Antarctic iceberg sinks cruise ship
The November 2007 sinking of the cruise ship MS Explorer after it hit an iceberg in Antarctic waters is a reminder that the Antarctic is a dangerous place to sail. Ever since British explorer Ernest Shackleton's ship Endurance met its end when it become trapped and crushed in pack ice near Antarctica, the Antarctic waters have been a notoriously dangerous place for boats. For those of you unfamiliar with the story of Shackleton's ill-fated expedition, I highly recommend a reading of The Endurance: Shackleton's Legendary Antarctic Expedition. The book details the most mind-blowing tale of survival and courage I have ever read. Shackleton's phenomenal leadership skills saved the lives of all of his men. Shackleton refused to sleep for over 30 consecutive days while leading his men in an arduous months-long trek over the treacherous Antarctic sea ice. His voyage to find help using an open boat in winter on the storm-tossed Scotia Sea may rank as the greatest navigation feat of all time.
Figure 1. Antarctic sea ice (purple colors) at the time the MS Explorer hit an iceberg and sank. Summer is approaching in the Southern Hemisphere, leading to melting and break up of the sea ice and plenty of icebergs. Image credit: University of Illinois Cryosphere Today.
Why talk about Antarctic sea ice?
You hear a lot of talk about Arctic sea ice, but not about Antarctic sea ice. That's because Antarctic sea ice is relatively unimportant to the Earth's climate. Antarctica is a huge continent that rises thousands of feet above the ocean. It holds about 90% of the world's fresh water, locked up in its massive ice cap. The presence of such a titanic block of ice at the bottom of the world completely dominates the weather and climate of the region, and the year-to-year fluctuations of sea ice don't have a lot of impact on temperatures there.
The other reason to ignore Antarctic sea ice is that it hasn't changed much over the historical record. A look at the sea ice coverage since 1978 (Figure 2) shows very little change. Climate skeptics have pointed out that Antarctic sea ice has been near its maximum area the past few winters. However, this is not considered statistically significant, and there is no overall trend apparent in the data.
However, Antarctic sea ice may be important because of its ability to insulate and buttress glaciers and semi-permanent ice shelves along the coast. Recent melting of sea ice due to warming temperatures along the Antarctic Peninsula allowed warming ocean waters to penetrate close to shore, triggering the collapse of the Larsen B Ice Shelf in 2002. This Rhode Island-sized chunk of ice had been around thousands of years, and disintegrated in just three days. Any decline of Antarctic sea ice in coming decades might cause a speedier retreat of the continent's glaciers and ice shelves.
Figure 2. Antarctic sea ice area as observed via satellite since 1978. The maximum area in winter has ranged between 14-16 million square kilometers, about the same amount of ocean that the Arctic ice covers in winter. However, the Antarctic sea ice almost entirely melts away in summer, something the Arctic sea ice does not do (yet). Image credit: University of Illinois Cryosphere Today.
Antarctic cooling
What is significant is the fact that most of Antarctica cooled in recent decades (Figure 3). For example, the surface temperature at the South Pole cooled 0.05° C between 1980 and 1999 (Kwok and Comiso, 2002). However, the majority of Antarctica has shown no statistically significant warming over the past 50 years (Turner et al., 2005)--the cooling has just been over the past 25-30 years. In the period 2004-2007, much of the Antarctic warmed (Figure 4). Why did Antarctica cool between 1982 and 2004 if there was global warming going on?
Well, the globe, on average, has warmed about 1.1° F (0.65° C) in the 50 years ending in 2005 (IPCC, 2007). Given that there is a lot of natural variability in the climate, it should be expected that some areas of the globe would not see warming, given the relatively modest magnitude of global warming thus far.
Figure 3. Antarctic surface temperatures as observed via AHVRR satellite measurements between 1982 and 2004. Much of Antarctica cooled during this period. Image credit: IPCC The Physical Science Basis, Figure 3.32.
Figure 4. Antarctic surface temperatures as observed via AHVRR satellite measurements between 1981 and 2007. Note that the cooling trend observed from 1982-2004 has reversed, thanks to warming in the past few years. Image credit: NASA
In addition, the weather of the Antarctic is dominated by a strong band of westerly winds that blow around the pole. This circumpolar vortex extends from the surface to the stratosphere, and can attain very high wind speeds, thanks to the absence of large land masses to slow it down. This vortex tends to isolate Antarctica from the rest of the globe, keeping global warming from influencing Antarctica weather, and allowing the surface to cool. The Antarctic Peninsula, which sticks out from Antarctica towards South America, frequently lies outside the vortex. This has allowed the peninsula to warm significantly, compared to the rest of Antarctica (Figures 3 and 4). The Antarctic circumpolar vortex has strengthened in the past 25-30 years, forming an even stronger barrier than usual. Tree ring records (Jones and Widman, 2004) suggest that the circumpolar vortex has shown similar strengthening in the past, so the current cooling trend in Antarctica may be partly a natural cycle.
Another possibility, favored by climate modelers, is that the strengthening of the circumpolar vortex and recent cooling in Antarctica are primarily due to a combination of the recent increase in greenhouse gases and the opening of the Antarctic ozone hole. The ozone hole opened up at about the same time as the recent cooling began. Ozone absorbs UV radiation which heats the atmosphere around it, so the absence of ozone has led to cooling in the stratosphere over Antarctica. This cooling has been about 10° C in October-November since 1985 (Thompson and Solomon, 2002), and has acted to intensify the circumpolar vortex, leading to surface cooling. If the climate modelers are right, the circumpolar vortex will weaken as the ozone hole diminishes in coming decades. This will allow the Antarctic to begin warming with the rest of the globe.
References and resources
Intergovernmental Panel on Climate Change (IPCC), 2007, The Physical Science Basis.
Jones, J.M., and M. Widman, "Atmospheric science: Early peak in Antarctic oscillation index," Nature 432, 290-291 (18 November 2004) | doi:10.1038/432290b; Published online 17 November 2004.
Kwok, R., and J.C. Comiso, "Spatial patterns of variability in Antarctic surface temperature: Connections to the Southern Hemisphere Annular Mode and the Southern Oscillation", GEOPHYSICAL RESEARCH LETTERS, VOL. 29, NO. 14, 10.1029/2002GL015415, 2002.
Thompson, D.W.J., and S. Solomon, "Interpretation of Recent Southern Hemisphere Climate Change", Science 3 May 2002: Vol. 296. no. 5569, pp. 895 - 899 DOI: 10.1126/science.1069270.
Turner, J. et al., 2005, "Antarctic climate change during the last 50 years", International Journal of Climatology, Volume 25, Issue 3, pp 279-294.
Arctic sea ice
"Antarctic cooling, global warming?" RealClimate.org post, 3 December 2004.
Jeff Masters
Reader Comments
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Severn, England
"You could hear the noise, like a steam train hurtling round the corner. And, around the corner, we were met by a 5-foot solid head of water which was getting bigger and bigger. By the time it got to Garden Cliff, it was at least 9 feet almost double overhead." Steve"Wizard" King
The Severn River in Glouchestershire, England, has become the cradle of this growing sport. Dragged upstream at speeds up to 13 mph, the Severn bore can be a glassy swell, a monstrous breaking wave or even a moving hole as it cruises the English countryside, turning the peaceful river into an inland surf zone. A 1955 account describes one of the first attempts to ride these waves on surfboards, and today the Severn bore is frequently surfed by both board and kayak. The best bore riders can travel several miles, with Steve King's unofficial record being 6.3 miles almost a full hour surfing one continuous wave. The Severn also has the most extensive online documentation at bore riders.com
SIGN ME UP!!!
Riding a tidal bore sounds fun especially the one I posted above because it doesnt get that big just a long ride. Same goes for the tanker wakes in Texas. 2 foot wave the goes for miles.
after looking at that website I wonder why the surfing community hasnt featured it more!!
No nightlife and if the wind's wrong the blackflys will suck you dry, that is of the skeeters don't carry you off first. I bet.
I thought we had skeeters but I didn't know from SKEETERS till I'd been to New Brunswick! Lot to put up with for 2 waves a day. Corse I don't git in no boat got no sides an try to stand up neither. My Daddy didn't raise no fool and my Moma learnt me when to git in outa the rain. The stuff them flatlanders 'll do on a dare would kurl yer hair, I tell you!
Black flys.. screw that. Those things are flying pirannas I tell you. They even bite through neoprene
Shen... that's funny! Would love to go flyfishing! One thing I miss from my childhood is Rainbow Trout! Yummy! Do a bit of fly-fishing in the Bay... just not the same though.
Bone! Happy Early Birthday!
Yea I lived in Florida on the Gulf or as acalled it the Lake Of Mexico. Small but fun waves. But they get great when a storms out there spinning things up.
Shen, love your name!
409. Bonedog 5:13 PM EST on November 29, 2007
after looking at that website I wonder why the surfing community hasnt featured it more!!
No nightlife and if the wind's wrong the blackflys will suck you dry, that is of the skeeters don't carry you off first. I bet.
I thought we had skeeters but I didn't know from SKEETERS till I'd been to New Brunswick! Lot to put up with for 2 waves a day. Corse I don't git in no boat got no sides an try to stand up neither. My Daddy didn't raise no fool and my Moma learnt me when to git in outa the rain. The stuff them flatlanders 'll do on a dare would kurl yer hair, I tell you!
Up here we serve salmon on a cedar plank thats been done on a BBQ, to people...
Down there they serve people on a fiberglass plank, raw to the sharks :)
Thats funny right there, I dont care who you are!
Agreed, thats funny!
Cancun
1 month 5 days 19 hours 12 min 42 sec
Now we just get our ORV sticker and drive to the breaks :) Less chance of fly attacks that way.
Cancun??? Vacation???
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The Barometer Bob Show broadcasts LIVE every Thursday night at 8:00pm/et from Northeast Florida.
The Barometer Bob Show for November 29, 2007!
Bob's Guest will be Henri D. Grissino-Mayer, Associate Professor of Geography, at The University of Tennessee. We will discuss his research on the use of tree rings for paleoclimatology.
You can call into the show LIVE at
1-866-931-8437(U.S.A Toll Free) or 904-259-4229 World Wide (Tolls Apply)
With your host Barometer Bob Brookens from Hurricane Hollow Weather!
Visit StormChat during the Show also. Link
So, where exactly was the earthquake in the Carribean?
Action: | Ignore User
1 decent size shaker and and some little ones
29-NOV-2007 20:11:10 15.09 -61.23 4.8 141.6 LEEWARD ISLANDS
29-NOV-2007 19:34:45 15.10 -61.31 5.0 142.6 LEEWARD ISLANDS
29-NOV-2007 19:00:19 14.92 -61.26 7.3 145.4 WINDWARD ISLANDS
28-NOV-2007 14:18:11 15.05 -60.54 4.8 78.7 LEEWARD ISLANDS
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Thanks...
Up here we serve salmon on a cedar plank thats been done on a BBQ, to people...
Down there they serve people on a fiberglass plank, raw to the sharks :)
Naw, you got it all wrong, They been broiled to a crisp and marinated in Coca Butter. It's a wonder the Sharks don't spit em back out.
But that salmon now that's some good victuals. If I live and keep my health I'm gonna have a go at hooking on to one of those
I set the limit auf 5.0 world wide and I've gotten one mail so far, so no problem and I think that 1 GB is quite hard to fill up quickly. :) I'll be off now, good night everyone and see you later today for the last day of the Atlantic hurricane season 2007.
2007 ATLANTIC HURRICANE SEASON
Congrats Jeff on making the big newspaper:
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The season flew by so fast.
Happy Holidays to everyone!
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
920 PM PST THU NOV 29 2007
LONG TERM...THE LATEST GFS IS SIMILAR TO PREVIOUS RUNS AND
CONSIDERING THE DRAMATIC PATTERN CHANGE OF UNDERCUTTING THE BIG
RIDGE I AM SURPRISED HOW CONSISTENT THE MODELS HAVE BEEN. BY SUNDAY
EVENING THERE IS DEEP LOW PRESSURE OUT AROUND 40N/140W AND SOMETHING
AROUND A 960MB LOW WILL TRACK TO THE CHARLOTTES MONDAY. MORE DETAILS
REVEALED IN THE ISSALLOBARS...BUT AT THIS LEAD TIME SUFFICE TO SAY
WINDY AND WARM. STRONG SLY FLOW ALOFT WILL TAKE A GOOD 24 HOURS TO
WORK THRU WRN WA SUNDAY NIGHT AND MONDAY. WINDS AT H850 OVER THE
INTERIOR OF WRN WA PROBABLY WILL AROUND 75KT FROM 06Z MON TO 00Z TUE
(PERHAPS HIGHER BASED ON SOME OF THE NAM SIMULATIONS) AND WINDS
ALONG THE COAST ARE IN EXCESS OF 100KTS SUNDAY NIGHT AND MONDAY
(110KTS IN THE NAM). WOW. A TYPICAL STRONG FRONTAL SYSTEM HAS A 50
OR 60KT PLUME AT H850. 24 HOUR RAINFALL AMOUNTS OFF OF THE 12Z MM5
EXTENSION HAD SOMETHING ON THE ORDER OF 5-10 INCHES FOR THE OLYMPICS
(WHICH DOES NOT SEEM AS HIGH AS IT COULD BE W/ 100KT FLOW OVER THE
RIDGES) AND PRECIP OF 1.5 TO 3 INCHES CASCADES. THE HYDROLOGY OF THE
EVENT WILL BE COMPLICATED IN THE CASCADES BY MOSTLY SNOW HAVING
FALLEN IN THE MOUNTAINS ON SUNDAY FOLLOWED BY SOUTHERLY FLOW WHICH
ISN`T PARTICULARLY WET FOR THE CASCADES. MM
WOW is right LOL
oh and this
MARINE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SEATTLE WA
440 PM PST THU NOV 29 2007
PZZ150-153-156-170-173-176-010000-
/X.NEW.KSEW.MA.S.0003.071130T0040Z-071201T0000Z/
COASTAL WATERS FROM CAPE FLATTERY TO JAMES ISLAND OUT 20 NM-
COASTAL WATERS FROM JAMES ISLAND TO POINT GRENVILLE OUT 20 NM-
COASTAL WATERS FROM POINT GRENVILLE TO CAPE SHOALWATER OUT 20 NM-
COASTAL WATERS FROM CAPE FLATTERY TO JAMES ISLAND 20 TO 60 NM-
WATERS FROM JAMES ISLAND TO POINT GRENVILLE 20 TO 60 NM-
COASTAL WATERS FROM POINT GRENVILLE TO CAPE SHOALWATER 20 TO
60 NM-
440 PM PST THU NOV 29 2007
...HURRICANE FORCE WINDS ARE POSSIBLE ACROSS THE WASHINGTON COASTAL
WATERS EARLY NEXT WEEK...
A POWERFUL CYCLONE WILL DEVELOP OVER THE EASTERN PACIFIC THIS
WEEKEND AND THEN RAPIDLY DEEPEN TO 945 MB SUNDAY NIGHT AS IT
RACES TOWARD BRITISH COLUMBIA. WINDS WILL RISE TO STORM FORCE
SOUTHERLY BEHIND THE STRONG WARM FRONT SUNDAY NIGHT AND PERSIST
INTO MONDAY BEFORE GRADUALLY EASING. THERE IS THE POTENTIAL FOR
GUSTS TO REACH 70 KNOTS OVER THE AREA DURING THIS PERIOD.
IN ADDITION TO THE WIND...SEAS ARE EXPECTED TO BUILD TO AS HIGH
AS 36 FEET ON MONDAY. DUE TO THE CHAOTIC NATURE OF THE SEAS IT
WILL BE DIFFICULT TO DISTINGUISH THE SWELL AND WIND WAVE
COMPONENTS UNTIL AFTER THE COLD FRONT PASSES AND WINDS EASE
WOW 36 foot sea
any one that lives in SEATTLE needs to start geting thing that they need for this storm and get redy for HURRICANE FORCE WINDS POSSIBLE move loss thing in doors
this storm is going to be a big one
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