2010-09-29 09:09:05A wrinkle in Antarctic sea ice
John Cook


I haven't got around to updating the Antarctic sea ice rebuttal with the new research from Judith Curry which suggests more snow insulates the sea ice. But one of the proposed factors is depleted ozone which causes cyclonic winds which increases polynas which leads to increased sea ice production.

However, a new paper models sea ice extent and suggests depleted ozone should decrease sea ice, not increase it. Will need to update my rebuttal:

Has the ozone hole contributed to increased Antarctic sea ice extent?

Since the 1970s sea ice extent has decreased dramatically in the Northern Hemisphere and increased slightly in the Southern Hemisphere, a difference that is potentially explained by ozone depletion in the Southern Hemisphere stratosphere. In this study we consider the impact of stratospheric ozone depletion on Antarctic sea ice extent using a climate model forced with observed stratospheric ozone depletion from 1979 to 2005. Contrary to expectations, our model simulates a year-round decrease in Antarctic sea ice due to stratospheric ozone depletion. The largest percentage sea ice decrease in our model occurs in the austral summer near the coast of Antarctica, due to a mechanism involving offshore Ekman sea ice transport. The largest absolute decrease is simulated in the austral winter away from the coast of Antarctica, in response to an ocean warming that is consistent with a poleward shift of the large-scale pattern of sea surface temperature. Our model results strongly suggest that processes not linked to stratospheric ozone depletion must be invoked to explain the observed increase in Antarctic sea ice extent. 

Is it just me or is there a helluva lot of climate papers coming out in the last few weeks?


2010-09-29 09:19:57comment
Robert Way

Yeah it really does seem like there was. But the thing is there are always lulls... I thought I felt a big lull for a while and now its a complete blitzz at the wrong time.
2010-09-29 12:31:51


Greg Johnson emphasized to me to importance of not underestimating the influence of the Southern Annular Mode, which is apparently adjusting not only to warming up north but also the influence of ozone depletion. He also went through a monologue of about 3 minutes' duration rapidly listing off the confounding influences on water circulation in the vicinity of the Antarctic, with more to follow as I desperately came up for air trying to ask some questions. The man's a walking encyclopedia, each question inviting a firehose of information.

I'd be cautious about under-damping your updates on Antarctic ice, unless something morphs into the latest change of hemlines in the skeptic fashion world.  

Some background info on SAM here http://www.atmos.colostate.edu/ao/introduction.html 

A lot of things come together at the poles of rotating unevenly heated hydro and thermo dynamical collisions, manifesting themselves in strange ways; I'm drawn to think about the odd hexagon found at Saturn's north pole.


2010-09-29 12:42:36Greg Johnson's monologue
John Cook

Sounds like it would've been a great conversation to have been part of. Why don't I have some brilliant ocean expert in my neighbourhood? Well, actually, there is Ove Hoegh-Guldberg. In fact, my conversations with him sound a lot like yours with Greg - densely packed with information with me nodding thoughtfully as I try to keep up.
2010-09-29 13:42:22


...nodding thoughtfully...

For me the conversation was a bit of a game-changer, crystallized my dawning recognition that all I can do is to be a reasonably faithful, attenuating and filtering but not distorting conduit between the work and popularization. Nothing intelligent for me to add, sadly, far too much fractal detail behind the paper.

Digesting studies of London and weaving them together with historical figures and political influence peddling is one kind of fun, this straight transmission thing is something else entirely.  

2010-09-29 17:08:47
Ari Jokimäki


The full text for this study:


2010-09-29 17:55:27Game changing revelation
John Cook


I had a similar revelation, only years ago :-) Early in Skeptical Science history, I considered doing some peer-reviewed research into how cosmic rays couldn't be causing global warming. Eventually I decided the best use of my time was to concentrate on translating peer-reviewed science into plain English for the general public. Let the scientists do the science and the blogger do the blogging.

Ari (aka the paper whisperer), thanks for the link. Have copied the full paper to my iPad for some relaxed reading on the couch tonight :-)

2010-09-29 18:32:35contextualizing


is also an extremely important service. The reason this material needs to be popularized is not just because it is technical, but because the important implications and/or assumptions are not clear to the typical reader.

SkS is not in the business of finding new scientific facts, but in the enterprise of transmitting what is truly important - and why.