Vilho Väisälä (; September 28, 1889 – August 12, 1969) was a Finnish
meteorologist
A meteorologist is a scientist who studies and works in the field of meteorology aiming to understand or predict Earth's atmosphere of Earth, atmospheric phenomena including the weather. Those who study meteorological phenomena are meteorologists ...
and
physicist
A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate cau ...
, and founder of
Vaisala Oyj.
After graduation in mathematics in 1912, Väisälä worked for the
Finnish Meteorological Institute in ''aerological measurements'', specializing in the research of the higher
troposphere
The troposphere is the lowest layer of the atmosphere of Earth. It contains 80% of the total mass of the Atmosphere, planetary atmosphere and 99% of the total mass of water vapor and aerosols, and is where most weather phenomena occur. From the ...
. At the time the measurements were conducted by attaching a
thermograph to a kite.
In 1917 he published his dissertation in mathematics ''Ensimmäisen lajin elliptisen integralin käänteisfunktion yksikäsitteisyys'' (The single-valuedness of the inverse function of the elliptic integral of the first kind). His dissertation was the first and still is the only mathematical doctoral thesis written in the Finnish language.
[Lehto, Olli: Oman tien kulkijat. Helsinki: Otava, 2004. . Page 101]
Väisälä participated in development of
radiosonde, a device attached to a balloon and launched to measure air in the higher atmosphere. In 1936 he started his
own company, manufacturing radiosondes and — later — other meteorological instruments.
In 1948 Väisälä was nominated a Professor of Meteorology in the
University of Helsinki.
Vilho Väisälä's two brothers,
Kalle Väisälä and
Yrjö Väisälä, also made successful careers in science.
Vilho Väisälä knew
Esperanto
Esperanto (, ) is the world's most widely spoken Constructed language, constructed international auxiliary language. Created by L. L. Zamenhof in 1887 to be 'the International Language' (), it is intended to be a universal second language for ...
, and played an active role in the
Esperanto movement. During the
World Congress of Esperanto of 1969, which was held in
Helsinki
Helsinki () is the Capital city, capital and most populous List of cities and towns in Finland, city in Finland. It is on the shore of the Gulf of Finland and is the seat of southern Finland's Uusimaa region. About people live in the municipali ...
shortly before his death, he served as the rector of the so-called ''Internacia Kongresa Universitato'' ("International Congressual University"), and coordinated the specialistic lectures in Esperanto given by various academicians to the congressists.
File:Väisälä brothers childhood home (elliptic cut).jpg, An early 20th century wooden house in Joensuu at the corner of Sepänkatu and Papinkatu streets. The building was Väisälä brothers' home in 1904–19.
File:Väisälä lapsuuskoti muistolaatta.jpg, A commemorative plaque attached to the building in 1976. The text reads: "At this place was Väisälä scientist brothers, Vilho, Yrjö and Kalle's, home in 1904–1919. Joensuu Lyceum ex-students".
See also
*
Brunt–Väisälä frequency
References
External links
*
{{DEFAULTSORT:Vaisala, Vilho
Finnish meteorologists
20th-century Finnish physicists
Academic staff of the University of Helsinki
Finnish Esperantists
1889 births
1969 deaths