Of the three gases most responsible for current global warming trends, The United Nations Weather Agency reports that levels of two of those gases, carbon dioxide (CO2) and nitrous oxide (N2O), reached record highs in 2006. The third gas, methane, remained stable.
The most prevalent naturally occurring greenhouse gas is water vapor, which is not a major contributor to the climate change the planet is now experiencing.
The concentration of CO2 reached 381.2 parts per million last year, with N2O at 320.1 parts per billion.
The level of CO2 has risen just over 36% since the beginning of the industrial revolution and the large scale burning of fossil fuel. The average global temperature has risen 1.3 degrees Fahrenheit in the past century with 11 of the past 12 years some of the hottest since 1850.
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