Tuesday, April 24, 2012

The Cryosphere: The Earth's Frozen Realms

What is the cryosphere? The cryosphere is any part of the Earth that consists of frozen water. This includes snow, ice caps, glaciers, sea ice, and permafrost. Without your knowledge these things have been working hard to provide ecosystem services such as water storage and increasing the Earth's albedo, or the reflectivity of the Earth. But we have also taken a toll on how well these ecosystem services function. This is a cause for concern because a world with a damaged cryosphere means a world with much more water and a lot higher temperatures.

How is this happening and what can we do to stop it?

The issue is global climate change. Human-caused climate change is greatly decreasing the amount of snow and ice, especially in the Northern hemisphere. As temperatures increase, ice and snow melt increases, replacing reflective snow with heat absorbing dirt. This creates a positive feedback loop as a darker Earth absorbs more heat and increases global warming even more. The albedo is an important ecosystem services that the cryosphere provides.

This figure shows the global temperature increases. The greatest increase occurs in the north. This can be partially attributed to the decrease in albedo in this region.

As ice caps melt, an excess amount of water becomes available. No longer frozen and stored, this leads to a rise in sea level. If all the glaciers were to melt today the sea level would rise a reported 230 feet (NSIDC). When water melts it also expands. This is why the cryosphere is so important. It holds water much more efficiently than oceans and lakes. As we lose this efficient storage, we have a rise in sea level because of the ice melting, and also because as the water heats up it expands. A loss of these storage systems would also have negative effects on supporting ecosystem services as well. Snow and glacier melt provide water for agriculture and drinking water as well as recharging aquifers. This becomes increasingly important as water is consumed at higher and higher rates on a global level.

Many scientists are studying the changes currently going on in the Arctic. The melting of ice sheets and decrease in snow levels year after year can be plainly seen in figures such as the one below. It is no longer a question of whether or not loss of ice caps is an issue, it is how long do we have and what are we going to do.
The extreme recession of the Greenland ice sheet. Glaciers, ice caps, and seasonal ice are good indicators of environmental change as they react quickly when effected. If loss of these resources is the first thing to happen, what else is to come?
Ted video by James Balog who studies ice-loss. The best visuals start around 7min in, but overall a good explanation of the issue.
This video has some beautiful visuals that highlight the cultural value of the cryosphere. While glaciers and snow are important for ecosystem services, they also have an intrinsic value. Even if you do not dream of ever going to the poles, you probably still enjoy skiing or hiking snow-capped mountains. No one wants to damage this resource and yet we are knowingly doing so every day. Sadly, the intrinsic value of the cryosphere is not enough to save it. It is possible that we need to put monetary value on it if we are to slow it's decline.

What are we going to do? Snow and ice provide key ecosystem services that we currently ignore. One group is suggesting that we give Arctic sea ice an economic value. Do you think that will work? What value would you give the cryosphere? What other values other than ecosystem services do you think ice and snow have?

Increasing Earth's albedo by changing how we build is one viable option. This can be done with reforestation, decreasing the amount of pavement, and by installing reflective or white roofs. It is possible that this could help slow the loss of ice and snow, but it will not be enough if we continue living as we do.

Daily (2009) argues that we need to monitor and give value to ecosystems services so that the individuals, corporations, and governments that create the problem will pay the price of the damage. To do this she proposes the Natural Capital Project, which uses a value system for ecosystem services to aid in policy and decision making. This project uses stakeholder involvement to find realistic alternative scenarios for the future. Daily argues that first of all the science of ecosystem services needs to increase rapidly and that "ecosystem services must be explicitly and systematically integrated into the decision making by individuals, corporations, and governments"(Daily, 2009). Daily acknowledges that price alone will not completely solve the problem, but that it will help people stop discounting the future. You can read more about the Natural Capital project here.

This figure shows how the Natural Capital Project gives value to ecosystem services. It considers all the types of ecosystem services; provisioning, regulating, cultural, and supporting. This model also considers biodiversity of species and habitats.

Now that you know what the cryosphere is doing for you what are you going to do for it?

"Ecosystem Services of Arctic Sea Ice Need Urgent Economic Valuation." PRWeb. Vocus PRW, 3 June 2011. Web. 18 Apr. 2012. <http://www.prweb.com/releases/2011/6/prweb8525893.htm>.

Daily, Gretchen C., Stephen Polasky, Joshua Goldstein, Peter M. Kareiva, Harold A. Mooney, Liba Pejchar, Taylor H. Ricketts, James Salzman, and Robert Shallenberger. "Ecosystem Services in Decision Making: Time to Deliver."Frontiers in Ecology and the Environment 7.1 (2009): 21-28.

"Facts about glaciers." National Snow and Ice Data Center. Web. 21 Apr. 2012. <http://nsidc.org/cryosphere/glaciers/quickfacts.html>.

Guitarfreakg290. "Planet Earth Sigur Ros Glosoli." YouTube. YouTube, 16 Oct. 2007. Web. 18 Apr. 2012. <http://www.youtube.com/watch?v=4HqcjgJCDuw>.

"James Balog: Time-lapse Proof of Extreme Ice Loss." TED: Ideas worth Spreading. Web. 18 Apr. 2012.<http://www.ted.com/talks/lang/en/james_balog_time_lapse_proof_of_extreme_ice_loss.html>.

"Global Outlook for Ice and Snow." United Nations Environment Programme (UNEP). Web. 21 Apr. 2012. <http://www.unep.org/geo/geo_ice/>.

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