Key Facts About Global Warming
This year is set to be the sixth warmest since records began in the 1850s, with 10 of the warmest years in the past 12, according to a British report on Thursday.
The report by the British Meteorological Office and the University of East Anglia linked a gradual rise in temperatures in recent years to greenhouse gases from human activities.
Following are some key facts about global warming:
- "There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities," the UN's Intergovernmental Panel on Climate Change (IPCC) said in its latest report in 2001.
- Concentrations of heat-trapping greenhouse gases in the atmosphere, largely from burning fossil fuels in power plants, factories and vehicles, have risen by more a third since before the Industrial Revolution.
- Concentrations of carbon dioxide, the main greenhouse gas, rose to 379 parts per million (ppm) in 2006 from 280 ppm for the period 1000-1750, the World Meteorological Organization said.
- Temperatures rose by about 0.6 Celsius (1.1 Fahrenheit) during the 20th century and may rise by a further 1.4-5.8 Celsius from 1990 to 2100, a rate of warming without precedent in at least 10,000 years, the IPCC said.
- Rising temperatures are likely to cause more floods, erosion, desertification, heatwaves and drive many species to extinction. Benefits in some regions may include longer growing seasons. Sea levels are likely to rise by 9-88 centimetres (3.5-34.7 inches) from 1990 to 2100, swamping coasts.
- A minority of scientists say the IPCC grossly underestimates the role of natural variations in the climate.