The Next Generation of Satellites

One focus of research at COAS, through the Cooperative Institute for Oceanographic Satellite Studies (CIOSS), is to evaluate plans for satellite systems and models. Project scientists talk to people who will use the data and come to understand the qualities the data must have such as accuracy, resolution and coverage.

In February 2005, CIOSS held a Workshop on Ocean Winds in Miami to better understand the needs of marine and hurricane forecasters. While COAS researchers have a good understanding of how oceanographers and meteorologists use satellite data, operational people have a different set of constraints and a different set of objectives.

CIOSS researchers generate the science requirements for a future system. Mike Freilich also gets into the details of designing the instruments. He works with engineers who want to know, for example, if researchers can use the data from a particular radar instrument with their algorithms to get good geophysical measurements.

Future NOAA instruments that measure ocean vector winds (speed and direction) will use a new technology called passive polarimetric radiometry. This radiometer measures the amount of upwelling radiation from the ocean–atmosphere system at a variety of microwave frequencies and polarizations.

Multiple measurements are taken from the same place and time, but at different frequencies, each of which is sensitive to each one of the geophysical effects but to different extents. Algorithms can be used to solve simultaneously for the wind speed, the wind direction, the amount of integrated liquid water in the atmosphere, the amount of integrated water vapor in the atmosphere, rain if it exists and sea surface temperature.

Freilich is validating the measurements from an existing data set of passive polarimetric radiometry (the first of its kind), so that scientists can understand the accuracy and capabilities of the new measurement.

• Michael Freilich is now serving as Director of the Earth Science Division at NASA. See his June 2007 report to Congress about societal benefits of satellite technology and future missions being planned (pdf).
  
  
• CIOSS (Cooperative Institute for Oceanographic Satellite Studies)

The QuickSCAT satellite launched on June 19, 1999, on a three-year mission and is still operating. Mike Freilich worked on QuickSCAT and is now helping generate science requirements for the future systems.