Weather station Jena

History of the weather station at the University of Jena

from Götz Hartmann, Uni-Journal of the FSU Jena, 2002

"...the climate station in Jena owes its existence to the initiative of Duke Carl August of Weimar and his minister Goethe. They hoped for reliable weather forecasts from regular meteorological observations. Carl Dietrich von Münchow, the first director of the Jena Observatory, which had been built in 1812/13 as an annex to the Schiller House and assigned to the university, was therefore responsible for documenting weather conditions from the very beginning. However, Münchow, whose records begin in October 1813, did not always record the weather data at the same times or every day. It was not until his successor Friedrich Posselt that they were reliably noted three times a day. Between 1816 and 1825, Carl August had eight more climate stations set up in the Grand Duchy of Saxony-Weimar-Eisenach and equipped with instruments by Friedrich Körner, a university mechanic from Jena. He thus created the first state meteorological measuring network in Germany. The observers were given regulations, which Körner had drawn up together with Goethe in 1817, and had to send their records to the state minister in Weimar once a month. However, since the hope for reliable weather forecasts was not fulfilled, Goethe ordered the closure of all grand ducal climate stations in 1832, with the exception of Jena. There, meanwhile under Posselt's successor Ludwig Schrön, in addition to the meteorological data of air pressure, temperature and humidity, the temperature extremes and the amount of precipitation were also noted for each day. In addition, Schrön provided the exact time for the clock of the city church.

After Schrön's death in 1875, regular weather recordings did not take place again until Ernst Abbe was appointed director of the observatory in 1878. Abbe had a new observation hut built and reduced the six daily reading times introduced by Schrön back to three; in 1887, he fixed them to the dates of 7 a.m., 2 p.m. and 9 p.m., which are still valid today. From 1879, the snow depth was also recorded, from 1882 the visibility in fog, and since 1892 the daily duration of sunshine; finally, in 1937, the temperature on the ground was added. In 1879, an assistant was hired specifically to record the weather data. The documentation of the data has not been interrupted since then, not even during World War I, when the assistant position was vacant and the then director of the observatory, Otto Knopf, had to read the measuring instruments himself again.

Jena's weather data have been recorded at the same location since 1813. An exception is the summer of 1945, when the observatory served as a command center for the Red Army and the climate station had to move to Löbderstraße 5. In 1951, the Meteorological Service of the GDR moved the station to Wöllnitzer Straße and in 1954 back to Schillergässchen, where Helmut Kauf, who was responsible for weather observation at the observatory at that time, had continued the measurements in the meantime. There, in an immediate environment that has hardly changed since the late 19th century, they are still taken every day."

The collection of measurement data is now largely automated and the data are transmitted online directly to the German Weather Service (DWD); however, precipitation, the degree of sky coverage, and visibility are still read, assessed, and noted with a trained eye by university employee Christine Luge - as in Goethe's day.
"As far as (...) the documentation of the data is concerned, the almost 180-year-old instruction for the grand-ducal weather observer in Ilmenau has not yet lost its validity: "In the present darkness of meteorology, which despite the efforts of expert and conceited scholars has not yet been able to be cleared up at all..., it is indeed a meritorious work of the present to collect as many observations as possible, so that at least our descendants will find something to hold on to .... ."