CARIBOU CRISIS: Thanks to shifting seasons as a result of climate change, fewer caribou calves are surviving.
Image: Courtesy of Eric Post
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When the summer sea ice goes, the Arctic will lose the ivory gull, Pacific walrus, ringed seal, hooded seal, narwhal and polar bear—all animals that rely on the ice for foraging, reproduction or as refuge from predators. And the sea ice is going, faster and faster: In the past 30 years, minimum sea ice cover in the Arctic Ocean has declined by 45,000 square kilometers annually*—an area twice the size of New Jersey is lost each year.
"Sea ice is like rainforest in the tropics. There are species that can't live without it," says ecologist Eric Post of The Pennsylvania State University, lead author of a paper in the September 11 Science that lays out a broad review of climate change's impact on the Arctic. "It's melting earlier, freezing up later, the contiguous extent is diminishing, and it's happening faster than anyone expected it to happen 10 years ago."
As a wrap-up of ecological studies conducted during the Fourth International Polar Year, Post and a slew of colleagues surveyed the state of the Arctic and found it to be not good, thanks to climate change. "We looked at plants and animals: vascular and nonvascular plants, migratory and nonmigratory animals, vertebrates and invertebrates, saltwater and freshwater, on the land or in the air—everything is changing," Post says. "It doesn't really matter where you look in the Arctic. Things are changing fast."
Rapid change is coming even for animals once thought to be relatively immune, such as caribou. Whereas the nonmigratory population of the animals on the Norwegian Svalbard Islands is burgeoning thanks to more winter snowmelt exposing a greater abundance of plant life for foraging, caribou in other parts of the Arctic are suffering. In spring, plants are blooming earlier in the year thanks to warmer early spring temperatures, but caribou are still calving at the same time, meaning calves are born after most of the food is available, and therefore fewer of them survive.
"I had no idea caribou could be on the brink of collapse. They seemed to have all the right traits to adapt," Post says. "Now they're of critical concern."
Particularly to the peoples of the Arctic who, in many cases, rely on hunting caribou or other animals to survive. "If you talk to the Inuit people in Greenland, they are suffering consequences for something they haven't contributed to themselves," Post notes. "We're taking away elements of a lifestyle that has worked for them for thousands of years. If somebody was doing that to us, don't you think we'd be upset?"
But the list of effects do not stop with the loss of a way of life and sea ice or the mismatch between spring blooms and caribou birthing: red foxes are replacing Arctic foxes farther and farther north; snow cover is diminishing; early spring rains now wash away seal dens, exposing pups; unusually warm periods in winter kill off Arctic plants and they do not rebound the following summer; and lemming and vole populations have crashed and remained at low levels for nearly a decade without recovering, among others. "There's been such a decline in snow cover that it affects [rodent] survival," Post says. "It means that species like snowy owls and Arctic foxes that are dependent on finding rodents will also suffer."
This is all happening with an increasing temperature of just one degree Celsius over the past century. In the next 100 years, the Arctic might warm as much as 6 degrees Celsius according to the United Nations Intergovernmental Panel on Climate Change. "If it were to get to three degrees [Celsius] warmer on average, the Arctic would be a thing of the past," Post says. "Polar bears, long winters of snow, sea ice cover—it wouldn't be the case anymore."
Instead the Arctic might become more like the boreal forests of Alaska, Canada, Scandinavia and Siberia—vast stands of spruce trees that do not support the unique Arctic flora and fauna.
The problem confronting Arctic species is not the warming itself, of course; there have been similar episodes in Earth's history, such as the warming during the transition from the Pleistocene to the Holocene epochs. It is the speed with which the greenhouse gases from fossil fuel burning are warming the globe. "The rate of change is so fast now," Post says. "It's about whether it's getting warmer over several decades or one decade. For a long-lived species there's no chance to keep up, no chance for evolution to keep up."
For his part, Post is hoping that the world will begin to treat Arctic biodiversity as worthy of conservation, more like tropical biodiversity, for example. After all, the Arctic is actually abundant with unique species and ecosystems, not a lifeless, white wasteland.
Post's report is not all bad news: Arctic warming has begun to promote the spread of trees and shrubs farther north, and the growth of these plants can lock up more carbon dioxide as they flourish.
Unfortunately, the warmth is also permitting the northward march of insect pests like the winter moth, which defoliates trees and shrubs and reduces the overall carbon sequestration. Plus, the advance of shrubs is affecting ecosystems, promoting more microbial activity in the soil and, ultimately, the release of methane—another greenhouse gas that traps 25 times as much heat as carbon dioxide over 100 years in the atmosphere.
In other words, warmth—and big changes for the Arctic—will keep coming. "Even if we restrict carbon emissions, it will get warmer," Post says, thanks to the greenhouse gases already in the atmosphere and feedback effects like the loss of sunlight-reflecting sea ice and snow cover. "That doesn't mean we shouldn't curb emissions. It's a matter of damage control.... We might be losing the Arctic as we know it but we need to do everything we can to make sure the problem doesn't spread."
* (9/10/09): This sentence has been changed to clarify that the sea ice loss figure is an annual number.
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19 Comments
Add CommentI think we should view change not with fear but with the attitude of what can we do to make the change less distructive. We can plant grains for the cariboo to eat when their calves are born. Grain that will replant itself. I think we should stop the boo hooing and enjoy the problems to be solved since that is what we do best. solve problems.
Reply | Report Abuse | Link to this"In the past 30 years, minimum sea ice cover in the Arctic Ocean has declined by 45,000 square kilometers—an area twice the size of New Jersey is lost each year."
Reply | Report Abuse | Link to thisHas been lost in the past 30 years, you mean? New Jersey is 22,608 sq km.
Nope. That's an annual figure, but I've amended the sentence to try to make that clear. Thanks Gillen.
Reply | Report Abuse | Link to thisI was just wondering...the amount of green house gas in the atmosphere is attributed to the burning of fossil fuels. Do the vast amount of humans - more every day that has ever been here before, exhaling carbon dioxide, along with all our live stock and pets - contribute in a large scale to the warming effect? There's no doubt that our machines are the biggest contributor, but we all breathe - every minute of the day. The balance of planets to humans is shifting.
Reply | Report Abuse | Link to thisAh...I meant "plants" to humans...sorry
Reply | Report Abuse | Link to thisI don't understand: " but caribou are still calving at the same time, meaning calves are born after most of the food is available, and therefore fewer of them survive." Does this mean to say that most of the available food is gone?
Reply | Report Abuse | Link to thisbalexander,
Reply | Report Abuse | Link to thisNo. Humans and other animals exhale carbon that was taken out of the atmosphere by plants only a short time prior. It's like stirring the pot. Burning fossil fuels is taking carbon that has been sequestered outside of the biosphere for millions of year and dumping it back in. It's like adding more pepper to the pot.
edwmorgan,
Reply | Report Abuse | Link to thisThat's how I understood it. Sounds like the plants grow through a phase and then they are less nutritious or easy to digest. Lots of things we eat are that way; asparagus for example.
Living as I do with two rusty strands of barbed wire between me and the north pole, it is very hard to get exercised about the change in climate as last winter was the coldest one in thirty five years. Sure, I know, I know, climate and weather are not the same thing but as a human being, freezing in the dark as we do here in the winter, is perhaps a NIMBY issue and we might just like a warmer Spring and Fall and extended growing season. I do not think that the polar bear will disappear as they are not unintelligent and to presume that they cannot adapt rapidly is to presume that ONLY humans have the ability to do so. This is not the case. It is the ego of Humans that presume that fact. I suggest that as the sea ice disappears, the polar bear will learn new hunting methods like that of their southern cousins and teach that to their cubs. As to the loss of arctic fox, I suggest that their population will drop but from that failure, mutation pressure will result in a modified fur pattern that allows some to repopulate. Caribou calving I might also suggest might very well be tied to climate and thus might slowly adjust to the earlier Spring. The earth does not stay the same. After meteor impacts, volcanic incidents and so forth, climates have rapidly modified for long periods of time and the flora and fauna have changed either through de-speciation or modifications of the survivors. We are going to for better or worse witness these changes. It is not can it be stopped but rather what will the affects actually be when it happens as happen it will. Who knows really, if opening the Arctic Ocean might instead result in more atmospheric moisture and a rise in snowfall and thus an Ice Age? We humans are the cause of this change but no doubt, such changes caused by creatures on the earth have happened before. Unless you have some kind of Gaia thing happening in your mind, or have a religion, change is what happens and is neither good nor bad but just...IS. In any case, the Earth will be vapourised down the chronological path and none of this will matter any more than if a virtual particle blips in or out of existence near Alpha Centauri. We egotistically think that we and our ecology count for anything. It does not. We do not. Our little activities do not either.
Reply | Report Abuse | Link to thisHaving now read the article, my response is TOUGH S***. Climate change is natural. ALL the ice in Greenland at the GISP2 ice core site MELTED during the last warming spell, because the ice core only has one cycle, as opposed to the Antarctic ice cores.
Reply | Report Abuse | Link to thisTHIS IS WHAT HAPPENS!!! MAN can not stop the natural cycles. Especially when they are caused by the cyclic forces of gravity and NOT by incorrect science attributing it to CO2.
Nothing in nature is static, change is constant...Mankind is no more responsible for the climatic changes today then we were for the warming up after the last ice age that started some 2o,000 years or so ago, and is still slowly continuing.
Reply | Report Abuse | Link to thisGRAVITY, not CO2, causes Global Warming and Cooling.
Reply | Report Abuse | Link to thisThe air has EXCESS CO2. When the sun/solar insolation goes down at night then the amount of the GreenHouse Effect (CO2's delay by catch AND release, not trapping, of photons transported to space,) goes down, thus leaving EXCESS CO2 in the air. When the sun comes up, then more energy transport happens, the GreenHouse Effect (GHE) increases, more CO2 gets used., the temperature goes up. BUT it is the amount of outgoing energy that dictates how much of a GHE there is. The amount of CO2 is irrelevant as long as there is excess. Given that ALL the available (CO2 specific wavelength) energy is already transported by the CO2, then there is NO more available for the so called feedback processes in the global warming models. The excess CO2 must be there to transport energy when it is very hot ,such as summer, or the 49C/120F temperatures during the 2009 Australian bushfires (@385ppm CO2), or the world record 58C (Libya in 1922 -@280 ppm CO2).. So if hypothetically all the CO2 is used up at 58C then there is at least 40% excess today at the world average temperature of 16C/67F according to the Stefan-Boltzmann Law of Physics. Contrary to the IPCC CO2 models, adding more excess CO2 to the air can't cause warming unless you add extra energy. Limiting CO2 emissions by Cap & Trade just removes excess CO2. It will NOT change the temperature.
The real cause of global warming and cooling is the variable gravity/energy from planetary eccentricity as shown in "John Dodds Wobble Theory of Global Warming" (free summary, & full copy available at www.scribd.com).. The forces of gravity cause Earth rotation and winds and tides (moon or lunar gravity) and ocean and liquid core currents and friction and heat. The energy from Gravity is NOT addressed in the GCMs. Gravity also causes the magnetic field by the rotation of liquid core ions through a gravity field. Wind & tide power IS gravity power- where else does the energy come from? The variations in gravity are shown to correlate to the measured ice core temperatures for thousands of years, and to the 60 year cooling/warming cycles from 1880 to 1940 to 1998/9 and to the future 2028 temperature bottom and the 2058 temperature peak. Gravity explains warming AND cooling and is predictable. There will be a gravity spike on Earth in Oct 2010, due to the proximity of Venus and Jupiter. Adding the variable forces and energy of gravity to the Milankovitch Eccentricity (Timing) Theory allows it to overcome it's major deficiency of insufficient solar energy variation to explain ice ages. Gravity explains why the temperature can go up from 1970 through 1998, when the sole source of energy in IPCC models, solar insolation, was essentially constant. Gravity, which is much stronger than sunlight, supplies variable energy to drive warming and cooling. CO2 doesn't.
John Dodds
Nothing in nature is static - change is constant. Mankind is no more responsible for climatic change today then he was over 20,000 years ago when the ice age ended...
Reply | Report Abuse | Link to thisContrary to popular "belief", the last two years have seen cooler arctic temperatures and as much as 8,000,000 MORE square km of unmelted snow cover.
Reply | Report Abuse | Link to thisSpiff,
Reply | Report Abuse | Link to thisAbsolutely right! (But if ego warmed the world, we'd already have palm trees at the North Pole)
I have learned that polar bears
Reply | Report Abuse | Link to thispolar bears survived the most recent interglacial period during which there was no sea ice in the Arctic. The reason polar bears and many other animals are under threat from climate change in today's world is that their habitats are reduced and fragmented due to the actions of homo sapiens, i.e. mankind. Many species cannot survive because their habitats don't have any resilience left
Reply | Report Abuse | Link to thiswow......I was not aware of how much damage the climate's warming was affecting the Arctic!! Not just the animals, but plants also. Also, humans survive off of these animals for survival!! It sounds like it cannot warm up more than 3 degrees or gone! It would be nice to know what to do to help stop the damage besides curb emissions and try to help this serious isssue in the Arctic as best we can help out.
Reply | Report Abuse | Link to thisIt's very upsetting to know that so many animals and plants are not surviving due to weather change and also that humans count on some of these animals for survival. We must do everything we can to help this situation, if possible, ASAP.
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