Thread: Real scientists(not propagandists),studying climate changes.

I was just looking over the NASA site, and saw an interesting piece on meaningful study of retreating ice patterns:

http://www.nasa.gov/vision/earth/env...c_minimum.html

And much faster than any of the current models predict.

Perhaps the most worrisome aspect is the strong positive feedback as sun reflecting ice is replaced by open seas.

It has been observed that the trend of declining sea ice production is coupled with an increase in ocean surface temperature and salinity in the Bellingshausen Sea west of the Western Antarctic Peninsular (WAP).

A warmer ocean in the summer leads to less sea ice in the winter.
Less sea ice in the winter leads to a warmer ocean in the summer.

The above statement summarizes the positive feedback mechanism responsible for the decline in sea ice production.

Over the past half century the average annual WAP atmospheric temperature has risen rapidly in agreement with the observed phenomenon of global warming. Naturally, the atmospheric warming has influenced the ocean, such that the ocean has warmed in response.

An important factor governing the region’s oceanic surface temperature is the extent of sea ice. Sea ice acts as an insulator between the atmosphere and the ocean, where less sea ice allows the ocean to warm more readily.

The temperature of the ocean’s surface is of major importance in determining the rate of sea ice formation; high temperatures correspond to low sea ice productivity. Thus a positive feedback mechanism exists: A reduction in sea ice allows for a warmer ocean surface; a warmer ocean surface reduces the ocean’s sea ice productivity.

In the summer when sea ice melts, less dense, fresh and relatively cold water is released forming a stable layer at the top of the water column. The thickness of this layer is determined by the extent of sea ice melting, generally the more sea ice available for melting, the thicker the layer.

Mixing of the upper surface of the ocean will occur; if the upper ocean is composed of a thick layer of relatively fresh, cold water, the mixing will not significantly alter surface conditions. However if the upper ocean is composed of only a thin layer of relatively fresh, cold water – corresponding to low levels of winter sea ice productivity – the mixing will alter the surface such that it is relatively warm and saline. The fact that the more saline water is also warmer, is the important factor in driving the feedback mechanism.

I enjoyed your collection of Younger Dryas materials.

Lynx

Why thank you, although I should note that the Younger Dryas materials are nothing to do with me - it is all the work of our Atmospheric sciences moderator Andre. Good to see that there are people who appreciate the stuff in my forum.

You get polar amplification up in the Arctic (much faster than the southern hemisphere) because of feedbacks like ice-albedo, and the nature of ocean heat uptake.
http://data.giss.nasa.gov/gistemp/

You get more precipitation at both poles (which can lead to accumulation of ice at the interiors of either ice sheet) while sea-ice is lost at a higher rate in Greenland. If you go over the IPCC AR4 (pp 902-908 @ http://ipcc-wg1.ucar.edu/wg1/Report/...Print_Ch11.pdf) they go into detail about what is going on in the polar regions.

The arctic warming much faster is well understood and expected, but if you keep adding CO2 you keep getting more warming globally. The rapid rise of carbon dioxide is more than the slow response time of the oceans can keep up with and you get more solar radiation coming in than infrared going out, and you heat up. A couple of papers:

http://www.acia.uaf.edu/ (this is a big report, but recommended for anything relating to the arctic from geological to climatic to biological patterns)
http://www.atmos.washington.edu/~bitz/HollandBitz.pdf
http://www.springerlink.com/content/6lt5m95y36vd08yd/

P.S. Hi Billiards, I'm very familiar with Andre- we have a lot of academic disagreements (to be friendly) in other forums. I wouldn't be too convinced his views on the paleoisotope are correct, they are very confident in paleoclimatic reconstruction and the topics have been well studied and I'm sure you know he has very deviant views from the mainstream scientific community. We've discussed this a bit more technical in other forums (if you go over to MySpace's Science forum actually) but I won't get into it here.

Chris

Originally Posted by Chris

You get polar amplification up in the Arctic (much faster than the southern hemisphere) because of feedbacks like ice-albedo, and the nature of ocean heat uptake.
http://data.giss.nasa.gov/gistemp/

You get more precipitation at both poles (which can lead to accumulation of ice at the interiors of either ice sheet) while sea-ice is lost at a higher rate in Greenland. If you go over the IPCC AR4 (pp 902-908 @ http://ipcc-wg1.ucar.edu/wg1/Report/...Print_Ch11.pdf) they go into detail about what is going on in the polar regions.

The arctic warming much faster is well understood and expected, but if you keep adding CO2 you keep getting more warming globally. The rapid rise of carbon dioxide is more than the slow response time of the oceans can keep up with and you get more solar radiation coming in than infrared going out, and you heat up. A couple of papers:

http://www.acia.uaf.edu/ (this is a big report, but recommended for anything relating to the arctic from geological to climatic to biological patterns)
http://www.atmos.washington.edu/~bitz/HollandBitz.pdf
http://www.springerlink.com/content/6lt5m95y36vd08yd/

P.S. Hi Billiards, I'm very familiar with Andre- we have a lot of academic disagreements (to be friendly) in other forums. I wouldn't be too convinced his views on the paleoisotope are correct, they are very confident in paleoclimatic reconstruction and the topics have been well studied and I'm sure you know he has very deviant views from the mainstream scientific community. We've discussed this a bit more technical in other forums (if you go over to MySpace's Science forum actually) but I won't get into it here.

Chris

My name there is don jennings, strangely enough, my name. I also have some of my music compositions on my space, donjenningsguitar. I frequent the physics forum a lot. There are so many people there however, the posts get buried rather quickly so you have to keep a close lookout or its gone into the bush of buried posts.