Tag Archives: Snow cover

Loss of snow in California to hit winter sports and water supply

FOR IMMEDIATE RELEASE “Clear and compelling evidence” shows that winter snows vital for tourism and agriculture are in rapid decline in Southern California. LONDON, 21 June – By mid century, the snow-capped mountains of Southern California will be a lot less snowy, according to a new study from the University of California Los Angeles. The mountains beyond Pasadena, Hollywood, Beverly Hills, Venice Beach and other iconic addresses will have 30 to 40 per cent less snow on top and none at all at lower elevations. And by 2100, snowfall could be reduced to about a third of its level in 2000. Alex Hall, of UCLA’s department of atmospheric and oceanic sciences, warned “Climate change has become inevitable, and we’re going to lose a substantial amount of snow by mid-century. But our choices matter. By the end of the century there will be stark differences in how much snowfall remains, depending on whether we begin to mitigate greenhouse gas emissions.” The study was produced with funding from the City of Los Angeles – the city’s mayor Antonio Villaraigosa called it “clear and compelling” – and it examined snowfall in the San Gabriel and San Bernadino mountains and other ranges. The consequences for tourist and leisure industries could be considerable: local enthusiasts use the slopes for skiing and snowboarding; lower snowfalls could have implications for water supplies, agriculture and increased flooding from more frequent rains. More flooding The scientists used climate models and real data from local townships to quantify future snow forecasts, but did not measure snow melt. Earlier research had established that the city and its environs could expect to experience a warming of 4° to 5°F (around 2.5°C) by mid century. By then, the snowpack would be melting 16 days earlier than it did at the beginning of the century. Temperatures would fall to freezing later, and less often, so what fell would be rain, with quicker runoff and more flooding as a consequence. The researcher considered two scenarios – one the notorious “business as usual” prospect, in which greenhouse gas emissions continued to rise without restraint, and the other a world in which governments and society tried to significantly reduce emissions. By 2050, under the mitigation scenario, snowfall would be reduced 31% by 2050, but would stay relatively stable and only be at 33% below baseline by 2100. If the world fails to take action to mitigate climate change, by 2100 however, loss of snow is expected to reach 67% by the end of the century. “Los Angeles must begin today to prepare for climate change,” said Mayor Villaraigosa. “We invested in this study and created the AdaptLA framework to craft innovative solutions and preserve our quality of life for the next generation of Angelenos.” – Climate News Network

FOR IMMEDIATE RELEASE “Clear and compelling evidence” shows that winter snows vital for tourism and agriculture are in rapid decline in Southern California. LONDON, 21 June – By mid century, the snow-capped mountains of Southern California will be a lot less snowy, according to a new study from the University of California Los Angeles. The mountains beyond Pasadena, Hollywood, Beverly Hills, Venice Beach and other iconic addresses will have 30 to 40 per cent less snow on top and none at all at lower elevations. And by 2100, snowfall could be reduced to about a third of its level in 2000. Alex Hall, of UCLA’s department of atmospheric and oceanic sciences, warned “Climate change has become inevitable, and we’re going to lose a substantial amount of snow by mid-century. But our choices matter. By the end of the century there will be stark differences in how much snowfall remains, depending on whether we begin to mitigate greenhouse gas emissions.” The study was produced with funding from the City of Los Angeles – the city’s mayor Antonio Villaraigosa called it “clear and compelling” – and it examined snowfall in the San Gabriel and San Bernadino mountains and other ranges. The consequences for tourist and leisure industries could be considerable: local enthusiasts use the slopes for skiing and snowboarding; lower snowfalls could have implications for water supplies, agriculture and increased flooding from more frequent rains. More flooding The scientists used climate models and real data from local townships to quantify future snow forecasts, but did not measure snow melt. Earlier research had established that the city and its environs could expect to experience a warming of 4° to 5°F (around 2.5°C) by mid century. By then, the snowpack would be melting 16 days earlier than it did at the beginning of the century. Temperatures would fall to freezing later, and less often, so what fell would be rain, with quicker runoff and more flooding as a consequence. The researcher considered two scenarios – one the notorious “business as usual” prospect, in which greenhouse gas emissions continued to rise without restraint, and the other a world in which governments and society tried to significantly reduce emissions. By 2050, under the mitigation scenario, snowfall would be reduced 31% by 2050, but would stay relatively stable and only be at 33% below baseline by 2100. If the world fails to take action to mitigate climate change, by 2100 however, loss of snow is expected to reach 67% by the end of the century. “Los Angeles must begin today to prepare for climate change,” said Mayor Villaraigosa. “We invested in this study and created the AdaptLA framework to craft innovative solutions and preserve our quality of life for the next generation of Angelenos.” – Climate News Network

Fast emissions cuts could save species

EMBARGOED until 1700 GMT on Sunday 12 May Acting quickly to reduce greenhouse gas emissions could provide more time for many species to adapt to the different conditions which climate change will bring to the zones where they can survive. LONDON, 12 May – Without serious action to limit global warming, more than half of all land plants and a third of all animals could find their living space dramatically reduced later this century. That is, if global average temperatures rise by 4°C the climatic regions in which these creatures thrive will shift towards the poles, habitats will dwindle, ecosystems will alter, and ever greater numbers of species will struggle to survive in ever more constrained conditions. That’s the bad news. The somewhat less bad news is that stringent and dramatic reductions in greenhouse gas emissions could buy time: about another four decades in which humanity’s fellow species could adapt to new circumstances. Rachel Warren of the University of East Anglia and colleagues in the UK, Australia and Colombia report in Nature Climate Change that they used a 21st century creation, the Global Biodiversity Information Facility (GBIF), based in Copenhagen, Denmark, to examine the known ranges and habitats of more than 48,000 species of plant and animal and tried to calculate how these would be affected by “business as usual” scenarios for greenhouse gas emissions. The GBIF provides access to 400 million biodiversity records from 10,000 datasets of common plants, mammals, birds, reptiles and amphibians provided by 460 research institutions around the world: the researchers sampled less than half of these. They concluded that 55% of plants and 35% of animals could have their climatically suitable range at least halved by the 2080s. Unrestricted growth in carbon emissions could be expected to result in large contractions of range, even amongst common and widespread species. However, losses could be reduced by 60% if, through mitigation policies, the growth in emissions is halted in 2016 or by 40% if halted in 2030.

Sheltering snow

  The proposition that global warming provides a threat to other species of creature is not new, and should not be surprising. In April researchers warned that climatic zones would shift rapidly as temperatures soar. Rare plant species in high mountain regions at the limit of their temperature range can hardly migrate downhill when conditions become uncomfortably warm. Coral reefs in the tropics provide shelter and habitat for a huge range of species, but if the corals bleach as the seas warm, then rarer species could vanish altogether. The loss of Arctic sea ice, notoriously, puts large terrestrial predators such as the polar bear at a disadvantage. If rainforests begin to parch, then the rare species that make their homes there will become even rarer. In January 2004, Chris Thomas of the University of Leeds and colleagues reported in Nature that climate change could provide stresses that could put at risk the survival of up to a million species: a quarter of all land plants and animals could face oblivion by 2050. A new report, just published in Frontiers in Ecology and the Environment, looks at the effect of climate change on what the authors call “the subnivium”: that ecosystem composed of plants and animals that sit out the worst of winter under a sheltering blanket of snow. The spring melt now occurs on average two weeks earlier, and northern hemisphere snow cover in March and April has diminished on average by more than three million square kilometres, according to a team from the University of Wisconsin-Madison. This apparent mellowing of conditions is in fact bad news for reptiles than can survive buried in the snow, but not, for instance, exposed to biting winds, sudden late frosts and blizzards; plants too that begin to grow too early can be killed off or diminished by the return of harsh conditions. Snow offers a stable micro-environment in which insects, reptiles, mammals and plants are at least safe from sudden change. If the snow retreats too soon, then plants and animals perish, and migrating bird species that depend on a diet of spring insects are also at risk.

Buying time

  “There are thresholds beyond which some organisms just won’t be able to make a living”, says the lead author, Jonathan Paul, a forest ecologist. “The subnivium provides a stable environment, but it is also extremely delicate. Once that snow melts, things can change radically.” But this, once again, is research about the impact of global warming on creatures that already survive under precarious conditions. Many creatures are at risk of extinction simply because of loss of habitat, pollution, hunting, overfishing and the conversion of wilderness to agricultural lands, and all the other consequences of rapid human population growth:  global warming is just another potential stress for an already endangered animal or plant. Rachel Warren’s study in Nature Climate Change makes no predictions about extinction: it simply looks at what warming could do to climatic habitats. Her argument is simply that by cutting emissions immediately and slowing warming during this century to 2°C, these losses could be reduced, and could buy another four decades for species to adapt to the next 2°C rise. “While there has been much research on the effect of climate change on rare and endangered species, little has been known about how an increase in global temperature will affect more common species”, she says. “Our research predicts that climate change will greatly reduce the diversity of even very common species found in most parts of the world. This loss of global-scale diversity would significantly impoverish the biosphere and the ecosystem services it provides.” – Climate News Network

EMBARGOED until 1700 GMT on Sunday 12 May Acting quickly to reduce greenhouse gas emissions could provide more time for many species to adapt to the different conditions which climate change will bring to the zones where they can survive. LONDON, 12 May – Without serious action to limit global warming, more than half of all land plants and a third of all animals could find their living space dramatically reduced later this century. That is, if global average temperatures rise by 4°C the climatic regions in which these creatures thrive will shift towards the poles, habitats will dwindle, ecosystems will alter, and ever greater numbers of species will struggle to survive in ever more constrained conditions. That’s the bad news. The somewhat less bad news is that stringent and dramatic reductions in greenhouse gas emissions could buy time: about another four decades in which humanity’s fellow species could adapt to new circumstances. Rachel Warren of the University of East Anglia and colleagues in the UK, Australia and Colombia report in Nature Climate Change that they used a 21st century creation, the Global Biodiversity Information Facility (GBIF), based in Copenhagen, Denmark, to examine the known ranges and habitats of more than 48,000 species of plant and animal and tried to calculate how these would be affected by “business as usual” scenarios for greenhouse gas emissions. The GBIF provides access to 400 million biodiversity records from 10,000 datasets of common plants, mammals, birds, reptiles and amphibians provided by 460 research institutions around the world: the researchers sampled less than half of these. They concluded that 55% of plants and 35% of animals could have their climatically suitable range at least halved by the 2080s. Unrestricted growth in carbon emissions could be expected to result in large contractions of range, even amongst common and widespread species. However, losses could be reduced by 60% if, through mitigation policies, the growth in emissions is halted in 2016 or by 40% if halted in 2030.

Sheltering snow

  The proposition that global warming provides a threat to other species of creature is not new, and should not be surprising. In April researchers warned that climatic zones would shift rapidly as temperatures soar. Rare plant species in high mountain regions at the limit of their temperature range can hardly migrate downhill when conditions become uncomfortably warm. Coral reefs in the tropics provide shelter and habitat for a huge range of species, but if the corals bleach as the seas warm, then rarer species could vanish altogether. The loss of Arctic sea ice, notoriously, puts large terrestrial predators such as the polar bear at a disadvantage. If rainforests begin to parch, then the rare species that make their homes there will become even rarer. In January 2004, Chris Thomas of the University of Leeds and colleagues reported in Nature that climate change could provide stresses that could put at risk the survival of up to a million species: a quarter of all land plants and animals could face oblivion by 2050. A new report, just published in Frontiers in Ecology and the Environment, looks at the effect of climate change on what the authors call “the subnivium”: that ecosystem composed of plants and animals that sit out the worst of winter under a sheltering blanket of snow. The spring melt now occurs on average two weeks earlier, and northern hemisphere snow cover in March and April has diminished on average by more than three million square kilometres, according to a team from the University of Wisconsin-Madison. This apparent mellowing of conditions is in fact bad news for reptiles than can survive buried in the snow, but not, for instance, exposed to biting winds, sudden late frosts and blizzards; plants too that begin to grow too early can be killed off or diminished by the return of harsh conditions. Snow offers a stable micro-environment in which insects, reptiles, mammals and plants are at least safe from sudden change. If the snow retreats too soon, then plants and animals perish, and migrating bird species that depend on a diet of spring insects are also at risk.

Buying time

  “There are thresholds beyond which some organisms just won’t be able to make a living”, says the lead author, Jonathan Paul, a forest ecologist. “The subnivium provides a stable environment, but it is also extremely delicate. Once that snow melts, things can change radically.” But this, once again, is research about the impact of global warming on creatures that already survive under precarious conditions. Many creatures are at risk of extinction simply because of loss of habitat, pollution, hunting, overfishing and the conversion of wilderness to agricultural lands, and all the other consequences of rapid human population growth:  global warming is just another potential stress for an already endangered animal or plant. Rachel Warren’s study in Nature Climate Change makes no predictions about extinction: it simply looks at what warming could do to climatic habitats. Her argument is simply that by cutting emissions immediately and slowing warming during this century to 2°C, these losses could be reduced, and could buy another four decades for species to adapt to the next 2°C rise. “While there has been much research on the effect of climate change on rare and endangered species, little has been known about how an increase in global temperature will affect more common species”, she says. “Our research predicts that climate change will greatly reduce the diversity of even very common species found in most parts of the world. This loss of global-scale diversity would significantly impoverish the biosphere and the ecosystem services it provides.” – Climate News Network

Hare undone by unshed summer coat

FOR IMMEDIATE RELEASE Species which protect themselves by turning white to match the snow of the long northern winters may be caught out as a warming climate reduces the numbers of days of snow cover. LONDON, 4 May – Milder winters mean bad news for the snowshoe hare of western North America. Lepus americanus is famous for two things: an evolutionary camouflage adaptation that keeps it white in the winter snow and turns it a reddish brown in spring and summer; and its intimate population polka with one of the continent’s most glamorous predators, the Canada lynx. When hares are numerous, the lynx population increases. As the numbers of hares diminish, so its predators go hungry and the lynx population starts to drop, giving the snowshoe hares another chance. But the hare may be losing the battle, thanks to climate change. Biologists report in the Proceedings of the National Academy of Sciences that they monitored 148 wild hares in western Montana and observed that the adaptation that gave the hares an advantage in stable climates is likely to work to their disadvantage as temperatures rise, snow cover shrinks and the winters get shorter. The three years of their study included both the shortest and the longest snow seasons since 1970. The researchers found that the spring and autumn moults seemed to occur independently of the arrival of the snows: they conjecture that they may be triggered by changes in daylight length. Since hares don’t get much chance to die of old age – predation comprises 85 to 100% of mortality in different regions and different years – camouflage would play an important role in keeping hares alive long enough to breed and rear their young.

Poster child

  A white hare on brown soil or a brown hare in the snow would both be at a serious disadvantage. Over the three-year period, the researchers had plenty of chances to observe both. They expect “increased coat colour mismatch as snow seasons shorten under future climate change” and without rapid adaptation, this mismatch will increase as much as fourfold by mid-century and eightfold by the late century if humans go on pumping greenhouse gases into the atmosphere at an increasing rate. The average annual duration of snow cover is forecast to fall by 29 to 35 days by mid-century and by 40 to 69 days by the end of the century. Hares, the researchers warn, won’t be the only coat-changing mammals left exposed by ever-shorter winters. They conclude that there is a lot to learn from the plight of the hare (and see our story of 18 January).. “The compelling image of a white animal on a brown snowless background can be a poster child for both educational outreach and for profound scientific inquiry into fitness consequences, mechanisms of seasonal coat colour change, and the potential for rapid local adaptation”, they say. – Climate News Network

FOR IMMEDIATE RELEASE Species which protect themselves by turning white to match the snow of the long northern winters may be caught out as a warming climate reduces the numbers of days of snow cover. LONDON, 4 May – Milder winters mean bad news for the snowshoe hare of western North America. Lepus americanus is famous for two things: an evolutionary camouflage adaptation that keeps it white in the winter snow and turns it a reddish brown in spring and summer; and its intimate population polka with one of the continent’s most glamorous predators, the Canada lynx. When hares are numerous, the lynx population increases. As the numbers of hares diminish, so its predators go hungry and the lynx population starts to drop, giving the snowshoe hares another chance. But the hare may be losing the battle, thanks to climate change. Biologists report in the Proceedings of the National Academy of Sciences that they monitored 148 wild hares in western Montana and observed that the adaptation that gave the hares an advantage in stable climates is likely to work to their disadvantage as temperatures rise, snow cover shrinks and the winters get shorter. The three years of their study included both the shortest and the longest snow seasons since 1970. The researchers found that the spring and autumn moults seemed to occur independently of the arrival of the snows: they conjecture that they may be triggered by changes in daylight length. Since hares don’t get much chance to die of old age – predation comprises 85 to 100% of mortality in different regions and different years – camouflage would play an important role in keeping hares alive long enough to breed and rear their young.

Poster child

  A white hare on brown soil or a brown hare in the snow would both be at a serious disadvantage. Over the three-year period, the researchers had plenty of chances to observe both. They expect “increased coat colour mismatch as snow seasons shorten under future climate change” and without rapid adaptation, this mismatch will increase as much as fourfold by mid-century and eightfold by the late century if humans go on pumping greenhouse gases into the atmosphere at an increasing rate. The average annual duration of snow cover is forecast to fall by 29 to 35 days by mid-century and by 40 to 69 days by the end of the century. Hares, the researchers warn, won’t be the only coat-changing mammals left exposed by ever-shorter winters. They conclude that there is a lot to learn from the plight of the hare (and see our story of 18 January).. “The compelling image of a white animal on a brown snowless background can be a poster child for both educational outreach and for profound scientific inquiry into fitness consequences, mechanisms of seasonal coat colour change, and the potential for rapid local adaptation”, they say. – Climate News Network