I will add the following to my post above pulled it from a History of the Greenhouse Effect and Global Warming Article. It may not be a coincidence or not that in 1988 it was acknowledged that the climate was warmer driving Shell's response while at the same time they funded research into the causes.
In the late 1950's and early 1960's Charles Keeling used the most modern technologies available to produce concentration curves for atmospheric CO2 in Antarctica and Mauna Loa. These curves have become one of the major icons of global warming. The curves showed a downward trend of global annual temperature from the 1940's to the 1970's. At the same time ocean sediment research showed that there had been no less than 32 cold-warm cycles in the last 2,5 million years, rather than only 4. Therefore, fear began to develop that a new ice age might be near. The media and many scientists ignored scientific data of the 1950's and 1960's in favor of global cooling.
In the 1980's, finally, the global annual mean temperature curve started to rise. People began to question the theory of an upcoming new ice age. In the late 1980's the curve began to increase so steeply that the global warming theory began to win terrain fast. Environmental NGO's (Non-Governmental Organizations) started to advocate global environmental protection to prevent further global warming. The press also gained an interest in global warming. It soon became a hot news topic that was repeated on a global scale. Pictures of smoke stags were put next to pictures of melting ice caps and
flood events. A complete media circus evolved that convinced many people we are on the edge of a significant
climate change that has many
negative impacts on our world today. Stephen Schneider had first predicted global warming in 1976. This made him one of the world's leading global warming experts.
In 1988 it was finally acknowledged that climate was warmer than any period since 1880. The greenhouse effect theory was named and Intergovernmental Panel on Climate Change (IPCC) was founded by the United Nations Environmental Programme and the World Meteorological Organization. This organization tries to predict the impact of the greenhouse effect according to existing climate models and literature information. The Panel consists of more than 2500 scientific and technical experts from more than 60 countries all over the world. The scientists are from widely divergent research fields including climatology, ecology, economics, medicine, and oceanography. The IPCC is referred to as the largest peer-reviewed scientific cooperation project in history. The IPCC released climate change reports in 1992 and 1996, and the latest revised version in 2001.
In the 1990's scientists started to question the greenhouse effect theory, because of major uncertainties in the data sets and model outcomes. They protested the basis of the theory, which was data of global annual mean temperatures. They believed that the measurements were not carried out correctly and that data from oceans was missing. Cooling trends were not explained by the global warming data and satellites showed completely different temperature records from the initial ones. The idea began to grow that global warming models had overestimated the warming trend of the past 100 years. This caused the IPCC to review their initial data on global warming, but this did not make them reconsider whether the trend actually exists. We now know that 1998 was globally the warmest year on record, followed by 2002, 2003, 2001 and 1997. The 10 warmest years on record have all occurred since 1990.
