Climate Change and Antarctica
Climate changes in and around Antarctica have been comparatively less pronounced to date than climate induced changes around the Arctic region.
| Related Resources West Antarctica Ice Sheet Climate Change Articles |
The General Circulation Models (GCMs) used for climate forecasting basically conclude polar regions will experience the most pronounced temperature increases.
Today, many of the more visible examples of changing climate patterns are found in the northern polar regions.
In its 2007 Fourth Assessment, The Intergovernmental Panel on Climate Change (IPCC) reported that "The Arctic is very likely to warm during this century in most areas, and the annual mean warming is very likely to exceed the global mean warming." Scientists at the National Snow and Ice Data Center have been providing strong correlative evidence supporting the warming Arctic expectations of the IPCC. An October 2007 report on Arctic Sea Ice, for example, shows sea ice declines ranging between thirty-nine and fifty per cent in that past couple of decades, depending on which measurement tools are used.
As a large land mass surrounded by the world's oceans, Antarctic geography often is described as the polar opposite of Arctic geography. Because approximately ninety per cent of the world's ice is found on and around Antarctica, global concern about climate change and Antarctica deal with potential sea level rise associated with glacial melt.
The IPCC reports some weaknesses in the GCMs abilities to adequately forecast long term Antarctic climate trends. "A serious problem is the lack of observations against which to assess models, and for developing process knowledge, particularly over Antarctica."
Currently scientists have only an adequate understanding of the regional factors historically influencing Antarctic climate conditions. Most regional Antarctic climate studies are organized with both an ocean and an atmospheric element.
The Antarctic Circumpolar Current, the strong ocean current that encircles the continent, moving in a clockwise direction, serves as the primary ocean explanation influencing Antarctic weather patterns.
The current connects the southern parts of the Atlantic, Indian and Pacific Oceans with the Antarctic Ocean. Weather conditions in Antarctica are partly dependent on weather factors in three of the world's oceans.
The presence of an El Nino in the Pacific Ocean, for example, not only affects United States weather patterns, but also affects weather patterns in West Antarctica. (see NASA Study Links El Nino and Southern Ocean Changes)
Ozone depletion serves as a regional atmospheric factor affecting Antarctic climate conditions. Thus far, the increasing temperatures that are suppose to come to Antarctica with global climate change have been limited to a few areas, mostly around the Antarctic peninsula in West Antarctica. Scientists have been using a working hypothesis that ozone depletion over Antarctica creates stronger continental wind patterns. These wind patterns have in turn helped moderate temperature changes across East Antarctica. (British Antarctic Survey - Climate Change and Antarctica)
The area in West Antarctic adjacent to the Amundsen Sea is one region where glacier melt has been studied, and appears to be accelerating. A panel of Antarctic scientists recently met, Secrets of the West Antarctic Ice Sheet: A Panel Discussion About Global Warming, Climate Change and Rising Sea Levels, to discuss the issue. The scientists on the panel present a balanced short and long term history of climate patterns in the Amundsen Sea region.
Their power point presentations were not totally recorded on the video. When they are discussing glacial patterns in specific regions, it's important to have a map knowledge of the area they are discussing, in order to keep up with the discussions.
© 2007. Patricia A. Michaels.