Has the Arctic ice reached a tipping point?

Question

According to James Hansen and The Potsdam Institute for Climate Impact Research in Germany, the Arctic sea ice - which recently shrank by more than 20% below the previous 2005 record low - has reached a tipping point.

"as Arctic sea ice shrinks, the darker ocean soaks up ever more heat than reflective snow and ice...'I'd say we are reaching a tipping point or are past it for the ice. This is a strong indication that there is an amplifying mechanism here,' said Paal Prestrud of the Centre for International Climate and Environmental Research in Oslo."

http://au.news.yahoo.com/070928/2/14jsr.html

Do proponents of the solar global warming theory really believe that this solar irradiance change:

http://www.nasa.gov/centers/goddard/images/content/93617main_sun4m.jpg

Has caused this loss of Arctic sea ice?

http://www.arctic.noaa.gov/detect/detection-images/climate-ice-seaice-extent-trend-sep06.png

http://www.arctic.noaa.gov/detect/ice-seaice.shtml

Answer 1

If you think that's a tipping point, just wait till the Permafrost in Siberia melts releasing all of that centuries old carbon back into the cycle. Or when those frozen ice crystals of methane at the bottom of the ocean melt, releasing a huge amount of methane into the atmosphere all at once.

Answer 2

quicker. fairly nonlinear systems with distinctive helpful feedbacks that are given great helpful perturbations do no longer exhibit various extreme damping of their preliminary reaction. The unfavourable feedbacks which will finally stabilize temperature at stages final considered in the process the PETM won't kick in until after various preliminary heating. you may rationalize this interior the remark that if the unfavourable feedbacks have been instant and massive, there by no skill could have been a warming from CO2 initially. through fact the radiative forcing from CO2 greater suitable, so could the unfavourable comments, offsetting any boost interior the CO2 forcing. that did no longer take place, and the planet has warmed in direct reaction to the forcing from CO2. besides, the reaction of the helpful feedbacks interior the climate equipment have already been pronounced (e.g., boost in humidity, boost in atmospheric methane). I actual have 2 hopes, the two are long photos and that i does no longer positioned money on the two occurring. the 1st is that some unexpected and unknown unfavourable comments arises interior the radiative forcing that gives you an instant, one-to-one unfavourable forcing to the forcing from the greenhouse gases (this would not basically shrink warming, yet shrink any impacts through a redistribution of the worldwide power stability (see word under)). the 2d is that if issues get rather undesirable, which I concern stands out as the case, that Richard Lindzen and something of the depressing skeptics stay long sufficient that they are roundly ridiculed for their scientific malfeasance and lack of expertise.

Answer 3

It's absolutely an important factor. The science is clear. A similar phenomenon is taking place in inland areas, where increased dust storms are darkening snow and ice and increasing the melt rate.

Answer 4

I think the tipping point will be reached when the land permafrost gets unfrozen... and releases its trapped methane and carbon dioxide. Oh boy.

Answer 5

Yea, I wonder how much it cost to have Hansen put his name to that report. I doubt anything Hansen has to say. He's made well over $1,000,000.00 from selling his opinion about global warming. He would have a better reputation if he worked for Exxon.

"20 September 2007 [top]
Overview of current sea ice conditions
Sea ice extent now stands at 4.18 million square kilometers (1.61 million square miles). This represents an increase of 50,000 square kilometers (19,000 square miles) compared to the value of 4.13 million square kilometers (1.59 million square miles) five-day running mean extent, observed on September 16, which appears to be the 2007 minimum."

The ice is growing at a rate of almost 5,000 square miles per day! Only an alarmist or a paid stooge could believe that the ice is still melting.

It's called winter, dude.

Answer 6

Sounds reasonable but I'll have to read more before I make up my mind.

Answer 7

yaaa