Any speculation on the giant polynya in the Beaufort Sea?

[Sinimod]

http://www.baltimoresun.com/news/health/bal-hs.ice22sep22,0,4648388.story

A hole (polynya) the size of Indiana has opened in the Beaufort Sea, a part of the Arctic Ocean. Can anyone speculate on the the cause of this hole, the likes of which have not been witnessed before in this part of the Arctic?

 

[Sinimod]

Polynyas

Sorry, a polynya is an opening in the ice covering the sea.

http://nsidc.org/seaice/characteristics/polynyas.html

This particular polynya in the Beaufort Sea is exceptionally large.

 

[Mk]

This happens every year all the time doesn't it?

 

[Andre]

Well you got to look all things simulaneously.

http://www.sciencedaily.com/releases/2006/09/060921123321.htm

Short-Term Ocean Cooling Suggests Global Warming 'Speed Bump'
The average temperature of the water near the top of the Earth's oceans has significantly cooled since 2003. New research suggests global warming trends are not always steady in their effects on ocean temperatures.

One of the things that Richard Lindzen teaches is N-S heat distribution by ocean currents and atmosphere, levelling out temperature differences between arctic and tropics. So these two combined may suggest an increased interchange of heat. But of course, everything is global warming, so such a logical explanation is out of the question.

 

[Sinimod]

This happens every year all the time doesn't it?

True, polynyas are a natural and necessary part of sea ice dynamics. However, in terms of human observation, the size of this polynya is unprecedented.

 

[Sinimod]

Well you got to look all things simulaneously.

http://www.sciencedaily.com/releases/2006/09/060921123321.htm



One of the things that Richard Lindzen teaches is N-S heat distribution by ocean currents and atmosphere, levelling out temperature differences between arctic and tropics. So these two combined may suggest an increased interchange of heat. But of course, everything is global warming, so such a logical explanation is out of the question.

It's interesting, is it not, that this exceptionally large polynya has formed during an ocean cooling event.

If Arctic Ocean waters are warming, as NASA has claimed (http://www.nasa.gov/centers/goddard/earthandsun/arctic_changes.html) , would that not slow the heat exchange between the tropics and the poles, with the attendant weakening of atmospheric circulation, alteration of storm tracks, and alteration of temperature and pressure patterns, as suggested in the article I just referenced by NASA?

Also, I would like to have a better understanding of the apparent synchronicity of increased ice melting at the poles, and shallow ocean water cooling. Is it possible there could be some linkage? Maybe you could enlighten me.

 

[Andre]

If Arctic Ocean waters are warming, as NASA has claimed (http://www.nasa.gov/centers/goddard/earthandsun/arctic_changes.html) , would that not slow the heat exchange between the tropics and the poles, with the attendant weakening of atmospheric circulation, alteration of storm tracks, and alteration of temperature and pressure patterns, as suggested in the article I just referenced by NASA?

We may be looking at a cyclic event here. For some odd reason in the chaos of ocean currents, there could be an increase in (subsurface?) flows towards the poles, upwelling somewhere to form polynyas, then there would also be a compensating flow back to the tropics, cooling it and perhaps suppressing hurricanes to form. Just thinking out loud.

Then in a second stadium, the tropics pole temperature gradient having decreased, those flows may reduce again, resulting indeed in cooling poles and heating tropics again, closing the cycle.

Coming to think of that, testing that idea, the clear temperature spike of the Arctic around 1940 AD about the same as today, may have caused a clear reduction in tropical storms. We should be able to find that out

(link did not work properly though)

 

[Skyhunter]

Coming to think of that, testing that idea, the clear temperature spike of the Arctic around 1940 AD about the same as today, may have caused a clear reduction in tropical storms. We should be able to find that out

A quick google brought me this;

http://www.physorg.com/news6793.html

"Even though hurricane activity as definitely increased over the past decade, the period 1996 through 2005 to this moment has not produced as many major landfalling U.S. hurricanes (6; perhaps 7 with Rita) as the period 1941 to 1950, when 10 such storms hit the nation.

Clearly not a reduction.

 

[reasonmclucus]

Is there any indication of undersea geothermal activity in the region? A few years ago an undersea volcano was discovered in the area of Antarctica in which the Larson B ice shelf collapsed.

http://www.sciencedaily.com/releases/2004/05/040527235943.htm

 

[Andre]

A quick google brought me this;

http://www.physorg.com/news6793.html

Clearly not a reduction.

Have you counted this years Hurricanes? and weren't we talking about polynya of today? Not 2005.

Is there any indication of undersea geothermal activity in the region? A few years ago an undersea volcano was discovered in the area of Antarctica in which the Larson B ice shelf collapsed

Interesting thought, althought the influence of oceanism volcanism may be overestimated considering the immense volumes of water and the huge amount of heat required.

 

[Sinimod]

Is there any indication of undersea geothermal activity in the region? A few years ago an undersea volcano was discovered in the area of Antarctica in which the Larson B ice shelf collapsed.

http://www.sciencedaily.com/releases/2004/05/040527235943.htm

Undersea volcanic activity in the Arctic Ocean occurs along the Gakkel Ridge, the slowest spreading mid-ocean ridge currently known. However, this is not close to the Beaufort Sea.

http://www.geolsoc.org.uk/template.cfm?name=Gakkel2

 

[Skyhunter]

Have you counted this years Hurricanes? and weren't we talking about polynya of today? Not 2005.

You suggested that there may have been reduced hurricane activity around 1940, I simply checked and found that it was not the case. The period 1941-1950 holds the record for the most major storms making landfall.

Records are not as comprehensive before 1940, but here is a record of Atlantic hurricanes since then.

Scientists know hurricane seasons go through cycles lasting decades producing few hurricanes, then switching to periods of more intense activity. From 1940 through 1969, there were 182 hurricanes, with 88 of them growing into Category 3, 4 or 5: the major storms that cause the worst damage.

From 1970 to '94, there were 123 hurricanes and only 38 major storms.

The nine years from 1995 through 2003 saw 69 hurricanes, with 32 reaching Category 3 and higher, only six fewer than the previous 25 seasons.

182 / 30 = 6.07 hurricanes per year

123 / 25 = 4.92 hurricanes per year

69 / 9 = 7.66 hurricanes per year

add 2004 and 2005 9 and 14

92 / 11 = 8.36

We seem to definitely be in an increased Atlantic hurricane cycle. Note that the category 3 and higher have dramatically increased.

Since the 2006 season is not complete, I don't see any reason to include it.

 

[Mk]

http://img54.imageshack.us/img54/936/snapshot20060927164335ie4.png
Data from NOAA.

 

[Skyhunter]

http://www.baltimoresun.com/news/health/bal-hs.ice22sep22,0,4648388.story

A hole (polynya) the size of Indiana has opened in the Beaufort Sea, a part of the Arctic Ocean. Can anyone speculate on the the cause of this hole, the likes of which have not been witnessed before in this part of the Arctic?

The oceans have warmed during the past 20 years. the ice is thinner and therefore more susceptible to warm upwelling. Once the ice is gone the suns radiation would be absorbed by the water, further warming the polynya and causing it to grow.

As the Earth warms, especially in the Arctic, we should expect to see more of this.

 

[Skyhunter]

http://img54.imageshack.us/img54/936/snapshot20060927164335ie4.png
Data from NOAA.

That must be an old graph, 2004 had 9 hurricanes in the Atlantic. Gaston was not originally categorized as a hurricane, but was subsequently upgraded.

http://daac.gsfc.nasa.gov/hurricane/HurricaneGaston2004.shtml

Gaston, originally designated a tropical storm at landfall, was upgraded to a weak Category 1 Hurricane in post-storm analysis when it was discovered that Doppler Radar velocity data revealed Gaston had 65 kt (75 mph) surface winds.

http://www.ncdc.noaa.gov/oa/climate/research/2004/hurricanes04.html

The Atlantic Basin had a more active season than average in 2004 with 15 tropical storms and 9 hurricanes, including 6 major hurricanes. The average (based on data from 1944-1996) is approximately 10 named storms and 6 hurricanes, including 2-3 major hurricanes.

Here is a more recent graph

http://www.ncdc.noaa.gov/img/climate/research/2005/ann/namedstorms-majorhurr.gif

 

[twisting_edge]

There's one big problem (as has already been mentioned) with older data: it's incompleteness. That's why the NOAA also has a table of only landfalling US hurricanes here:

http://www.nhc.noaa.gov/pastdec.shtml"

If you graph that (and adjust the period 2001-2004 by a factor of 10/4), it looks like this:

http://www.verdomde.net/xfr/HURR.gif"

It's actually not fair, because the NOAA estimates SE Florida records (even for landfalling hurricanes) are complete only after 1900 (the area was very thinly populated). Note that 2005 was very active, but 2006 (admittedly not done yet) is right on average so far this season (and therefore very inactive for the 2001-2004 data group). If you include both, the graph looks about the same.

There's something callled the "Atlantic Multi-decadal Oscillation" that reinsurers have been worrying about for two decades now. The NOAA has a few FAQs on it. Current variations in hurricane frequency fall well within the potential limits of the AMDO. You don't need global warming at all to explain the current increase. Occam's Razor applies.

 

[twisting_edge]

Here's the NOAA FAQ on the AMO, BTW (gee, do you think I could get any more acronyms in that?):

http://www.aoml.noaa.gov/phod/amo_faq.php"

There's other pages on NOAA that say the AMO is the sole driver, and some that say global warming is a contributing factor. That FAQ seems about the middle of the road.

 

[Evo]

Here's the NOAA FAQ on the AMO, BTW (gee, do you think I could get any more acronyms in that?):

http://www.aoml.noaa.gov/phod/amo_faq.php"

There's other pages on NOAA that say the AMO is the sole driver, and some that say global warming is a contributing factor. That FAQ seems about the middle of the road.

That's very interesting, thanks for the link!