Arctic sea ice at a record low again; a warmer February for the U.S. coming
Arctic sea ice extent for January 2011 was the lowest on record for the month, and marked the second consecutive month a record low has been set, according to the National Snow and Ice Data Center. Most of the missing ice was concentrated along the shores of Northeast Canada and Western Greenland. Relative to the 1979 - 2000 average, the missing ice area was about twice the size of Texas, or about 60% of the size of the Mediterranean Sea. Hudson Bay in Canada did not freeze over until mid-January, the latest freeze-up date on record, and at least a month later than average. The late freeze-up contributed to record warm winter temperatures across much of the Canadian Arctic in December and January. Bob Henson of the National Center for Atmospheric Research has a very interesting post on this, noting that Coral Harbor on the shores of Hudson Bay had a low temperature on January 6 that was 30°C (54°F) above average--a pretty ridiculous temperature anomaly. He quotes David Phillips, a senior climatologist with Environment Canada, who discussed the lack of ice near Canada's Baffin Island: "The Meteorological Service of Canada was still writing marine forecasts as of 7 January, well beyond anything we have ever done." Henson also writes:
"The extremes have been just as impressive when you look high in the atmosphere above these areas. Typically the midpoint of the atmosphere's mass--the 500-millibar (500 hPa) level--rests around 5 kilometers (3 miles) above sea level during the Arctic midwinter. In mid-December, a vast bubble of high pressure formed in the vicinity of Greenland. At the center of this high, the 500-mb surface rose to more than 5.8 kilometers, a sign of remarkably mild air below. Stu Ostro (The Weather Channel) found that this was the most extreme 500-mb anomaly anywhere on the planet in weather analyses dating back to 1948.
Farther west, a separate monster high developed over Alaska in January. According to Richard Thoman (National Weather Service, Fairbanks), the 500-mb height over both Nome and Kotzebue rose to 582 decameters (5.82 km). That's not only a January record: those are the highest values ever observed at those points outside of June, July, and August."
Figure 1. Monthly January sea ice extent for 1979 to 2011 shows a decline of 3.3% per decade. Image credit: National Snow and Ice Data Center.
The warm temperatures in Canada and record sea ice loss in the Arctic were also due, in part, to a strong negative phase of the Arctic Oscillation (AO). The Arctic Oscillation and its close cousin, the North Atlantic Oscillation (NAO) are naturally occurring pressure patterns in the Arctic and mid-latitudes. A negative AO and NAO results when we have weaker than normal low pressure over the Arctic, and weaker than normal high pressure over the Azores Islands. This fosters an easterly flow of air off the warm Atlantic Ocean into the Canadian Arctic, and also weakens the winds of the polar vortex, the ring of counter-clockwise spinning winds that encircles the Arctic. A weaker polar vortex allows cold air to spill southwards out of the Arctic into eastern North America and Western Europe. Thus, the strongly negative AO and NAO the past two winters have been largely responsible for the cold and snowy winters in these regions, and exceptionally warm conditions in the Arctic. I described this pattern in more detail in my December post titled, Florida shivers; Hot Arctic-Cold Continents pattern is back. It is possible that Arctic sea ice loss is largely responsible for the unusual Arctic Oscillation pattern we've observed during the past two winters, as well as for the record-strength ridges of high pressure observed over Greenland and Alaska this winter. It should not surprise us that Arctic sea ice loss would be capable of causing major perturbations to Earth's weather, since it is well known that changes from average in sea surface temperatures over large regions of the ocean modify the jet stream, storm tracks, and precipitation patterns. The El Niño and La Niña patterns are prime examples of this (though the area of oceans affected by these phenomena are much larger than what we're talking about in the Arctic.) Another example: Feudale and Shukla (2010) found that during the summer of 2003, exceptionally high sea surface temperatures of 4°C (7°F) above average over the Mediterranean Sea, combined with unusually warm SSTs in the northern portion of the North Atlantic Ocean near the Arctic, combined to shift the jet stream to the north over Western Europe and create the heat wave of 2003, the deadliest heat wave in history with 30,000 - 50,000 deaths in Europe.
References
Feudale, L., and J. Shukla (2010), "Influence of sea surface temperature on the European heat wave of 2003 summer. Part I: an observational study", Climate Dynamics DOI: 10.1007/s00382-010-0788-0
Figure 2. The 6-10 temperature forecast issued by NOAA's Climate Prediction Center calls for an above-average chance of warm temperatures across most of the U.S. by mid-February.
A warmer forecast for February
Over the past two weeks, the Arctic Oscillation has undergone a major transition, changing from negative to positive. This means that low pressure over the Arctic has intensified, which will act to speed up the counter-clockwise spinning winds (the polar vortex.) This spin-up of the polar vortex will tend to keep cold air bottled up the Arctic, leading to more Arctic sea ice formation and warmer winter conditions over the U.S. This warm-up is reflected in the latest 6 - 10 day temperature outlook from NOAA's Climate Prediction Center (Figure 2.) Could it be the groundhog was right, and we have only three more weeks of winter left? Time will tell--we have little skill predicting what may happen to the Arctic Oscillation more than about two weeks in advance.
Jeff Masters
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You guys know your civil rights, right?
If the republican governor of Puerto Rico signs a law that makes illegal protests and any type of marches or manifestations by civilians that interrupt any public services related to health or education, is that legal?
Doesn't that go against the right to freedom of speech and association?
It's not just climatologists; it's nearly every national and international scientific body. Here's a listing of such bodies that have come out with position statements supporting AGWT: the InterAcademy Council, the European Academy of Sciences and Arts, the International Council of Academies of Engineering and Technological Sciences, the Network of African Science Academies, the Royal Society of New Zealand, the Royal Society of the United Kingdom, the Polish Academy of Sciences, the National Research Council, the American Association for the Advancement of Science, the American Chemical Society, the American Institute of Physics, the American Physical Society, the Australian Institute of Physics, the European Physical Society, the European Science Foundation, the Federation of Australian Scientific and Technological Societies, the American Geophysical Union, the European Federation of Geologists, the European Geosciences Union, the Geological Society of America, the Geological Society of Australia, the Geological Society of London, the International Union of Geodesy and Geophysics, the National Association of Geoscience Teachers, the American Meteorological Society, the Australian Meteorological and Oceanographic Society, the Canadian Foundation for Climate and Atmospheric Sciences, the Canadian Meteorological and Oceanographic Society, the Royal Meteorological Society, the World Meteorological Organization, the American Quaternary Association, the International Union for Quaternary Research, the American Association of Wildlife Veterinarians, the American Institute of Biological Sciences, the American Society for Microbiology, the Australian Coral Reef Society, the UK Institute of Biology, the Society of American Foresters, the Wildlife Society, the American Academy of Pediatrics, the American College of Preventive Medicine, the American Medical Association, the American Public Health Association, the Australian Medical Association, the World Federation of Public Health Associations, the World Health Organization, the American Astronomical Society, the American Statistical Association, the the Institution of Engineers Australia, the International Association for Great Lakes Research, the Institute of Professional Engineers New Zealand, along with national science academies for the following nations/areas: Australia, Belgium, Brazil, Cameroon, Canada, the Caribbean, China, France, Ghana, Germany, Indonesia, Ireland, Italy, India, Japan, Kenya, Madagascar, Malaysia, Mexico, Nigeria, New Zealand, Russia, Senegal, South Africa, Sudan, Sweden, Tanzania, Turkey, Uganda, the United Kingdom, the United States, Zambia, and Zimbabwe.
(While there are a small handful of organizations that remain officially non-commital, none reject the theory of AGWT. For the record, the last one that did was the American Association of Petroleum Geologists--go figure--but even that group went non-commital a few years ago.)
(And, no, I'm not in any way saying that there are climatologists in those groups. Nor am I saying that every person in those groups, climatologist or otherwise, adheres to AGWT. But the groups as a whole have taken the majority opinion, and based their position statements on that opinion.)
Is it really anyone's opinion that the tens of thousands of scientists represented by these groups are all involved in a conspiracy to deprive people of their freedoms or to extract exorbitant taxes? And does anyone really believe that a handful of politicians bought and paid for by Big Energy carry the same science credibility as the majority of those in the above bodies do?
Have you had a chance to consider the implications of these two new papers below? How might they change current climate change models and interpretation of global warming trends?
Thank you.
1. Bathymetric controls on Pliocene North Atlantic and Arctic sea surface temperature and deepwater production.
M.M. Robinson, P.J. Valdes, A.M. Haywood Et Alia.
Palaeogeog., Palaeoclim., Palaeoecol., In Press, Online 1/15/2011.
doi:10.1016/j.palaeo.2011.01.004
http://www.sciencedirect.com/science?_ob=ArticleU RL&_udi=B6V6R-51YBTRC-1&_user=10&_coverDate=01%2F1 5%2F2011&_rdoc=1&_fmt=high&_orig=search&_origin=se arch&_sort=d&_docanchor=&view=c&_acct=C000050221&_ version=1&_urlVersion=0&_userid=10&md5=31d81caa9b7 8fcb5938ee9d81625ca4c&searchtype=a
Abstract
The mid-Pliocene warm period (MPWP; ~ 3.3 to 3.0 Ma) is the most recent interval in Earth's history in which global temperatures reached and remained at levels similar to those projected for the near future. The distribution of global warmth, however, was different than today in that the high latitudes warmed more than the tropics. Multiple temperature proxies indicate significant sea surface warming in the North Atlantic and Arctic Oceans during the MPWP, but predictions from a fully coupled ocean–atmosphere model (HadCM3) have so far been unable to fully predict the large scale of sea surface warming in the high latitudes. If climate proxies accurately represent Pliocene conditions, and if no weakness exists in the physics of the model, then model boundary conditions may be in error. Here we alter a single boundary condition (bathymetry) to examine if Pliocene high latitude warming was aided by an increase in poleward heat transport due to changes in the subsidence of North Atlantic Ocean ridges. We find an increase in both Arctic sea surface temperature and deepwater production in model experiments that incorporate a deepened Greenland–Scotland Ridge. These results offer both a mechanism for the warming in the North Atlantic and Arctic Oceans indicated by numerous proxies and an explanation for the apparent disparity between proxy data and model simulations of Pliocene northern North Atlantic and Arctic Ocean conditions. Determining the causes of Pliocene warmth remains critical to fully understanding comparisons of the Pliocene warm period to possible future climate change scenarios.
Research Highlights
► We alter GCM bathymetry to see if warming is aided by ocean ridge subsidence. ► We find an increase in both Arctic sea surface temperature and deepwater production. ► The results offer a warming mechanism and an explanation for data-model disparity. ► Our results are compatible with paleoceoanographic and geophysical evidence. ► The Iceland–Faroe Ridge has a greater effect on climate than does Denmark Strait.
2. Weakening of the equatorial Atlantic cold tongue over the past six decades.
Hiroki Tokinaga1 & Shang-Ping Xie1.
Nature Geoscience 2011
doi:10.1038/ngeo1078
http://www.nature.com/ngeo/journal/vaop/ncurrent/ full/ngeo1078.html
Seasonal and interannual variations of the equatorial cold tongue are defining features of the tropical Atlantic Ocean, with significant climatic and biogeochemical effects. However, its long-term changes are poorly understood owing to biases in observations and climate models. Here we use a suite of bias-corrected observations, and find that cold-tongue variability has weakened during the past six decades. We find that sea surface temperature has increased across the basin, with a local enhancement over the eastern equatorial Atlantic. This warming pattern of the sea surface is most pronounced during boreal summer, reducing the annual cycle through a positive ocean–atmosphere feedback. Specifically, the eastward-intensified warming leads to enhanced atmospheric convection in the equatorial eastern Atlantic region, as well as to less vigorous trade winds. These in turn deepen the thermocline in the east, and reinforce the sea surface warming pattern. The flattened thermocline and reduced thermocline feedback weaken interannual variability of equatorial sea surface temperatures and Guinea coast precipitation associated with the Atlantic Niño. We suggest that the observed changes could be associated with cooling by anthropogenic aerosols, an effect that is stronger in the Northern than in the Southern Hemisphere. If the aerosol emissions decrease in the next decades, the tropical Atlantic may experience yet another shift as the greenhouse gas forcing increases.
new ENtry by Dr. Masters.
Any graphs to back that up. I don't really see AO going neg. this month.
http://www.cpc.ncep.noaa.gov/products/precip/CWli nk/daily_ao_index/ao_index_mrf.shtml
1.I hate spring,and....
2.My alergies are terrible.
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