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Politics : The Environmentalist Thread -- Ignore unavailable to you. Want to Upgrade?

To: Bread Upon The Water who wrote (25155)	9/6/2009 1:17:33 PM
From: alanrs	Read Replies (1) \| Respond to of 36918

As someone with no formal training in the subject, nor any experience with computer models, I saw 2 potential problems with the article. "Greenhouse gases are the most likely cause of the recent rise in Arctic temperatures, said McKay and his co-author Jonathan T. Overpeck, a UA professor of geosciences and director of UA's Institute of the Environment." This is an assertion I have no way of checking. For instance, I don't know about the large ocean currents, another possible factor in temperature change at a specific location. And then there is the problem of not knowing what I don't know, so I am unclear about what direction to look to further educate myself to either verify or refute this assertion. "The analysis shows that summer temperatures in the Arctic, in step with reduced energy from the sun, cooled at an average rate of about 0.36 degrees F (0.2 degrees C) per thousand years -- until the 20th century." There is an order of magnitude problem here. If the granularity exists for him to say the cooling was at an average rate of 0.036 degrees F (0.02 degrees C) per HUNDRED years--until the 20th century, he should have said that. If it doesn't, then that sentence is just blather. There may be other problems with the article, I don't know, those two just stuck out. Which is not to say anything about him being right or wrong. He may be right, he just doesn't prove it here IMO. ARS

To: Bread Upon The Water who wrote (25155)	9/6/2009 1:59:10 PM
From: longnshort	Read Replies (1) \| Respond to of 36918

didn't they find a volcano on the arctic floor ?

To: Bread Upon The Water who wrote (25155)	9/6/2009 2:01:20 PM
From: longnshort	Read Replies (1) \| Respond to of 36918

Cold water ocean circulation doesn't work as expected (oops throw those computer models out) DURHAM, N.C. -- The familiar model of Atlantic ocean currents that shows a discrete "conveyor belt" of deep, cold water flowing southward from the Labrador Sea is probably all wet. New research led by Duke University and the Woods Hole Oceanographic Institution relied on an armada of sophisticated floats to show that much of this water, originating in the sea between Newfoundland and Greenland, is diverted generally eastward by the time it flows as far south as Massachusetts. From there it disburses to the depths in complex ways that are difficult to follow. A 50-year-old model of ocean currents had shown this southbound subsurface flow of cold water forming a continuous loop with the familiar northbound flow of warm water on the surface, called the Gulf Stream. "Everybody always thought this deep flow operated like a conveyor belt, but what we are saying is that concept doesn't hold anymore," said Duke oceanographer Susan Lozier. "So it's going to be more difficult to measure these climate change signals in the deep ocean." And since cold Labrador seawater is thought to influence and perhaps moderate human-caused climate change, this finding may affect the work of global warming forecasters. "To learn more about how the cold deep waters spread, we will need to make more measurements in the deep ocean interior, not just close to the coast where we previously thought the cold water was confined," said Woods Hole's Amy Bower. Lozier, a professor of physical oceanography at Duke's Nicholas School of the Environment and Bower, a senior scientist in the department of physical oceanography at the Woods Hole Institution, are co-principal authors of a report on the findings to be published in the May 14 issue of the research journal Nature. Their research was supported by the National Science Foundation. Climatologists pay attention to the Labrador Sea because it is one of the starting points of a global circulation pattern that transports cold northern water south to make the tropics a little cooler and then returns warm water at the surface, via the Gulf Stream, to moderate temperatures of northern Europe. Since forecasters say effects of global warming are magnified at higher latitudes, that makes the Labrador Sea an added focus of attention. Surface waters there absorb heat-trapping carbon dioxide from the atmosphere. And a substantial amount of that CO2 then gets pulled underwater where it is no longer available to warm Earth's climate. "We know that a good fraction of the human caused carbon dioxide released since the Industrial revolution is now in the deep North Atlantic" Lozier said. And going along for the ride are also climate-caused water temperature variations originating in the same Labrador Sea location. The question is how do these climate change signals get spread further south? Oceanographers long thought all this Labrador seawater moved south along what is called the Deep Western Boundary Current (DWBC), which hugs the eastern North American continental shelf all the way to near Florida and then continues further south. But studies in the 1990s using submersible floats that followed underwater currents "showed little evidence of southbound export of Labrador sea water within the Deep Western Boundary Current (DWBC)," said the new Nature report. Scientists challenged those earlier studies, however, in part because the floats had to return to the surface to report their positions and observations to satellite receivers. That meant the floats' data could have been "biased by upper ocean currents when they periodically ascended," the report added. To address those criticisms, Lozier and Bower launched 76 special Range and Fixing of Sound floats into the current south of the Labrador Sea between 2003 and 2006. Those "RAFOS" floats could stay submerged at 700 or 1,500 meters depth and still communicate their data for a range of about 1,000 kilometers using a network of special low frequency and amplitude seismic signals. But only 8 percent of the RAFOS floats' followed the conveyor belt of the Deep Western Boundary Current, according to the Nature report. About 75 percent of them "escaped" that coast-hugging deep underwater pathway and instead drifted into the open ocean by the time they rounded the southern tail of the Grand Banks. Eight percent "is a remarkably low number in light of the expectation that the DWBC is the dominant pathway for Labrador Sea Water," the researchers wrote. Studies led by Lozier and other researchers had previously suggested cold northern waters might follow such "interior pathways" rather than the conveyor belt in route to subtropical regions of the North Atlantic. But "these float tracks offer the first evidence of the dominance of this pathway compared to the DWBC." Since the RAFOS float paths could only be tracked for two years, Lozier, her graduate student Stefan Gary, and German oceanographer Claus Boning also used a modeling program to simulate the launch and dispersal of more than 7,000 virtual "efloats" from the same starting point. "That way we could send out many more floats than we can in real life, for a longer period of time," Lozier said. Subjecting those efloats to the same underwater dynamics as the real ones, the researchers then traced where they moved. "The spread of the model and the RAFOS float trajectories after two years is very similar," they reported. "The new float observations and simulated float trajectories provide evidence that the southward interior pathway is more important for the transport of Labrador Sea Water through the subtropics than the DWBC, contrary to previous thinking," their report concluded. "That means it is going to be more difficult to measure climate signals in the deep ocean," Lozier said. "We thought we could just measure them in the Deep Western Boundary Current, but we really can't." eurekalert.org

To: Bread Upon The Water who wrote (25155)	9/6/2009 4:17:29 PM
From: Alastair McIntosh	Read Replies (1) \| Respond to of 36918

Arctic Temperature Reporting In The News Needs A Reality Check There new articles that claim the Arctic is rapidly warming. These articles are an excellent examples of the cherrypicking of particular published papers to promote the very narrow perspective of the journalists. These include An Associated Press news article by Randolph E. Schmid titled “Arctic reverses long-term trend”. A New York Times article by Andrew C. Revkin titled “Humans May Have Ended Long Arctic Chill”. The Schmid article has the text “The most recent 10-year interval, 1999-2008, was the warmest of the last 2,000 years in the Arctic, according to the researchers led by Darrell S. Kaufman, a professor of geology and environmental science at Northern Arizona University. Summer temperatures in the Arctic averaged 2.5 degrees Fahrenheit (1.4 degrees Celsius) warmer than would have been expected if the cooling had continued, the researchers said. The finding adds fuel to the debate over a House-passed climate bill now pending in the Senate. The administration-backed measure would impose the first limits on greenhouse gases and eventually would lead to an 80 percent reduction by putting a price on each ton of climate-altering pollution.” Revkin reinforces this extreme view in his September 3 2009 article with his figure of 2000 years of Arctic surface temperatures, with each decade having the same temporal resolution as the last 10 years. The publication of these news articles are clearly meant to influence the political process, as evident in the last paragraph, where Schmid writes “The finding adds fuel to the debate over a House-passed climate bill now pending in the Senate.” The documentation of their biased reporting is easy to show. For example, they do not report on observational data which does not show this rapid recent warming; e.g. see that the current high latitude temperatures are close to the longer term average since 1958 The Danish Meteorological Institute Daily Mean Temperatures in the Arctic 1958 – 2008 [and thanks to the excellent weblog Watts Up With That for making this easily available to us!] There are also peer reviewed papers which show that the Schmid and Revkin articles are biased; e. g. see i) the areal coverage of the coldest middle tropospheric temperatures (below -40C) have not changed radically as shown in the Revkin figure; see Herman, B., M. Barlage, T.N. Chase, and R.A. Pielke Sr., 2008: Update on a proposed mechanism for the regulation of minimum mid-tropospheric and surface temperatures in the Arctic and Antarctic. J. Geophys. Res.-Atmos., 113, D24101, doi:10.1029/2008JD009799. and ii) there is a warm bias in the Arctic surface temperature measurements when they are used to characterize deeper atmospheric warming; see Klotzbach, P.J., R.A. Pielke Sr., R.A. Pielke Jr., J.R. Christy, and R.T. McNider, 2009: An alternative explanation for differential temperature trends at the surface and in the lower troposphere. J. Geophys. Res., accepted. At least the news Editors of the newspapers are starting to recognize that these journalists are presenting slanted news. The Schmid article appeared only on page 12 of my local newspaper. pielkeclimatesci.wordpress.com Click on the above to see the links in the article. IN particular you should look at: ocean.dmi.dk The link show arctic temperatures back to 1958 and there appears to be no significant change in arctic summer temps since then.