Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Giant blue jet caught on film

14.03.2002


Flashes this big might explain the 300,000-volt difference between the ionosphere and the ground


A sprite is like a blue jet but travels the other way.
© Uni. Alaska Fairbanks


Blue jets connect Earth’s electric circuit.

Video images captured in Puerto Rico suggest that blue flashes of light, much like lightning, feed energy from thunderstorms up into the Earth’s ionosphere - a blanket of electrically charged air some 70 kilometres above the ground1.

Some researchers suspect that such phenomena may also fix nitrogen for plants to use and interact with the ozone layer2.



The images, taken in September 2001, show the largest blue jet ever to be caught on camera. "It really was a gigantic flash," says Victor Pasko of Pennsylvania State University, who led the observation team. "With the naked eye you could even see it rising," he recalls.

Blue jets are often associated with thunderstorms, but until now were thought to be relatively small. The Puerto Rican jet stretched from the top of a small thunderstorm to the lower edge of the ionosphere, filling an estimated 6,000 cubic kilometres of atmosphere.

Flashes this big might explain the 300,000-volt difference between the charge of the ionosphere and the ground. Physicists have long agreed that something must link the two regions to complete the global electrical circuit (GEC). Until the latest film, nothing had been seen that reached high enough from the cloud tops to do the job.

"We knew the currents were there, but there was no visual evidence" says Davis Sentman, the physicist at the University of Alaska in Fairbanks who discovered blue jets in 1994. The film "really advances the science in this field", he says.

That the sighting was associated with the kind of small, localized storm common worldwide, suggests that large blue jets could also be common. If so, they might influence atmospheric chemistry: their electrical energy could encourage gases to react with one another. "The effect may be there but we don’t know if it’s dramatically important," admits Pasko.

Sprites, elves, trolls and pixies

In the past decade, high-speed, light-sensitive cameras have allowed scientists to describe a menagerie of electrical phenomena, which bear names that would be more at home in a Tolkien novel than a physics textbook. Sprites, blue jets and associated flashes called elves, crawlers, trolls and pixies are all fleeting electrical discharges that accompany thunderstorms.

All these phenomena are hard to spot, as they last for less than a blink of an eye and are obscured from below by cloud. They can be glimpsed along storm fronts and from aeroplanes flying above the clouds.

Sprites, which might also help to maintain the GEC, work a bit like blue jets in reverse. They are pink, or sometimes red, and occur when current from just below the ionosphere moves downwards towards thunderstorms. As with jets, this current excites atoms along the way, causing them to emit light.

References

  1. Pasko, V. P., Stanley, M. A., Mathews, J. D., Inan, U. S. & Wood, T. G. Electrical discharge from a thundercloud top to the lower ionosphere. Nature, 416, 152 - 154, (2002).
  2. Mishin, E. Ozone layer perturbation by a single blue jet. Geophysical Research Letters, 24, 1919 - 1922, (1997).


TOM CLARKE | © Nature News Service

More articles from Earth Sciences:

nachricht How much biomass grows in the savannah?
16.02.2017 | Friedrich-Schiller-Universität Jena

nachricht Canadian glaciers now major contributor to sea level change, UCI study shows
15.02.2017 | University of California - Irvine

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Switched-on DNA

20.02.2017 | Materials Sciences

Second cause of hidden hearing loss identified

20.02.2017 | Health and Medicine

Prospect for more effective treatment of nerve pain

20.02.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>