ot been a significant rise in temperature at all. Land-based weather stations measured a temperature increase of 0.45C in the last 100 years. This increase could very well just be a normal variation. Also, the instruments used to measure these temperatures were not advanced technology. They also did not take many factors into account. Land-based measurements showed that 1997 was the warmest year ever recorded. However, satellites and weather balloons recorded temperatures that show that 1997 was the seventh coolest year recorded. This records began in 1978. Temperature records that are land-based are too few and they are not spaced evenly. They are not accurate enough. Also, they only record temperatures on land. Only 30% of the Earth is land. 70% of the Earth is left unaccounted for. This type of measurements has many discrepancies. Satellite data, however, is much more accurate. Satellites cover 99% of the earth’s surface, and don’t miss the water bodies. Also, a new satellite is launched before the one prior comes back. The data overlaps to ensure that nothing is missed. The measurements are very accurate, within 0.001C. Satellite records match almost exactly with measurements taken from weather balloons. Records from weather balloons have been recorded since 1960. These measurements also show that there has not been a warming trend since 1979. The temperatures obtained from the satellites were from the lower troposphere is more accurate than surface measurements because the measurements on the surface are only representative of a thin layer of the atmosphere. Most of the greenhouse gases are natural. 98% of these emissions are water vapor. The remaining 2% is the result of human caused pollution. Also, 70% of the warming that had occurred during the last 100 years, happened before 1940. This was before the rise in emissions from industry and vehicles.I believe that the reason for global warmin...
