Tag Archives: Desertification

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Emissions rate puts billion more at risk

FOR IMMEDIATE RELEASE An extensive new study by climate impact researchers warns that humans will struggle to cope with drastic and rapid changes to the planet unless greenhouse gas emissions rates are cut now London, 8 October − Allowing the Earth’s temperature to rise by more than 2ºC will see dramatic changes in vegetation across the planet and expose a billion more people to severe water scarcity, according to new research. So vast are the potential changes that the scientists from the Potsdam Institute for Climate Impact Research (PIK) in Germany comment that they doubt if humans have the capacity to manage the impacts it will have. A temperature rise of 5ºC would cause all ice-free land on the planet to experience dramatic changes in its eco-systems – for example, tundra turning to forests and African grasslands to deserts. In a paper published today in the international scientific journal Earth System Dynamics, the scientists say they are surprised at how much worse the impacts would become once the 2ºC threshold is passed. At the moment, they say, the failure of politicians to make commitments to cut emissions means that the temperature is set to reach and pass the danger zone of 3.5ºC. While the scientists spell out what will happen to the vegetation and the water availability, they do not venture into predicting what conflict might arise if a billion people or more whose food supply would collapse embarked on mass migration to avoid starvation. The “green” areas of the world most affected are the grasslands of Eastern India, shrub lands of the Tibetan Plateau, the forests of Northern Canada, and the savannas of Ethiopia and Somalia.  The melting permafrost of the Siberian tundra will also be significant, releasing further greenhouse gases. The changes in vegetation are only part of the story. The report also concentrates on the effect of temperature on water shortages for the human population. Even if global warming is limited to 2ºC above pre-industrial levels, another 500 million people could suffer water scarcity, and this will grow substantially as the temperature rises.

Water scarcity

Dr Dieter Gerten, research expert on water scarcity, and lead author of one of the three studies contained in the PIK paper, said mean global warming of 2ºC − the target set by the international community − is projected to expose an additional 8% of humankind to new or increased water scarcity. However, a rise of 3.5 degrees – likely to occur if national emissions reductions remain at currently pledged levels – would affect 11% of the world population, while a rise of 5 degrees could increase this to 13%. “If population growth continues, by the end of our century under a business-as-usual scenario these figures would equate to well over one billion lives touched,” Gerten says. “And this is on top of the more than one billion people already living in water-scarce regions today.” Parts of Asia, North Africa, the Mediterranean and the Middle East are particularly vulnerable to further water scarcity.  The eastern side of the United States and northern Mexico, already short of water, will suffer further stress. Maps published with the paper show the areas most at risk from both water shortages and vegetation changes. One of the worst affected regions is an area that includes Pakistan and the border area of India − which is already suffering from floods, droughts and a subsequent loss of crop production.

Dire consequences

The scientists use their findings to show that the current world leaders have the key to the fate of the planet. If they reduce emissions now, they could prevent the worst of the temperature rises, but if they fail to do so the consequences will be dire. The paper says a warming of 5ºC − likely to happen in the next century if climate change goes on unabated − would put nearly all terrestrial natural ecosystems at risk of severe change. “So despite the uncertainties, the findings clearly demonstrate that there is a large difference in the risk of global ecosystem change under a scenario of no climate change mitigation, compared to one of ambitious mitigation,” says geo-ecologist Sebastian Ostberg, lead author of the third section of the study. While the report does not speculate on the actual effects these changes will have on the ability of the human population to survive, the scientists permit themselves the observation that it is hard to see how humans can adapt to such rapid changes. Much more irrigation would be needed to grow the same amount of food, the scientists suggest, but this would put even more strain on scarce resources. − Climate News Network

FOR IMMEDIATE RELEASE An extensive new study by climate impact researchers warns that humans will struggle to cope with drastic and rapid changes to the planet unless greenhouse gas emissions rates are cut now London, 8 October − Allowing the Earth’s temperature to rise by more than 2ºC will see dramatic changes in vegetation across the planet and expose a billion more people to severe water scarcity, according to new research. So vast are the potential changes that the scientists from the Potsdam Institute for Climate Impact Research (PIK) in Germany comment that they doubt if humans have the capacity to manage the impacts it will have. A temperature rise of 5ºC would cause all ice-free land on the planet to experience dramatic changes in its eco-systems – for example, tundra turning to forests and African grasslands to deserts. In a paper published today in the international scientific journal Earth System Dynamics, the scientists say they are surprised at how much worse the impacts would become once the 2ºC threshold is passed. At the moment, they say, the failure of politicians to make commitments to cut emissions means that the temperature is set to reach and pass the danger zone of 3.5ºC. While the scientists spell out what will happen to the vegetation and the water availability, they do not venture into predicting what conflict might arise if a billion people or more whose food supply would collapse embarked on mass migration to avoid starvation. The “green” areas of the world most affected are the grasslands of Eastern India, shrub lands of the Tibetan Plateau, the forests of Northern Canada, and the savannas of Ethiopia and Somalia.  The melting permafrost of the Siberian tundra will also be significant, releasing further greenhouse gases. The changes in vegetation are only part of the story. The report also concentrates on the effect of temperature on water shortages for the human population. Even if global warming is limited to 2ºC above pre-industrial levels, another 500 million people could suffer water scarcity, and this will grow substantially as the temperature rises.

Water scarcity

Dr Dieter Gerten, research expert on water scarcity, and lead author of one of the three studies contained in the PIK paper, said mean global warming of 2ºC − the target set by the international community − is projected to expose an additional 8% of humankind to new or increased water scarcity. However, a rise of 3.5 degrees – likely to occur if national emissions reductions remain at currently pledged levels – would affect 11% of the world population, while a rise of 5 degrees could increase this to 13%. “If population growth continues, by the end of our century under a business-as-usual scenario these figures would equate to well over one billion lives touched,” Gerten says. “And this is on top of the more than one billion people already living in water-scarce regions today.” Parts of Asia, North Africa, the Mediterranean and the Middle East are particularly vulnerable to further water scarcity.  The eastern side of the United States and northern Mexico, already short of water, will suffer further stress. Maps published with the paper show the areas most at risk from both water shortages and vegetation changes. One of the worst affected regions is an area that includes Pakistan and the border area of India − which is already suffering from floods, droughts and a subsequent loss of crop production.

Dire consequences

The scientists use their findings to show that the current world leaders have the key to the fate of the planet. If they reduce emissions now, they could prevent the worst of the temperature rises, but if they fail to do so the consequences will be dire. The paper says a warming of 5ºC − likely to happen in the next century if climate change goes on unabated − would put nearly all terrestrial natural ecosystems at risk of severe change. “So despite the uncertainties, the findings clearly demonstrate that there is a large difference in the risk of global ecosystem change under a scenario of no climate change mitigation, compared to one of ambitious mitigation,” says geo-ecologist Sebastian Ostberg, lead author of the third section of the study. While the report does not speculate on the actual effects these changes will have on the ability of the human population to survive, the scientists permit themselves the observation that it is hard to see how humans can adapt to such rapid changes. Much more irrigation would be needed to grow the same amount of food, the scientists suggest, but this would put even more strain on scarce resources. − Climate News Network

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Desert yields clues to species’ survival

FOR IMMEDIATE RELEASE Research into one of the world’s oldest and driest deserts has unearthed evidence of the evolutionary timeline for species that have avoided extinction by adapting to dramatic climate change LONDON, June 26 − Biodiversity’s response to global warming is difficult to predict, but new research shows that species in the distant past have adapted to, and colonised, new and increasingly arid desert zones during a period of dramatic change. The less encouraging finding from the University of Chile scientists who have studied geological evidence from the Atacama-Sechura desert region − one of the Earth’s oldest and driest deserts − is that this adaptation takes about six million years. Any wildlife response to dramatic climate change – and the kind predicted in the worst case scenario for the 21st century is certainly in the dramatic category − depends on a very large number of factors.

Barriers to movement

These include how fast plants or small animals can move to cooler zones south or north; what barriers – such as mountain ranges, lakes, cities, motorways or farms − there might be to movement; and, of course, whether the ecosystem that supports any particular species can move at the same rate. Researchers have repeatedly warned of mass extinction under conditions of climate change, but it has been much harder to calculate the rates at which species might adapt or evolve, and populations recover, in new habitats. However, there are lessons to be learned from the recent geological past − long before Homo sapiens began to create extra difficulties for the rest of creation. Climate scientists can date changes in global temperatures with reasonable accuracy, palaeontologists can identify and date fossils of characteristic climate zone species with some precision, and geneticists can measure the rate at which DNA has evolved to adapt to new environments. This last technique now delivers a good measure of evolutionary timelines. Pablo Guerrero and fellow researchers at the University of Chile’s Department of Ecological Sciences report in the Proceedings of the National Academy of Sciences that they used geological evidence to put dates to the rainfall history of the ancient Atacama-Sechura desert region of Chile and Peru and the DNA readings to measure the rates at which three different kinds of plant and one genus of lizard evolved to colonise the new habitat.

Huge time lags

They found that these groups of plants and animals made their homes in the desert only in the last 10 million years – a good 20 million years after the onset of aridity in the region. There were also huge lags – from 4 million to 14 million years − between the time these creatures moved into the desert region and when they colonised the hyper-arid places. These ultra-dry parts of the region developed about 8 million years ago, but the most diverse of the plant group moved in only two million years ago. “Similar evolutionary lag times may occur in other organisms and habitats, but these results are important in suggesting that many lineages may require very long time scales to adapt to modern desertification and climate change,” the scientists in Chile report. − Climate News Network        

FOR IMMEDIATE RELEASE Research into one of the world’s oldest and driest deserts has unearthed evidence of the evolutionary timeline for species that have avoided extinction by adapting to dramatic climate change LONDON, June 26 − Biodiversity’s response to global warming is difficult to predict, but new research shows that species in the distant past have adapted to, and colonised, new and increasingly arid desert zones during a period of dramatic change. The less encouraging finding from the University of Chile scientists who have studied geological evidence from the Atacama-Sechura desert region − one of the Earth’s oldest and driest deserts − is that this adaptation takes about six million years. Any wildlife response to dramatic climate change – and the kind predicted in the worst case scenario for the 21st century is certainly in the dramatic category − depends on a very large number of factors.

Barriers to movement

These include how fast plants or small animals can move to cooler zones south or north; what barriers – such as mountain ranges, lakes, cities, motorways or farms − there might be to movement; and, of course, whether the ecosystem that supports any particular species can move at the same rate. Researchers have repeatedly warned of mass extinction under conditions of climate change, but it has been much harder to calculate the rates at which species might adapt or evolve, and populations recover, in new habitats. However, there are lessons to be learned from the recent geological past − long before Homo sapiens began to create extra difficulties for the rest of creation. Climate scientists can date changes in global temperatures with reasonable accuracy, palaeontologists can identify and date fossils of characteristic climate zone species with some precision, and geneticists can measure the rate at which DNA has evolved to adapt to new environments. This last technique now delivers a good measure of evolutionary timelines. Pablo Guerrero and fellow researchers at the University of Chile’s Department of Ecological Sciences report in the Proceedings of the National Academy of Sciences that they used geological evidence to put dates to the rainfall history of the ancient Atacama-Sechura desert region of Chile and Peru and the DNA readings to measure the rates at which three different kinds of plant and one genus of lizard evolved to colonise the new habitat.

Huge time lags

They found that these groups of plants and animals made their homes in the desert only in the last 10 million years – a good 20 million years after the onset of aridity in the region. There were also huge lags – from 4 million to 14 million years − between the time these creatures moved into the desert region and when they colonised the hyper-arid places. These ultra-dry parts of the region developed about 8 million years ago, but the most diverse of the plant group moved in only two million years ago. “Similar evolutionary lag times may occur in other organisms and habitats, but these results are important in suggesting that many lineages may require very long time scales to adapt to modern desertification and climate change,” the scientists in Chile report. − Climate News Network        

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More sunshine in Spain not always good news

For immediate release Over 40 years cloud cover has been steadily falling in Spain providing more sunshine but that is a threat as well as a bonus. London, 9 June  – The sun is getting more powerful in Spain increasing the threat of desertification but providing more energy for the country’s growing solar industry – the largest in Europe. According to a study the University of Girona and the Federal Institute of Technology (ETH) in Zurich solar radiation in Spain has increased by 2.3% every decade since the 1980s. This is mainly due to the decrease in clouds, which has increased the direct sunlight. The largest increase was in the summer and autumn, but the sun shone more in the winter and spring as well. Solar radiation is measured both as direct sunlight and diffuse light via clouds, atmospheric gases and aerosols. What was striking was the decrease in the diffuse component of sunlight according to the research published in the magazine ‘Global and Planetary Change’. Clouds decrease One of the authors, Arturo Sánchez-Lorenzo, currently a postdoctoral researcher at the University of Girona, said the amount of sunlight reaching the Spanish land surface had increased in every decade since 1980. “Only in 1991 and 1992 did diffuse radiation rise, and this was due to the ashes from Mount Pinatubo (volcanic eruption in the Philippines). “The explanation (of the increase) lies in the fact that in Spain the amount of cloud has decreased markedly since the 1980s – as we have ascertained through other studies – and the tropospheric aerosol load may also have decreased,” said Sánchez Lorenzo. “It seems to be very simple: fewer clouds result in higher solar radiation on the surface.” Skin cancer According to the scientists, this increase may also go hand in hand with more ultraviolet rays, an excess of which presents a health risk, potentially leading to skin cancer. The increase in global solar radiation is a phenomenon that has been observed in other parts of the world for almost 30 years, especially in developed countries, and it has been named “global brightening”. The fall in the diffuse component has also been observed in Central European and Eastern countries. The team behind the study has not yet analysed the solar radiation data for 2011-2013 provided by the Spanish State Meteorological Agency, but the data from other European weather stations suggests that this brightening is still on the rise. “Studies such as these may be of interest to the solar energy industry, especially in countries like Spain, where not only do we already have a lot of direct solar radiation but now we are getting even more,” said another of the authors, Josep Calbó, who is a professor at the University of Girona. Deserts Until the recent recession began to bite Spain was in the middle of a building boom for all types of solar energy capture. Since 2010 Spain has been the world leader in concentrated solar power, a method of directing the sun’s rays with mirrors to boil water or oil to drive turbines and generate electricity. By the end of 2012 more than 2,000 megawatts of concentrated solar power had been installed, the equivalent of two large conventional power stations. Although the rate of increase has slowed solar power is expected to contribute an increasingly large share of the country’s electricity needs over coming decades as large areas are now too dry for agriculture. On the downside there is serious concern about the lack of rainfall and the increasing risk of desertification in the south of the country. The increase in sunshine is in line with scientific predictions for the northern Mediterranean coast and Italy, France and Greece are all threatened with desert conditions if the trend continues. All four countries are members of the United Nations Convention to Combat Desertification and are taking measures like planting forests to try and prevent the Sahara Desert crossing the Mediterranean to Europe as is predicted by long term climate models. – Climate News Network

For immediate release Over 40 years cloud cover has been steadily falling in Spain providing more sunshine but that is a threat as well as a bonus. London, 9 June  – The sun is getting more powerful in Spain increasing the threat of desertification but providing more energy for the country’s growing solar industry – the largest in Europe. According to a study the University of Girona and the Federal Institute of Technology (ETH) in Zurich solar radiation in Spain has increased by 2.3% every decade since the 1980s. This is mainly due to the decrease in clouds, which has increased the direct sunlight. The largest increase was in the summer and autumn, but the sun shone more in the winter and spring as well. Solar radiation is measured both as direct sunlight and diffuse light via clouds, atmospheric gases and aerosols. What was striking was the decrease in the diffuse component of sunlight according to the research published in the magazine ‘Global and Planetary Change’. Clouds decrease One of the authors, Arturo Sánchez-Lorenzo, currently a postdoctoral researcher at the University of Girona, said the amount of sunlight reaching the Spanish land surface had increased in every decade since 1980. “Only in 1991 and 1992 did diffuse radiation rise, and this was due to the ashes from Mount Pinatubo (volcanic eruption in the Philippines). “The explanation (of the increase) lies in the fact that in Spain the amount of cloud has decreased markedly since the 1980s – as we have ascertained through other studies – and the tropospheric aerosol load may also have decreased,” said Sánchez Lorenzo. “It seems to be very simple: fewer clouds result in higher solar radiation on the surface.” Skin cancer According to the scientists, this increase may also go hand in hand with more ultraviolet rays, an excess of which presents a health risk, potentially leading to skin cancer. The increase in global solar radiation is a phenomenon that has been observed in other parts of the world for almost 30 years, especially in developed countries, and it has been named “global brightening”. The fall in the diffuse component has also been observed in Central European and Eastern countries. The team behind the study has not yet analysed the solar radiation data for 2011-2013 provided by the Spanish State Meteorological Agency, but the data from other European weather stations suggests that this brightening is still on the rise. “Studies such as these may be of interest to the solar energy industry, especially in countries like Spain, where not only do we already have a lot of direct solar radiation but now we are getting even more,” said another of the authors, Josep Calbó, who is a professor at the University of Girona. Deserts Until the recent recession began to bite Spain was in the middle of a building boom for all types of solar energy capture. Since 2010 Spain has been the world leader in concentrated solar power, a method of directing the sun’s rays with mirrors to boil water or oil to drive turbines and generate electricity. By the end of 2012 more than 2,000 megawatts of concentrated solar power had been installed, the equivalent of two large conventional power stations. Although the rate of increase has slowed solar power is expected to contribute an increasingly large share of the country’s electricity needs over coming decades as large areas are now too dry for agriculture. On the downside there is serious concern about the lack of rainfall and the increasing risk of desertification in the south of the country. The increase in sunshine is in line with scientific predictions for the northern Mediterranean coast and Italy, France and Greece are all threatened with desert conditions if the trend continues. All four countries are members of the United Nations Convention to Combat Desertification and are taking measures like planting forests to try and prevent the Sahara Desert crossing the Mediterranean to Europe as is predicted by long term climate models. – Climate News Network