“As a follower of the chem/contrail discussion, I wanted to add something about a front page Wall Street Journal article that I saw a few weeks ago
regarding commercial airliners being modified with spraying apparatuses in order to have them on hand to help fight brushfires in the southwest.
I looked through the archives of the WSJ and did not see anything, either.
The problem started back in 2002, when two tanker crashes and a fatal helicopter accident – all in six weeks – led the USFS to appoint a panel to see
what was the best way to keep the pilots from getting killed (www.aviationnow.com...
). The USFS
subsequently cancelled Tanker contracts, which removed 33 large tankers from service -- based on the perceived danger of catastrophic structural
failure during fire-fighting duty (www.Airtanker.com...
gives the tanker pilots’ side of this controversial decision).
Meanwhile, there is already a ready made jet aircraft which can haul 11,000 gallons of liquid to a fire, nearly four times the carrying capacity of
the C-130 Hercules, the largest tanker used by the Forest Service. It is the Ilyushin-76TD, nicknamed the "Waterbomber".
The reason I’m bringing this up is that it simply doesn’t make any sense for the USFS to take existing aircraft out of service, convert them to
water-bombers at an obviously high cost, when there are other aircraft available, designed to do the job, at a much lower cost.
“I have heard the theory that persistent contrail cloud cover is intentionally used to offset the effects of atmospheric warming that are caused by
the greenhouse gas emissions.”
The problem with that is that persistent cloud cover does not offset the effects of greenhouse warming, because persistent cloud cover does not
necessarily result in a net decrease of temperature.
When the days are cloudy, UV rays are blocked, and fewer of them reach the ground. But….
those same clouds at night block the IR on the Earth
from radiating back out to space, so the days are cooler and the nights are warmer.
What cloud cover does is to lower the “diurnal temperature delta”, which is engineering-ese for saying that the difference between the hottest and
coldest part of the 24-hour period is not as great.
And, although cloud cover from persistent contrails are a possible threat to climate, the amount is quite a bit less thatn 20 percent; it is more like
2 percent by 2050, according to my esteemed
colleague Dr. Pat Minnis. Pat and I have corresponded for about the past three or four years, and
he tries to keep me in the loop regarding contrails, since he knows of my interest.
Here is his blurb from the 11th Conference on Atmospheric Radiation back in 2002: ams.confex.com...
[edit on 12-10-2004 by Off_The_Street]