frontier center status of polar bears _ status_of_polar_bears011509.pdf“the polar bear is at risk...
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Status of Polar BearsUrsus maritimus
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Figure TS.23Figure TS.23
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20092006200320001997199419911989198619831980
More Distant IceMore Distant Ice Retreat =
bears summer over deep water
reduced size
poorer survivalpoorer survival ?
Impact onImpact on population size?
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What everybody knows:
“The polar bear is at risk of extinction as global warming meltsextinction as global warming melts away its Arctic sea‐ice habitat. Now it's getting a second chance: polar bears may get protection under the E d d S i A t B t thEndangered Species Act. But the decision is not final.” ‐ CBD
“In some areas of their Arctic home, polar bears are in decline. Th i d i l i b d h d li h fTheir drop in population can be traced to another decline: that of sea ice, reduced by global warming. Sea ice is the polar bears’ primary habitat and they rely on it for survival. Unless major actions to reduce global warming are taken, two‐thirds of the
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g g , fworld’s polar bears are likely to be gone by 2050.” ‐WWF
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Non‐Viablee Popuulationn
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Likelihood of decline with no harvest for Beaufort Sea Polar bears ~ 70%
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Recent Population Studiesp
SB, WH: Decline
NB, SH: Constant
DS, BS: Increase
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Temperature and CO2 from 1997 2007Temperature and CO2 from 1997‐2007
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rature
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Tem
CO2 Co
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Temperature from 2003 to 2008p
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Figure 1: Surface temperatures in the Sargasso Sea, a 2 million square mile region of the Atlantic Ocean, with time resolution of 50 to 100 years and ending in 1975, as determined by isotope ratios of marine organism remains in sediment at the bottom of the sea (3). The horizontal line is the average temperature for this 3,000‐year period. The Little Ice Age and Medieval Climate Optimum were naturally occurring, extended intervals of climate departures from the mean. A value of 0.25 °C, which is the change in Sargasso Sea p , g gtemperature between 1975 and 2006, has been added to the 1975 data in order to provide a 2006 temperature value.
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Positive AO Negative AO
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h l d d f h dThe only documented causes of the recent Arctic warming period were natural and not anticipated by climate models:
Anomalous warm surface water inflow from the North Pacific, Anomalous meridianal (offshore) winds,Enhanced warming from cloud formation over open water and
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Enhanced warming from cloud formation over open water, and Loss of multi‐year ice.
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41Hey, what about us?
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44Sound Conservation Practices
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Solar versus CO2 radiative forcings over the past 150 years: Here is how IPCC suggests that CO2 is dominating!
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Solar versus CO2 radiative forcings over the past 150 years: Why the Sun is a more important climate driver!
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