Arctic settles into new phase – warmer, greener, and less ice

An international team of scientists who monitor the rapid changes in the Earth’s northern polar region say that the Arctic is entering a new state – one with warmer air and water temperatures, less summer sea ice and snow cover, and a changed ocean chemistry. This shift is also causing changes in the region’s life, both on land and in the sea, including less habitat for polar bears and walruses, but increased access to feeding areas for whales.

Changes to the Arctic are chronicled annually in the Arctic Report Card, which was released today. The report is prepared by an international team of scientists from 14 different countries.

…

Among the 2011 highlights are:

• Atmosphere: In 2011, the average annual near-surface air temperatures over much of the Arctic Ocean were approximately 2.5° F (1.5° C) greater than the 1981-2010 baseline period.

• Sea ice: Minimum Arctic sea ice area in September 2011 was the second lowest recorded by satellite since 1979.
• Ocean: Arctic Ocean temperature and salinity may be stabilizing after a period of warming and freshening. Acidification of sea water (“ocean acidification”) as a result of carbon dioxide absorption has also been documented in the Beaufort and Chukchi seas.
• Land: Arctic tundra vegetation continues to increase and is associated with higher air temperatures over most of the Arctic land mass.

Warning over ocean acidity levels

Large scale “geoengineering” solutions to climate change will not reverse rising acidity in the oceans which damages marine life, conservationists have warned.

The International Union for Conservation of Nature (IUCN) issued a call at the UN climate talks in Durban for countries to urgently address the issue of ocean acidification, caused by greater levels of carbon dioxide in the atmosphere.

The oceans absorb around a quarter of the carbon dioxide humans put into the atmosphere each year, the IUCN said, but the gas dissolving into the seas causes the water to become more acidic.

The IUCN said the acidity of the world’s oceans had increased by 30% since the beginning of the Industrial Revolution, and could continue at an unprecedented rate in the coming decades.

But while ocean acidification has the same cause as climate change – increasing amounts of CO2 in the atmosphere – not all the solutions for global warming will help the situation faced by the seas, the International Ocean Acidification Reference User Group warned.