Tag Archives: tropical storm

Lightning strikes upward into space, too

upward-lightningHere’s lightning flowing 40 miles up from the top of a storm, to touch the ionosphere. The photos of this phenomenon, called gigantic jets, were taken by Duke University engineer Steve Cummer.

“Gigantic jets are literally lightning that comes out of the thunderclouds, but instead of going down, like most lightning strokes do, these apparently find their way out the tops of thunderclouds, and then keep going and keep going and keep going until they run into something that stops them,” Cummer explained.

He adds:

“…What struck us was the size of this event.”

It appears from the measurements that the amount of electricity discharged by conventional lightning and gigantic jets is comparable, Cummer said.

But the gigantic jets travel farther and faster than conventional lightning because thinner air between the clouds and ionosphere provides less resistance.

The team was actually looking for sprites, “electrical discharges that occur above storm clouds and are colored red or blue, with jellyfish-like tendrils hanging down.”

Spectacle aside, studying the jets could lead to new ways to predict storms. And if nothing else, it’s something for writers to think about when they design their alien atmospheres.

The Gulf Of Mexico becomes Hurricane Alley

Gustav and Hanna are both predicted to be 'big ones'In the sixties, Roger Zelazny wrote ‘Damnation Alley’, in which Hell Tanner drives from Los Angeles to Boston in a land ravaged by near constant hurricanes and tornadoes in an attempt to deliver a life-saving plague vaccine. While we’re nowhere near that doomsday scenario, this year’s hurricane season is certainly hotting up.

Hurricane Gustav is crossing Cuba into the centre of the Gulf of Mexico today, with many of the simulations projecting it to land as a strength three hurricane somewhere in Louisiana on Tuesday night. Meanwhile, a few days further out in the Atlantic tropical storm Hanna (the eighth named storm of the year) is growing steadily and is also projected to land as a hurricane next weekend anywhere from Florida to Mexico. It may or may not enter the Gulf.

Further out than that a number of other weather systems are beginning to form in the infamous ‘hurricane alley’, creating a conveyor belt of large storms. High ocean temperatures of 28-32 degrees in the Gulf of Mexico in particular are increasing the size of intensity of these systems. When the sea temperatures are above 26 degrees, a tropical storm or hurricane above it will intensify. Below that level the cyclone begins to unravel. With Ocean temperatures high and a number of storms forming, the Southeast coast of the US and the caribbean are in for a pounding over the next few weeks. Oil experts are already beginning to predict problems for oil production, with large percentages of US oil production and refining taking place in the Gulf of Mexico. While it would be inaccurate to link a single hurricane to climate change, if tropical ocean temperatures remain high, the residents at the end of hurricane rally will have to expect more storms.

[via The Oil Drum, Gustav weather picture via Weather Underground]