If the world warms up, there should be less ice, right? On the whole this statement appears to be true, but global warming can actually cause some areas to cool. Right now, it appears that changing weather patterns are causing ice levels in Antarctica to increase, even as ice is melting in the Arctic.
NASA has concluded that ice in Antarctica isn’t shrinking, just the opposite, it has actually expanded to record levels. In fact, the ice shelves have expanded to their largest size since scientists began to use satellite imagery to measure the overall size of the ice.
NASA has warned, however, that while Antarctica is slowly expanding, it is not expanding rapidly enough to offset the massive losses in the Arctic ice shelves at the north pole.
The arctic sea ice, however, has reached its lowest winter maximum in history. This means that the total cap of ice found at the North Pole has shrunk considerably. The cap now measures only 5.61 million square miles, 50,000 square miles below the previous low, which was set in 2011.
NASA provided the following statement:
Since the late 1970s, the Arctic has lost an average of 20,800 square miles (53,900 square kilometers) of ice a year; the Antarctic has gained an average of 7,300 square miles (18,900 sq km). On Sept. 19 this year, for the first time ever since 1979, Antarctic sea ice extent exceeded 7.72 million square miles (20 million square kilometers), according to the National Snow and Ice Data Center. The ice extent stayed above this benchmark extent for several days. The average maximum extent between 1981 and 2010 was 7.23 million square miles (18.72 million square kilometers).
Interestingly, global warming may still be the root cause of the expanding ice in Antarctica. Changing weather patterns could be sending cooler air to the south.
One theory suggests that a low-pressure system that is centered in the Amundsen Sea is growing stronger, or becoming more frequently. If so, the system could be sending warm air to the Antarctic Peninsula, where temperatures are rising, but pushing colder temperatures into the Ross Sea and elsewhere where ice is growing.
The jury, however, is still out on what is causing ice in the Antarctic to expand. While expanding ice may help reduce the effects of global warming by stabilizing water levels, and contributing elsewhere, NASA is already warning that the expansion is not enough.
Besides a growing Antarctica, global warming may also create harsher winters, at least in some locations. How can this happen? One possibility is for increased melting of Arctic ice in the northern hemisphere can create warmer summers with more moisture. These warmer summers, however, can result in more snow in some areas, such as Siberia. As snow piles up earlier in the winter, this helps chill the rest of the winter.
All in all, these instances suggest that global warming is a complex system, and can produce surprising results in some cases.
If ice levels continue to decline on the whole, however, oceans could rise. Ice is more compact than water, so as the ice melts, the total volume of water increases. Eventually, these rising waters could overwhelm low lying areas.