Bruno Lüth: The winner of the local ''Jugend forscht'' competition concerning the science of geography and geospatial science briefly presents his results for you. 

 Are there thunderstorm centers in the region of Goettingen?
In late august of 2007 heavy thunderstorms  with  devastating consequences occured in certain parts of our county (Goettingen).
Zum Vergrößern bitte anklicken It had also been noticeable, that some of our region's districts were more present in the media than others ,due to damages caused by storm.

Therefore I decided to contemplate our regions thunderstorm  frequency. Furthermore I checked if there are  increased numbers of thunderstorms in certain areas around Goettingen.  

For that I analysed lightning data, which was provided by the  "Blitzinformationsdienst"(lightning information service) of the company  Siemens (BLIDS). The data I used for my research  was taken from the BLIDS database.



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A Window with the vertices 9° 57' 36,828" E 51° 42' 21,024" N and 10° 10' 47,604" E 51° 20' 46,176"N (geografic altitude and longitude) was used. The documented strikes happened from the 1st of January 1998 to the 31st of December 2004; the information takes place in a span of seven years.

The calculated accuracy of the measurements can differ by 300meters. The locating efficiancy is at about 94-99 per cent.

the lightning is captured due to an electromagnetic field, accuring when the lighting discharges.

 

The collected information consists of 20254lightings, 16107 of those are lightings between cloud and ground and 4147 only between the clouds. But  for the evaluation only the ground lighting qualifies, since the location of the cloud lightning is not as accurate enough.

The evaluation window(vertices: 9.96023°E 51.70584°N and 10.17989°E 51.34616°N) averages 40km by 40km. This sector was divided into 400equally sized sections, so each one 2km by 2km.

 

 

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Deveoped with Micosoft Excel, the lightnings were arranged in this 20 by 20 raster. Which means that they were sorted, first by geografical amplitude then longtitude in each twenty files. 

In statistical appliance 42 had to been messured in each of the fourhundred sectors. 

While counting the single units it is to notice that the messured amound  greatly differs from the average value.

Checking the location with a higher felling rate it is to notice, that the lightning usually discharges above of locations with a high population or at least close to these. Especially west and south of Goettingen the lightnings strike. Furthermore around Adelebsen, Friedland and Gieboldehausen, which is north of the lower Eichsfeld. 



The elevation does not seem to be of great relevance. Since, for example around Goettingen as many fellings occour as around Adelebsen, which is higher around sea level than Goettingen. Also in the forest of Goettingen, which partially lies over 350meters over sea level fellings occour less then around the city center(150meters over sea level).
The relief power does not seem to be of great importance. However the altitude differences do not variate as much as in high mountains for example.

The relief shape, on the other hand, seems to play a greater role. If the settlement lies in a valley(like Goettingen) so that the high winds are blocked by the high mountain passages the thermal(thundercloud) can heat up over the settlement less affected then over a free highpass (e.g.Dransfeld) .

The cause for higher felling rate over highly populated location could be caused by a acid in kondensation in the air, which is more in highly populated locations.

The last statement needs to be proved by an other prject of "jugend forscht" for it is not stateable without provment.