Now we know why Hansen et al needed "stagecraft" to sell the global warming hoax in 1988: "in the U.S. "warming hole," temperatures decreased by as much as 1 degree Celsius during the period 1930–1990"

NewsRoomAmerica.com - "Warming hole" Delayed Climate Change Over Eastern United States

(Newsroom America) -- Climate scientists at the Harvard School of Engineering and Applied Sciences (SEAS) have discovered that particulate pollution in the late 20th century created a "warming hole" over the eastern United States — that is, a cold patch where the effects of global warming were temporarily obscured.

While greenhouse gases like carbon dioxide and methane warm the Earth's surface, tiny particles in the air can have the reverse effect on regional scales.

"What we've shown is that particulate pollution over the eastern United States has delayed the warming that we would expect to see from increasing greenhouse gases," says lead author Eric Leibensperger (Ph.D. '11), who completed the work as a graduate student in applied physics at SEAS.

...Since the early 20th century, global mean temperatures have risen—by approximately 0.8 degrees Celsius from 1906 to 2005—but in the U.S. "warming hole," temperatures decreased by as much as 1 degree Celsius during the period 1930–1990. U.S. particulate pollution peaked in 1980 and has since been reduced by about half. By 2010 the average cooling effect over the East had fallen to just 0.3 degrees Celsius.

..."No one is suggesting that we should stop improving air quality, but it’s important to understand the consequences. Clearing the air could lead to regional warming," Mickley says.

Stagecraft - By Chris Horner - Planet Gore - National Review Online

TIMOTHY WIRTH: We called the Weather Bureau and found out what historically was the hottest day of the summer. Well, it was June 6th or June 9th or whatever it was. So we scheduled the hearing that day, and bingo, it was the hottest day on record in Washington, or close to it.

DEBORAH AMOS: [on camera] Did you also alter the temperature in the hearing room that day? 

TIMOTHY WIRTH: What we did is that we went in the night before and opened all the windows, I will admit, right, so that the air conditioning wasn’t working inside the room. And so when the- when the hearing occurred, there was not only bliss, which is television cameras and double figures, but it was really hot.[Shot of witnesses at hearing]

WIRTH: Dr. Hansen, if you’d start us off, we’d appreciate it. The wonderful Jim Hansen was wiping his brow at the table at the hearing, at the witness table, and giving this remarkable testimony.[nice shot of a sweaty Hansen]