Text 10340, 115 rader
Skriven 2005-03-27 00:08:22 av Al Jacobs (1:396/17.0)
  Kommentar till text 10321 av John Hull (1:379/1.99)
Ärende: Global Warming
======================
Hello John Hull,

JH> Its called common sense. 

You haven't demonstrated that.  :-)

JH> As for cites, present your own damn credentials.

I defer to the scientists presenting the various studies.  They have
the credentials.  You call it junk science.  But you offer nothing
to support your claims.  

National Science Foundation Press Release 05-043
http://www.nsf.gov/news/news_summ.jsp?cntn_id=103108

Climate Change Inevitable in 21st Century

Even if all greenhouse gases had somehow been stabilized back 
in the year 2000, we would still be committed to a warmer Earth 
and greater sea level rise in the present century, according to a 
new study performed by a team of climate modelers at the 
National Center for Atmospheric Research (NCAR) in Boulder, Colo.

Indeed, say the researchers, whose work was funded by the National
Science Foundation (NSF), globally averaged surface air temperatures
would still rise one degree Fahrenheit (about a half degree Celsius)
by the year 2100, even if no more greenhouse gases were added to the
atmosphere.  And the resulting transfer of heat into the oceans would
cause global sea levels to rise another 4 inches (11 centimeters) from
thermal expansion alone.

The team's findings are published in this week's issue of the journal
Science.

"This study is another in a series that employs increasingly
sophisticated simulation techniques to understand the complex
interactions of the Earth," says Cliff Jacobs of NSF's atmospheric
sciences division.  "These studies often yield results that are 
not revealed by simpler approaches and highlight unintended 
consequences of external factors interacting with Earth's natural 
systems."

"Many people don't realize we are committed right now to a 
significant amount of global warming and sea level rise because of 
the greenhouse gases we have already put into the atmosphere," 
says lead author Jerry Meehl.  "Even if we stabilize greenhouse gas 
concentrations, the climate will continue to warm, and there will be 
proportionately even more sea level rise.  The longer we wait, the 
more climate change we are committed to in the future."

The half-degree temperature rise predicted by the NCAR modelers 
is similar to what was actually observed by the end of the 20th century,
but the projected sea level rise is more than twice the 3-inch
(5-centimeter) rise that was observed then.  Moreover, these forecasts
do not take into account any fresh water from melting ice sheets and
glaciers, which could at least double the sea-level rise caused by
thermal expansion alone.

The models also predict a weakening of the  North Atlantic
thermohaline circulation, which currently warms Europe by 
transporting heat from the tropics.  Even so, Europe heats up along 
with the rest of the planet because of the overwhelming effect of 
greenhouse gases.

Though the study finds signs that the temperature rise will level off   
some 100 years after the greenhouse gases stabilize, it also finds
that ocean waters will continue to warm and expand beyond then,
causing global sea level to rise unabated.

According to the report, the inevitability of climate change results
from thermal inertia, mainly from the oceans, and the long lifetime of
carbon dioxide and other greenhouse gases in the atmosphere. 

Thermal inertia refers to the process by which water heats and cools 
more slowly than air because it is denser than air.

The new study is the first to quantify future "committed" climate
change using coupled global 3-dimensional climate models.  Coupled
models link major components of Earth's climate in ways that allow
them to interact with each other.  Meehl and his NCAR colleagues ran
the same scenario a number of times and averaged the results to create
ensemble simulations from each of two global climate models.  Then
they compared the results from each model.

The scientists also compared possible climate scenarios in the two
models during the 21st century in which greenhouse gases continue 
to build in the atmosphere at low, moderate, or high rates.  The
worst-case scenario projects an average temperature rise of 6.3 0F
(3.5 0C) and sea level rise from thermal expansion of 12 inches (30
centimeters) by 2100.  All scenarios analyzed in the study will be
assessed by international teams of scientists for the next report by
the Intergovernmental Panel on Climate Change, due out in 2007.

Media Contacts:
Anatta, NCAR                   (303) 497-8604     anatta@ucar.edu
Cheryl L. Dybas, NSF      (703) 292-8070     cdybas@nsf.gov

Program Contacts:
Clifford A. Jacobs, NSF   (703) 292-8521     cjacobs@nsf.gov


National Science Foundation
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4201 Wilson Boulevard
Arlington, Virginia 22230, USA
Tel: 703-292-8070
FIRS: 800-877-8339 
TDD: 703-292-5090


.. 


--- Maximus 3.01
 * Origin: New Orleans P.C. Club (1:396/17)