meteorology

from Wikipedia, the free encyclopedia

Meteorology (from ancient Greek μετεωρολογία meteōrología "investigation of unearthly things" or "investigation of heavenly bodies") is the study of physical and chemical processes in the atmosphere and also includes their best-known areas of application - weather forecasting and climatology .

About the atmosphere physics, climate research , and improving methods for weather forecasting also going meteorology therefore also investigated chemical processes (eg. As ozone formation, greenhouse gas ) in the air envelope and observed atmospheric phenomena in the sky . It is counted among the geosciences and is often affiliated with the institutes for geophysics or the respective faculty for physics at universities (see Meteorology Studies) .

Weather map : high and low pressure areas over the Atlantic

History of meteorology

Origins

Weather observation was already of interest to our nomadic ancestors. Observing and recording the local weather was - and still is - an important basis for farmers to make fundamental decisions: when to sow , when to harvest.

  • The earlier you sow, the longer the possible vegetation period until harvest; however, earlier sowing also threatens losses due to the effects of weather on the young seed.
  • The later you harvest, the greater the yield. However, it may be better to bring in the harvest a little earlier, e.g. B. to bring you to safety before an approaching storm or a period of bad weather

The natural scientist and philosopher Theophrastus of Eresus also undertook meteorological observations in the 3rd century BC. Chr.

Weather observation and research can also be used for military purposes. For example, an accurate forecast of wind direction and strength was useful or even decisive for sea ​​battles .

The discovery of America was the prelude to the “conquest of the oceans”. The increasing intercontinental ship traffic brought many new insights into weather phenomena . The weather on the ships was observed in detail and recorded in the logbook .

Albertus Magnus provided early theoretical approaches : In his treatise De natura locorum , he described the dependence of the properties of a place on its geographical location . Such approaches continued to have an effect, as can be seen in a brief presentation of theoretical climatology by the Viennese astronomer Georg Tannstetter (1514).

The first revolution in meteorology began between 1880 and 1900, when the meteorological services of individual states were able to exchange their weather data using wired and wireless telegraphy, thus enabling real-time data comparison. This enabled synoptic weather maps to appear for the first time . The basis for this was the precise documentation in observation books or tables and the research into statistical correlations.

20th century

After the invention of aircraft (the first Montgolfière drove in 1783), balloons were used to better research the weather in the lower layers of the air (see also weather balloon ; main article: Chronology of Aviation ).

From the invention of powered flight in 1909, the importance of weather research increased. Airplanes became important research objects with which one could observe or photograph the weather over a large area (e.g. "clouds from above") and measure weather data.

Numerous aircraft were used in World War I; initially for clarification ; later also for dropping bombs. Aircraft technology (e.g. maximum altitude, range, speed) developed very quickly (see e.g. Air Force (German Empire) , French Air Force , Royal Air Force ).

During the Second World War, the radar developed in the 1930s was used; it enabled the acquisition of new types of weather observation data (see weather radar ).

During the Second World War, all belligerent nations massively increased their air forces (they proved to be decisive for the war on many fronts ); the first jet planes were built; large amounts of weather data were collected. Fighter planes were developed and built that could reach particularly high service heights . z. B. the German Ta 152 aircraft or the Soviet Jak-9PD reached an altitude of about 14 km; shortly before that, a maximum height of around 4 km could be reached.

The Wehrmacht maintained weather stations in the Arctic from 1941 to 1945 .

After the war the Cold War began ; many countries went to great lengths to research the weather (e.g. the US “Thunderstorm” project). In addition, reconnaissance aircraft were developed and built that could fly so high that they could not be reached by enemy ground missiles at the time. The Lockheed SR-71 spy plane has a service ceiling of 24,385 meters.

Weather research at high altitudes mainly served space travel , in particular manned space travel (see also The Space Race in the Cold War ), and the development of ICBMs . In 1957, the Soviet Union launched the first operational ICBM ; a few weeks later, it launched two satellites, Sputnik 1 and Sputnik 2, into space, triggering the “ Sputnik shock ” in the west .

The use of weather satellites was a major milestone for weather research . The first was launched in 1960; from 1960 to 1966 the USA launched a total of 10 TIROS satellites. From 1968 to 1978 they launched eight (including one false start) NIMBUS satellites . They also had infrared cameras on board. This allows you to film weather phenomena (e.g. clouds) - even at night - and quantify how much heat heated parts of the earth's surface (land masses, and to a lesser extent water surfaces) radiate into space at night (see Earth # Global Energy Balance ). The Satellite Meteorology considered a separate branch of meteorology.

Well-known weather researchers were z. B.

21st century

The rapid advances in electronic data processing ("EDP") and the rapidly growing computing power make a quantum leap in weather forecast possible . Ever larger amounts of data from more and more measuring stations are processed. The complex algorithms and models according to which they are evaluated require powerful computing systems. This makes the forecasts more precise and also more detailed in their local resolution.

General

Scale diagram of typical atmospheric forms of movement

Although the main focus of meteorology is on the large-scale dynamic processes within today 's earth's atmosphere , the model concepts developed within the framework of a better understanding of weather dynamics can also be transferred to other systems .

One therefore also counts limited room climates or urban climates , extraterrestrial atmospheres or atmospheres from past geological ages ( paleoclimatology ) to the subjects of study in meteorology. However, these usually only play a larger role in research, where they also serve in part as a "playground" for improving those models that also describe the current earth's atmosphere. Attempts are therefore being made to develop a secure database through precise observations of the earth's atmosphere and at the same time to use this data to create an ever better understanding of meteorological processes .

Many methods, approaches and ideas of dynamic meteorology arise from general fluid dynamics and find further application in oceanography , geophysics and engineering as well as in almost all environmental sciences .

Meteorology is - apart from weather observation ( meteorology ) - a young science . It has an extraordinarily interdisciplinary approach, so it combines many different sciences. Scientific subjects that are used or touched by meteorology are:

Meteorology can be subdivided into different directions, with some of them strongly overlapping.

Sub-areas
according to procedure according to spatial conditions according to the techniques used
general meteorology Aerology Satellite meteorology
theoretical meteorology Aeronomy Radar meteorology
experimental meteorology Boundary layer meteorology LIDAR meteorology
applied meteorology

 

 
 
 
 Micrometeorology
Maritime meteorology
Alpine meteorology
Glacial meteorology
Polar meteorology
Medium latitude meteorology
Tropical meteorology

This compilation is not complete. In particular, meteorology deals not only with the troposphere , i.e. the lowest layer of the atmosphere, but also with the stratosphere and, to a limited extent, even with the mesosphere and thermosphere .

Data sources and data quality

The most important task and at the same time the greatest problem of meteorology as an empirical science consists in the collection, processing and especially in the evaluation and comparison of data. In contrast to other natural sciences, in meteorology it is only possible to create controllable laboratory conditions for a small minority of questions . Meteorological data acquisition is therefore usually linked to the framework conditions given by nature, which restricts the reproducibility of measurement results and, in particular , makes it difficult to reduce to closed questions that can be answered by a measurement.

Arrangement of the weather data

The most important basic sizes are:

Many of these measured values ​​are collected in climatic gardens .

These sizes are provided in various standard formats for data exchange. In aviation, for example, the Meteorological Aviation Routine Weather Report (METAR) code is used, for the transmission of meteorological data from land stations the SYNOP FM12 / 13 code, data obtained at sea are encrypted with the ship code. Various aids can be used to classify the characteristics of a parameter; for wind, for example, the Beaufort scale or the visual mark table of a weather station can be used. Meteorological data are obtained hourly or 2 to 3 times a day (at 7 a.m. and 7 p.m. or at 7 a.m., 12 p.m. and 7 p.m.) and exchanged internationally and processed nationally, depending on the current status of a weather station in the measuring network (as a climate station, precipitation measuring station or synoptic station) . The data are processed by a plurality of meteorological measurement devices detected , the following list only lists the most important examples of this diversity:

Weather map with station data

The multitude of measuring devices, the nature of the measurands, and the objectives of their use give rise to numerous problems.

For the measured variable precipitation, for example, various measuring devices for recording rain, dew, snow and hail are widely used and tried and tested. For methodological reasons, a distinction is made between liquid ( rain , dew ) and solid ( snow , hail ) precipitation and the measured variable is therefore classified according to the types of precipitation recorded. The measurement accuracy of the methods commonly used on the market for determining the liquid precipitate can be set at approx. 30%, that of the solid precipitate is no better. Other hydrometeors are captured by sucking in a quantity of air or by depositing it on rods and are determined volumetrically.

The quality of the precipitation measurements is primarily influenced by the parameters wind, air temperature, installation altitude above ground, evaporation and installation location. The question of their comparability or the necessary corrections is the subject of scientific discussions; Numerous comparisons have already been carried out for a wide variety of precipitation gauges (see WMO or CIMO ).

The measurement of the other meteorological variables also has similar, albeit minor, problems: for example, the vertical component of the wind speed could not be recorded correctly for a long time and even today the measurement of vertical gradients is very complex. It is therefore mostly limited to ground measurements, whereby standardized ground distances of usually two or ten meters are used depending on the measured variable. It should be noted here that a single meteorological measurement is almost meaningless and the weather dynamics in larger spatial scales can only be understood and forecasted by a large number of measurements. These measurements must this be comparable, which is why the standardization and standardization of measuring instruments and measurement techniques in meteorology is very important, but can be implemented only partially due to many practical problems. We therefore also speak of measuring networks and the establishment of weather stations . These usually follow VDI guideline 3786 or other guidelines , some of which are standardized worldwide by the World Meteorological Organization .

In addition to the spatial comparability of the data, which is necessary for weather forecasting, there is also a temporal comparability, which among other things plays a decisive role for climate forecasts. If the development of the measuring devices and thus the measuring accuracy is not taken into account when analyzing very old data, then this data is scientifically almost worthless, which is why measuring devices that are often outdated and have not changed for decades are still very widespread worldwide. This is also a question of costs, because it does not always make sense to use the most modern and therefore most expensive measuring devices, as these are only affordable for individual countries or institutes. In addition, every change in measuring equipment is linked to a change in data quality , which can easily lead to incorrectly postulated or interpreted trends in longer and very valuable measurement series from many decades to a few centuries . A higher level of accuracy is therefore often foregone in favor of comparability . In the case of global warming of a few degrees Celsius , these very old data are usually of little help, since their measurement errors usually exceed the effect of these possible temperature changes. A large part of the arguments of so-called “ climate skeptics ” is based on this partially controversial data situation, but there are also other natural climate archives with much more precise data over very long periods of time. With the discussion about the informative value of temperature records, u. a. the BEST project at Berkeley University .

There is therefore a need to critically scrutinize measurement data and to classify it correctly due to location-specific, personnel and metrological factors. In meteorology, spatial data analysis is in the foreground, in the otherwise closely related climatology, on the other hand, temporal data analysis ( time series analysis ) plays the main role.

Radiation measurement

Obtaining physical quantities from measurements in different areas of the electromagnetic spectrum is a challenge that can only be achieved with great technical effort and through the use of models .

Satellite measurement

Nowadays satellites , especially weather and environmental satellites , are an important tool for meteorologists, especially satellite meteorology . A distinction is made here between geostationary satellites , which are stationarily anchored at an altitude of 36,000 km above the earth, and satellites which orbit the earth on a LEO within 400 to 800 km. Due to the large-scale recording of measurement data, global relationships can be recorded and thus ultimately understood with satellites.

Nowadays, only by means of satellites is it possible to obtain information about the atmosphere in the form of observations on a global basis and resolved daily. In particular, the condition and composition of the upper atmosphere (stratosphere, mesosphere, thermosphere) can only be examined effectively through the use of satellites.

A high spatial and temporal resolution of satellite data is desirable, since it enables one to effectively monitor atmospheric constituents and their changes. Satellite data provide valuable services, for example, in monitoring the development of the ozone holes, as satellite measurements can be used to estimate the ozone content per altitude and per day very precisely. Many other atmospheric trace gases are monitored in this way (e.g. methane , carbon dioxide , water vapor ), but pressure and temperature in the atmosphere can also be determined very precisely and spatially exactly. The ongoing development of instruments and the trend towards small, highly specialized satellites also make it possible to track anthropogenically induced disturbances in the composition of the atmosphere. Together with measurements carried out in situ (for example by balloon) and model calculations, this gradually results in an ever more complete picture of the state of the earth's atmosphere.

Tropospheric satellite data are used to obtain information about regions that cannot be accessed by any other measurement method. An example are precipitation estimates or wind speed determinations over the oceans . There is no close measuring network available and for a long time they had to rely on large-scale data extrapolation , which even today means that significantly lower forecasting quality can be achieved in strongly maritime weather conditions, for example on the west coast of North America , than in continental weather conditions. All non-satellite-based data surveys on the ocean come from ship or buoy measurements or from measuring stations on isolated islands . Knowledge of the weather conditions over the oceans can therefore lead to an improvement in the overall forecast of precipitation events on coasts . This is vital information , especially for countries affected by the monsoon , such as India .

Satellite data are used, for example via so-called data assimilation, as a basis in climatology to improve or support their models and to enable comprehensive and uniform data acquisition .

Working with satellite data requires extensive knowledge of data processing and the associated technology and techniques (e.g. efficient programming). Large amounts of data (now in the range of terabytes) have to be received, forwarded, stored, processed and archived.

Models and simulations

Models play an outstanding role, particularly in climatology ( climate model ), but also in meteorology ( numerical weather forecast ) and remote sensing . They gain their importance through various factors:

  • With the increasing development of measurement technology and the increasing demand for weather forecasts, the amount of data also increases enormously. As a result, a written evaluation of the data on weather maps is no longer sufficient. Simplified models and computer simulations are therefore faster, more cost-effective and only enable extensive data evaluation.
  • The periods in which many effects, such as sea ​​level fluctuations , occur are extremely long and can only be simulated with models. They cannot be observed directly and there are also no continuous and qualitatively sufficient series of measurements for such periods. Meteorologists therefore generally do not have a laboratory in which they can carry out measurements and are therefore dependent on theoretical models. These then in turn have to be compared with actually observed effects. Exceptions include the climatic chamber AIDA the Forschungszentrum Karlsruhe and the air chamber at the Research Center Jülich .

The design of models is just as much a challenge as their content. Only models that describe nature as adequately as possible can be used meaningfully in research and practice. Since such models can easily occupy entire data centers due to the complexity of the modeled system, efficient algorithms , i.e. statistical assumptions that simplify nature , are an important point in the development of the models. Only in this way can computing time and thus costs be kept manageable.

In the 1920s, the mathematician Lewis Fry Richardson developed methods with the help of which the enormous complexity of mathematical meteorological models could be approached. These are still often the basis of meteorological simulations ( simulation model ) on supercomputers . It is therefore not without reason that in many cases these are used to simulate the weather or climate dynamics, whereby these reach their limits quickly, despite their sometimes gigantic dimensions.

Different types of atmosphere models can be roughly differentiated: radiation transfer models ( e.g. KOPRA), chemical transport models ( e.g. ECHAM ) and dynamic models. The trend, however, is towards integrated models or “world models” that trace all of nature (SIBERIA 2).

When improving the quality of the models, as everywhere in physical modeling, statistical procedures as well as experimental observations, new ideas, etc. flow into the process. A well-known example of this is the development that has led to the realization that changing the amount of trace gas in the atmosphere (e.g. carbon dioxide or ozone ) can lead to an “unhealthy” heat development in the biosphere (e.g. greenhouse effect , cooling of the stratosphere ). The discovery of the ozone hole and the increasing attention of scientists to the associated atmospheric chemistry also fall into this category.

The simplest meteorological model and at the same time the first test for all newly developed models for weather forecasting is the simple transfer of the current weather to the future. The simple principle of constant weather applies here, i.e. it is assumed that the weather of the next day will correspond to that of the current day. This is called the persistence forecast. Since weather conditions are often almost constant for a long time, this simple assumption already has a probability of success of around 60%.

Weather data

The exchange of weather information (current, historical, forecasted) to simplify, has the World Meteorological Organization (WMO) , the data format GRIB , English. GRI dded B inary, defined.

The legal situation is extremely complex (as is the case with geospatial information ). Above all, copyright and in particular database protection law, which relates to collections of weather data (see database work ), are relevant . However, there are also European guidelines for the further use of public sector data ( Public Sector Information , implemented in Germany as the Information Further Usage Act ) and for the dissemination of environmental information (implemented in Germany as the Environmental Information Act ), which affect the rights to weather data and its dissemination.

Authorities, associations, companies

Lessons from the on-board meteorologist on the Gorch Fock (1968)

Germany

Austria

Switzerland

United States

United Kingdom

Denmark

France

Norway

Sweden

Europe

International

Lists

See also

Portal: Weather and Climate  - Overview of Wikipedia content on the subject of weather and climate

literature

In German language

Textbooks
  • Stefan Emeis: Meteorology in brief. Hirt's key words . Borntraeger, Stuttgart 2000, ISBN 3-443-03108-0 .
  • Hans Häckel: Meteorology (= UTB. Geosciences, Agricultural Sciences 1338). 8th edition. Ulmer, Stuttgart 2016, ISBN 978-3-8252-4603-7 .
  • Peter Hupfer, Wilhelm Kuttler: Weather and Climate - An Introduction to Meteorology and Climatology . 12th edition. Teubner, Leipzig 2006, ISBN 3-8351-0096-3 .
  • Brigitte Klose: Meteorology. An interdisciplinary introduction to the physics of the atmosphere . Springer-Verlag, 2008, ISBN 978-3-540-71308-1 ( limited preview in the Google book search).
  • Wilhelm Kuttler, Ewald Zmarsly, Hermann Pethe: Basic meteorological-climatological knowledge. An introduction with exercises, tasks and solutions . Ulmer Verlag, Stuttgart 2002, ISBN 3-8252-2281-0 .
  • Wilhelm Lauer, Jörg Bendix: climatology . 2nd Edition. Westermann, Braunschweig 2006, ISBN 3-14-160284-0 .
  • Horst Malberg: Meteorology and Climatology - An Introduction . 2nd Edition. Springer, Berlin 2002, ISBN 3-540-42919-0 .
  • Wolfgang Weischet: Introduction to general climatology: physical and meteorological basics . 6th edition. Borntraeger, Berlin 2002, ISBN 3-443-07123-6 .
Non-fiction
Essays

In foreign languages

  • Roger G. Barry, Richard J. Chorley: Atmosphere, Weather and Climate . 8th edition. Routledge, London 2003, ISBN 0-415-27170-3 .
  • Harald Frater: Weather and Climate . Springer, Berlin 1999, ISBN 3-540-14667-9 .
  • Anton Wilhelm Goldbrunner: Meteorología . Servicio Meteorológico de las Fuerzas Armadas, Maracay Venezuela 1958.
  • James R. Holton : Encyclopedia of Atmospheric Sciences . Academic Press, San Diego / London 2002, ISBN 0-12-227090-8 .
  • Vincent J. Schaefer, John A. Day: Atmosphere. Clouds, rain, snow, storms. Peterson Field Guides. Houghton Mifflin Company, Boston / New York 1981, 1991, Easton Press, Norwalk Conn 1985. ISBN 0-395-90663-6

Web links

Commons : Meteorology  - collection of images, videos and audio files
Wikisource: Meteorology  - Sources and full texts
Wiktionary: Meteorology  - explanations of meanings, word origins, synonyms, translations
Data and images

Individual evidence

  1. ^ Wilhelm Gemoll : Greek-German school and hand dictionary . 9th edition. Oldenbourg, Munich 1991, ISBN 978-3-486-13401-8 .
  2. ↑ Duden Online Dictionary: Meteorology. Retrieved September 5, 2015 .
  3. ↑ H.-D. Bruß, D. Sählbrandt: Meyer's pocket dictionary "Earth's atmosphere" . 1 publisher = VEB Bibliographisches Institut edition. Leipzig 1965.
  4. ↑ Ewald Wagner, Peter Steinmetz : The Syrian excerpt from the meteorology of Theophrast (= treatises of the humanities and social science class of the Academy of Sciences and Literature in Mainz. Born 1964, No. 1).
  5. ^ Siegmund Günther : History of geography . Leipzig, Vienna 1904, p. 116f.
  6. ↑ SZ of September 24, 2015 A supercomputer for the weather - accessed on April 12, 2016
  7. ↑ DWD Research Composite Creation - accessed on April 12, 2016
  8. ↑ news.at of September 17, 2007 Quantum leap for weather forecasting: New supercomputer ten times faster - accessed on April 12, 2016
  9. ^ Heinz Fortak: Meteorology . 2nd Edition. Reimer, 1982, ISBN 978-3-496-00506-3 .
  10. ↑ Process = directed sequence of events. A distinction is made between deterministic and stochastic processes