Transcript Climate Change S

Global Warming – Climate Change
Who Cares?
image at: communities.canada.com/vancouversun/blogs/the...
Global Warming – Climate Change
Who Cares?
However - this is a Scientific problem
and Science deals only with evidence
and assessment of evidence to the best
of our honest (disinterested) ability.
4/5
NOW
at: www.personal.psu.edu/ebt5007/hmwk3.html
http://www.coolantarctica.com/Antarctica%20fact%20file/scie
nce/Mauna_Loa_Carbon_Dioxide.png
+0.8oC
since
1860
1979
2004
The Arctic may be ice free by 2040 - the first
time in a million years.
The Arctic ice cap has shrunk over the last four years
1992
2002
The areas of Greenland that melt in summer have expanded
(orange) in recent years.
McCarty Glacier in Alaska. Evidence of global warming?
Triftgletscher in Switzerland until recently filled the entire basin seen here.
Thinning of the tongue during the 1990s accelerated and as of 2001 a lake
started to form in front of it. Rapid break-up of the snout is now underway. Image:
Glaciers Online/Jürg Alean
1948
2002
2006
Trift Glacier - Oberland Switzerland showing glacier retreat
at: www.personal.psu.edu/ebt5007/hmwk3.html
This graphic shows the height of the Greenland ice sheet at present
(left) and during the last interglacial (about 130,000 years ago),
The CCSM suggests that during the interglacial period, meltwater from
Greenland and other Arctic sources raised sea level by as much as 11
feet (3.5 meters),
However, coral records indicate that the sea level actually rose 13 to 20
feet (4-6 meters) or more probably due to Antarctic melting
This might be accelerated by global-scale greenhouse-induced
warming year round,
In the last few years sea level has begun rising more rapidly, now at a
rate of about an inch per decade
Recent studies have also found accelerated rates of glacial retreat
along the margins of both the Greenland and West Antarctic ice sheets.
at: www.personal.psu.edu/ebt5007/hmwk3.html
This graphic shows the height of the Greenland ice sheet at present (left) and
during the last interglacial (about 130,000 years ago), as simulated by the
NCAR-based Community Climate System Model coupled with an ice-sheet
model. (Illustration courtesy Bette Otto-Bliesner, NCAR.)"Getting past climate
change correct in these models gives us more confidence in their ability to
predict future climate change," says Otto-Bliesner.
The CCSM suggests that during the interglacial period, meltwater from
Greenland and other Arctic sources raised sea level by as much as 11 feet
(3.5 meters), says Otto-Bliesner. However, coral records indicate that the sea
level actually rose 13 to 20 feet (4-6 meters) or more. Overpeck concludes that
Antarctic melting must have produced the remainder of the sea-level rise.
These studies are the first to link Arctic and Antarctic melting in the last
interglacial period. Marine diatoms and beryllium isotopes found beneath the