Saturday, September 18, 2010

Arctic Sea ice extent not ready to call its melting quits yet -- looks like we have a double dip

Dear Readers,


It is little discussed, but in general the planetary water vapor streams eventually carry the energy from hurricanes and typhoons up to the Arctic Sea. Typhoon energy goes up through the Bering Strait. Naturally, if they make landfall, a lot of energy is dissipated, but if they do not make landfall, then it usually ends up in the far North.


This year, China was hit with 10 typhoons already, and I don’t know how many did not reach land but were just sucked up to the Arctic Sea, instead, much like in 2007.


Looks like another one is set to hit China:


http://cimss.ssec.wisc.edu/ tropic/ real-time/ mosaic/ movies/ moswwvbbm/ moswwvbbmjava.html


Since I tend to watch the Univ. Wisc. WV satellite animations nearly every day, and could see this occurring, especially over the past few weeks, I am not at all surprised that there was a double dip.


This link shows the entry to the Bering Strait better, but nothing of note is occurring today — if you look at it regularly like I do, then you begin to get a sense of how the energy is transported. 


http://weather.unisys.com/satellite/sat_wv_hem_loop-12.html


If the energy were not continuously transported away from the Equator and toward the poles, the temperature at the Equator would be much higher and that of the poles much lower. 


However, what is really more important is the sea ice volume, not the extent.  The Polar Ice Center's graph of Arctic ice volume shows that this summer there was a precipitous decline (well out of the 2 SD lower limit) and then some recovery -- we need to watch that graph to see if there is going to be a further dip in volume this year (please click on the graph to enlarge it):




I'm gonna add some comments here since blogspot is telling me my comment is too long!


This one is for ljgeoff:

Loss of Summer Sea Ice -- Impacts

First, an interesting look through the eyes of the native Inuits is provided in Dr. Heidi Cullen's recent book, "The Weather of the Future."

If you do not have access to the book, there really is a huge list of impacts, and lots of research on all of them.

Here on this blog, for example, there are tons of articles on melting permafrost.  If you look at a map of northern Siberia, you can see that it was once an enormous flood plain or marsh running up to the edge of the Arctic Sea, which is not all that deep there.

That land and sea will warm rapidly when there is no ice cover, releasing untold quantities of methane.

Cullen points out that when there is ice cover, the air is much cold and drier.  Further, the warmth in the water below the sea ice is not transferred to the air.  We know that the water's temperature is increasing.  Take away the ice cover and the energy gets transferred from the water to the air pretty quickly.

The Inuit say that the ice does not form now like it used to because of clouds.  It's one of those positive feedbacks (remember: a positive feedback means more warming).

We can also expect the winds passing over this open water that reach Greenland to cause the Greenland Ice Sheet to melt faster because they will be warmer and wetter than if they had passed over sea ice.

I am not exactly sure, but the changes in the monsoon over the U.S. Southwest may not be as affected by the lack of sea ice in the Arctic as it is by the huge amount of heat pumping out of the Pacific Ocean at the Equator.

The thing that I think no one really knows is just what exactly the new weather patterns will be over the Arctic once the sea ice is gone and it is quite warm up there. Well, actually, I think the modelers have done the model runs but they just don't want to tell us yet.  But let me put it this way (very simply) -- there used to be this cap of cold air that hung around the North Pole, and the hot air from the south has been pushing that cold air out of the Arctic, and just weakening it, and reducing it.  Eventually, there won't be a lot of it left.  What is that going to do to weather patterns in the Northern Hemisphere? I'd venture to say that they won't be anything like what we have been used to for hundreds of years.  How on earth a farmer will be able to tell when to plant crops is beyond me.

Tenney


by Joseph Romm, Climate Progress, September 18, 2010

So the fat lady sang, but I guess she hit just the right note and  shattered some more ice.  Or it could be those pesky greenhouse gases, which  always seem to be causing trouble…


http://www.ijis.iarc.uaf.edu/seaice/extent/AMSRE_Sea_Ice_Extent_L.png

That plot is from the Japan Aerospace Exploration Agency (click to enlarge), whose latest value for sea ice extent (yesterday) is 4,832,813 km2.  There  appears to be a real chance JAXA’s extent will drop below the 2008 level.

Their data for the last ten days shows how sharp this new downturn is:


09,07,2010:  5027188
09,08,2010:  4989375
09,09,2010:  4972656
09,10,2010:  4952813
09,11,2010:  4986406
09,12,2010:  5005000
09,13,2010:  5008750
09,14,2010:  4998594
09,15,2010:  4948438
09,16,2010:  4890938
09,17,2010:  4832813

You may have  noticed that  the National Snow and Ice Data Center, which called a minimum a few days ago,  doesn’t show a full double dip (yet):
http://nsidc.org/data/seaice_index/images/daily_images/N_stddev_timeseries.png

That’s in part because they use a different metric.  As JAXA explains:
In general, sea-ice extent is defined as a temporal average of several days (e.g., five days) in order to eliminate calculation errors due to a lack of data (e.g., for traditional microwave sensors such as SMMR and SSM/I). However, we adopt the average of two days to achieve rapid data release. The wider spatial coverage of AMSR-E enables reducing the data-production period.
NSIDC uses the less volatile five-day average, which  bottomed out, for them, on  September 10 at 04.72 h.  As of  yesterday, they  tell me they haven’t  passed that — yet.

The sea ice area  picture seems a little muddier:

http://www.ijis.iarc.uaf.edu/seaice/extent/AMSRE_Sea_Ice_Area.png

I can’t find  the actual data for this plot.  If  anyone knows where it is, please post the link.

NSIDC told me that as of Wednesday, it’s “only in the E. Siberian Sea where you’ve had consistent ice growth over the last few days, whereas the other seas still show decreases, or oscillate between increases and decreases.”

So it seems possible to me that volume never went back up and could possibly have continued declining, as the  thicker ice continued to be melted from underneath.  But  there is no real way of knowing at this point.
Stay tuned!

Link:  http://climateprogress.org/2010/09/18/arctic-sea-ice-melt-aint-over-til-its-over/#comment-296855

6 comments:

  1. Tenney thanks for the links to the UWI water vapor imagery I had not used that before it will be great to show my class tomorrow.

    ReplyDelete
  2. Hey, Tenney - have you seen any research that draws the dot-to-dot picture of the impacts of loss of summer sea ice? I did a poll on my site, and half the folks said that they thought that we'd have an ice free arctic by 2030, but that it would have little impact (ie, costs of food and goods will go up some, but my family will be able to handle it) on their lives.

    I haven't seen anything about the effects of an ice free arctic on Lake Mead and Lake Powell, or about the economic effect of a mass migration of millions of eco-refugees from the US southwest. This seems pretty likely to me in the near (20-30 years) future, but I'm not seeing many folk outside of the scientific community taking it seriously.

    As far as politics, protocols, mitigation and "going green," it looks like we'll have an ice free summer arctic by 2030 no matter what is done; most likely we'll have an ice free arctic by 2020.

    But what does that mean? How is life going to be different? All I'm hearing is that storms are going to be "worse" and that we'll have more heat waves. The response I'm hearing from that is a collective shrug.

    ReplyDelete
  3. Dear MP,

    I have been fascinated by the planetary water vapor streams since I first saw a 7-day animation on the Earth Observatory webpage that describes how Dr. Hansen came to study the global mean temperature using Rossby waves stuff (all over my head). I was particularly stunned because I recognized the events in the animation because I had been going to the Weather Channel site to look at their IR animations of South America (since I live down here). Let me see if I can find that link because it is pretty cool.

    I have it on this blog somewhere.

    In the meantime, please have a look at the selection available from the Univ. of Wisc.

    Oh, and if I write something that is totally out to lunch, please feel free to correct me.

    http://cimss.ssec.wisc.edu/tropic/real-time/mosaic/images/images.html

    ReplyDelete
  4. Loss of Summer Sea Ice -- Impacts

    First, an interesting look through the eyes of the native Inuits is provided in Dr. Heidi Cullen's recent book, "The Weather of the Future."

    If you do not have access to the book, there really is a huge list of impacts, and lots of research on all of them.

    Here on this blog, for example, there are tons of articles on melting permafrost. If you look at a map of northern Siberia, you can see that it was once an enormous flood plain or marsh running up to the edge of the Arctic Sea, which is not all that deep there.

    That land and sea will warm rapidly when there is no ice cover, releasing untold quantities of methane.

    Cullen points out that when there is ice cover, the air is much cold and drier. Further, the warmth in the water below the sea ice is not transferred to the air. We know that the water's temperature is increasing. Take away the ice cover and the energy gets transferred from the water to the air pretty quickly.

    The Inuit say that the ice does not form now like it used to because of clouds. It's one of those positive feedbacks.

    We can also expect the winds passing over this open water that reach Greenland to cause the Greenland Ice Sheet to melt faster because they will be warmer and wetter than if they had passed over sea ice.

    I am not exactly sure, but the changes in the monsoon over the U.S. Southwest may not be as affected by the lack of sea ice in the Arctic as it is by the huge amount of heat pumping out of the Pacific Ocean at the Equator.

    The thing that I think no one really knows is just what exactly the new weather pattern will be over the Arctic once the sea ice is gone and it is quite warm up there. Well, actually, I think the modellers have done the model runs but they just don't want to tell us yet. But let me put it this way (very simply) -- there used to be this cap of cold air that hung around the North Pole, and the hot air from the south has been pushing that cold air out of the Arctic, and just weakening it, and reducing it. Eventually, there won't be a lot of it left. What is that going to do to weather patterns in the Northern Hemisphere? I'd venture to say that they won't be anything like what we have been used to for hundreds of years.

    ReplyDelete
  5. Dear Mauri,

    The University of Wisconsin must be a dreamland for people like me who want to study water vapor streams -- check out this one of the entire planet (and they have animations, too):

    http://www.ssec.wisc.edu/data/comp/wv/LATEST_WV.gif

    Here is a main page for selecting composites:

    http://www.ssec.wisc.edu/data/composites.html

    Enjoy!

    ReplyDelete
  6. Mauri, here is the link to the Earth Observatory article that explains how GISSTemp is derived and which has the WV animation which is a quicktime file
    and take a long time to load up but is soooo worth it:

    http://www.giss.nasa.gov/research/features/200711_temptracker/

    The QuickTime file shows a view of the planet like the one from the EUMETSAT -- so the area on the middle left is mostly Africa.

    http://www.giss.nasa.gov/research/features/200711_temptracker/seviri_water_vapor_720p_best.mov

    The current EUMETSAT animation is at this link:

    http://oiswww.eumetsat.org/IPPS/html/MSG/IMAGERY/WV062/BW/FULLDISC/index.htm

    ReplyDelete