Hydrological satellite gives better weather forecasts
Posted by Science Oxford on October 29, 2009 | comments
This is cool. A new satellite from the ESA will map out Earth’s soil moisture levels and will allow for better weather forecasting.
Visit this page »The first hydrological satellite, SMOS, will map out the earth’s soil moisture levels, which will enable scientists to anticipate floods earlier and to improve weather forecasts. TU Delft will be applying the data to the Volta Basin in West Africa, among other things. The European space organisation ESA is launching SMOS on Monday 2 November.
Shovel“Soil moisture levels actually form the basis for every hydrologist,” says Professor Nick van de Giesen of TU Delft. “Using them, along with other information, you can make decisions on such matters as flooding, drought, desertification and regional weather.”
“Good data on soil moisture levels, however, is scarce. Up to now, you had to go out into the field with a shovel, in a manner of speaking, in order to map out soil moisture levels. That is all going to change with the SMOS (Soil Moisture and Ocean Salinity) satellite.”
Radio wavesSMOS, which belongs to the European space organisation ESA, is the very first hydrological satellite. It measures the faint radio waves that are sent out through the upper layer of the soil and the sea water. The strength of the signal measured is an indicator of how much water there is in the soil. So for the first time, this satellite will continually be mapping out the soil moisture levels of the whole earth, even if rather roughly at present.
Atmosphere
The upper layer of the soil is the link between the earth and the atmosphere. We know that soil moisture has a great influence on regional weather and climate. New and more detailed information about this can therefore be used to improve weather forecasts. But it will also be possible, for instance, to anticipate floods earlier and to understand storm conditions better.
CablesAlong with other scientific parties, TU Delft will be responsible for calibrating the SMOS data. “To do so, we will combine the satellite information with a new type of measurement on the ground, among other things,” says Van de Giesen. “Through fibre optic cables, we will measure the temperature of the soil at several depths. This temperature is an indication of the soil moisture levels.”
Besides carrying out this calibration, TU Delft will be applying the new information to large basins, such as the Volta in West Africa and the Rhine.
OceansBesides measuring soil moisture, the SMOS satellite uses the same technique to measure the levels of salt in the oceans. Together with the temperature, salt levels determine the density of the sea water. Global differences in this density produce large-scale ocean currents, which in turn have a great influence on the earth’s climate.
What do you think?