Arctic ice sheet melting….its effects on global warming

Atreyee Bhattacharya

EPS 131

Overview of the talk

Why should be study the Arctic?

How do we study the melting of arctic sea ice

The findings of the study

Conclusions and predictions

………..the ignored danger!

• Decreasing albedo

• Warmer oceans & warmer atmosphere

• Ice sheet melting

• Fresh water deluge

• Shutdown of thermohaline circulation

• Drastic cooling

The decay rate

• Image NOAA

                                          

                                          

                                           

    

                                    

       

                                    

       

                                    

            

How fast Is the ice melting(using ice drafts)

• How do we know that the arctic ice sheet has dwindled?

• Answer) Ice drafts

3 m 2 m~ volume is down by some

40%.~ area shrunk by 6%

• SCICEX data,1999• Rothrock et al 1999

The ice is melting probably because…

multi-decadal cycle ?

OR

continue the observed  decline? Answer : Greenhouse gas concentration!!

Effects on ecology and mankind

1.Changes in migration patterns and habitat of terrestrial and marine mammals.

2.Changes in the availability of food resources for sea birds and marine life.

3. Changes in storm surges, shore erosion, and wind.

……..implies recent effects as observed in 1996

4. Changes in precipitation in the summer, fall, and winter

……..implies drying up of traditional food

5. A reduction in sea-ice and changes in the timing of ice formation and thaw in the Bering and Chukchi Seas.

……implies the poor hunting during 1997 and 1998

References

1. Arctic Sea-Ice: Changes, Causes, and ImplicationsUSGCRP Seminar, 20 April 1999

2. 6.Ecology.com3. NOOA4. Ohio State University Department of Mechanical Engineering,

“Science Daily”.5. Rothrock. D.A., Yu. Y. ,& Maykut. G.A.,; Thinning of the Arctic Sea-

Ice Cover. Geophysical Research Letters, Vol. 26,No. 23, pages 3469-3472, December 1, 1999

6. US geological survey

Thank you!!

Questions??