More on Global Warming

Open Email to:
Rep. John Shimkus, Chairman House Subcommittee on the Environment and Economy.
Sen. Barbara Boxer, Chairwoman Senate Environment and Public Works Committee.
Sen. David Vitter, Member Senate Environment and Public Works Committee. 

Dear Rep. Shimkus and Senators Boxer and Vitter,

There are two main questions regarding global warming.
1. Is there global warming?
2. If there is global warming, what caused it?

Answer to #I:
Yes. There is global warming and also global cooling. Archaeological information has shown that in the Earth's history, there have been long periods of global temperatures higher than average and also lower than average.
In the present cycle, there has been no average increase in global warming over the past 17 years. http://dailycaller.com/2013/12/20/the-top-seven-global-warming-alarmist-setbacks-in-2013/ .
As we approach the end of the year, it also appears clear that 2013 will finish as one of the 10 coldest years in US history. Real Science shows a graph of the yearly average highs and lows. It is projected that 2013 will close as the ninth lowest average temperature since 1890.
http://stevengoddard.wordpress.com/2013/12/20/2013-one-of-the-ten-coldest-years-in-us-history-with-the-largest-drop-in-temperature/ .

Answer to #2:
We know that the average global temperature has varied drastically over the past millennia. This variation mostly occurred during the time of little or no human activity. Climatologists have considered that variation as caused by natural forces, such as variations in the Sun's radiation output, variable distance from Earth to Sun, variable volcanic activity, etc..
In no instance were those large global temperature variations attributed to carbon dioxide concentration in the atmosphere. The latter supposition has been developed only in modern times and is not supported by data nor theory. The average global temperatures of the Earth have not increased over the past 17 years, despite a continuing increase in carbon dioxide emissions from the burning of carbon containing fuels.
In addition, no satisfactory mechanism has been proposed, which could explain how the low concentration of 0.05% carbon dioxide in the atmosphere could affect global temperatures.