Islands in the sky, global warming, and Pikas
Apr 13, 2015 17:53:16 GMT
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Post by Hill on Apr 13, 2015 17:53:16 GMT
By now almost everyone must be aware of global warming. The vast majority of scientific research and record-keeping indicate that it is due to human activity. I am completely convinced by the evidence. But even if you don't agree that humans are a major cause, the temperature records don't lie; the earth is warming - quickly. And most have heard of the predicament faced by low lying coastal areas and in particular oceanic islands. But there is another "island habitat" of sorts - high mountains whose environment most closely matches habitats hundreds or thousands of miles closer to the poles. These mountains stand like islands and island arcs high above much warmer environments. As global warming progresses, warmth creeps upslope much faster than sea level is rising in the oceans. Species that depend upon not having to endure higher temperatures are rapidly, and literally, losing ground, just like mountain glaciers around the world.
One of these species is the American Pika, the smallest North American member of the rabbit family.
Pika and range map credit: www.washington.edu
The Pika lives in rock talus areas that accumulate beneath mountain cliffs. It collects grasses, dries them into hay on rocks in the summer sun, and stores the hay away for the long cold months of mountain winters. The Pika is disappearing from recorded colonies at low altitudes (particularly from low latitude mountains). The evidence is not absolutely conclusive yet, but the habitat loss is very likely due to global warming. Pikas have dense fur which is not shed in summer and temperatures above 75 degrees F are quickly fatal. As higher temperatures climb the mountain slopes the pikas are being forced higher and higher and within a very short time will be in just as much of a predicament as oceanic island dwellers. Wikipedia Link - American Pika Wikipedia Link - All Pikas
Below are several quotes:
Clambering through a pika-less stretch of "talus" -- fields of rock fragments fallen from the peaks above where pikas hide from predators and the hot midday sun -- Ray told us how these "local extinctions" point to global warming. "They're going extinct from many of the lower elevations," Ray said. "If the current trends continue at the rate they're going right now, it's very likely that pikas will be extinct within the next 100 years."
"There's less snow cover now, due to global warming," biologist Andrew Smith of the University of Arizona told ABC. "A number of the empty colonies we're discovering in spring have hay piles only half-eaten. It's strong evidence they died during the winter, and the winters -- especially at those lower elevation colonies -- are often seeing less snow now because of global warming."
Longtime pika scientist Erik Beever reports that of 25 well-documented sites he has studied in the Great Basin (the area between the Rockies and the California-Oregon ranges) he now finds eight of them empty.
"The pikas are completely gone from a third of their sites, " Beever told us. "It's clearly related to global warming."
"Pikas are poor dispersers -- they can't just race over and recolonize an old site from another mountain," Beever explained.
"It's almost always too hot down in the valleys they'd have to cross," he said. "They'd run into uncrossable highways that weren't there when the last ice age ended. And they'd have to be out in the open, so they'd be in great danger of getting picked off by hawks."
So, with temperatures rising, the only way pikas have to go is up, chased by the steadily climbing warmer air that climate change is bringing -- and will continue to bring -- for at least the next 50 years, scientists say. And when that heat reaches the top of a peak, that mountain's pikas are finished. SOURCE
Global Climate Change Impacts in the United States (Thomas R. Karl, Jerry M. Melillo, and Thomas C. Peterson, (eds.). Cambridge University Press, 2009.) From the lead paragraphs:
Observations show that warming of the climate is unequivocal. The global warming observed over the past 50 years is due primarily to human-induced emissions of heat-trapping gases. These emissions come mainly from the burning of fossil fuels (coal, oil, and gas), with important contributions from the clearing of forests, agricultural practices, and other activities.
Warming over this century is projected to be considerably greater than over the last century. The global average temperature since 1900 has risen by about 1.5ºF. By 2100, it is projected to rise another 2 to 11.5ºF. The U.S. average temperature has risen by a comparable amount and is very likely to rise more than the global average over this century, with some variation from place to place. Several factors will determine future temperature increases. Increases at the lower end of this range are more likely if global heat-trapping gas emissions are cut substantially. If emissions continue to rise at or near current rates, temperature increases are more likely to be near the upper end of the range. Volcanic eruptions or other natural variations could temporarily counteract some of the human-induced warming, slowing the rise in global temperature, but these effects would only last a few years.
Reducing emissions of carbon dioxide would lessen warming over this century and beyond. Sizable early cuts in emissions would significantly reduce the pace and the overall amount of climate change. Earlier cuts in emissions would have a greater effect in reducing climate change than comparable reductions made later. In addition, reducing emissions of some shorter-lived heat-trapping gases, such as methane, and some types of particles, such as soot, would begin to reduce warming within weeks to decades.
Climate-related changes have already been observed globally and in the United States. These include increases in air and water temperatures, reduced frost days, increased frequency and intensity of heavy downpours, a rise in sea level, and reduced snow cover, glaciers, permafrost, and sea ice. A longer ice-free period on lakes and rivers, lengthening of the growing season, and increased water vapor in the atmosphere have also been observed. Over the past 30 years, temperatures have risen faster in winter than in any other season, with average winter temperatures in the Midwest and northern Great Plains increasing more than 7ºF. Some of the changes have been faster than previous assessments had suggested. SOURCE
This post was derived from information in THIS THREAD in the oGEC archives.
One of these species is the American Pika, the smallest North American member of the rabbit family.
Pika and range map credit: www.washington.edu
The Pika lives in rock talus areas that accumulate beneath mountain cliffs. It collects grasses, dries them into hay on rocks in the summer sun, and stores the hay away for the long cold months of mountain winters. The Pika is disappearing from recorded colonies at low altitudes (particularly from low latitude mountains). The evidence is not absolutely conclusive yet, but the habitat loss is very likely due to global warming. Pikas have dense fur which is not shed in summer and temperatures above 75 degrees F are quickly fatal. As higher temperatures climb the mountain slopes the pikas are being forced higher and higher and within a very short time will be in just as much of a predicament as oceanic island dwellers. Wikipedia Link - American Pika Wikipedia Link - All Pikas
Below are several quotes:
Clambering through a pika-less stretch of "talus" -- fields of rock fragments fallen from the peaks above where pikas hide from predators and the hot midday sun -- Ray told us how these "local extinctions" point to global warming. "They're going extinct from many of the lower elevations," Ray said. "If the current trends continue at the rate they're going right now, it's very likely that pikas will be extinct within the next 100 years."
"There's less snow cover now, due to global warming," biologist Andrew Smith of the University of Arizona told ABC. "A number of the empty colonies we're discovering in spring have hay piles only half-eaten. It's strong evidence they died during the winter, and the winters -- especially at those lower elevation colonies -- are often seeing less snow now because of global warming."
Longtime pika scientist Erik Beever reports that of 25 well-documented sites he has studied in the Great Basin (the area between the Rockies and the California-Oregon ranges) he now finds eight of them empty.
"The pikas are completely gone from a third of their sites, " Beever told us. "It's clearly related to global warming."
"Pikas are poor dispersers -- they can't just race over and recolonize an old site from another mountain," Beever explained.
"It's almost always too hot down in the valleys they'd have to cross," he said. "They'd run into uncrossable highways that weren't there when the last ice age ended. And they'd have to be out in the open, so they'd be in great danger of getting picked off by hawks."
So, with temperatures rising, the only way pikas have to go is up, chased by the steadily climbing warmer air that climate change is bringing -- and will continue to bring -- for at least the next 50 years, scientists say. And when that heat reaches the top of a peak, that mountain's pikas are finished. SOURCE
Global Climate Change Impacts in the United States (Thomas R. Karl, Jerry M. Melillo, and Thomas C. Peterson, (eds.). Cambridge University Press, 2009.) From the lead paragraphs:
Observations show that warming of the climate is unequivocal. The global warming observed over the past 50 years is due primarily to human-induced emissions of heat-trapping gases. These emissions come mainly from the burning of fossil fuels (coal, oil, and gas), with important contributions from the clearing of forests, agricultural practices, and other activities.
Warming over this century is projected to be considerably greater than over the last century. The global average temperature since 1900 has risen by about 1.5ºF. By 2100, it is projected to rise another 2 to 11.5ºF. The U.S. average temperature has risen by a comparable amount and is very likely to rise more than the global average over this century, with some variation from place to place. Several factors will determine future temperature increases. Increases at the lower end of this range are more likely if global heat-trapping gas emissions are cut substantially. If emissions continue to rise at or near current rates, temperature increases are more likely to be near the upper end of the range. Volcanic eruptions or other natural variations could temporarily counteract some of the human-induced warming, slowing the rise in global temperature, but these effects would only last a few years.
Reducing emissions of carbon dioxide would lessen warming over this century and beyond. Sizable early cuts in emissions would significantly reduce the pace and the overall amount of climate change. Earlier cuts in emissions would have a greater effect in reducing climate change than comparable reductions made later. In addition, reducing emissions of some shorter-lived heat-trapping gases, such as methane, and some types of particles, such as soot, would begin to reduce warming within weeks to decades.
Climate-related changes have already been observed globally and in the United States. These include increases in air and water temperatures, reduced frost days, increased frequency and intensity of heavy downpours, a rise in sea level, and reduced snow cover, glaciers, permafrost, and sea ice. A longer ice-free period on lakes and rivers, lengthening of the growing season, and increased water vapor in the atmosphere have also been observed. Over the past 30 years, temperatures have risen faster in winter than in any other season, with average winter temperatures in the Midwest and northern Great Plains increasing more than 7ºF. Some of the changes have been faster than previous assessments had suggested. SOURCE
This post was derived from information in THIS THREAD in the oGEC archives.
