State of the Earth

Visit: http://video. nationalgeographic Choose “Final report: State of the Earth” video to watch (which should begin to play right away)

Evidence of a Changing Climate Scientists believe that the earth’s climate is changing and this change is being caused by human activity Most changes that are occurring have not happened for thousands of years For example: ice that has been frozen on earth for thousands of years is now melting Changes like this are symptoms of global changes in the Earth’s climate Scientists analyze and measure these symptoms of climate change

Rising Temperatures One of the main ways scientists can tell that the climate is changing is by studying past temperature records These historic records show that the averages temperature goes up and down from year to year but also shows long term trends The long term trends shows increases in the overall global temperature with some areas increasing more rapidly than others

Melting Glaciers, Ice sheets and Sea ice As global temperatures rise, the average size of glacier ice decreases Nearly half the people around the world depend on glacier ice melting to supply their freshwater If these melt, serious freshwater shortages could occur around the world

http://faculty.geog.utoronto.ca/Harvey/Harvey/harvey_images.htm

Ice sheets Ice sheets covering Greenland and Antarctica are also melting Compared with 15 years ago, twice as much of Greenland’s surface ice is melting In Antarctica, snow is melting much further inland and at higher altitudes then previous recorded

Greenland Ice Sheet http://www.global-greenhouse-warming.com/melting-greenland.html

Sea ice Arctic sea ice is also disappearing More and more sea ice is melting during the summer Scientists estimate that the Arctic could be entirely ice-free in the summer within a few years

Sea Ice Melting http://weblogs.marylandweather.com/by_the_numbers/

Rising Sea Levels Global sea levels has risen significantly over the past 120 years Since 1993, the sea level has been rising almost twice as fast in the past 30 years Small increases in sea level can result in floods in low-lying countries

Causes of Rising Sea levels When glaciers and ice sheets melt, the water runs into the oceans If the Greenland Ice sheet melted completely the global sea level would raise 7 m Another cause of rising sea levels is due to thermal expansion Thermal expansion is when the volume of water increases slightly when the temperature rises

Other signs of Climate Change Choose one of the following topics to research Changes in Severe Weather Changes in Precipitation Patterns Changes in Seasons Changes in Ecosystems

Research Questions http://www.davidsuzuki.org/Climate_Change/Impacts/ For your chosen topic, identify past and present conditions Predict what will occur if these trends continue Use the following websites for research: http://www.ec.gc.ca/cc/default.asp?Lang=En http://www.adaptation.nrcan.gc.ca/index_e.php http://www.msc-smc.ec.gc.ca/education/scienceofclimatechange/understanding/climate_models/index_e.html http://www.adaptation.nrcan.gc.ca/posters/on/index_e.php http://www.davidsuzuki.org/Climate_Change/Impacts/

Research Presentation Summarize your findings in an clear, precise paragraph. INCLUDE references!!!!

Summary Most of the changes that we are currently seeing in the climate system have not happened for thousands of years Earth’s average temperature has been rising steadily for the past 50 years and overall for the past 100 years The extent of Earth’s glaciers, sea ice, and ice sheets has decreased over the past few decades The rate of sea level rise is increasing Temperature and precipitation patterns are changing as well as the distribution of many plant and animal species

http://video. nationalgeographic http://video.nationalgeographic.com/video/player/environment/preserve-our-planet-env/greenhouse-what-counts-env.html