Processing GERB Data with an Internationally Distributed System
- Paper number
IAC-08.B1.4.3
- Author
Dr. Peter M. Allan, Rutherford Appleton Laboratory, United Kingdom
- Year
2008
- Abstract
The Geostationary Earth Radiation Budget (GERB) instrument was designed to measure the total energy output of the Earth in two broad wavelength ranges, reflected sunlight and thermal emission, to an accuracy better than 1%. By understanding the balance of incoming radiation from the Sun and the outgoing radiation from the top of the Earth’s atmosphere, we can monitor the energy driving the Earth’s climate – something that is necessary in order to understand global warming. There have been several instruments that have monitored the radiation budget in the past, ERBS, ERBE, CERES. However, GERB is the first instrument to do so from a geostationary platform. This gives GERB a unique view of the Earth Radiation Budget, the primary advantage being that we get a set of data on almost half of the Earth every 15 minutes, with individual images generated in just under three minutes. The combination of high time resolution and coverage of a large fraction of the Earth means that GERB is able to monitor the diurnal cycle of the Earth with high accuracy for the first time.
The paper will describe the GERB instruments, the end-to-end flow of data through the multi-national data processing system to the science archive and some of the scientific results that are emerging from this new generation of instruments. The data processing system involves a near real-time system spread over three countries. While this may seem unnecessarily complicated, it allows maximum exploitation of existing scientific expertise and is technically little different from using a network of computers in one location. One of the challenges in designing the data processing system was how best to handle the fact that data arrive at very different rates, from a new raw data packet every 0.6 seconds to a set of monthly average data products.
Four GERB instruments have been built with the intention of providing a climate record covering 15 years. Two GERB instruments are currently in space on the Meteosat Second Generation satellites, with two more due to follow on MSG-3 and MSG-4. The fact that data are generated with high time resolution and good spatial coverage means that valuable comparisons can be made between the data from GERB and computer climate models. These show excellent agreement in many ways, but the differences also point to improvements that can be made in future models, thereby leading to better prediction of the weather and the climate.
- Abstract document
- Manuscript document
IAC-08.B1.4.3.pdf (🔒 authorized access only).
To get the manuscript, please contact IAF Secretariat.