Arctic Sea Ice Volume Anomaly
Sea Ice Volume is calculated using the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) developed at APL/PSC by Dr. J. Zhang and collaborators. Anomalies for each day are calculated relative to the average over the 1979 -2009 period for that day to remove the annual cycle. The model mean seasonal cycle of sea ice volume ranges from 28,600 km^3 in April to 13,400 km^3 in September. The blue line represents the trend calculated from January 1 1979 to the most recent date indicated on the figure. Monthly average Arctic Ice Volume for Sept 2010 was 4,000 km^3, the lowest over the 1979-2010 period, 78% below the 1979 maximum and 9,400 km^3 or 70% below its mean for the 1979-2009 period. Shaded areas represent one and two standard deviations of the anomaly from the trend. Updates will be generated at approximately two-weekly intervals.
Polar Science Center - APL-UW - Arctic Sea Ice Volume
I don't think that anyone doubts that the globe warms. I think associating human activities with it is a bit arrogant of us has humans. Should we clean up our act? sure. Should we find alternative fuel sources that create less polution? Yes. Have people caused global warming? Doubt it.
Brian, events do not occur in a vacuum. Something causes them. Several times in the geological past we have seen rapid warming as the result of rapid increases in GHGs. Those were caused by volcanic events. Today, the rapid increase of GHGs in the atmosphere is caused by humans burning fossil fuels. However, that does not matter in the least as far as the physics of the situation is concerned.
Whatever the source of the GHGs, the result will still be rapid warming. The link I gave you was the the American Institute of Physics. The information is written by physicists. Real scientists currently practicing their profession.
The problem with AGW theorist is that they change their evidence from year to year. "Oh wait, that was wrong, but it's actually this." We saw this in the IPCC when they published a report with the Mann hockey stick graph, and then withdrew it in the Fourth IPCC report because Mann had manupulated information and left out key time periods in our history.
As far as Volcanoes and such, we have NO way to prove that. Sure, Geologist can look at the rocks and make an educated guess at what was going on, but I doubt roaches were running experiments on GHGs in the atosphere.
I guess my point is that there is SOOOOO much, especially in the scientific community that we don't know about the earth. Thr problem is when we assume that we know everything. The other planets in our solar system are warming as well, how is this explained???? I'm sure some AGW theorist has come up with specific reasons why each planet is warming, therefore disconnecting it with Earth's warming.
Like I said before, I have no problem cleaning up our act, but I won't believe AGW until it's proven.