April 6, 2012
Long-Term Study Sheds New Light On Climate Change Impact
Scientists working on an ongoing study investigating the impact of climate change on various ecosystems have revealed that habitants dependent upon areas that typically experience ice and snow during the winter months are the most threatened by increasing global temperatures.
The finding comes after more than three decades worth of study as part of the Long Term Ecological Research (LTER) Network, a National Science Foundation (NSF) initiative that features more than 1800 scientists and students conducting long term investigations at 26 diverse ecosystems located in the US, Alaska, Antarctica, and islands in the Caribbean and the Pacific. The findings were published Friday in the journal BioScience.
According to an April 6 press release, the research team reported that, as the average temperatures of areas that typically experience winter-time snow and ice increased, a "significant" amount of water that typically enters streams and is used for human consumption and irrigation in semi-arid locales winds up being lost to the atmosphere instead.
"The vulnerability of cool, wet areas to climate change is striking," Julia Jones, one of the lead authors of the BioScience study, said in a statement. "Streams in dry forested ecosystems seem more resilient to warming. These ecosystems conserve more water as the climate warms, keeping streamflow within expected bounds“¦ This research shows both the vulnerability and resilience of headwater streams. Such nuanced insights are crucial to effective management of public water supplies."
The LTER research also discovered that the warming climate is also effecting the cryosphere, the high-latitude regions where water is frozen for at least one month out of the year, in ways experts had not previously realized. A second press release, this one originating from BioScience publishers American Institute of Biological Sciences (AIBS), revealed that it isn't only larger animals such as the polar bear and the penguin that are being affected by climate change.
The article, which was written by Andrew G. Fountain of Portland State University and five coauthors, "describes how decreasing snowfall in many areas threatens burrowing animals and makes plant roots more susceptible to injury, because snow acts as an insulator," the AIBS said. Furthermore, "because microbes such as diatoms that live under sea ice are a principal source of food for krill, disappearing sea ice has led to declines in their abundance -- resulting in impacts on seabirds and mammals that feed on krill."
The disappearing sea ice also appeared to decrease the uptake of carbon dioxide from the atmosphere to the sea, the organization reported, and that changes in the amount of snow on the ground and the melting of permafrost in regions can make these places unsuitable for certain types of plant life, while also reducing the amount of CO2 taken out of the atmosphere by both plants and microbes.
"Shrinking glaciers add pollutants and increased quantities of nutrients to freshwater bodies, and melting river ice pushes more detritus downstream. Disappearing ice on land and the resulting sea-level rise will have far-reaching social, economic, and geopolitical impacts," Fountain and his colleagues discovered, according to the press release. "Many of these changes are now becoming evident in the ski industry, in infrastructure and coastal planning, and in tourism. Significant effects on water supplies, and consequently on agriculture, can be predicted."
The Fountain and Jones studies are two of six resulting from LTER Network research, all of which were published in Friday's special edition of the AIBS journal.
The LTER program was created by the NSF in 1980, with the goal of conducting research on ecological issues over massive geographical areas and extended periods of time, even decades. Annually, the project involves more than 2,000 scientists participating in over 200 large-scale field experiments, with the findings typically being made available to the public for no charge online.
"The LTER sites are providing transformative information about the causes and consequences of climate and environmental changes to ecosystems," David Garrison, the NSF program director for coastal and ocean LTER sites, said in a statement. "These sites are some of our best hopes for providing the sound scientific underpinnings needed to guide policy for the challenges of future environmental change."
Image Caption: Adelie penguins near the Palmer Station LTER site in Antarctica; their numbers have declined. Credit: Zena Cardman