2. Radiation The radiation is trapped inside the atmosphere when it is received in the highest layer in the atmosphere Some of the radiation is reflected off clouds and into space The radiation that goes into the atmosphere is absorbed by oxygen and water vapor Radiation that comes back to Earth from clouds is absorbed by greenhouse gases The radiation that reaches the Earth is not all used in its surface because some of it is absorbed by seas and oceans If the Earth gets more clouds, more radiation will be reflected back into space and less will reach the surface
3. Greenhouse Gases Each CO2 molecule consist of one carbon atom with an oxygen atom bonded to each side The carbon dioxide molecule absorb radiation and the molecule starts to vibrate The vibrating molecule would absorb radiation again and it would be absorbed by another greenhouse gas molecule Carbon Dioxide is recycled through photosynthesis Carbon dioxide goes into the air when humans breathe out, burn fossil fuels for energy, and deforest the planet
4. Fossil Fuels Fossil fuels contain carbon and when they are burned, they combine with oxygen to form CO2 Oil burning is responsible for 30% of all CO2 in the air Natural gas doesn’t release as much CO2 because of its methane structure Coal and oil are composed with more complex molecules which mean that they release ash particles into the environment that doesn’t burn which are carried to the atmosphere and cause pollution Natural gases releases small levels of CO2 and no ash
5. Climate Change Higher temperatures are caused by more greenhouse gases in the environment Sea levels rise due to melting glacier ice and expansion of warmer water Warmer waters in the oceans caused the death of a quarter of the world’s coral reefs With more moisture in the air, precipitation occurs which can lead to flooding Higher temperatures cause evaporations and more droughts because more water is soaked up There are more frequent heat waves The Antarctic Peninsula warmed 5 times faster than the global average The warm moisture from waters caused more hurricanes The weather causes changes in which plants and animals can live and loss of water supplies that come from glaciers
6. Proof of Global Warming Each year, the temperature increase by 5 degrees Celsius More than a million square kilometers of sea ice were missing in the summer of 2007 compared to the previous year June’s land and sea surface temperatures were the second hottest record over the past decade Study shows that the troposphere was warming 0.2 degrees Celsius The stratosphere is cooling 5 times faster than the troposphere is warming which means that there’s an increase of greenhouse gases
7. The Kyoto Accord The Kyoto Accord wanted to decrease overall greenhouse gases among the nations The United States and Australia refused to confirm the treaty but still are expected to take some methods To stabilize CO2 levels, total greenhouse gas emissions must be cut by 60-80% within 50 years Under the Kyoto, the European Union must reduce emissions by 8% The United States refused to confirm it but committed to a 7% reduction The United States increased the gas emissions by 0.7 % in 2002
8. Debate About Global Warming Some scientists say that some of the results of short-term weather conditions and not long-term climate trends and they say that human disruption of natural warming cycles possibly won’t affect sea levels Policy makers have a hard time deciding about what the countries should do to limit greenhouse gases in case global warming is caused from them
9. United States Producing Greenhouse Gases United States uses a lot of deforestation which means that people are clearing new land for farming and pastures used for animals Trees absorb carbon but we cut and burn them down When trees are burnt down, carbon is released into the air and carbon bonds with oxygen to form greenhouse gases We also drive a lot vehicles, which is different from Asia because they usually ride bikes to get somewhere and driving vehicles is burning fossil fuels