The monster Arctic storms like we've seen this year have sped up the rate of sea ice loss, but increased water temperatures and air temperatures due to human-caused global warming are the dominant reasons for the record melting of the Arctic sea ice. A July 2012 study by Day et al. found that the most influential of the possible natural influences on sea ice loss was the Atlantic Multi-decadal Oscillation (AMO). The AMO has two phases, negative (cold) and positive (warm), which impact Arctic sea ice. The negative phase tends to create sea surface temperatures in the far north Atlantic that are colder than average. In this study, the AMO only accounted for 5% - 31% of the observed September sea ice decline since 1979. The scientists concluded that given the lack of evidence that natural forces were controlling sea ice fluctuations, the majority of sea ice decline we've seen during the 1953 - 2010 period was due to human causes.

CALL me a converted skeptic. Three years ago I identified problems in previous climate studies that, in my mind, threw doubt on the very existence of global warming. Last year, following an intensive research effort involving a dozen scientists, I concluded that global warming was real and that the prior estimates of the rate of warming were correct. I’m now going a step further: Humans are almost entirely the cause.

There is an overwhelming level of scientific consensus on human-caused climate change. Over 95% of actively publishing climate scientists agree that the earth is warming and that human activity is the cause. In spite of this agreement, only about 50% the general public think that scientists have reached a consensus on human-caused climate change. Two sources of the discrepancy are the unbalanced portrayal of the situation in the media, and the Manufactured Doubt Industry.

We must demand that they acknowledge the reality of climate change, how we are causing it and how it is changing our world, and agree on a path to solve this problem. That path means stopping our contributions to climate change -- a cessation that scientists say is possible only if we can agree, as a society, to change the way we extract and use energy.

The shrinking of the ice cap was interpreted by environment groups as a signal of long-term global warming caused by man-made greenhouse gas emissions. A study published in July in the journal Environmental Research Letters, that compared model projections with observations, estimated that the radical decline in Arctic sea ice has been between 70-95% due to human activities.

The radical decline in sea ice around the Arctic is at least 70% due to human-induced climate change, according to a new study, and may even be up to 95% down to humans – rather higher than scientists had previously thought.

A UN report issued at climate change negotiations in Doha, Qatar, found that human greenhouse gas emissions were triggering the Arctic thaw.

A prominent physicist and skeptic of global warming spent two years trying to find out if mainstream climate scientists were wrong. In the end, he determined they were right: Temperatures really are rising rapidly.

The study of the world's surface temperatures by Richard Muller was partially bankrolled by a foundation connected to global warming deniers. He pursued long-held skeptic theories in analyzing the data. He was spurred to action because of "Climategate," a British scandal involving hacked emails of scientists. Yet he found that the land is 1.6 degrees warmer than in the 1950s. Those numbers from Muller, who works at the University of California, Berkeley and Lawrence Berkeley National Lab, match those by the National Oceanic and Atmospheric Administration and NASA.