Why would a well-educated Congressperson — perhaps at the same college/university as their liberal peers — pretend to not understand Anthropogenic Global Warming?
As shown in the previous section, prehistoric changes in climate have been very slow. Climate changes typically occur slowly over many millions of years. The climate changes observed today are rapid and largely human-caused. Evidence shows that climate is changing, but what is causing that change? Scientists have suspected since the late 1800s that human-produced (anthropogenic) changes in atmospheric greenhouse gases would likely cause climate change, as changes in these gases have been the case every time in the geologic past. By the middle 1900s, systematic measurements began which confirmed that human-produced carbon dioxide was accumulating in the atmosphere and other earth systems, like forests and the oceans. By the end of the 1900s and into the early 2000’s the Theory of Anthropogenic Climate Change was solidified as evidence from thousands of ground-based studies and continuous satellite measurements of land and ocean mounted in number revealing the expected temperature increase. Theories evolve and transform as new data and new techniques become available, but they represent the state of thinking for that field. The Theory of Anthropogenic Climate Change is that humans are causing most of the current changes to climate by burning fossil fuels such as coal, oil, and natural gas. This section summarizes the scientific understanding of anthropogenic climate change.