Beziehungen zwischen solarer Aktivität, gekennzeichnet durch Forbush-Effekte, und Eintreffgenauigkeit von Wettervorhersagen

Abstract

SummaryIn previous publications it could be shown that the significant decrease in number of thermal neutrons (Forbush effect) measured in the lower stratosphere and troposphere is not only a good indicator of temporarily increased solar activity (mostly solar flares) but is suited also to signalize changes in the large-scale meteorological situation in the lower stratosphere and troposphere. Recently it was therefore investigated, based on several years' data material, whether and in how far there may be a significant relation between onset of the Forbush effect and verification rate of weather forecasts in England, Scotland, and the Federal Republic of Germany. Immediately after solar flares we observed a considerable decrease in the frequency of very good weather forecasts or, respectively, a clear increase in the wrong prognoses when considering the region along the Atlantic coast of England/Scotland. This correlation is on the average still significant for all British weather bureaus. In Germany, however, no relationship can be established between beginning solar activity and the quality of weather forecasts. This means, that solar events cause mainly in the eastern Atlantic area acute changes in the meteorological structure in the troposphere (form and number of Rossby waves, cyclogenesis) which cannot be recognized early enough to be considered in the elaboration of the daily weather forecasts. This problem seems no longer to exist in the Central European continental area. Zusammenfassung