Reporter Wang Liang of China Meteorological News
Recently, the research project of the non-profit industry (meteorology) undertaken by the National Satellite Meteorological Center-"Research on Key Technologies for Processing and Application of Fengyun-3 Morning and Dark Satellite Data" passed inspection in Beijing. After more than 1,000 day and night technical breakthroughs, the project team conquered a number of key technologies in the Fengyun-3E star infrared hyperspectral data, dual-frequency microwave active detection data, and night low-light data processing and application. The research results complement the current global The 6-hour assimilation of the numerical forecast in the satellite observation window is blank, and it has an important role in improving the timeliness and accuracy of the global numerical weather forecast.
■ Fengyun-3E is the world's first meteorological orbiting earth observation satellite in the morning and dusk, which will further reflect the global observation data value and business uniqueness of Fengyun-3
The morning and dusk orbit satellites refer to the satellites at the orbital descending point of the sun-synchronous near-polar orbit satellites at about 6 am, and the local time of observation is always in the early morning and evening. The Fengyun-3 dawning orbit satellite (Fengyun-3E star) is expected to be launched in 2020. It is the first satellite in the 03 batch of Fengyun-3 plans, and it is also the first dawning orbiting earth observation satellite for meteorological applications in the world.
At present, European and American operational polar orbiting meteorological satellites use the European Metop satellite for the morning orbit and the US NPP satellite for the afternoon orbit. The bilateral network data exchange and sharing collaborative network observation model is used. China's second-generation polar-orbiting meteorological satellite Fengyun-3 has also been upgraded and realized the operational capabilities of satellite networking observations in the morning and afternoon. The orbiting Fengyun-3 C observation time is close to the European Metop satellite, Fengyun-3. The observation time of D star is close to the NPP satellite of the United States.
"The above satellite observation time is either concentrated around 10 o'clock or around 13:00. From the perspective of the numerical weather forecast model assimilation requirements, there are always two to three orbital satellite observation blanks around the world within a six-hour assimilation time window. Zhang Peng, the person in charge of the project and deputy director of the National Satellite Meteorological Center, said that although the data quality of the Fengyun-3 satellite has passed the European and American numerical model tests and is recognized to have stable and good quality, due to the fact that the Fengyun-3 satellites C and D are respectively It overlaps with the observation time and area of Metop satellite in Europe and NPP satellite in the United States. Its data is only used as a backup of business assimilation data in the global numerical weather forecast model in Europe and America. Compared with foreign Metop satellites and NPP satellites in the same period, the global observation data value of Fengyun-3 satellite has not been fully reflected, and the uniqueness of business needs to be further improved.
To this end, aiming at the key technology of Fengyun-3 E data processing and application, the project carried out joint technical research on the United Nations Meteorological Center, Shanghai Typhoon Research Institute of China Meteorological Administration, Guangzhou Tropical Marine Meteorological Research Institute, Fujian Meteorological Observatory and other units.
■ The test results show that the data of the morning or dusk satellites have a certain positive effect on global numerical forecasting; important results such as simulation calculations and assimilation modules have been applied to the design and development of morning or dusk satellites and loads
The project team developed a calculation method for atmospheric radiation transmission based on the spectral weighting of atmospheric topographic radiation characteristics, dual-frequency dual-polarization complex sea surface scattering, and lunar low-light scattering, etc., and realized the morning and dusk orbit satellite infrared hyperspectral atmospheric sounder, wind field measurement radar, and The medium-resolution spectral imager-low-light type three new remote sensing instruments were simulated and calculated, and a simulation data set was generated. On the basis of instrument simulation, key pre-processing techniques such as geographical and geometric positioning, spectrum and radiation calibration, and instrument sensitivity analysis under the conditions of large temperature changes and complex lighting conditions in the morning and dusk satellites were completed.
The project team developed an assimilation module suitable for the morning and dusk orbit infrared hyperspectral, wind field radar, and microwave temperature and humidity meter. The test results show that the morning and dusk satellite data has a certain positive effect on global numerical prediction, especially in the southern hemisphere. Aiming at the characteristics of low sun altitude angle and complex lighting conditions in the morning and dusk orbit, corresponding identification algorithms such as morning fog, fire, and strong convection were developed. This algorithm has been applied to the information extraction of the morning and dusk periods of the Fengyun-4 stationary satellite, and has achieved good application results. .
At present, the project team has integrated the above-mentioned research results into a “synthetic demonstration platform for satellite observation simulation and data preprocessing”, and has satellite satellite data simulation calculation, preprocessing calculation, forward simulation result display, assimilation product and weather monitoring product display, etc. Features. In addition, the research results of the project have been applied in the medium-resolution spectral imager-low-light dynamic range analysis, stray light simulation and suppression, etc., effectively promoting the design and development of morning and dusk satellites and loads; infrared hyperspectral atmospheric detection The research achievements of the instrument have been applied to the construction of the Fengyun-3 D satellite ground application system. The research work in the application field will significantly promote the application speed and application efficiency of the data after the morning and dusk orbit satellites are launched.
"This research is focused and rich in results, and will further enhance the international influence of Fengyun satellites." Zeng Qingcun, leader of the project acceptance expert group and an academician of the Chinese Academy of Sciences, said that the development of the Fengyun 3 morning and dusk orbit satellite with numerical weather forecasting as the main application target In the future, it will have unique advantages in weather consultation, early warning of tropical cyclones and other extreme meteorological disasters, climate monitoring, air quality monitoring, etc., and will form a cooperative situation in the international business satellite stage that has both unique features and complementary advantages in Europe and the United States. .
(Source: "China Meteorological News" December 16th edition responsible editor: Shen Minxia)