Tag Archives: South America

Human activity alters Earth’s spin on its axis

The planet may not catch fire, but climate change really has altered the Earth’s spin on its axis as it rounds the sun.

LONDON, 29 April, 2021 − Human action has altered Earth’s spin on its axis. Climate change since 1990 has altered both the rate and the direction of the drift of the north and south poles.

Chinese researchers report in the journal Geophysical Research Letters that on the basis of their calculations, the dramatic melting of the Antarctic and Greenland ice caps and the Andean glaciers of South America has shifted the weight of the global water storage system and affected the planetary drift of the poles.

This glacial loss has been compounded by massive increases in the use of groundwater − most of the planet’s fresh water is in fact stored in subterranean aquifers − which have helped to accelerate the rate of change.

It sounds like the plot of a science fiction film. It was in fact the plot of a British 1961 science fiction film, The Day the Earth Caught Fire. In that fantasia, Cold War superpower nuclear tests unintentionally alter the planet’s axis of rotation and trigger dramatic changes in climate.

In fact, in the real-life, here-and-now version of planetary rotational shift, climate change driven by economic growth powered by profligate fossil fuel use is the cause. And the superpowers have yet to decide upon a course correction.

Polar speed-up

There is a second difference: the axis of the rotational poles has always shifted, from year to year, in response to the distribution of ice and groundwater, and the oceanic currents; and from aeon to aeon in response to the movements of the continents, and the sloshing of molten iron at the Earth’s core.

What has happened since 1990 is that water loss from both the glaciated land surface and the soil beneath the inhabited surface has been so pronounced that it has tilted the North Pole away from Canada and towards Russia, and accelerated the rate at which this is happening.

Since 1990, geographic North has been tilting, in geodetic language, towards longitude 26°E at the rate of 3.28 milliseconds of arc per year. One millisecond of arc is about 3 cms.

The story has been pieced together by data from a US-German satellite system known as GRACE (short for Gravity Recovery and Climate Experiment), which has been recording ice loss and water storage for most of this century.

“The faster ice-melting under global warming was the most likely cause of the directional change of the polar drift in the 1990s”

The researchers, from the Chinese Academy of Sciences, already had access to 176 years of precision measurement of the polar axial shift. In fact, the loss of ice from both the north and south polar regions has been colossal, and has been happening at speed.

Groundwater, too, has been abstracted at accelerating rates and the study notes that while in 1989 India pumped 194 billion cubic metres from the soil, by 2010 this had reached 351 billion cubic metres. There had, too, been dramatic changes in the water levels of vast inland lakes such as the Aral Sea.

The planet is always in a state of change: the magnetic poles are on the move and scientists have confirmed that climate over very long periods is affected by changes in planetary orbit.

Other teams of researchers had separately confirmed that climate change − and the redistribution of water around the planet − must have altered the length of the day by millionths of a second in the course of a year. But the new research has established something more immediately measurable: the alteration of the pattern of rotational tilt.

“The faster ice-melting under global warming was the most likely cause of the directional change of the polar drift in the 1990s,” the researchers conclude. − Climate News Network

The planet may not catch fire, but climate change really has altered the Earth’s spin on its axis as it rounds the sun.

LONDON, 29 April, 2021 − Human action has altered Earth’s spin on its axis. Climate change since 1990 has altered both the rate and the direction of the drift of the north and south poles.

Chinese researchers report in the journal Geophysical Research Letters that on the basis of their calculations, the dramatic melting of the Antarctic and Greenland ice caps and the Andean glaciers of South America has shifted the weight of the global water storage system and affected the planetary drift of the poles.

This glacial loss has been compounded by massive increases in the use of groundwater − most of the planet’s fresh water is in fact stored in subterranean aquifers − which have helped to accelerate the rate of change.

It sounds like the plot of a science fiction film. It was in fact the plot of a British 1961 science fiction film, The Day the Earth Caught Fire. In that fantasia, Cold War superpower nuclear tests unintentionally alter the planet’s axis of rotation and trigger dramatic changes in climate.

In fact, in the real-life, here-and-now version of planetary rotational shift, climate change driven by economic growth powered by profligate fossil fuel use is the cause. And the superpowers have yet to decide upon a course correction.

Polar speed-up

There is a second difference: the axis of the rotational poles has always shifted, from year to year, in response to the distribution of ice and groundwater, and the oceanic currents; and from aeon to aeon in response to the movements of the continents, and the sloshing of molten iron at the Earth’s core.

What has happened since 1990 is that water loss from both the glaciated land surface and the soil beneath the inhabited surface has been so pronounced that it has tilted the North Pole away from Canada and towards Russia, and accelerated the rate at which this is happening.

Since 1990, geographic North has been tilting, in geodetic language, towards longitude 26°E at the rate of 3.28 milliseconds of arc per year. One millisecond of arc is about 3 cms.

The story has been pieced together by data from a US-German satellite system known as GRACE (short for Gravity Recovery and Climate Experiment), which has been recording ice loss and water storage for most of this century.

“The faster ice-melting under global warming was the most likely cause of the directional change of the polar drift in the 1990s”

The researchers, from the Chinese Academy of Sciences, already had access to 176 years of precision measurement of the polar axial shift. In fact, the loss of ice from both the north and south polar regions has been colossal, and has been happening at speed.

Groundwater, too, has been abstracted at accelerating rates and the study notes that while in 1989 India pumped 194 billion cubic metres from the soil, by 2010 this had reached 351 billion cubic metres. There had, too, been dramatic changes in the water levels of vast inland lakes such as the Aral Sea.

The planet is always in a state of change: the magnetic poles are on the move and scientists have confirmed that climate over very long periods is affected by changes in planetary orbit.

Other teams of researchers had separately confirmed that climate change − and the redistribution of water around the planet − must have altered the length of the day by millionths of a second in the course of a year. But the new research has established something more immediately measurable: the alteration of the pattern of rotational tilt.

“The faster ice-melting under global warming was the most likely cause of the directional change of the polar drift in the 1990s,” the researchers conclude. − Climate News Network

Rich world’s demands fell poorer world’s forests

The tropical forests maintain global climate and nurture the riches of nature. The rich world’s demands are destroying them.

LONDON, 9 April, 2021 − The world’s great ecosystems − moderators of climate, nurseries for evolution − are still being destroyed in the service of global trade, to meet the rich world’s demands. Once again, researchers have confirmed that the wealthy nations are in effect ploughing savanna and felling tropical forests at a distance.

In the first 15 years of this century, the growing demand from the well-heeled for chocolate, rubber, cotton, soy, beef and exotic timber has meant that poorer nations have actually increased their levels of deforestation.

In effect, every human in the G7 nations − Canada, France, Germany, Italy, Japan, the UK and the US − is responsible for the loss of at least four trees a year, mostly in the developing world.

And in a separate study in another journal, another team of scientists has examined satellite data to confirm that between 1985 and 2018, humans cleared or altered 268 million hectares of natural ecosystem on the continent of South America. This is 2.68 million sq kilometres: an area almost the size of Argentina.

Two scientists in Japan report in Nature Ecology and Evolution that they matched levels of deforestation against trade with the world’s biggest economies, to find a clear correlation. They could even distinguish demand in one rich country and its impact on the forests of a poorer nation.

“Richer countries are encouraging deforestation through demand for commodities”

“While cocoa consumption in Germany poses the highest risk to the forests in Côte d’Ivoire and Ghana, deforestation in coastal Tanzania is dominated by Japanese consumers for some agricultural commodities, such as cotton and sesame seed,” they write.

“China shares the most significant responsibility for deforestation in Indochina − particularly in northern Laos for timber and rubber.”

Ironically, many of the richer nations have expanded the areas of forest on their own soil. More than 90% of the deforestation caused by five of the G7 nations was beyond their own borders. In effect, the rich were exporting the destruction of the natural world, and the cost to the planet was disproportionate. The loss of three trees in the Amazon might be more damaging than the loss of 14 trees in Norway, the scientists argue.

“Most forests are in poorer countries who are overwhelmed with economic incentives to cut them down. Our findings show that richer countries are encouraging deforestation through demand for commodities,” said Keiichiro Kanemoto of the Research Institute for Humanity and Nature in Kyoto.

“Policies that aim to preserve forests need to also alleviate poverty. With the coronavirus pandemic, unemployment poses more challenges to forest conservation in developing countries. We want our data to assist in the policy making.”

South American losses

And in the journal Science Advances, a team from the University of Maryland reports on a closer look at the impact of demand for pulpwood, sugar cane, beef, corn and other commodities on one continent: South America, home to some of the world’s most important ecosystems.

They found that human impact on the continent’s land surface just between the years 1985 and 2018 had expanded by 60%. In those years the natural tree cover had dwindled by 16%, and the scale of pasture increased by 23%, cropland by 160% and plantation by 288%.

The sum of all the altered land reached 268 million hectares, or 2.68m sq kms. Argentina, which coincidentally covers 2.73m sq kms, saw an increase of only 23% in human conversion of land use. Brazil tipped the scales with an expansion of 65% in those years.

And, say the researchers, of all this altered land cover on the continent, around 55 million hectares had been degraded − that is, it was no longer functioning as an ecosystem − while being employed for no commercial return. This is the equivalent of more than half a million square kilometres: an area slightly bigger than France.

“No region on Earth is likely to have experienced the scale of land conversion for the sake of agricultural commodity production that South America has,” the authors write. − Climate News Network

The tropical forests maintain global climate and nurture the riches of nature. The rich world’s demands are destroying them.

LONDON, 9 April, 2021 − The world’s great ecosystems − moderators of climate, nurseries for evolution − are still being destroyed in the service of global trade, to meet the rich world’s demands. Once again, researchers have confirmed that the wealthy nations are in effect ploughing savanna and felling tropical forests at a distance.

In the first 15 years of this century, the growing demand from the well-heeled for chocolate, rubber, cotton, soy, beef and exotic timber has meant that poorer nations have actually increased their levels of deforestation.

In effect, every human in the G7 nations − Canada, France, Germany, Italy, Japan, the UK and the US − is responsible for the loss of at least four trees a year, mostly in the developing world.

And in a separate study in another journal, another team of scientists has examined satellite data to confirm that between 1985 and 2018, humans cleared or altered 268 million hectares of natural ecosystem on the continent of South America. This is 2.68 million sq kilometres: an area almost the size of Argentina.

Two scientists in Japan report in Nature Ecology and Evolution that they matched levels of deforestation against trade with the world’s biggest economies, to find a clear correlation. They could even distinguish demand in one rich country and its impact on the forests of a poorer nation.

“Richer countries are encouraging deforestation through demand for commodities”

“While cocoa consumption in Germany poses the highest risk to the forests in Côte d’Ivoire and Ghana, deforestation in coastal Tanzania is dominated by Japanese consumers for some agricultural commodities, such as cotton and sesame seed,” they write.

“China shares the most significant responsibility for deforestation in Indochina − particularly in northern Laos for timber and rubber.”

Ironically, many of the richer nations have expanded the areas of forest on their own soil. More than 90% of the deforestation caused by five of the G7 nations was beyond their own borders. In effect, the rich were exporting the destruction of the natural world, and the cost to the planet was disproportionate. The loss of three trees in the Amazon might be more damaging than the loss of 14 trees in Norway, the scientists argue.

“Most forests are in poorer countries who are overwhelmed with economic incentives to cut them down. Our findings show that richer countries are encouraging deforestation through demand for commodities,” said Keiichiro Kanemoto of the Research Institute for Humanity and Nature in Kyoto.

“Policies that aim to preserve forests need to also alleviate poverty. With the coronavirus pandemic, unemployment poses more challenges to forest conservation in developing countries. We want our data to assist in the policy making.”

South American losses

And in the journal Science Advances, a team from the University of Maryland reports on a closer look at the impact of demand for pulpwood, sugar cane, beef, corn and other commodities on one continent: South America, home to some of the world’s most important ecosystems.

They found that human impact on the continent’s land surface just between the years 1985 and 2018 had expanded by 60%. In those years the natural tree cover had dwindled by 16%, and the scale of pasture increased by 23%, cropland by 160% and plantation by 288%.

The sum of all the altered land reached 268 million hectares, or 2.68m sq kms. Argentina, which coincidentally covers 2.73m sq kms, saw an increase of only 23% in human conversion of land use. Brazil tipped the scales with an expansion of 65% in those years.

And, say the researchers, of all this altered land cover on the continent, around 55 million hectares had been degraded − that is, it was no longer functioning as an ecosystem − while being employed for no commercial return. This is the equivalent of more than half a million square kilometres: an area slightly bigger than France.

“No region on Earth is likely to have experienced the scale of land conversion for the sake of agricultural commodity production that South America has,” the authors write. − Climate News Network

Drylands hit harder by poverty than richer regions

The arrival of the rains leaves the drylands hit harder than richer areas. Once again, climate change sows injustice.

LONDON, 7 December, 2020 − Not even the climate can be even-handed. When the rains come they leave the world’s drylands hit harder: the wealthier fare better and the poorest get relatively a little poorer. And the evidence is visible literally at the grassroots.

European scientists have been measuring vegetation growth as recorded in fine detail by satellite observation over the last 20 years. And they report that in the developing world, the vegetation that sprouts after rainfall on arid lands is more meagre, while in the better-off nations the same rainfall on the same kind of dryland terrain produces more healthy growth.

The consequence, researchers warn in the journal Nature Sustainability, could result in more food shortages, more disruption, and growing numbers of climate refugees.

“We observe a clear trend of arid areas developing in a negative direction in the most economically challenged countries,” said Rasmus Fensholt, of the University of Copenhagen, one of the authors.

“Here it is apparent that the growth of vegetation has become increasingly decoupled from the water resources available, and that there is simply less vegetation in relation to the amount of rainfall. The opposite is the case in the wealthiest countries.”

“One consequence of declining vegetation in the world’s poorer arid regions may be an increase in climate refugees from various African countries. There is no indication that the problem will diminish”

Roughly 40% of the Earth’s habitable land is arid or semi-arid, and the global drylands are home to almost a third of all humanity, around half of all the planet’s birds and mammals, as well as providing range for livestock and land for crops. Most of the world’s drylands are also home to many of the world’s least developed countries, and many of the poorest citizenry.

And, in a world of climate change driven by ever-rising global temperatures, fuelled in turn by greenhouse gas emissions from increasing fossil fuel use, things don’t look promising.

Research from the last four decades has repeatedly predicted that although global rainfall may be higher in total, those regions already well-watered will tend to become wetter, while those that have adapted to arid climate regimes will get drier. By the end of this century the proportion defined as dryland may have expanded by 23%.

And although higher temperatures, higher levels of atmospheric carbon and changes in rainfall regimes have had the overall effect of “greening” many of the drylands, those already struggling to survive are getting less benefit from any rain that falls.

The scientists, from Denmark, Norway, Sweden and the Netherlands, made a close analysis of satellite imagery from 2000 to 2015 to identify not rainfall changes, but vegetation productivity in relation to rainfall: they found pronounced differences across regions and continents. Drylands in Africa and Asia fared proportionately less well compared to South America and Australia.

Upward trend reversed

What made the difference, they think, is the number and the plight of the people on whom the rain fell. Rapid population growth in Africa meant greater pressure on land less suitable for agriculture, and more intense grazing on already fragile grassland cover.

In the richer nations, conversely, farms had expanded and intensified with help from fertiliser and irrigation.

This is not the first study to find that in a world of climate change, the poorest − among them those who have contributed least to global heating − will be hit hardest. The match of more people with less productive land can only mean more competition for less food at higher prices.

“One consequence of declining vegetation in the world’s poorer arid regions may be an increase in climate refugees from various African countries. According to what we have seen in this study, there is no indication that the problem will diminish in future,” Professor Fensholt said.

“We have been pleased to see that, for a number of years, vegetation has been on an upwards trend in arid regions. But if we dig only a tiny bit deeper and look at how successfully precipitation has translated into vegetation, then climate change seems to be hitting unevenly, which is troubling.” − Climate News Network

The arrival of the rains leaves the drylands hit harder than richer areas. Once again, climate change sows injustice.

LONDON, 7 December, 2020 − Not even the climate can be even-handed. When the rains come they leave the world’s drylands hit harder: the wealthier fare better and the poorest get relatively a little poorer. And the evidence is visible literally at the grassroots.

European scientists have been measuring vegetation growth as recorded in fine detail by satellite observation over the last 20 years. And they report that in the developing world, the vegetation that sprouts after rainfall on arid lands is more meagre, while in the better-off nations the same rainfall on the same kind of dryland terrain produces more healthy growth.

The consequence, researchers warn in the journal Nature Sustainability, could result in more food shortages, more disruption, and growing numbers of climate refugees.

“We observe a clear trend of arid areas developing in a negative direction in the most economically challenged countries,” said Rasmus Fensholt, of the University of Copenhagen, one of the authors.

“Here it is apparent that the growth of vegetation has become increasingly decoupled from the water resources available, and that there is simply less vegetation in relation to the amount of rainfall. The opposite is the case in the wealthiest countries.”

“One consequence of declining vegetation in the world’s poorer arid regions may be an increase in climate refugees from various African countries. There is no indication that the problem will diminish”

Roughly 40% of the Earth’s habitable land is arid or semi-arid, and the global drylands are home to almost a third of all humanity, around half of all the planet’s birds and mammals, as well as providing range for livestock and land for crops. Most of the world’s drylands are also home to many of the world’s least developed countries, and many of the poorest citizenry.

And, in a world of climate change driven by ever-rising global temperatures, fuelled in turn by greenhouse gas emissions from increasing fossil fuel use, things don’t look promising.

Research from the last four decades has repeatedly predicted that although global rainfall may be higher in total, those regions already well-watered will tend to become wetter, while those that have adapted to arid climate regimes will get drier. By the end of this century the proportion defined as dryland may have expanded by 23%.

And although higher temperatures, higher levels of atmospheric carbon and changes in rainfall regimes have had the overall effect of “greening” many of the drylands, those already struggling to survive are getting less benefit from any rain that falls.

The scientists, from Denmark, Norway, Sweden and the Netherlands, made a close analysis of satellite imagery from 2000 to 2015 to identify not rainfall changes, but vegetation productivity in relation to rainfall: they found pronounced differences across regions and continents. Drylands in Africa and Asia fared proportionately less well compared to South America and Australia.

Upward trend reversed

What made the difference, they think, is the number and the plight of the people on whom the rain fell. Rapid population growth in Africa meant greater pressure on land less suitable for agriculture, and more intense grazing on already fragile grassland cover.

In the richer nations, conversely, farms had expanded and intensified with help from fertiliser and irrigation.

This is not the first study to find that in a world of climate change, the poorest − among them those who have contributed least to global heating − will be hit hardest. The match of more people with less productive land can only mean more competition for less food at higher prices.

“One consequence of declining vegetation in the world’s poorer arid regions may be an increase in climate refugees from various African countries. According to what we have seen in this study, there is no indication that the problem will diminish in future,” Professor Fensholt said.

“We have been pleased to see that, for a number of years, vegetation has been on an upwards trend in arid regions. But if we dig only a tiny bit deeper and look at how successfully precipitation has translated into vegetation, then climate change seems to be hitting unevenly, which is troubling.” − Climate News Network