[uptoolate]

"The Tunguska Event was just such an event, and coincides with the period of time during which global temperatures appear to have been rising the most steadily - the twentieth century."

Do we know for sure that the temperature has only been steadily rising for the last 100-150 years. How do we know it hasn't been rising for the last 300, 500, 1000, 2000, 5000, 10,000, or a million years? Or how do we know that it doesn't have a fluctuation cycle that it goes through every 200 years?

[BallyBill]

How do we know it hasn't been rising for the last 300, 500, 1000, 2000, 5000, 10,000, or a million years?

Dennis Miller's HBO special bought up the reliability of temps taken 100 years ago. I think he talked about a guy taking a thermometer with him on the way to the outhouse and that is what we're using as proof of Global Warming!!

[festus]

Impossible. Tunguska was clearly Tesla trying to contact that polar expedition from his tower and it all went badly wrong.

I read it on the internet so it must be true.

[Robert A Cook PE]

In this case, he's proposing that the global warming "ramp" IS only a few dozen years old - that the essentially "flat" PREVIOUS many hundred (thousand) years only began ramping up AFTER the Tunguska comet collision.

In other words he's explicitly NOT claiming any other reason for previous warming and cooling years, which clearly happened - see the Ice Ages, and the many significant climate changes BETWEEN the Ice Ages that obviously are NOT due to man's influence.

What has stymied (up to now !?!) people who do NOT blame the current global warming (about 1/5 of one degree is all that can be actually measured!) on man's (the US's) burning of fossil fuels is that no specific other cause can be found.

With the Tunguska comet impact, there IS an event that could cause 100 years of slowly warming climates.