A 7/15/13 Reuters article in the UK Guardian has a scary sounding headline about "sea level" rise "per degree of global warming" citing a new PNAS study. The article even quotes the lead author of the PNAS study saying how confident he is of his study's conclusions, that his results are a break from the "uncertainty" of the past, and provide a "robust" number. The author doesn't mention nor is it stated in the Reuters article that the study was an estimate of what things might be like 2000 years from now. You don't find this out unless you read the Abstract of the linked study. The article also doesn't note the overwhelming scientific consensus that global temperatures have been flat for at least 15 years, and that they may or may not rise appreciably in coming decades.
7/15/13, "Sea levels may rise 2.3 metres per degree of global warming, report says," Reuters, via UK Guardian (2.3 meters is approx. 7.5 feet)
Subhead: "Seas will remain high for centuries after temperatures have risen, with the likelihood of more frequent and damaging storms"
(parag. 7): ""In the past there was some uncertainty and people haven't known by how much," Levermann said. "We're saying now, taking everything we know, that we've got a robust estimate of 2.3 meters of rising sea per degree of warming.""....
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The next sentence in the article says 2 meter high sea level flooding could wipe away large parts of Bangladesh and Florida within 86 years. It doesn't say that the 2.3 meters expressed confidently in the preceding sentence referred to 2000 years from now:
"Some scientific studies have projected sea level rise of up to 2 metres by 2100, a figure that would swamp large tracts of land from Bangladesh to Florida."...
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Following is PNAS Abstract linked in Reuters article, citation for 2000 years is near the end:
7/15/13, "The multimillennial sea-level commitment of global warming," PNAS, Levermann, Potsdam, et al.
"Abstract"
"Global mean sea level has been
steadily rising over the last century, is projected to increase by the
end of this century,
and will continue to rise beyond the year
2100 unless the current global mean temperature trend is reversed.
Inertia in the
climate and global carbon system, however,
causes the global mean temperature to decline slowly even after
greenhouse gas
emissions have ceased, raising the
question of how much sea-level commitment is expected for different
levels of global mean
temperature increase above preindustrial
levels. Although sea-level rise over the last century has been dominated
by ocean
warming and loss of glaciers, the
sensitivity suggested from records of past sea levels indicates
important contributions
should also be expected from the Greenland
and Antarctic Ice Sheets. Uncertainties in the paleo-reconstructions,
however,
necessitate additional strategies to
better constrain the sea-level commitment. Here we combine
paleo-evidence with simulations
from physical models to estimate the
future sea-level commitment on a multimillennial time scale
and compute
associated regional
sea-level patterns. Oceanic thermal
expansion and the Antarctic Ice Sheet contribute quasi-linearly, with
0.4 m °C−1 and 1.2 m °C−1 of warming,
respectively. The saturation of the contribution from glaciers is
overcompensated by the nonlinear response of
the Greenland Ice Sheet. As a consequence
we are committed to a sea-level rise of approximately 2.3 m °C−1 within the next 2,000 y. Considering the lifetime of anthropogenic greenhouse gases, this imposes the need for fundamental
adaptation strategies on multicentennial time scales."
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4/25/2013 Congressional testimony citing 15 year global warming pause:
Dr. Judith Curry, 4/25/13, "STATEMENT TO THE SUBCOMMITTEE ON ENVIRONMENT COMMITTEE ON SCIENCE, SPACE AND TECHNOLOGY OF THE UNITED STATES HOUSE OF REPRESENTATIVES Hearing on “Policy Relevant Climate Issues in Context," 25 April 2013, Judith A. Curry, Georgia Institute of Technology:
page 3, "Since 1998 there has been no statistically significant increase in global surface temperature. While many engaged in the public discourse on this topic dismiss the significance of a hiatus in increasing global temperatures because of expected variations associated with natural variability, analyses of climate model simulations find very unlikely a plateau or period of cooling that extends beyond 17 years in the presence of human-induced global warming....Others have suggested that the pause could last up to two decades (11) or even longer, owing to the transition to the cool phase of the Pacific Decadal Oscillation that is associated with a predominance of La Nina (cool) events."...footnote 11, Aug.-Sept. 2009, "Advancing Climate Prediction Science," WMO, Geneva (p. 3 graph shows cooling in early 2000's)
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UN IPCC Chief notes 17 year pause in global warming:
2/21/13, “IPCC Head Pachauri Acknowledges Global Warming Standstill,” The Australian, Graham Lloyd
"The UN’s climate change chief, Rajendra Pachauri, has acknowledged a 17-year pause in global temperature rises, confirmed recently by Britain’s Met Office."...
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UK Met Office notes pause in global warming since 1998:
1/18/13, “Climate change: scientists puzzle over halt in global warming,” Der Spiegel, by Axel Bojanowski (translation from German)
"The British Met Office forecast even more recently that the temperature interval could continue at a high level until the end of 2017 - despite the rapidly increasing emissions of greenhouse gases . Then global warming would pause 20 years."..."The exact reasons of the temperature standstill since 1998, are not yet understood, says climate researcher Doug Smith of the Met Office."...
UK Met Office chart via Der Spiegel
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Comment: Reuters and UK Guardian articles citing new studies of alleged CO2 terror can trigger billions of dollars changing hands. It's important the articles not be grossly misleading.
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