Tuesday, January 10, 2006

Three Catagory 5 Hurricanes Had Lightning Over Ocean

By Elaine Meinel Supkis

Normally, hurricanes have no lightning but this summer, the most ferocious ones had lightning in a most unexpected place: at sea. NASA wonders what happened.

From NASA:
Surprise: During the record-setting hurricane season of 2005 three of the most powerful storms--Rita, Katrina, and Emily--did have lightning, lots of it. And researchers would like to know why.<
"Generally there's not a lot of lightning in the eye-wall region," he says. "So when people see lightning there, they perk up -- they say, okay, something's happening."

Indeed, the electric fields above Emily were among the strongest ever measured by the aircraft’s sensors over any storm. "We observed steady fields in excess of 8 kilovolts per meter," says Blakeslee. "That is huge--comparable to the strongest fields we would expect to find over a large land-based 'mesoscale' thunderstorm."
One of the more interesting features of the hurricanes this year was the incredible speed at which they went from catagory 1 to catagory 4+. Hurricane Wilma took around 90 minutes from catagory 1 to catagory 5! This ia beyond amazing. Frightful. On so many levels, this last hurricane season was a record maker.

The data about the lightning is most interesting. Something was going on between the troposphere and the lower atmosphere right above the ocean. According to NASA, most occasions for lightning in hurricanes happen when they hit mountainous lands. The hills break the wind upwelling and allows lighting to form.

But in this case, the lightning came in a burst at the same time the hurricanes, while over the open ocean with no land anywhere near the system, suddenly grew in strength. The windspeeds were rapidly accelerating and on the leading edges where the rotation was developing the fastest was were the biggest groupings of lightning events. When each hurricane struck land, the lightning was long gone.

I blogged about Katrina in August. As a reminder, here is the satellite image:

It fed off of the Pacific, the Caribbean and the Gulf all at once. This image was taken when it was just finishing off the lightning display.
New Orleans is the latest place in the Eye of the Storm. Last year, when one killer hurricane after another struck Florida and the Gulf coast, each storm slid past New Orleans. The one that nearly hit, they evacuated the city...except for the poor and the elderly who have no trasportation and no where to go. The mayor refused to house them and they survived that death trap only because the dice were rolled and the number was seven, not snake eyes.
Just had to quote myself from last August, days before the hurricane hit New Orleans. I am not President of the USA so of course, they died, didn't they?

But then, the war in Iraq wouldn't be happening, either.
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