Global Warming is the increase of Earth's average surface temperature due to effect of greenhouse gases, such as carbon dioxide emissions from burning fossil fuels or from deforestation, which trap heat that would otherwise escape from Earth. This is a type of greenhouse effect.
- Melting of ice in the ice dominated areas of earth such as West Antarctica and Greenland, and Arctic sea ice can be seen. These include the melting of mountain glaciers and ice sheets covering.
- The number of Adélie penguins found in Antarctica, has declined from 32,000 breeding pairs to 11,000 in last 30 years.
- An increase in the level of sea has been observed due to melting of sea ice over the last century.
- A number of organisms such as butterflies, foxes, and alpine plants have moved farther north or to higher, cooler areas.
- The average precipitation (rainfall and snowfall) has increased across the globe at a significant rate.
- The number of Spruce bark beetles has increased significantly in Alaska due to continuous warm summers. These insects have destroyed up 4 million acres of spruce trees.
- Rise in Sea levels is expected to be 18 and 59 centimeters by the end of the century, and continued melting at the poles could add between 10 to 20 centimeters.
- Often Hurricanes and other catastrophic storms are likely to become common.
- Species living in a symbiotic relationship may loose their synchronization.
- Conditions of floods and droughts will become more common and often as a result of decrease in the rainfall.
- Availability of fresh water is likely to decrease with time. It is predicted that if the Quelccaya ice cap of Peru continues melting at this rate, it will completely melt by 2100.
- Some diseases will spread such as malaria carried by mosquitoes.
- Eco-systems will be affected to a greater extent leading to extinction and rise of many species.
- Warmer than normal ocean temperatures across the central and eastern tropical Pacific Ocean.
- Increased convection or cloudiness in the central tropical Pacific Ocean - the focus of convection migrates from the Australian/Indonesian region eastward towards the central tropical Pacific Ocean.
- Weaker than normal (easterly) trade winds.
- Low (negative) values of the SOI (Southern Oscillation Index).
- Monitoring these changes help to detect an El Niño event and forecast its lifetime.