World View of Global Warming is an independent documentary project by photojournalist Gary Braasch, now in its 11th year, presenting a comprehensive look at global warming science, the world wide effects of climate change, its implications, and what action is being taken about it. Braasch documents this change through science reporting and photography from the Arctic to Antarctica, from glaciers to the oceans. Rapid climate change is occurring now and its effects are fast becoming one of the prime events of the 21st century.
What Causes Global Warming?
Scientists have spent decades figuring out what is causing global warming. They've looked at the natural cycles and events that are known to influence climate. But the amount and pattern of warming that's been measured can't be explained by these factors alone. The only way to explain the pattern is to include the effect of greenhouse gases (GHGs) emitted by humans.To bring all this information together, the United Nations formed a group of scientists called the International Panel on Climate Change, or IPCC. The IPCC meets every few years to review the latest scientific findings and write a report summarizing all that is known about global warming. Each report represents a consensus, or agreement, among hundreds of leading scientists.
One of the first things scientists learned is that there are several greenhouse gases responsible for warming, and humans emit them in a variety of ways. Most come from the combustion of fossil fuels in cars, factories and electricity production. The gas responsible for the most warming is carbon dioxide, also called CO2. Other contributors include methane released from landfills and agriculture (especially from the digestive systems of grazing animals), nitrous oxide from fertilizers, gases used for refrigeration and industrial processes, and the loss of forests that would otherwise store CO2.
Different greenhouse gases have very different heat-trapping abilities. Some of them can even trap more heat than CO2. A molecule of methane produces more than 20 times the warming of a molecule of CO2. Nitrous oxide is 300 times more powerful than CO2. Other gases, such as chlorofluorocarbons (which have been banned in much of the world because they also degrade the ozone layer), have heat-trapping potential thousands of times greater than CO2. But because their concentrations are much lower than CO2, none of these gases adds as much warmth to the atmosphere as CO2 does.Most Causes of Global Warming
- Carbon dioxide emissions from fossil fuel burning power plants
- Carbon dioxide emissions from burning gasoline for transportation
- Methane emissions from animals, agriculture such as rice paddies, and from Arctic seabeds
- Deforestation, especially tropical forests for wood, pulp, and farmland
- Increase in usage of chemical fertilizers on croplands
- Rise in sea levels worldwide
- More killer storms
- Massive crop failures
- Widespread extinction of species
- Disappearance of coral reefs
Causes of Global Warming
Scientists have determined that a number of human activities are contributing to global warming by adding excessive amounts of greenhouse gases to the atmosphere. Greenhouse gases such as carbon dioxide accummulate in the atmosphere and trap heat that normally would exit into outer space.Greenhouse Gases and Global Warming
While many greenhouse gases occur naturally and are needed to create the greenhouse effect that keeps the Earth warm enough to support life, human use of fossil fuels is the main source of excess greenhouse gases. By driving cars, using electricity from coal-fired power plants, or heating our homes with oil or natural gas, we release carbon dioxide and other heat-trapping gases into the atmosphere. Deforestation is another significant source of greenhouse gases, because fewer trees means less carbon dioxide conversion to oxygen.The Consequences of Global Warming
As the concentration of greenhouse gases grows, more heat is trapped in the atmosphere and less escapes back into space. This increase in trapped heat changes the climate and alters weather patterns, which may hasten species extinction, influence the length of seasons, cause coastal flooding, and lead to more frequent and severe storms.How Do You Contribute?
If you want to help stop global warming, you have to understand how your actions are causing it. The main causes of global warming, in order of the magnitude of their impact, are:Carbon Dioxide from:
- Fossil Fuel
- Failing Sinks
- Cattle and Rice Paddies
- the Artic Tundra