Climate Change Evidence in Favor of Global Warming...   the changes are becoming less subtle
               from a report in National Geographic - GLOBAL WARMING - Sep. 2004 (Vol 206 No. 3)             




 

 
 


         

 
 
 
 
          A 400,000 year ice core record from Vostok Station, Antarctica, suggest a link between ice ages and the Earth's orbit around the Sun. The Earth's orbit expands and contracts between more circular and more elliptical on 100,000 and 400,000 year cycles. During ice ages the CO2 levels drop. We are in an interglacial period now, which may be extended due to increasing CO2 levels.



 
    

   A measurable consequence includes:
      ARCTIC  SEA  ICE  COVERAGE  IS  SHRINKING
   Arctic sea ice 1979                                       Arctic sea ice Sep 21, 2005

a    Northwest Passage ?

 

 

 

           The NorthWest Passage is a proposed shipping route from the Atlantic to the Pacific
                                          through the Arctic Archipelago of Canada.
From the 15th Century Europeans have searched for such a commercial shipping route. In the summer of 2000 several ships took advantage of the thinning Arctic ice to make this passage. Global warming is assumed to be the cause and it's likely commercial shipping will take advantage of the new NW Passage.
                                                                        

 

 

RISING   SEA   LEVELS

Florida 20,000 years ago    
  

 A consequence of
 polar ice melting &
 warmer seawater is,
 the oceans will rise.

 Models predict rises between a few inches or a few feet over this century.

 There has been a dramatic rise in sea level - 9 inches since 1930, which continues to put So. FL. mangroves under water.
            

 
  
                                                    MARINE  LIFE  IS  DYING                   
SCROLL DOWN

 

Satellite images of Great Barrier Reef -1,240 mile long with 400 species of coral and 1,500 species of fish.

 

 

 

 

 

Coral starts to bleach - a loss of their algae that supply nutrients - in waters warmer than 85-F.

A lethal trend.

 

 

 

Water temps around the Great Barrier Reef in satellite maps rose above the bleaching thresholds in 2002.

The warmest waters (red) caused sever bleaching.

 

              

 
                                                 LAKES :   FEWER  DAYS   FROZEN

 

 

 

  Many lakes are freezing later in the fall and thawing earlier in the spring than in the 1900's.

 

             





  
                                  
   Warming trends in the Swiss Alps results in fewer days         Shifting Reproductive Cycles: Flycatcher birds migrate
   of frost forcing some plants to move upslope to reproduce    from Africa to Holland to nest as they did 20 years ago,
   thereby allowing exotic species to invade downslope.          but warming has changes caterpillar nesting to 2 weeks
                                                                                                  earlier, meaning bird hatchlings may go hungry.

Paleoclimatology...
     the study of past climate in the fossil record: for example, coral reefs & ferns indic-ate warm climate; variations in tree pollen & tree rings also give clues to climate variation, as do oxygen isotopes ratios, 18O/16O.
     As formanifera fossil shells are precipitated, the 18O will be enriched in CaCO3 relative to water and the higher the temp, the less the enrichment.
     Variations in the water temp have been inferred from these oxygen isotope ratios. Ice core
samples can be used to reconstruct palaeoceanographic conditions:   18O of seawater increases as glaciers grow, while removal of low 18O water as glacial ice increases and high 18O in formanifera shells indicates cold temperatures and/or glaciation. 
                                 end