Effects of Global Warming

1. Effects of Global Warming

2. Energy radiates from the earth surface Energy radiates from the atmosphere Greenhouse gases are being warmed by the radiation from earth and “trap heat” Radiation from the sun warms the earth’s surface Withoutgreenhouse gases: -18 degrees! (average temp) Withgreenhouse gases: +15 degrees (average. temp)

3. The average global temperature is about 1 degree warmer today than 100 years ago.

4. Where in Canada has it warmed up the most? The least? Which season shows the biggest change in temperature? Source: Temperature and Precipitation Trends in Canada During the 20th Century Xuebin Zhang,*Lucie A. Vincent, W.D. Hogg and AinNiitsooClimate Research Branch, Meteorological Service of Canada

5. The thermometer is how we measure climate change But it isn’t about the temperature itself. What are the effects?

6. Melting Polar / Glacial Ice • Rising temperatures have caused readily observed melting sea ice.

7. Polar ice caps receding

9. Nearly all glaciers have been receding in the last 100 years.

11. AthabaskaGlacier (Alberta) 1917 2005

14. Greenland

15. Melting Polar Caps – affects the habitat of polar bears which need ice cover in order to hunt their prey (seals) • Inuit also are affected – travelling and hunting on sea ice

16. Albedo • Albedo: the percent of light that is reflected (rather than absorbed) • White objects have a high albedo • Large white objects reflect sun’s radiation back into space. • Examples: Snow, ice, polar ice caps • Dark objects have a low albedo • Examples: oceans / forests • As polar ice caps melt – this lowers Earth’s albedo and more heat is absorbed by the planet…..leading to MORE WARMING!

19. Rising Sea Levels • Caused by melting polar ice caps • Average sea level has risen 10-15 cm in the last 100 years • Next 100 years – predictions are ½ m – 2 meters higher. • Where would rising sea levels have the most effect on people?

21. Predictions vary (a lot!) but even a 1-2 meter rise would mean millions of people have to move.

22. A 100 m rise would, of course be much worse!

24. The Maldives – Indian Ocean

25. Change in Ocean Acidity • Cause – more CO2 in the air leads to more CO2 in the ocean  produces acid. • Threatens the ability of coral to grow, some animals to form shells and fish to reproduce

27. Health Effects • More smog days • Disease increase – some diseases increase in high temperatures (e.g. malaria parasite carried by mosquitoes) • Allergies may increase • Food production changes – where crops are grown

28. Malaria may spread to temperate areas

30. Desertification • Less rainfall in some areas • Water shortages • Longer periods of drought  affecting crops

33. Storm Intensity and Frequency • Increased evaporation  increased rainfall and stronger storms, tornados and hurricanes

36. Precipitation in Canada has increased in some areas and decreased in others.

37. Where we can grow wheat will change!

38. Deforestation • Hot dry summers  • Increase risk of forest fire due to dryer landscapes

39. Shrinking Wetlands • Increased evaporation • Permafrost melts and ponds dry up • Important habitat loss