A measurement tower or measurement mast, also known as meteorological tower or meteorological mast (met tower or met mast), is a free standing tower or a removed mast, which carries measuring instruments with meteorological instruments, such as thermometers and instruments to measure wind speed. Measurement towers are an essential component of rocket launching sites, since one must know exact wind conditions for an execution of a rocket launch. Met masts are crucial in the development of wind farms, as precise knowledge of the wind speed is necessary to know how much energy will be produced, and whether the turbines will survive on the site. Measurement towers are also used in other contexts, for instance near nuclear power stations, and by ASOS stations.
| Structure | City or region | Country | Height (metres) | Year built | Notes | |
|---|---|---|---|---|---|---|
| Vila de Balbina | 325 | 2015 | [1] | |||
| Beijing | 325 | 1979 | for meteorological measurements, studies of air pollution and studies of the atmospheric boundary layer | |||
| Obninsk | 310 | 1958 | for meteorological and radioactivity measurements | |||
| Zotino | 302 | for measurements of meteorological variables and of concentration of greenhouse gases and aerosols | ||||
| Cabauw | 213 | 1972 | for meteorological research | |||
| Jaslovské Bohunice Meteorological Tower | Jaslovské Bohunice | 212 | 1986 | [2] | ||
| Karlsruhe | 200 | 1972 | ||||
| Rödeser Berg Meteorological Mast | Wolfshagen | 200 | 2011 | |||
| KFU-Tower Gundremmingen | Gundremmingen | 174 | 1978 | |||
| KFU-Mast Grafenrheinfeld | Grafenrheinfeld | 164 | 1978 | for the measurement of meteorological parameters and environmental radioactivity | ||
| Mast of Richard Assmann Observatory | Falkenberg | 99 | 1998 | |||
| Obrigheim | dismantled | |||||
| 62 | 2010 | |||||
| Košetice Meteorological Tower | 250 | 2012 | [3] | |||
| 117 | transmission tower equipped with instruments for the measurement of meteorological parameters and carbon dioxide concentration | |||||
| Norunda tower | 103 | [4] | ||||
| 75 | 1963 | |||||
| NAVO-Toren | 243 | [5] |
Before developers construct a wind farm, they first measure the wind resource on a prospective site by erecting temporary measurement towers. Typically these mount anemometers at a range of heights up to the hub height of the proposed wind turbines, and log the wind speed data at frequent intervals (e.g. every ten minutes)[6] for at least one year and preferably two or more. The data allow the developer to determine if the site is economically viable for a wind farm, and to choose wind turbines optimized for the local wind speed distribution.