Weather observations by satellites and radars provide good resolutions in both time and space and are also available for areas of which there are few other observations, such as at sea. Satellite and radar data are of special importance when monitoring weather progress and severe storms. Remote sensing is also important as input in weather forecast models.
The SMHI remote sensing team studies the Earth atmosphere by satellite and radar data. A part of the research is applied towards operational meteorology and hydrology. In this group the remote sensing research stands mainly on two feet and these are the satellite part and the radar part.
Existing and new methods are developed, as well as models for analysis of cloudiness based on satellite information. Research is also carried out in climatology where long time series are used in creation of databases based on cloudiness. A significant part of the activity takes place within the international weather satellite cooperation Satellite Application Facilities (SAFs). This is done on behalf of the European weather satellite organization EUMETSAT.
The word radar is an acronym for: Radio Detection and Ranging. It is thus by radar and radar radio waves that objects can be detected remotely and distance calculations can be done. Radars operate at different frequencies, depending on the objects to be detected. In studies and research of precipitation weather radars at C-band or 5:35 GHz are used.
The network of radars in Sweden consists of 12 radars, of which 5 belong to SMHI and 7 to the Swedish Armed Forces. These cover virtually the entire country and the nearest waters along the coastline. The information from radars is used operationally by forecast meteorologists but also in the mesoscale weather analysis tool MESAN. Radar data is also used as input in numerical weather models and hydrological models.
Solar radiation - the STRÅNG project
Together with the Swedish Radiation Protection Authority (SSI) and the Swedish Environmental Protection Agency, SMHI has developed a model of solar radiation. The model is called STRÅNG and is a mesoscale model for estimation of various solar radiation parameters. The model is estimated over an area covering North Western Europe and calculations are run every day.