Please note! This essay has been submitted by a student.
The“Earth is warming, whether it is due to the Earth’s natural cycle or human carbon emissions is up for debate but climate change is affecting Arctic life and that includes polar bears. The Arctic is warming twice as fast as the rest of the world which is impacting all the Arctic, the animals are unable to adapt fast enough to the changing climates. Polar bears are having food shortages, shorter winters and are having more frequent contact with humans as a result of the changing climate in the Arctic, all of which are threatening the species.
Climate change has affected the Arctic more than any other region on earth over the past thirty years. In the first half of 2010, compared to 1996, the temperatures in the Arctic rose seven degree’s Fahrenheit. Due to the temperature changes the arctic has had a decrease in snow cover, ice glaciers began to melt, causing them to retreat, and the ground has begun to thaw causing changes in vegetation. In the Arctic, the ground is secured with snow seventy five percent of the year.
From the use of satellites to researchers and scientists making observations on the ground it shows that the snow spread on the northern side of the equator has showed a significant reduction in the past few decades, especially in the spring. The lessening amounts of snow are generally clear in the spots that are hottest, yet most are typically have snow for parts of the year. The snow spread in the northern half of the globe will continue to diminish through the rest of this century, and could decrease by as much as twenty-five percent by the end of it.
In the Arctic, Alaska and northern Canada are among the territories where icy masses, such as glaciers, have lost the most ice mass over the previous decade. A few pieces of the ice tops have lost mass in the previous two decades, and loss of mass is spreading to new pieces. The pace that the ice is melting at increasing and is expanding. Surface liquefying and calving, which is where large chunks of ice break off the edge of glaciers, together result in about fifty percent of ice loss, both melting and calving are happening more frequently and will continue to do so as the temperatures increase.
A significant part of the land in the Arctic is permafrost, ground that is always solidified because it is frozen. Researchers have used tools and seen it first hand, their observations show that the temperature in the permafrost has increased in many spots over the last few decades. In certain spots, the permafrost is currently four degrees fahrenheit hotter than it was two to three decades earlier. In parts of Scandinavia and Russia, the layer of earth that lies on the permafrost and that defrosts in the late spring, has become as much as eight inches thicker, and there have been significant decreases in permafrost in many pieces of Russia that are usually frozen. The whole territory of the northern side of the equator with surface permafrost is predicted to diminish by as much as seventy-five percent before this century is over.
Ok, so how does all of this affect polar bears? This rapidly changing environment in the Arctic has actually caused many problems for Arctic wildlife, including the polar bear. According to Roz Pidcock scientist predict that “ there’s a 70% chance the global population of polar bears will fall by more than a third within the next three generations”. The changing climate has resulted in a loss of habitat, shortage of food and a longer hibernation period. Polar bears only live in countries that have land in the arctic circle, countries such as the United States, in Alaska, Norway, Russia and Canada. Polar bears a very climate specific animals as they only live in the arctic circle where ice and snow covers the land for the majority of the year. Warmer weather can cause issues for the polar bears such as more disease and collapsing of dens, which can kill their cubs. With snow cover being reduced and the melting of glaciers the habitat suitable for polar bears is becoming harder and harder to find.
The melting arctic also gives the polar bears another issue, a lack of food. The melting ice edges makes it more and more difficult for polar bears to get their main source of food, seals. These seals usually live on the ice’s edge, and this is where the polar bears hunt them, getting the majority of their energy for the year from them. Due to shorter hunting seasons some polar bears have began scavenging for food, which can bring the hungry polar bears into cities and towns and because of their hunger they are aggressive and dangerous toward humans. Food that the polar bears find on land usually does not fit the polar bears diet and as a result they are unable to get the proper nutrients that they need for hibernation. With the lack of food found on land it has become increasingly difficult for polar bears to properly feed the cubs, as a result the cubs are malnourished and are less likely to make it to adulthood.
Hibernation is a very important thing for polar bears, during the winter months when the bears hibernate there is a shortage of food. By hibernating bears use less energy than they would if they were out hunting during the time of year where food is especially hard to come by. If the bears did not hibernate they would ultimately starve to death because they would use more energy than they could consume. To maintain enough energy during their hibernation period the polar bears consume mass amounts of food during the spring and summer months in order to have that needed energy for that extended period of time that they hibernate. With the ice melting more and more during the summer and spring, as previously stated, their main source of food, the seal, is becoming more and more difficult for them to get. With the season for hunting seals becoming shorter and shorter the bears are forced to go longer periods without food which can cause disruptions in their hibernation or cause them to die from starvation.