What is Global Warming?
- Tuesday, 01 July 2008
Our environment is in trouble. Ice caps are melting, catastrophic drought, flooding and mudslides threaten huge areas, and the world's glaciers are rapidly melting. Global warming, carbon dioxide, emissions and greenhouse gases are common buzz words, but what do they really mean? And how will we be affected? The explanation begins with global warming.
What is Global Warming?
Global warming refers to the gradual heating of the atmosphere and includes temperatures on the Earth’s surface. While people living in northern cities might be excited to hear their winters may become warmer over the next few years, the reality is that such a rapid climate change can negatively impact our lives in many other ways.
There are several ways that humans contribute to global warming, and one of the most common is burning fossil fuels such as oil, coal, and natural gas. Fossil fuels are created over millions of years as decayed dead animals and plants are compressed in the ground. We use these fossil fuels to provide evergy for heat, to run our cars, appliances and electronics, and in manufacturing. When fossil fuels are burned to provide energy, various gases and particles, some of which include greenhouse gases, are released into the atmosphere.
Greenhouse gases are the cause of global warming. According to the Department of Energy, greenhouse gases "allow sunlight to enter the atmosphere freely. When sunlight strikes the Earth’s surface, some of it is re-radiated back towards space as infrared radiation (heat). Greenhouse gases absorb this infrared radiation and trap its heat in the atmosphere."
Greenhouse gases warm the Earth’s surface and contribute to climate change. Common greenhouse gases include carbon dioxide, sulfate and methane. The greenhouse effect refers to the warming of the earth because these gasses are trapped in our atmosphere. A major contributor to the greenhouse effect is carbon dioxide.
Emissions refer to the release of gases, liquids, or solids into the atmosphere. Common emissions include carbon dioxide, water vapor, and small particles, such as those found in smoke. Not all emissions are greenhouse gas emissions, but when we talk of climate change or global warming, we are generally referring to emissions that trap heat.
Carbon dioxide is one of the best-known greenhouse gases. A non-poisonous gas that is colorless and odorless, carbon dioxide is released through a number of chemical processes, including when fossil fuels are burned and when humans and animals exhale. Plants, on the other hand, have the opposite impact. They use sunlight to convert carbon dioxide into carbon which is stored in the plant and oxygen which is expelled into the environment.
Concentrations of carbon dioxide in the atmosphere have been steadily increasing in recent decades, in part due to burning of fossil fuels, but also due to deforestation related to logging and land-use changes. With fewer trees and plants to absorb carbon dioxide and produce oxygen, more carbon dioxide stays in the atmosphere where it traps heat.
Who Does Global Warming Affect?
Everyone is affected by climate change, even if people in different areas are affected differently.
Access to drinking water is already a problem for some, and could become a serious probem in many parts of the world if climate change continues unabated. As glaciers disappear and less snow falls in mountainous areas, the availability of clean, fresh water for residential and commercial use is threatened. We are already facing the beginnings of this problem with water shortages and restrictions on watering lawns and crops.
Rising sea levels is another serious problem that will affect millions. As polar ice caps melt, sea levels rise, threatening costal areas and islands that are just above sea level. If climate change continued unabated, the ocean could swallow Manhattan, Florida, the Bay Area in California, Tahiti, the Maldives and many costal areas around the world, displacing hundreds of millions of people.
Many scientists also expect climate change will lead to an increase in extreme weather. Increasingly powerful hurricanes and tornadoes, and devastating drought, flooding and mudslides may very well be in our future
The plant and animal worlds are also affected by climate change. Every species relies on a specific temperature range for survival, so as temperatures rise, plants, wildlife and insects will be able to thrive beyond their current habitat. This could bring into contact species that don't currently have to compete for food, shelter and other resources. Nature's delicate balance has already been upset in the norther United States and Canada, where the pine beetle has thrived in warmer winters, allowing the pest to sweep through thick forests, destroying swathes of trees.
Global warming and climate change is a serious problem. We must act now and do our part to stop polluting and destroying our environment. Protecting the planet we live on today will help our offspring survive in the future.
More on Global Warming and Climate Change:
Green Glossary: Global Warming Potential
Temperatures to Soar in Some U.S. Cities by 2100
Yosemite's Big Trees Disappearing