Arctic Sea Ice Extent and Volume Follow Long-term Trend

Sea ice expands and contracts in the Arctic and Antarctic with the seasons. The maximum extent and volume is usually in March, while the minimum occurs in September. Although there have been annual fluctuations, Axel Schweiger  gives a brief interview about evidence that the volume of Arctic sea ice has been on a downward long-term trend based on PIOMAS (Panarctic Ice Ocean Modeling and Assimilation System) data.