3.41 Sspd_chapter 1_appendices_space weather research  (Page 3/3)

Beyond the chromospheres, corona extends up to 10 Solar radii. This has long jets of gas running through it. A large number of energetic ionized hydrogen particles manage to penetrate the magnetosphere. These particles get trapped in the magnetosphere and travel in toroidal path around the magnetic field lines. This belt of trapped particles is called VAN ALLEN BELT.

These ionized particles keep travelling between North&South Magnetic poles of the Earth. At a height from 100 km to 1000 km the inward –rushing or outward –rushing charged particles interact with neutral atmospheric gas particles(Nitrogen&Oxygen).In the process they produce the peak of solar activity. Auroral displays become brighter and solar perturbations are perceptible up to the surface of the Earth.

Depression in corona let matter escape at a speed of 800km/sec. The brief solar flares cause a wind of 1000km/sec. Whereas the eruptions of prominences cause the solar wind to speed up to 2000km/sec.

11 year cycle remains an enigma.

EFFECT OF SOLAR ACTIVITY ON POWER TRANSMISSION&COMMUNICATION

Periodic increase in solar activities in form of increased sun-spots and furious sun-flares lead to major disruptions in power transmissions and communication networks.

August 2, 1972 a 230KV transformer exploded in British Columbia in Canada.

On March 13,1989 , at the peak of Solar Activity, Quebec Province went without power due to failure of the electric transmission network.

October-November 2003 witnessed some of the largest solar flares ever recorded in mankind’s history. The barrage of charged particles forced many satellites to be turned off. Despite this preventive measure many satellites got damaged. Astronauts in international Space Station had to retreat to better shielded portions of their service modules. The air-liners were routed to lower latitudes to prevent communication failure and to protect passenger from unsafe level of radiation exposure. National Transmission Grids had to properly protected against surges. Despite this 50,000 residents in south Sweden faced power failure briefly.

The Global Radio Broadcast at Short Wave RF gets seriously effected due to disruptions of ionosphere surrounding the Earth.

Manned Space Missions can get disrupted. Understanding the solar flares will help the space walkers and astronauts going to Moon&Mars in the coming decade. Astronauts exposed to eruptions can receive a year’s worth of radiation.

Coronal mass Ejections cause Solar Storm. This distorts Earth’s magnetic field. Backlash of charged particles trapped in radiation belts generates massive voltage that can damage satellites and power grids.

THE PATTERN OF SOLAR ACTIVITY

(cooling Sun may bring relief to sweltering Earth-The Hindu)

Sun’s output varies over a cycle of 11 years. When vast amount of energy are being released deep inside&strong magnetic fields rip through the sun’s surface, this is the period of heightened solar activity accompanied with increased number of sun-spots. From 1650 to the end of 1700, the sun-spots almost completely disappeared&Earth experienced little ice again. At this time Thames froze over, Europe shivered&harvest failed.

In the next few years from now, solar activity will come down . This will lead to increase in cloud formation&reduction in UV radiation reaching the atmosphere. Overall it will bring about a decline of 0.2 degree centigrade in Global Temperatures.

It is predicted the Carbon Emissions of 450ppm or Carbon Equivalent Emissions of 500ppm will bring a 2 degree C increase accompanied with great floods.

Carbon Dioxide is not the only greenhouse gas. Methane, Nitrous Oxide&Hydrofluorocarbons are the other greenhouse gases. When we include the effect of other green house gases then we talk in terms of Carbon Dioxide Equivalent.

STEREO (Solar Terrestrial Relations Observatory) mission to scan the SUN In 3-D:

NASA is to launch two nearly identical space-based observatories that will enable the construction of 3D view of the Sun. This is a $550-million, two year mission. This will help us understand CORONAL MASS EJECTIONS better.

NASA Scientist Madhulika Guhathakurta says,” of the bazillion stars that we have in our night sky, sun is the one that only counts. Any understanding or breakthrough we can make in understanding the sun&its environment is of direct relevance to every human being on this Planet”.

This mission will improve early warning system against CME s.

[“The Mysterious Origins of Solar Flares” George D. Holman, Scientific American, April 2006;

“The fury of Space Storm”, James L. Burch, Scientific American, April 2001;

”Paradox of Hot Sun’s Corona” Bhola N. Dwivedi&Kenneth J.Phillip, Scientific American, June 2001”.

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