The amount of greenhouse gases in the atmosphere hit a record high in 2012, continuing an ever-faster rise that is resulting in climate change, the United Nations weather agency said on Wednesday.
In an annual report on greenhouse gases, the World Meteorological Organisation (WMO) said concentrations of carbon dioxide, methane and nitrous oxide ‘reached new highs’ last year.
What are greenhouse gases
“Many chemical compounds found in the Earth’s atmosphere act as ‘greenhouse gases’. These gases allow sunlight to enter the atmosphere freely. When sunlight strikes the Earth’s surface, some of it is reflected back towards space as infrared radiation (heat). Greenhouse gases absorb this infrared radiation and trap the heat in the atmosphere,” says the website of Energy Information Administration, the official agency on energy statistics in the US.
“Many gases exhibit these ‘greenhouse’ properties. Some of them occur in nature (water vapour, carbon dioxide, methane, and nitrous oxide), while others are exclusively human-made,” it adds.
How do they affect us
“Over the past century, human activities have released large amounts of carbon dioxide and other greenhouse gases into the atmosphere,” says the US Environmental Protection Agency.
The rise in the level of greenhouse gases results in global warming.