeten the forests from Novia Scotia to the Appalachians.

And the southern live oak, so associated with Florida that a city there preserves its name, may find life too hot for comfort: in the south of the state, Quercus virginiana could one day be replaced by trees from the Caribbean or even further south, such as the already present Cuban mahogany Swietenia mahogani or the Gumbo limbo Bursera simaruba.

And in what was once the reliably wintry city of New York, that marvel of old Mississippi the southern magnolia, Magnolia grandiflora, has begun to multiply and bloom ever earlier each year.

These species shifts are just part of a larger trend in the Americas, from Hudson Bay to Tierra del Fuego, according to new research in the journal Nature Climate Change.

“If we lose some plants, we may also lose the insects, birds and many other forms of wildlife that are critical to our ways of life”

Researchers analysed 60 million records of 17,000 plant species in almost 200 New World eco-regions, from 1970 to 2011, to identify a pattern of change in response to heat: a phenomenon called thermophilisation.

“Almost anywhere you go, the types of species that you encounter now are different than what you would have found in the same spot 40 years ago, and we believe that this pattern is the direct result of rising temperatures and climate change,” said Ken Feeley, a biologist at the University of Miami, who led the research.

The study – two continents, and a range of temperature regimes from near-Arctic to equatorial and onwards, almost to the edge of the Southern Ocean – confirms the big picture, but dozens of earlier studies had already built up a mosaic of observations that told much the same story.

As temperatures rise, and precipitation patterns shift, plants respond. The forests of the northern hemisphere everywhere are vulnerable to heat and drought, and even species considered resistant to drought could be about to succumb.

In the lowland tropics, researchers have warned that conditions could become so intemperate that some species may fail to germinate and renew their tenure in the forest. Researchers have observed tropical species moving uphill to find more equable temperature regimes, while others have warned that those upland species that are comfortable at height may soon find it so hot there could be nowhere left to go.

Worldwide effects

The northern tundra is already beginning to host new plant life, but rising temperatures and shifting climate regimes could also damage forests and fuel even more global warming.

The latest study shows once again that, in any ecosystem, those species that are more likely to cope with colder temperatures are being replaced by others that just like it hot.

“Some of these changes can be so dramatic that we are shifting entire habitat types from forests to grasslands or vice versa – by looking at all types of plants over long periods of time and over huge areas, we were able to observe those changes,” said Professor Feeley.

“All animals – including humans – depend on the plants around them. If we lose some plants, we may also lose the insects, birds and many other forms of wildlife that we are used to seeing in our communities and that are critical to our ways of life.

“When people think of climate change, they need to realise that it’s not just about losing ice in Antarctica, or rising sea levels – climate change affects almost every natural system in every part of the planet.” – Climate News Network

From Hudson Bay to Tierra del Fuego, the plant world is beginning to change. Blame it on global heating.

LONDON, 28 August, 2020 – From one end of the Americas to the other, climate heating is subjecting the plant world to radical change, with cold-resistant species increasingly yielding place to those that welcome the rising warmth.

That badge of Canadian identity, the sugar maple, may one day turn sour. As global temperatures, driven by profligate human use of fossil fuels, continue to soar, Acer saccharum could simply lose its habitat and no longer sweeten the forests from Novia Scotia to the Appalachians.

And the southern live oak, so associated with Florida that a city there preserves its name, may find life too hot for comfort: in the south of the state, Quercus virginiana could one day be replaced by trees from the Caribbean or even further south, such as the already present Cuban mahogany Swietenia mahogani or the Gumbo limbo Bursera simaruba.

And in what was once the reliably wintry city of New York, that marvel of old Mississippi the southern magnolia, Magnolia grandiflora, has begun to multiply and bloom ever earlier each year.

These species shifts are just part of a larger trend in the Americas, from Hudson Bay to Tierra del Fuego, according to new research in the journal Nature Climate Change.

“If we lose some plants, we may also lose the insects, birds and many other forms of wildlife that are critical to our ways of life”

Researchers analysed 60 million records of 17,000 plant species in almost 200 New World eco-regions, from 1970 to 2011, to identify a pattern of change in response to heat: a phenomenon called thermophilisation.

“Almost anywhere you go, the types of species that you encounter now are different than what you would have found in the same spot 40 years ago, and we believe that this pattern is the direct result of rising temperatures and climate change,” said Ken Feeley, a biologist at the University of Miami, who led the research.

The study – two continents, and a range of temperature regimes from near-Arctic to equatorial and onwards, almost to the edge of the Southern Ocean – confirms the big picture, but dozens of earlier studies had already built up a mosaic of observations that told much the same story.

As temperatures rise, and precipitation patterns shift, plants respond. The forests of the northern hemisphere everywhere are vulnerable to heat and drought, and even species considered resistant to drought could be about to succumb.

In the lowland tropics, researchers have warned that conditions could become so intemperate that some species may fail to germinate and renew their tenure in the forest. Researchers have observed tropical species moving uphill to find more equable temperature regimes, while others have warned that those upland species that are comfortable at height may soon find it so hot there could be nowhere left to go.

Worldwide effects

The northern tundra is already beginning to host new plant life, but rising temperatures and shifting climate regimes could also damage forests and fuel even more global warming.

The latest study shows once again that, in any ecosystem, those species that are more likely to cope with colder temperatures are being replaced by others that just like it hot.

“Some of these changes can be so dramatic that we are shifting entire habitat types from forests to grasslands or vice versa – by looking at all types of plants over long periods of time and over huge areas, we were able to observe those changes,” said Professor Feeley.

“All animals – including humans – depend on the plants around them. If we lose some plants, we may also lose the insects, birds and many other forms of wildlife that we are used to seeing in our communities and that are critical to our ways of life.

“When people think of climate change, they need to realise that it’s not just about losing ice in Antarctica, or rising sea levels – climate change affects almost every natural system in every part of the planet.” – Climate News Network

Hotter oceans make the tropics expand polewards

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

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

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

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

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

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

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

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

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

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

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

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

Clear link

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Clear link

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

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

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

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

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

Changing oceans reveal clear human thumbprint

Climate heating must have already begun to result in changing oceans. The next step is to confirm and monitor this change.

LONDON, 26 August, 2020 – Humankind has already begun to reshape the biggest available living space on the planet and to leave its mark in the changing oceans.

New research suggests that somewhere between 20% and 55% of the Atlantic, Pacific and Indian Oceans now have temperatures and salt levels that should be measurably different because of climate change driven by profligate human combustion of fossil fuels.

And forecasts suggest that by mid-century the scale of human impact will only have increased – to between 40% and 60%. By 2080, human impact on the oceans will have begun to change between 55% and 80% of the blue planet.

Although the researchers – they report in the journal Nature Climate Change – have based their predictions on computer models, they are confident that the thumbprint of human-induced climate change began to leave its mark on the seas of the Southern Hemisphere as long ago as the 1980s.

“We have been detecting ocean temperature change at the surface due to climate change for several decades now,” said Eric Guilyardi, of the University of Reading in the UK and the Laboratory of Oceanography and Climate in Paris, France.

“Our results highlight the importance of maintaining and augmenting an ocean observing system capable of detecting and monitoring persistent anthropogenic changes”

“But changes in vast areas of the ocean, particularly deeper parts, are much more challenging to detect.”

The problem of measurement is simple: the ocean is enormous. It covers 70% of the planet to an average depth of 3.7 kms. It defines the planet.

It is almost certainly where life on Earth first emerged; it was life’s only home for the first three billion years.

And it is in a state of constant change, constantly evaporating, and continually replenished with freshwater from rainfall, river flow and melting polar ice. So temperature and salinity change naturally, and with the seasons, and with much longer cyclic swings driven by the atmosphere.

Scientists have been measuring surface conditions for many decades. The ocean at depth is a bit more of a challenge. The question the researchers put was a simple one: could temperature and salinity levels in parts of the ocean have risen or fallen higher or lower than they would in normal peaks and troughs?

Beyond natural variability

It’s not an easy question: oceanography is expensive, the ocean is huge, much of it has never been studied and the ways in which the ocean layers mix is still a bit of a puzzle.

So the scientists started with two models, with and without the impact of human action. They then worked on an analysis of salt levels and temperatures to detect significant change, and then tried to predict the dates at which this change ought to declare itself.

Their readings tell them that changes beyond natural variability in the northern hemisphere – all the seas from the Arctic Ocean to the equatorial waters – could have emerged between 2010 and 2030. That is, change is already happening.

Their simulations also predicted that whatever shifts occurred at depth in the temperature and chemistry of the southern oceans, these could have been identified up to 40 years ago, had researchers had the technology, the funding, the people and the ships and submersibles to do so.

“Our results highlight the importance of maintaining and augmenting an ocean observing system capable of detecting and monitoring persistent anthropogenic changes,” they report. – Climate News Network

Climate heating must have already begun to result in changing oceans. The next step is to confirm and monitor this change.

LONDON, 26 August, 2020 – Humankind has already begun to reshape the biggest available living space on the planet and to leave its mark in the changing oceans.

New research suggests that somewhere between 20% and 55% of the Atlantic, Pacific and Indian Oceans now have temperatures and salt levels that should be measurably different because of climate change driven by profligate human combustion of fossil fuels.

And forecasts suggest that by mid-century the scale of human impact will only have increased – to between 40% and 60%. By 2080, human impact on the oceans will have begun to change between 55% and 80% of the blue planet.

Although the researchers – they report in the journal Nature Climate Change – have based their predictions on computer models, they are confident that the thumbprint of human-induced climate change began to leave its mark on the seas of the Southern Hemisphere as long ago as the 1980s.

“We have been detecting ocean temperature change at the surface due to climate change for several decades now,” said Eric Guilyardi, of the University of Reading in the UK and the Laboratory of Oceanography and Climate in Paris, France.

“Our results highlight the importance of maintaining and augmenting an ocean observing system capable of detecting and monitoring persistent anthropogenic changes”

“But changes in vast areas of the ocean, particularly deeper parts, are much more challenging to detect.”

The problem of measurement is simple: the ocean is enormous. It covers 70% of the planet to an average depth of 3.7 kms. It defines the planet.

It is almost certainly where life on Earth first emerged; it was life’s only home for the first three billion years.

And it is in a state of constant change, constantly evaporating, and continually replenished with freshwater from rainfall, river flow and melting polar ice. So temperature and salinity change naturally, and with the seasons, and with much longer cyclic swings driven by the atmosphere.

Scientists have been measuring surface conditions for many decades. The ocean at depth is a bit more of a challenge. The question the researchers put was a simple one: could temperature and salinity levels in parts of the ocean have risen or fallen higher or lower than they would in normal peaks and troughs?

Beyond natural variability

It’s not an easy question: oceanography is expensive, the ocean is huge, much of it has never been studied and the ways in which the ocean layers mix is still a bit of a puzzle.

So the scientists started with two models, with and without the impact of human action. They then worked on an analysis of salt levels and temperatures to detect significant change, and then tried to predict the dates at which this change ought to declare itself.

Their readings tell them that changes beyond natural variability in the northern hemisphere – all the seas from the Arctic Ocean to the equatorial waters – could have emerged between 2010 and 2030. That is, change is already happening.

Their simulations also predicted that whatever shifts occurred at depth in the temperature and chemistry of the southern oceans, these could have been identified up to 40 years ago, had researchers had the technology, the funding, the people and the ships and submersibles to do so.

“Our results highlight the importance of maintaining and augmenting an ocean observing system capable of detecting and monitoring persistent anthropogenic changes,” they report. – Climate News Network

Batteries boost Californian hopes of cooler future

Californian hopes of cooler future rise as the world’s biggest battery storage system comes on stream.

LONDON, 25 August, 2020 – Recent reports of record-breaking heat in the Golden State may be only part of the story: Californian hopes of cooler future days are strengthening with the entry into service of new technology that should promise a less torrid future for millions of people.

The ability to store large amounts of renewable energy – generated mainly by solar and wind power – is seen as a key component in the battle to combat catastrophic climate change.

The Gateway Energy Storage project, near San Diego in southern California, is capable of storing and redistributing up to 230MW of power from solar installations in the area.

“By charging during solar production on off-peak hours and delivering energy to the grid during times of peak demand for power, our battery storage projects improve electric reliability, reduce costs and help our state meet its climate objectives”, said John King of LS Power, the New York-based power development company operating the project.

“The hots are getting hotter, the drys are getting drier. Climate change is real”

California – the most populous state in the US and one of the wealthiest – has been hit by a series of power blackouts in recent weeks as an extreme heatwave has led to increased air conditioner use and expanding energy demand.

In the Central Valley area of the state, one of the most productive agricultural regions in the world, daytime temperatures have soared to more than 40°C.

In mid-August the temperature in Death Valley, a desert area in southern California, reached 54°C – which could be the highest temperature reliably recorded anywhere in the world.

Further north, residents of Sacramento, the state capital, baked as temperatures reached over 40°C on consecutive days – more than 7°C above normal for the time of year.

Though it’s too early to say whether the heatwave is due to increased levels of climate-changing greenhouse gases in the Earth’s atmosphere, Gavin Newsom, California’s governor, is in little doubt about what is driving the heat extremes.

World’s worst air

“The hots are getting hotter, the drys are getting drier”, Newsom said in a video message to delegates participating in a virtual convention of the Democratic Party. “Climate change is real. If you are in denial about climate change, come to California”, said Newsom.

The extreme heat has led to increased storm activity in many areas of the state and a series of lightning strikes which, in turn, have caused an outbreak of wildfires.

Several people have been killed as the fires have raged out of control over hundreds of thousands of acres. Air quality in some regions has declined to levels not seen before.

At one stage this month the area around San Francisco – one of the globe’s wealthiest cities and home to many of the biggest IT companies – was described as having the worst air quality in the world.

Batteries in demand

A shortage of equipment and firefighters has added to problems. In the past California has used prisoners to help fight fires – a policy condemned by various groups.

Many of the prisoners who might have been used for this purpose are no longer available: they’ve either been placed in quarantine or released in an attempt to control the spread of the Covid virus through California’s overcrowded prison system.

Developing more battery storage to service fast-growing solar and wind industries is seen as vital for the state’s energy needs.

California is facing restrictions on importing power from other states in the western US due to heatwaves in those regions and rising power demand. It has also been shutting down fossil fuel-burning power plants.

Governor Newsom said this month that state utilities must find solutions to the power problem: blackouts, he said, were “unacceptable and unbefitting of the nation’s largest and most innovative state.” – Climate News Network

Californian hopes of cooler future rise as the world’s biggest battery storage system comes on stream.

LONDON, 25 August, 2020 – Recent reports of record-breaking heat in the Golden State may be only part of the story: Californian hopes of cooler future days are strengthening with the entry into service of new technology that should promise a less torrid future for millions of people.

The ability to store large amounts of renewable energy – generated mainly by solar and wind power – is seen as a key component in the battle to combat catastrophic climate change.

The Gateway Energy Storage project, near San Diego in southern California, is capable of storing and redistributing up to 230MW of power from solar installations in the area.

“By charging during solar production on off-peak hours and delivering energy to the grid during times of peak demand for power, our battery storage projects improve electric reliability, reduce costs and help our state meet its climate objectives”, said John King of LS Power, the New York-based power development company operating the project.

“The hots are getting hotter, the drys are getting drier. Climate change is real”

California – the most populous state in the US and one of the wealthiest – has been hit by a series of power blackouts in recent weeks as an extreme heatwave has led to increased air conditioner use and expanding energy demand.

In the Central Valley area of the state, one of the most productive agricultural regions in the world, daytime temperatures have soared to more than 40°C.

In mid-August the temperature in Death Valley, a desert area in southern California, reached 54°C – which could be the highest temperature reliably recorded anywhere in the world.

Further north, residents of Sacramento, the state capital, baked as temperatures reached over 40°C on consecutive days – more than 7°C above normal for the time of year.

Though it’s too early to say whether the heatwave is due to increased levels of climate-changing greenhouse gases in the Earth’s atmosphere, Gavin Newsom, California’s governor, is in little doubt about what is driving the heat extremes.

World’s worst air

“The hots are getting hotter, the drys are getting drier”, Newsom said in a video message to delegates participating in a virtual convention of the Democratic Party. “Climate change is real. If you are in denial about climate change, come to California”, said Newsom.

The extreme heat has led to increased storm activity in many areas of the state and a series of lightning strikes which, in turn, have caused an outbreak of wildfires.

Several people have been killed as the fires have raged out of control over hundreds of thousands of acres. Air quality in some regions has declined to levels not seen before.

At one stage this month the area around San Francisco – one of the globe’s wealthiest cities and home to many of the biggest IT companies – was described as having the worst air quality in the world.

Batteries in demand

A shortage of equipment and firefighters has added to problems. In the past California has used prisoners to help fight fires – a policy condemned by various groups.

Many of the prisoners who might have been used for this purpose are no longer available: they’ve either been placed in quarantine or released in an attempt to control the spread of the Covid virus through California’s overcrowded prison system.

Developing more battery storage to service fast-growing solar and wind industries is seen as vital for the state’s energy needs.

California is facing restrictions on importing power from other states in the western US due to heatwaves in those regions and rising power demand. It has also been shutting down fossil fuel-burning power plants.

Governor Newsom said this month that state utilities must find solutions to the power problem: blackouts, he said, were “unacceptable and unbefitting of the nation’s largest and most innovative state.” – Climate News Network