01-10-2012, 05:51 PM
The Arctic: Thinning by the day
The Arctic.ppt (Size: 1.61 MB / Downloads: 43)
Introduction
Environmental effects on the climate have been going on for centuries, but never has the world been in as much danger as we are now. If we are not careful and don’t take the right precautions the Arctic could thin away before our eyes. In this slide show you will learn about global warming, and climate change and how they are affecting the Arctic. You will learn about what you can do to help preserve the Arctic from thinning away. Finally this slide show will end with a quiz testing you on all the knowledge you have retained from this slide show. Enjoy!
Background Information
What is Climate Change?
Climate change has been occurring ever since the beginning of the planet, about 4.5 billion years ago. It is the long-term affect of the make up of the Earth’s atmosphere, which determines the average temperatures of the planet’s surface. A slight increase or and decrease in the planet’s surface temperature (not weather) makes the difference between an ice age of a hot house Earth. It is up to humans now to control this long term climate change affect. By doing things such as burning fossil fuels (such as coal) and deforestation (the cutting down of trees and forests) we are putting more carbon dioxide into the atmosphere. This carbon dioxide absorbs heat, further increasing the planet’s temperature. The more this continues the higher the surface temperature is going to rise, with more dramatic extremes seen in the Arctic. Studies have shown that humans do not live well on hot climates; high heat works for the times of the dinosaurs. If we are not careful we could wipe the entire human race. Of course the temperature is always going to be rising and there is going to be carbon dioxide and other greenhouse gases in the atmosphere, but humans have the power to speed up or slow down the amount of carbon dioxide in the atmosphere. It is predicted that in the next 50-100 years the earth’s average surface temperature may rise as high as 10 degrees Farenheit due to the rate at which excess amount of greenhouse gases are building up. The predicted rise in temperature will be even greater in the Arctic which would cause the Arctic to melt even faster then it normally would. It could lead to the extinction of animals that thrive and depend on the Arctic ice to survive.
What is happening to the Arctic?
Our Arctic Circle is becoming less by the day. The Arctic is one of the most sensitive places to climate change in the world. As the temperatures in the world continue to rise the effect on the Arctic could wreck its ecosystem and in turn shrink the amount of ice as well as permafrost in this area. By the end of the century there is going to be a 25 degrees farenheight increase in temperature.
In the fall and winters in Arctic Circle there is supposed to be 3 thick layers of ice covering the surface for algae (food) to grow on. This algae is needed so that the food chain ensures survival all the way to the top – so animals (polar bears, seals walrus, arctic foxes etc.) can survive and live. Also those thick layers allow for transportation, shelters, and hunting grounds for these animals. The layer underneath the ice is needed so that fish and underwater mammals can thrive and eat. Since the 1950s the thickness of the ice as well as the amount of water itself has decreased by 3-5 % due to global warming. It is predicted by 2050 the Arctic summers will be so warm that no ice will be present at all. In addition , the arctic stays cold because of the white color of ice, which causes the sun’s rays to get reflected, and makes it hard to the surface to “warm up”. The surface simply can’t absorb heat because it’s too white. The less sea ice we have the more heat is going to be absorbed by the dark colored water, the warmer it will get (feedback from the earth’s albedo). This heat will prevent the Arctic ice from forming since it isn’t cold enough for ice to form. The change in color of the surface from the white of ice, to the dark color of open water amplifies temperature rising, and pushes climate to change even more drastically. This amplifying process is known as feedback and it all comes down to how white is the color of the planet’s surface.
What is evidence that global warming is
affecting the climate and the Arctic?
There is evidence today all over Earth of a rapidly warming climate. Scientists use melting glaciers as evidence for a warming climate. Before the last 50 years scientists paid little, if any attention to ice and glaciers, especially ones in the Artic. In the Artic the thickness has been going down 29% since the 1950s. In addition to all this animals in the Artic are slowly becoming extinct as well. Since the climate is constantly warming the winters in the Artic are slowing disappearing. The ice is not becoming as thick underneath, creating less area for polar bears to roam, and less food for fish to feed off of during the winter (algae growing on the edges of ice – “refrigerated greens” all winter long when there is no sun or photosynthesis. ) If we are not careful the Arctic circle will vanish before our eyes. By looking at the melting rate of ice it is evident that global warming is affecting the climate.