Concentration increases since 1750:

• Carbon Dioxide: 280 ppm 360 ppm (29%)
• Nitrous Oxides: 280 ppb 360 ppb (11%)
• Methane: 0.70 ppm - 1.70 ppm (143%)

• In principle, CFCS are very bad and will dominate the greenhouse gases in our atmosphere if their terrestrial usage remains high. CFC worldwide production, however, has been significantly reduced because of concern about The Ozone Layer depletion.

• Methane is more directly related to food production and population growth so it could also dominate in the near future

• Frozen methane is also found in the Arctic Ice Caps and will be released due to global warming thus exacerbating the problem. This is far more serious that people realize or has been reported.

Data showing the increasing concentration of Greenhouse Gases:

CO₂ is steadily increasing at the rate of about 1 ppm per year

NO_x is leveling off due to pollution abatement on vehicles but this is offset by increasing vehicular traffic

CH₄ is only recently been measured. Rate of increase is about 10 ppb per year. However, since 1 CH₄ molecule is worth 25 CO₂ molecules, the equivalent growth rate in terms of CO₂ is 2.5 ppm. Thus methane may eventually be the dominant enhanced greenhouse gas in our atmosphere. What can we do about this?

Global Warming: Is it Real?

Rise in Atmospheric CO₂:

This is not controversial:

Recent Measurements (on going monitoring)

Recent Ice Core Data

Land Use Changes:

Okay, so now we have a pretty strong indication that atmospheric CO₂ is building up over time. Are there indications that this is leading to a warmer planet?

Again, here is some data:

Temperature Trends:

Tempeature profiles by Month

Predicting the Future very difficult

But the past is an interesting guide:

The data which convinced the scientific community (1999):

Simplest Prediction is increase in global mean temperature. Can We see evidence for this in the Data?

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