Effects of Increased Global Temperatures What happens to biomes?

Hypothesized Temperature Increase  By 2100, mean global temperature will rise to 15 o C –An average of 2.5 o C  Since 1940 the rise has been 0.6 o C

Arguments to the effects of temperature rise vary

Positive Feedback  Increase in temperature an increase in evaporation to increase in water vapor in atmosphere increase in absorption of infra red radiation increase in temperature increase in evaporation

Negative feedback  Increase in temperaturean increase in evaporation in the tropics to increase in water vapor in atmosphere increase in snow fall at the poles increase in albedo and reflection of light and heat decrease in temperature

Negative feedback  Increase in pollutants increase in reflection of incoming solar insulation decrease in temperature

A rise in Global temperature change can lead to a change in plant and animal distribution and migration patterns

Changing migration patterns  Spread of malarial parasite northwards  Robins in the Artic  Mosquitoes in the Artic  Increase in the number and severity of hurricanes and cyclones

Misnomer?  Is the term Global Warming misleading?  Are all temperatures in all areas of the globe increasing?  What might be a better term?

North America  Grain belt conditions will become drier and warming therefore less productive  Agricultural zones will shift north where weather will be suitable but soil will not.

Melting Polar Ice Caps  Will cause increase in sea levels from 40cm to 200cm by 2100 –1 – 2 cm per year  A result of thermal expansion of water as well as shift from solid ice to liquid water –Results in flooding cities, drowned estuaries, deltas, agricultural land and salt contaminated natural water

Melting Ice Caps  Speculation that the melting of the ice caps will cause in North Atlantic ocean currents that are responsible for the redistribution of the earth’s heat  May result in the stoppage of the Gulf Stream –What changes does this cause?

Reduction of Tundra  Points to decreasing habitat for –Walrus –Polar bear –Penguin –Seals –Many others  Resulting in possible extinctions since rate of temperature change is too rapid for species to adapt

Reduction of Tundra  Currently effects the life and culture of the Inuit  They are no longer able to walk on the thin ice to hunt or construct igloos

Boreal Forests & Tundra  Estimated that the tree line will move northwards by km for every 1 o C rise in temperature  Impacts Scandinavian, Russian, and Canadian forests and tundra biomes

Assignment  Research on global temperatures effects on biomes distribution and global agriculture