Cryosphere: Arctic Sea Ice

Sea Ice along the coast of Wainwright
A year ago I never thought that I would ever be in the arctic. The past 6 months have been an adventure of new experiences and knowledge. Each day I venture out and explore the shoreline and tundra. I have been fortunate to see caribou, snowy owls, fox and ptarmigan. To experience the cold, the wind and extreme changes in weather has given me a new perspective on the cryosphere. Several weeks ago with the temperature hovering around -40F another science teacher and myself hiked on the arctic sea ice. Our objective was to hike out to where there was open water in hopes of seeing wildlife(seals, polar bear). As we walked we observed the changes in the ice. I was thinking wow, I am walking over a frozen ocean. Never had I dreamed of this. The wind blowing, the cold, the ocean currents underneath all added to my wonder of this environment. We never made it to open water, but the lessons of that day provided me one of the best educational experiences on the arctic.
Most people know of the hydrosphere, atmosphere, biosphere, not many think of or understand the influence of the cryosphere. The people of the arctic experience the cryosphere each day. Being from Wisconsin we experience the cryosphere from December through March. The cryosphere includes not only the polar regions but frozen areas outside the arctic. This includes permafrost and tundra at higher elevations, mountain glaciers and winter snow/ice in the mid- latitudes. As the cryosphere changes the other spheres are also affected. Using the cryosphere as a unit theme the disciplines of chemistry, physics and biology would be included. To better understand the cryosphere activities involving ice and solar energy need to be taught. As water freezes it expands increasing the volume and lowering the density. The lower density causes ice to float. Through observation of ice cubes one can see that most of the cube is underwater. As ice melts either in the arctic or Wisconsin will the sea level or lake levels rise? Since ice takes up more space as it melts the new water will fill the space left by the ice and the water level will not rise. Flooding in the mid west is not caused by ice melt but by the melting of the snow. The cryosphere cools the earth. Snow and ice have a bright reflective surface creating a high albedo. Albedo the reflection of heat back into space keeping the earth cool. As ice melts less heat is reflected back and the earth warms. As both snow and ice melt the color becomes darker absorbing more heat and melting more. This type of action is an example of a positive feedback. A darker surface absorbs more heat and will become warmer. On a large scale as in the arctic more exposed water leads to less albedo and more heat absorption and more melting. This is a positive feedback on a planetary scale. As water freezes it loses 80 cal/g dispersing heat to the atmosphere. Freezing is a warming process. As ice melts it requires 80 cal/g, taking heat from the atmosphere, a cooling process. As seawater due to the salt content freezes at a lower temperature. As the water freezes the salt is left behind increasing the salinity of the ocean and increasing the density of the water creating a thermalhaline current. Through this process of ice forming on the ocean the combination of higher density and salinity causes the water to sink to the ocean floor. The sinking of this water creates a current that returns the water to the equatorial regions to be warmed and returned to the poles. These currents will disperse heat and in affect the climate control mechanism. The formation of ice in the cryosphere also affects the biology of the area. Marine animals of the arctic need ice and ice flows for hunting and survival. Ice in Wisconsin also is used by animals for survival and protection.

above right muskrat on ice in Iola,WI

above : seal on ice flow at Hubbard Glacier

As the cryosphere is changing our climate is also changing. The combination of albedo, thinning ice, warming oceans, and the changing of when the ice first forms and leaves will change the native culture. As the changes in the ice occur the hunting techniques will change. The biosphere of the arctic is very fragile. The arctic ecosystem is very productive with a lower biodiversity. If global warming changes the cryosphere animals will have to adapt. Some of the animals of the ecosystem will not survive. As the water warms new species will fill the niches left void by organisms that did not adapt. This will change the food web.

Climate change in the arctic will bring together traditional knowledge and western technology. Using data recorded by natives of the arctic will help western scientists in their quest to learn more about climate and the cryosphere. Traditional knowledge has existed for thousands of years and has influenced the culture. Tapping into traditional knowledge, using satellite technology, making detailed observations and using technology to take a variety of measurements will only strengthen arctic science. The I.C.C. issued a statement to bring the arctic climate problem to the leaders of our world. They stated to stabilize greenhouse gases, have western scientists welcome traditional knowledge, get assistance to the arctic to increase green technology, to recognize the vulnerability of the Inuit people and the arctic to climate change and to help fund changes that will have to be made due to climate change in the arctic.

Whether you live in the arctic or Wisconsin the cryosphere is part of your life. It influences the hydrosphere, atmosphere, biosphere and lithosphere. The cultures of the arctic and Wisconsin are directly related to the cryosphere. Hunting techniques of the arctic rely on ice conditions and any changes in the ice directly effect the native people. The people of the arctic will see the changes much faster in the cryosphere and climate before the people of Wisconsin. The students of both cultures need to think about careers in science. Traditional knowledge and western science will need to combine data and pool resources to continue to understand the earth's cryosphere.

above: Wisconsin snow

left: frozen Chukchi Sea 1.5 mi from land