Weather station
From Wikipedia, the free encyclopedia
A weather station is a facility with instruments and equipment to make observations of atmospheric conditions in order to provide information to make weather forecasts and to study the weather and climate. The measurements taken include temperature, barometric pressure, humidity, wind speed, wind direction, and precipitation amounts. Wind measurements are taken as free of other obstructions as possible, while temperature and humidity measurements are kept free from direct solar radiation, or insolation. Manual observations are taken at least once daily, while automated observations are taken at least once an hour.
Contents |
[edit] Instruments
Typical weather stations have the following instruments:
- Thermometer for measuring temperature
- Barometer for measuring barometric pressure/air pressure
- Hygrometer for measuring humidity
- Anemometer for measuring wind speed
- Wind vane for measuring wind direction
- Rain gauge for measuring precipitation
[edit] Exposure
Except for those instruments requiring direct exposure to the elements (anemometer, rain gauge), the instruments should be sheltered in a vented box, usually a Stevenson screen, to keep direct sunlight off the thermometer and wind off the hygrometer. The instrumentation may be specialized to allow for periodic recording otherwise significant manual labour is required for record keeping. Automatic transmission of data, in a format such as METAR, is also desirable as many weather station's data is required for weather forecasting.
[edit] Daily observation times
Historically readings were taken by weather observers who were typically not paid and performed the duty as part of their permanent jobs (e.g., postmaster). These weather readings were taken between 7 and 9 a.m. local time daily as unpaid observers were unwilling to take readings from midnight to midnight. Since the advent of automatic weather stations, such as automated airport weather stations and personal weather stations, surface weather observations are taken on an hourly (or more frequent) basis.
[edit] Networks
A variety of weather station networks have been set up globally. Some of these are basic to analyzing weather fronts and pressure systems, such as the synoptic observation network, while others are more regional in nature.
[edit] United States
- The Pacific Northwest Cooperative Agricultural Weather Network[1]
[edit] See also
[edit] References
[edit] External links
- International Weather Watchers Observer Handbook (PDF 768KB 45 pages)
- Association of American Weather Observers
- Citizen Weather Observer Program
- CWOP Weather Station Siting, Performance, and Data Quality Guide (PDF 800KB 88 pages)
- WeatherBug Network Observers
- Initial Guidance to Obtain Representative Meteorological Observations at Urban Sites, by Tim R. Oke (PDF 423KB 51 pages)
- NWS Cooperative Observer Program
- NWS Observing Handbook No. 2: Cooperative Station Observations (PDF 1.4MB 94 pages)
