Scientists confused by changes in ice extent in the polar regions
Most scientists seem to be confused by the increasing ice extent in the Antarctic region. Some say this phenomenon disproves climate change models and the validity of global warming. According to a new study by the National Center for Atmospheric Research, the unexpected increase is called “Interdecadal Pacific Oscillation (IPO), a natural mode of climate variability.” This latest theory essentially means that nature is doing this all by itself. http://nsidc.org/arcticseaicenews/
But there’s a better explanation that indicates the human factor is involved. Atmospheric greenhouse gas levels have been increasing constantly for at least 70 years, without a doubt. This allows the atmosphere to trap more thermal energy during the day and release thermal energy more slowly during the night. It also means moisture (as steam) can travel for longer and further in the interacting wind and jet-stream systems than before. More moisture is going up from the warmer regions of the northern hemisphere but average annual rainfall has not increased much if any. Because the atmosphere is a closed system, more moisture that goes up somewhere must come down somewhere. Increased thermal energy that traps steam in the atmosphere prevents an increase in annual rainfall in all parts of the earth except in the coldest regions, namely the South Pole. The sea at the North Pole provides a moderating effect on temperature variability. In contrast, the South Pole is a continent. The freeze is virtually permanent and so moisture in the atmosphere precipitated as snow or ice in the south is trapped there more so than in the north. The South Pole is the coldest part of the earth and acts like a moisturer trap more successfully than at the North Pole where sea currents help warm and melt floating ice.
So a definite change is taking place irreversably and soon the North Pole will lose most of its ice as a result of rising greenhouse gas levels. Then the northern hemisphere will really experience global warming like never before, while the south will lag behind the temperature trend probably by several years.
Atmospheric greenhouse gas levels have been increasing in proportion with growth in global population and energy use and pollution, These trends all correlate perfectly so it’s almost certain that the human factor will eventually be recognized as the cause of the observed changes in the polar regions.