Ice Caps Melting The Ice Caps Melting Are global warming and the greenhouse effect causing the ice to melt and the sea levels to rise Antarctica and Greenland hold a good population of the worlds ice in the ocean. The article, Answers to sea level rise locked in ice by Jack Williams of USA Today, describes what is happening with the polar ice caps, and how it is going to effect the world. Williams compares the amount of ice in Antarctica to the size of Usa 48 contiguous states and half of Mexico. Antarctica is a total of 5.
4 million square miles. It has 91 percent of the worlds ice and 70 percent of the globes fresh water. The worst-case scenario would be all of Antarctica ice melting, which would raise the sea level by about 200 feet. However, Antarctica is not said to become warm enough to do this for well over hundreds of years. Antarctica has two main sheets of ice that would pose a threat to the world: the West Antarctic Ice Sheets and the East Antarctic Ice Sheets.
Together the East and the West ice sheets hold about 91 percent of the worlds glacial ice. The west Antarctic ice sheet is south of the Pacific Ocean, and holds 11 percent of the ice that sits on the continent, and is mostly below sea level. Therefore, the west Antarctic ice sheet poses a bigger threat than the East because the Wests bottom is mostly below the sea level. Every year ice spreads through Antarctica and moves towards the edges. The ice from the West Antarctic sheets moves mostly onto the Ross and Ronne ice shelves, which are floating on the ocean. Williams says that if the shelves melt, it will cause large parts of the ice-sheets to break off and melt into the sea.
If the two ice sheets should melt the sea level would rise 200-260 feet. This would end ange a large portion of the population and reshape the worlds coastlines, as well as change the worlds temperatures. The ice works as a cooling source for the world without it the summers would be increasingly hotter. There are many scientists working in Antarctica trying to figure out how long it will be for the ice sheets to collapse. There are satellites that can determine the location of the ice and the ices pattern of movement. Drills are also being used to look at the ice from the bottom up.
This method allows the scientists to see any changes in the ice due to the weather patterns that have occurred over thousands of years ago. By studying these previous changes, scientist can use their findings to make future hypothesis on the pattern of the ice sheets. Is there more or less ice And how much more or less It was found that the ice sheets are losing ice from around its edges. However because of the constant snowfall and low temperatures, there has been neither large-scale gain nor loss of ice. The main reason that the ice glaciers of the world would melt is do to the increasing temperature of the world.
These increasing temperatures are caused by global warming and the greenhouse effect. Technology and human activities such as the burning of coal and oil raise the level of heat trapping gasses. It is said that the twentieth century has been the warmest century in time do to the increase of these human activities and if it continues to go on like this there is no doubt that it will contribute to the melting of the ice caps. There are too many people and too limited natural resources. Experts have said for some time that a warming atmosphere has caused many mountain glaciers around the world to shrink, found William Stevens of New York Times.
Greenland, the second largest land covered with ice (Antarctica being the first), is having the same problems with losing its ice. These ice sheets cover 85 percent of the island. In Greenland snow falls all year long and the temperature rarely rises above freezing, so almost none of the snow melts. The mountains, which surround most of the coast of Greenland, block the ice from reaching the sea. After many experiments scientists have discovered that Greenland is losing ice around the edge of the ice sheets (USA Today). The melting of ice in Greenland has not been as intensely studied as the melting of ice in Antarctica, so at this point it is too soon to make any conclusions about Greenlands patterns of melting ice.
Since there has been no past data on Greenlands ice sheets to compare, scientists cannot truly determine whether or not the ice sheets are melting more or less now than in the past. The current studies have not been conducted for a long enough period of time to distinguish between long term and short term possible effects. As technology increases there are more ways to study the ice sheets. In the fall of 2001 NASA plans to launch ICES AT, which will make measurements of the ice sheets in both Greenland and Antarctica with lasers. This is similar to the way the ice sheets have previously been measured, except with satellite instead of an airplane.
The satellite should be more effective because it can cover a larger area and make measurements more often than an airplane can. Kra bill, a scientist working on the ice sheets, is convinced, as many other scientists are, that it is due to global warming (NY Times, 13). It is true that the ice sheets are losing ice, but at the same time they are gaining it back because of the water that evaporates in the air, mixing with hot air and creating new snow fall. Although the melting would not affect humans for over more than a hundred years, it is good that studies are done now to try to prevent the problem from happening. Scientists are constantly studying the ice in order to prevent the melting. Hot water drills are used to make a hole in the bottom of the ice so that the ice can be studied.
By studying the make-up of the ice, it can be determined what previous effect the weather has had on the ice. The chemicals that make-up the inside of the ice tells the history of the ice. The ice first began as snow and over the years has become an enormous mass of ice. By learning about the past transformations of the ice we can predict what will happen in the future due to weather changes and possible global warming.
There are scientists that believe that global warming is not occurring and if it was it could be a good thing. Their studies show that the ice caps are not melting at all, but instead growing, and that melting could only occur during the polar summer, not the polar winter. They also say that the only time in which the temperatures have been warmer where times in which the melting of the ice could not occur. Even though the vast new research may prove them wrong, other scientist still believe global warming has and will continue to occur because of the past and present data and the scientific analyses they have. Research on the melting of the ice caps and global warming will continue, however with more and more new developments contradicting the theory it is getting harder to believe that global warming will effect the ice sheets. Both theories can be argued, but unless proof is obtained on whether or not the ice sheets are shrinking, it is harder to believe that global warming is affecting the ice.
The launch of NAS As satellite next fall should shed truth onto this topic. With temperature so low in Greenland and Antarctica it seems easy to believe that new snowfall will replace any ice that melts, thus not allowing the sheets to shrink. However with rapid temperature increase, or global warming, snowfall will decrease and the ice will melt. So far this has not happened.
The ice appears to be replenishing itself, so at this time there is no impact due to global warming. Future generations may have to deal with the possible effects of global warming on the ice sheets, but until there is proof that the ice sheets are melting, it is hard to determine what the effects will be if any. Research will continue to untangle the mystery of global warming and its effects on the ice sheets. Jeffreys, Kent 1991 Why Worry About Global Warming web Stevens, William K. 1999. Surveys Uncover Substantial Melting of Greenland Ice Sheets.
New York Times, NY, Mar 5: pg. 13. Williams, Jack. 1999. Answers to sea level rise locked in ice. web Williams.
1999. Studies confirm Greenland is losing ice. web >.