Measuring salinity from space, sea and soil moisture

Spain lead for the first time a research project of the European Space Agency, developed by the CSIC and the Polytechnic University of Catalonia, from space to measure the salinity of sea and soil moisture, and improving knowledge on climate change .

The announcement of this project, called SMOS, has coincided with the launch of SMOS Barcelona Expert Centre, who will be dealing with process data from the mission and coordinate the scientific activity of the fifty participating Spanish.

The space mission, with a budget of 200 million euros, of which Spain contributed 70, aims to collect data to predict phenomena like El Niño, whose appearance depends on the salinity of the water, and study the relationship between moisture Land and sea salt level in the desertification and the greenhouse effect, as explained Francesco Torres and Jordi Font, responsible for the project.

The El Nico phenomenon, which is the main cause of climate change on our planet, and occurs with a frequency variable from 3 to 6 years, is the change in the location of the centers of high and low pressure between areas of the Pacific Ocean , causing an increase in water temperature in southern 2 to 8 degrees.

The measurements were made using a microwave interferometer radiometer, which is a pioneer in this type of study, developed the UPC, which is based on a scanning system of land through 73 antennas that collect data simultaneously.

For salinity measure the electrical conductivity of water and its temperature, which gives the level of salinity. In addition, measurements must be made in every sea with buoys, using the conventional system, to confirm that the data are accurate and the space system is faithful.

The radiometer called MIRAS, and operating at 1.4 GHz (gigahertz), a low frequency band that enables the best spatial resolution, will orbit about 750 kilometers from the earth at a satellite launched in July 2008 a Russian rocket into space.

Font Torres explained that moisture and salinity are measured with sensors connected to the 73 dual-polarized antennas, placed in a folding structure of three Y-shaped arms, which will open upon reaching orbit and serve as a antenna.

According to these scientists, if no unexpected problems arise, from six months to begin to research data, and an estimated life of the satellite will be about five years.