METEOROLOGICAL STUDIES

Andrija Mohorovičić gained his international fame by his work in seismology. It is not so well known that the beginning of his scientific work was in meteorology. Everything started in 1882, when Mohorovičić came to the Nautical School in Bakar…

In Bakar...

As a teacher who taught mathematics, physics and meteorology Mohorovičić came into direct contact with atmospheric processes. This stimulated his interest in the problems of this science. Soon after his arrival in the Nautical School he tried to establish a meteorological station in Bakar.  In Mohorovičić's words:

»Soon after the re-organization of the Nautical School the idea arose of establishing a meteorological station within the School: first, because of the subject-matter itself; secondly, because this is a subject of very great importance for the students – future seamen, and is being taught as a separate course at the School; thirdly, because of the orographic position of Bakar.«

He succeeded in this effort in 1887.  Mohorovičić described the station and its instruments in the sixth curriculum program of the Nautical School in Bakar. Along with regular observation instruments needed on some meteorological stations, such as barometer (air pressure), thermometer (temperature), psychrometer (humidity), ombrometer (precipitation) and heliograph (solar radiation), Mohorovičić’s interest primarily involved the movement of the clouds. He constructed the instrument himself – the nephoscope – which enabled him to determine the speed and direction of cloud movement.

His diligent and detailed observations, especially of the clouds, resulted with several published international and domestic scientific papers. So, for instance, he described stationary cumulus clouds that appear at mountain peaks during bura  - the well known “cap” and enclosed the drawing (6).

In Zagreb...

In 1891. Mohorovičić was transferred to the science grammar school in Zagreb. Soon he took over the administration of the meteorological observatory from Ivan Stožir who had carried out meteorological observations in Zagreb continuously for 30 years. Mohorovičić successfully continued the guidance of the observatory. He endeavoured to improve both qualitatively and quantitatively the existing network of meteorological stations. This also included equipping the observatory in Zagreb with the necessary instruments. Gradually, he expanded the activities of the observatory to other fields of geophysics: seismology, geomagnetism and gravity. He was also involved in scientific work. He published papers about extraordinary meteorological phenomena like the tornado near Novska (10, 11), and the whirlwind near Čazma (15).

However, his studies based on the observations of the clouds, that he published as a teacher in Bakar lead him to his doctorate dissertation in 1893.

He was involved in scientific and professional work in meteorology until the turn of the century. He published papers about thunderstorms (12) and hail suppression (17), about the decrease of temperature with height (16), he described the climate of Zagreb (13), gave instructions for the observers of precipitation (19). It is less known that he published the first public weather forecasts in daily newspapers (14). I. Lisac wrote about that:

»The year 1893 can be considered as the beginning of the idea of publishing weather forecasts in Zagreb, according to the letter No. 12 from January 16, 1918 (from the Geophysical institute archives) that A. Mohorovičić sent to the government. In the letter Mohorovičić asked for help in restoring the work on weather forecasts after the end of the World War I. In this letter Mohorovičić wrote: “ … The author of this letter started to publish weather forecasts upon the request of the local daily news in the year 1983...«

BIBLIOGRAPHY OF THE ANDRIJA MOHOROVIČIĆ'S METEOROLOGICAL  PAPERS:

1) A. Mohorovičić, 1888: Wolkenmessung, Meteorologische Zeitschrift 23, 326-327.

2) A. Mohorovičić, 1888: Meteorologijska opažanja na kr. nautičkoj školi u Bakru godine 1887. s kratkim predgovorom, VI. program kralj. nautičke škole u Bakru koncem školske godine 1887./88., 3-41.

3) A. Mohorovičić, 1889: Nekoliko opažanja o vertikalnoj komponenti gibanja oblaka, Rad JAZU 95, 202-216.

4) A. Mohorovičić, 1889: Interessante Wolkenbildung über der Bucht von Buccari, Meteorologische Zeitschrift 24, 56-58.

5) A. Mohorovičić, 1889: Wolkenbeobachtungen in Buccari, Meteorologische Zeitschrift 24, 190-192.

6) A. Mohorovičić, 1891: Nekoji rezultati opažanja oblaka na kraljevskoj nautičkoj školi u Bakru – Na temelju opažanja A. Mohorovičića i A. M. Zuvičića, Rad JAZU 104, 1-86.

7) A. Mohorovičić, 1891: Täglicher Gang der Bewölkung zu Buccari, Meteorologische Zeitschrift 26, 189.

8) A. Mohorovičić, 1892: Die tägliche Periode der Bewölkung zu Buccari, Meteorologische Zeitschrift 27, 76-77.

9) A. Mohorovičić, 1892: Dnevna i godišnja perioda oblaka u Bakru – Na temelju opažanja A. Mohorovičića i A. M. Zuvičića, Rad JAZU 111, 34-50.

10) A. Mohorovičić, 1892: Windhose bei Novska (Slavonien), Meteorologische Zeitschrift 27, 320.

11) A. Mohorovičić, 1893: Tornado kod Novske, Rad JAZU 117, 1-19.

12) A. Mohorovičić, 1895: Osobito djelovanje groma, Nastavni vjesnik 3, 105-106.

13) A. Mohorovičić, 1897: Klima grada Zagreba, Rad JAZU 131, 72-111.

14) A. Mohorovičić, 1897: Unsere Wetterprognosen, Agramer Zeitung 72/41, 1-2.

15) A. Mohorovičić, 1898: Vijor kod Čazme, Rad JAZU 135, 51-56.

16) A. Mohorovičić, 1901: Mjera umanjivanja temperature visinom, Glasnik Hrvatskog naravoslovnog društva 12/4-6, 98-107.

17) A. Mohorovičić, 1901: Pucanje sa tučobranima na pokušalištu hrv.-slav. gospodarskog družtva u Zagrebu, Gospodarski list 49/9, 68-69.

18) A. Mohorovičić, 1902: Uvod, Meteorološke postaje u Hrvatskoj i Slavoniji od god. 1853., Godišnje izvješće Zagrebačkog meteorološkog opservatorija za godinu 1901., III-XIX.

19) A. Mohorovičić, 1907: Naputak za motritelje oborina u Hrvatskoj i Slavoniji, Uprava meteorološkog opservatorija, Zagreb, 19 pp.

References:

Lisac, I., 1998: Andrija Mohorovičić i prognoza vremena, Znanstveni skup “Andrija Mohorovičić” – 140. obljetnica rođenja, Zagreb, 77-91.
Orlić, M., 1998: Znanstveni radovi Andrije Mohorovičića i nekih hrvatskih geofizičara poslije njega, Znanstveni skup “Andrija Mohorovičić” – 140. obljetnica rođenja, Zagreb, 61-75.

Skoko, D., J. Mokrović, 1998: Andrija Mohorovičić, Državni hidrometeorološki zavod i Školska knjiga, Zagreb, 111 pp.