If the Earth was warming, why did the amount of sea ice in the Antarctic increase rather than decrease between 1979 and 2014?
Fact:
It is true that Antarctic sea ice did increase by about 3.5 percent between 1979 and 2014, but it began shrinking again in 2015 and has now reached the lowest level ever recorded. [We don’t have figures for before 1979, as this was when satellite monitoring began.]
One reason for the rise in sea ice levels prior to 2014 is that the winds that blow off the continent increased, carrying more cold air out to sea, where ice forms. Another reason is that increasing meltwater from the Antarctic ice sheets led to an increase in ice formation, as fresh water freezes at a higher temperature (0°C) than salt water (-2°C). Finally, higher temperatures increased the amount of snowfall over both the continent and the surrounding oceans, thereby increasing sea ice cover. [This is because warmer air holds more moisture.]
The problem, however, is not the loss of sea ice in Antarctica but the loss of land ice. Between 2002 and 2025, that loss averaged 135 billion tonnes a year, causing sea levels to rise by 0.4 millimetres per year. The science suggests that the rate of loss is only going to increase as the Earth’s atmosphere heats up. [It takes approximately 360 billion tonnes of ice to produce one millimetre of global sea-level rise.]