Thanks, Turkana. Something needs to be done about this. I think that Hillary Clinton will, along with a lot of her supporters and others who recognize this as the imminent disaster it is. It appears that Bush is as concerned about this as 300,000 people being hacked to death in Darfur.
Anyobe but McCain. Please
Posted by jeter at April 23, 2008 10:00 PMconcerns that the glaciers there are melting rapidly
This is sloppy reporting. Melting at the glacier surface is not what's causing the thinning. What appears to be happening is that a perturbation to the force balance at the downstream ends of these glaciers (Pine Island and Thwaites) has caused rapid speed-up and thus thinning, which is propagating upstream. The perturbation may be the result of increased melting at the seaward ends of the glaciers due to ocean warming or due to increased iceberg calving from the small reaches of floating ice at the downstream ends of the glaciers. Nobody know how far upstream the perturbation will propagate or how large the change will eventually be.
This region, called the Amundsen Sea embayment (because the ice drains into that part of the southern ocean), is the focus of a lot of research during the ongoing International Polar Year. The recent, rapid thinning has been recognized for about a decade but the region is remote and working there is challenging because the weather can be inhospitable. The basic observations are coming together though because the international Antarctic research community thinks it is important to figure this one out.
Posted by Christina at April 23, 2008 10:05 PMI guess you imagine that Obama and his supporters are concerned less about global warming than you Hillarians, eh, jeter? And your basis for this fantasy is.....?
Did the Professional First Lady speak about global warming often during the first Clinton presidency? Guess I missed that.
Posted by euzoius at April 24, 2008 05:37 AMScientists haven't had much luck modeling ice fields - in Greenland they're disappearing much faster than predicted. It's a little scary to have so much uncertainty about when that ice is going to end up in the ocean raising sea levels.
Posted by CA Pol Junkie at April 24, 2008 07:37 AMChristina, I am curious as to your take on the possibility of entering a solar minimum as the sun has been quiet at the beginning of the latest 11 year solar activity cycle. I have been reading more and more articles about this lately and there seems to be a real concern about entering another solar hibernation period. From a piece in Feb posted at IBD about work done in Canada by Kenneth Tapping:
"Kenneth Tapping, a solar researcher and project director for Canada's National Research Council, is among those looking at the sun for evidence of an increase in sunspot activity.
Solar activity fluctuates in an 11-year cycle. But so far in this cycle, the sun has been disturbingly quiet. The lack of increased activity could signal the beginning of what is known as a Maunder Minimum, an event which occurs every couple of centuries and can last as long as a century.
Such an event occurred in the 17th century. The observation of sunspots showed extraordinarily low levels of magnetism on the sun, with little or no 11-year cycle.
This solar hibernation corresponded with a period of bitter cold that began around 1650 and lasted, with intermittent spikes of warming, until 1715. Frigid winters and cold summers during that period led to massive crop failures, famine and death in Northern Europe.
Tapping reports no change in the sun's magnetic field so far this cycle and warns that if the sun remains quiet for another year or two, it may indicate a repeat of that period of drastic cooling of the Earth, bringing massive snowfall and severe weather to the Northern Hemisphere."
http://www.ibdeditorial.com/IBDArticles.aspx?id=287279412587175
This from the Australian:
http://www.theaustralian.news.com.au/story/0,25197,23583376-7583,00.html
"This is where SOHO comes in. The sunspot number follows a cycle of somewhat variable length, averaging 11 years. The most recent minimum was in March last year. The new cycle, No.24, was supposed to start soon after that, with a gradual build-up in sunspot numbers.
It didn't happen. The first sunspot appeared in January this year and lasted only two days. A tiny spot appeared last Monday but vanished within 24 hours. Another little spot appeared this Monday. Pray that there will be many more, and soon.
The reason this matters is that there is a close correlation between variations in the sunspot cycle and Earth's climate. The previous time a cycle was delayed like this was in the Dalton Minimum, an especially cold period that lasted several decades from 1790."
If true, would this not be even more devasting on humans than warming? Are these studies for real or just crackpot deniers? You seem to be more connected with the climate science community and I am curious as to your opinion.
Thanks
Manapp
Here is some more cheery news.
Greenhouse gases rose sharply in 2007. Carbon dioxide is now 385 ppm in the atmosphere.
and
James Hansen's new research suggests carbon dioxide levels need to be reduced below existing levels(pdf) to "preserve the planet". He says 350 ppm. All current global efforts are only aimed at keeping carbon dioxide below concentrations we have not yet reached (e.g 400, 450, 550 ppm, etc.)
Posted by Alvord at April 24, 2008 08:03 AMScientists haven't had much luck modeling ice fields
Not so. We understand the physics of ice flow and can simulate it quite well. There are some fiddly details regarding the numerical schemes used to solve the systems of partial differential equations that describe mass, momentum, and energy balance for ice and different folks have different approaches, a good thing. Where we have some trouble is detailed field observations of all the quantities needed to test the hypotheses we have to explain the current events. These gaps are being filled in to the extent that they can be filled in (but of course this takes time and funding). We'd also like to couple these models to realistic oceans and it would be good to have useful paramterizations to stand in for the details of fracture mechanics (which is important to iceberg calving). Here too, people in the glaciology community are hard at work.
Now, the coupled climate models used for climate projections DO have difficulty with ice sheets. The Fourth IPCC report was quite stern about this, refusing to include contributions from ice sheets in its sea level projections. The trouble here is that the ice sheets in the big CCMs don't flow. They accumulate and lose mass only according to specific mass balance (the annual new accumulation of snow and loss of ice to melting). They don't reproduce the current events in Greenland and elsewhere because they are simply not built to do so. This is a widely recognized shortfall and the big CCM groups are all working on it (and trying to hire ice sheet modelers...there are not very many of us though).
Posted by truffula at April 24, 2008 08:06 AMManapp, I am working on a post about decadal/century time scale solar/cosmic influences on Earth climate but it's slow going given everything else on my plate right now.
The above comment about ice sheet modeling is mine.
Posted by Christina at April 24, 2008 08:11 AMChristina, thanks for the response. I will await your findings. I know my question is off topic regards the discussion of ice sheets melting however in the larger scheme of warming vs cooling it appears that there is much we cannot be certain about. I am concerned of half baked plans to combat warming that will cause more harm than good. Example: the bio fuel/food supply mess. Same applies to the cooling theory as the article points to scientist discussing the release of methane deposits in the oceans via nuclear bombs to help warm the planet. Best intentions have been know to cause really bad side effects.
Posted by manapp99 at April 24, 2008 08:22 AMChristina a.k.a. truffula -
Thanks for your post about ice field modeling. What I've read is that data deficiency is the 800 pound gorilla limiting the modeling - I'm glad the theoretical basis is at least well understood so that an ice field can be modeled well if it were properly parameterized for the model. Correct me if I'm wrong, but I assume the data requirements would require that modeling be done on a small scale and then extrapolated to estimate future sea level rise.
modeling
Data deficiency is part of the problem. I have to go teach a class right now (numerical modeling, go figure...) but this is an important quesiton, CA Pol Junkie, and I'll try to get back to it as soon as I can.
Posted by Christina at April 24, 2008 01:55 PMBut there were two articles in the 1970s in popular magazines that predicted global cooling, so obviously the 2000+ studies by climate PhDs in the past 20 years that predict global warming can't be trusted. I mean, scientists just can't make up their minds. And anyway, it snowed somewhere in Colorado last week. That proves the Earth isn't warming.
/sarcasm off
Sorry for the satire -- I have lost my tolerance for the climate deniers.
Posted by Anonny at April 24, 2008 02:16 PM