Sounds like you believe in global warming Harry.
REH From: [email protected] [mailto:[email protected]] On Behalf Of Harry Pollard Sent: Saturday, April 09, 2011 8:32 PM To: 'RE-DESIGNING WORK, INCOME DISTRIBUTION, EDUCATION' Subject: Re: [Futurework] BBC News - New York set to be big loser as sea levels rise New York set to be big loser as sea levels rise "Ice sheets: These vast reserves contain billions of tonnes of frozen water - if the largest of them (the East Antarctic Ice Sheet) melts, the global sea level will rise by an estimated 64m." My golly, things look bad! Let's have a look at research results, culled from CO2 Science. Here we go. (Melt) Alley et al. (2005), claimed that "the Greenland Ice Sheet may melt entirely from future global warming," (NoMelt) Yet, just one day earlier, Johannessen et al. (2005), working with satellite-altimeter data from Greenland, reported in a Sciencexpress paper posted online . . . . . . . . .yielded a mean growth rate of approximately 5 cm/year, for a total increase in the mean thickness of the Greenland Ice Sheet of about 55 cm over the 11-year period, a result that was just the opposite of that suggested by Alley et al. (M) Then, came the study of Rignot and Kanagaratnam (2005), who used satellite radar interferometry observations of Greenland to detect "widespread glacier acceleration." (NM) This was followed by the satellite radar altimetry study of Zwally et al. (2005), which found that "the Greenland ice sheet is thinning at the margins (-42 ± 2 Gt/year below the equilibrium-line altitude) and growing inland (+53 ± 2 Gt/year above the equilibrium-line altitude) with a small overall mass gain (+11 ± 3 Gt/year; -0.03 mm/year sea-level equivalent)." (M) Chen et al. (2006) with their Gravity Recovery and Climate Experiment (GRACE) study concluded that satellite-measured gravity variations suggested that the Greenland Ice Sheet was currently disappearing at a rate of some 240 cubic kilometers per year. [The GRACE method has received some heavy criticism.] (NM) Joughin et al. (2008) wrote that "surface-melt-enhanced basal lubrication has been invoked previously as a feedback that would hasten the Greenland Ice Sheet's demise in a warming climate." However, their real-world observations of this phenomenon showed that "several fast-flowing outlet glaciers, including Jakobshavn Isbrae, are relatively insensitive to this process." (NM) Four researchers, Nick et al. (2009) developed "a numerical ice-flow model that reproduced the observed marked changes in Helheim Glacier," which they described as "one of Greenland's largest outlet glaciers," after which they used the model to study the glacier's dynamics and determine what they might imply about the future mass balance of the Greenland Ice Sheet and subsequent global sea levels. They concluded that "tidewater outlet glaciers adjust extremely rapidly to changing boundary conditions at the calving terminus," stating that their results implied that "the recent rates of mass loss in Greenland's outlet glaciers are transient and should not be extrapolated into the future." (NM)Wake et al. (2009) reconstructed the 1866-2005 surface mass-balance (SMB) history of the Greenland ice sheet in order to compare "the response of the ice sheet to a recent period of warming and a similar warm period during the 1920s to examine how exceptional the recent changes are within a longer time context." And in doing so, the six scientists determined that present-day SMB changes "are not exceptional within the last 140 years." In fact, they found that the SMB decline over the decade 1995-2005 was no different from that of the decade 1923-1933. Therefore, "based on the simulations of these two periods," according to Wake et al., "it could as well be stated that the recent changes that have been monitored extensively (Krabill et al., 2004; Luthcke et al., 2006; Thomas et al., 2006) are representative of natural sub-decadal fluctuations in the mass balance of the ice sheet and are not necessarily the result of anthropogenic-related warming." (NM) At the same time, Ettema et al. (2009) revealed the "total annual precipitation in the Greenland ice sheet for 1958-2007 to be up to 24% and surface mass balance up to 63% higher than previously thought," with the largest differences occurring in coastal southeast Greenland, where the seven scientists said that the much higher-resolution facilitates captured snow accumulation peaks that past five-fold coarser resolution regional climate models missed. With respect to the stability/longevity of the Greenland Ice Sheet, therefore, Ettema et al. state that "considerably more mass accumulates on the Greenland Ice Sheet than previously thought, adjusting upwards earlier estimates by as much as 63%," which suggests that the Northern Hemisphere's largest ice sheet may well hang around a whole lot longer than we might think. Then there is the Antarctic the other large ice mass.. Zwally et al. (2005), deriving data from ice surface elevation changes based on nine years of satellite radar altimetry data determined Antarctica's contribution to mean global sea level over a recent nine-year period to be 0.08 mm/year compared to the five-times-greater value of 0.4 mm/year calculated by Velcogna and Wahr (2006). (Look out, New York!) Ramillien et al. (2006) derived new estimates of the mass balances of the East and West Antarctic Ice Sheets that were also based on GRACE data, but which pertained to the somewhat shorter period of July 2002 to March 2005, obtaining some significantly different ice sheet mass balances than those obtained by Velicogna and Wahr: a loss of 107 ± 23 km3/year for West Antarctica and a gain of 67 ± 28 km3/year for East Antarctica, which results yielded a net ice loss for the entire continent of only 40 km3/year (which translates to a mean sea level rise of 0.11 mm/year. Shepherd and Wingham (2007) reviewed what was known about sea-level contributions arising from the wastage of the Greenland and Antarctic Ice Sheets, concentrating on the results of 14 satellite-based estimates of the imbalances of the polar ice sheets that had been derived since 1998. They yielded a diversity of values, ranging from a sea-level rise equivalent of 1.0 mm/year to a sea-level fall (!!!) equivalent of 0.15 mm/year. The two researchers concluded that the current "best estimate" of the contribution of polar ice wastage to global sea level change was a rise of 0.35 millimeters per year, which over a century amounts to only 35 millimeters or, if you prefer 1.38". New York set to be big loser as sea levels rise The defense rests. Harry ****************************** Henry George School of Los Angeles Box 655 Tujunga CA 91042 (818) 352-4141 ****************************** Sent: Friday, April 08, 2011 9:39 AM Subject: [Futurework] BBC News - New York set to be big loser as sea levels rise http://www.bbc.co.uk/news/science-environment-13011073 8 April 2011 Last updated at 08:00 ET New York set to be big loser as sea levels rise Richard Black <http://www.bbc.co.uk/media/images/50221000/jpg/_50221822_rb112.jpg> By Richard Black Environment correspondent, BBC News, Vienna New York (Image: BBC) <http://news.bbcimg.co.uk/media/images/52068000/jpg/_52068811_nybbc.jpg> Places like New York are projected to experience an above average sea level increase · New York is a major loser and Reykjavik a winner from new forecasts of sea level rise in different regions. The Intergovernmental Panel on Climate Change (IPCC) said in 2007 that sea levels would rise at least 28cm (1ft) by the year 2100. But this is a global average; and now a Dutch team has made what appears to be the first attempt to model all the factors leading to regional variations.
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