Solar Linkages to Atmospheric Processes (SLAP) is an International Polar Year project investigating the links between changes in solar output and weather and climate. Thunderstorms and lightning strikes drive electricity around the world and form part of a global 'atmospheric electric circuit' that flows between the ground and the lower reaches of the ionosphere – about 80km up.
Thunderstorms and electrified clouds are the 'batteries' of the atmospheric electric circuit, which drive the current from the ground to the ionosphere, while lightning is a visual representation of the current. The flow of current around the world is modulated by cosmic rays, which control atmospheric conductivity. (Cosmic rays are in turn modulated by the solar wind). The circuit is completed when the current trickles back to Earth, in regions remote from thunderstorm activity, such as Antarctica.
Through the International Polar Year (IPY) project, Solar Linkages to Atmospheric Processes, Australian Antarctic Division scientist, Dr Gary Burns, and his colleagues Drs Oleg Troshichev and Alexandr Frank-Kamenetsky of the Arctic and Antarctic Research Institute, are measuring the atmospheric circuit high on the Antarctic plateau at Vostok, near the centre of East Antarctica. Instruments have also been deployed at three sites in West Antarctica by Dr Martin Jarvis of the British Antarctic Survey and another will be deployed at the French-Italian station, Concordia, at Dome C, in January 2009.
Meteorological and solar variability influences on the atmospheric circuit are well established (see box below). The question now is whether the electric circuit actively links solar variability and weather, or if it responds passively to both meteorological and solar variations. Understanding this interaction is important because changes in the global electric circuit, caused by solar variability, could alter the conditions under which thunderstorms develop. Recent results from Dr Burns and his colleagues support an active link.
A theory under investigation is that current flowing through the atmospheric electric circuit influences cloud formation. Measurement of the circuit will enable investigation of the cloud microphysics processes and meteorological responses (such as thunderstorms) at sites around the world.
Accurate measurements of the atmospheric electric circuit could also enable scientists to monitor changes in global thunderstorm activity as the world warms.
'It's thought that an increase in temperature of one degree Celsius could increase meteorological electrical activity by 10 percent,' Dr Burns says.
'So changes in the global electric circuit could provide an indication of the way the Earth's weather is changing.'
A model of the global electric circuit has been developed by collaborators at the University of Texas, Dallas, incorporating variations in cosmic rays, energetic particles, natural radioactivity and aerosols. Outputs from the model will be compared with measured atmospheric circuit responses to these variations, to refine understanding of the processes involved.
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Measuring the atmospheric electric circuit
The atmospheric electric circuit responds quickly to global thunderstorm activity. Thunderstorms preferentially occur in summer, over land in the equatorial and mid-latitude regions and in the local afternoon (see for example http://thunder.msfc.nasa.gov/data/OTDsummaries).
Despite this, the global variation in the atmospheric circuit, due to meteorological influences, is the same everywhere at the same time (because the ionosphere and the earth are so conductive that the influence of all meteorological electrical activity is rapidly integrated).
At good sites (those with low local daily variations in atmospheric conductivity, such as the Antarctic plateau) the average daily variation in the electric circuit reflects the distribution of land across the globe. For example, in the figure above, 20UT (Universal Time or Greenwich Mean Time) corresponds to when thunderstorm activity peaks over the Americas, 15UT is Africa and Europe, 8UT is Australia and Asia and the minimum around 3UT corresponds to local afternoon in the Pacific, where there is little land area and thus relatively few thunderstorms.
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Project contact: Dr Gary Burns +613 6232 3381;
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Media contact: Patti Lucas +613 6232 3514
Related links:
Meet Evgeny Gruzinov, a leading engineer-geophysicist of the Russian Antarctic Expeditions (RAE), who has been working on the Solar Linkages to Atmospheric Processes project.
Solar Linkages to Atmospheric Processes
International Polar Day - Meet the Scientists
International Polar Day - international web site
Australia in the International Polar Year
SLAP project in the Australian Antarctic Magazine
Arctic and Antarctic Research Institute
MEET EVGENY GRUZINOV
Evgeny Gruzinov is a leading engineer-geophysicist of the Russian Antarctic Expeditions (RAE), who has been working with Dr Gary Burns, of the Australian Antarctic Division, and Drs Oleg Troshichev and Alexandr Frank-Kamenetsky of the Arctic and Antarctic Research Institute (AARI), on the Solar Linkages to Atmospheric Processes (SLAP) project. Evgeny is currently based at the Russian Antarctic station, Vostok, where, among other things, he runs and services the equipment used in the project. For International Polar Day - Above the Polar Regions, we asked him a few questions about his life and work in Antarctica and Russia.
What region of Russia are you from?
I am from Saint-Petersburg, where the headquarters of the Russian Antarctic Expedition (RAE) are located.
What is your job with RAE?
I work in the 53rd RAE and I carry out several scientific programs at the polar station Vostok, namely the observations of the atmospheric electric field variations, research on geomagnetism, seismic research and seismomonitoring.
What is your role in the SLAP project?
I service the scientific equipment the Electric Field Mill (EFM). Every day I send EFM via satellite communication to the Australian Antarctic Division (AAD). Once a month I send EFM calibration data and a report to research managers of the program.
How did you get involved in the SLAP project?
I was trained for it by research managers of the SLAP project – Alexander Frank-Kamenetsky (RAE) and Gary Burns (AAD) - in 2005, and I was invited to carry out this scientific program in the 51st and the 53rd RAE at the polar station Vostok.
What studies have you undertaken?
I graduated from the St. Petersburg University of Telecommunications in 1990, majoring in telecommunications engineering. In 2003 I completed a Masters of Business Administration program at the International Banking Institute, specialising in anti-crisis management. In 2005, I completed the management course at the St. Petersburg State University.
How did you travel to Vostok and how do you get home?
To get to Vostok from St. Petersburg I travelled aboard the scientific expedition ship Academic Federov to the polar station, Progress, with intermediate stops in Bremerhaven (Germany) and Cape Town (Republic of South Africa). From Progress I flew to Vostok. My way home will be the same, only from Cape Town I will fly to St. Petersburg.
How long will you spend at Vostok?
I will spend a complete calendar year here - from 25 December 2007 to 25 December 2008.
What is the coldest it has been while you have been at Vostok?
During this winter at Vostok I experienced the coldest temperature in my life: minus 84.1 degrees Celsius on 27 August.
What do you enjoy and what do you miss at Vostok?
I very much enjoy my scientific work and the unique conditions in Antarctica. The physical isolation for a long time from the family and friends afflicts me a little.
How do you relax at Vostok?
During my free time I watch stations films (we have nearly 2000 films available). I read books (there are about 50 000 e-books available at the station). I play pool and computer games. I am also engaged in photo and video-tape editing, I work out in the gym and I do yoga.
What do you hope for your future career?
I hope to become the chief manager of the polar station and to participate actively in the organisation, preparation and carrying out of future Russian Antarctic expeditions.