• Popular Misconception --> Amazon Rain Forest Destruction greatly contributes to the problem. It doesn't, its the total amount of biomass on the planet that contributes to the Carbon Cycle . The real problem with deforestation is the immediate release of methane. However, detailed studies of gas exchange in rain forest systems indicates that rain forests are net producers of greenhouse gases (due to methane emissions) and not net sinks (e.g. they remove CO₂). This point is a bit controversial still and in any event, is not one that the public believes.

• Evidence of increased hurricane strength is here: Hurricane Andrew ; Elmira in the Pacific

Simplest Prediction is increase in global mean temperature.

Role of clouds is crucial --> Net Cooling or Warming? --> There is general consensus that cloud cover will increase as the capacity for the atmosphere to retain water increases with increasing temperature.

What does the actual data look like?

Long Term Temperature Trends:

• Northern Hemisphere Temperature Trends over the last 100 years
• Southern Hemisphere Temperature Trends over the last 100 years
• World Temperature Trends over the last 100 years
• Summary of Data

• Is the pre-1920 data reliable?
• Increasing number of recording stations since 1950 means non-uniform data quality
• Southern Hemisphere is more ocean to land area than Northern Hemisphere
• But, there does appear to be an 0.5 degree Celsius increase per century in the data

When positional data is combined with temperature data and timesliced in this way - it seems clear the Global Warming is occurring. This conclusion was reached by a National Academcy of Science panel in Sept. 1995 and is accepted by most.

What about the US:

Some Internet Resources:

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