China’s meteorological satellite observation marches into the “FY-4A” era

26-09-2017Source:China Meteorological News Press

Full Disk Image produced by FY-4A.

On September 25, FY-4A, the new-generation geostationary orbital meteorological satellite of China, is officially put into use after being tested to have met all the relevant delivery requirements. As the pioneer of FY-4 series, FY-4A represents the most advanced weather satellite in the world and marks a significant step in upgrading technologies of geostationary meteorological satellite, identifying an important milestone for the development of weather satellites in China.

FY-4A satellite captures a view of cyclone storm cloud systems over northern Australia on Feb. 20, 2017.

FY-4A is the first of Chinese second-generation geostationary meteorological satellite. On December 11 last year, FY-4A was successfully launched at Xichang Satellite Launch Center, southwest China's Sichuan Province. After that it is situated in orbit 36,000 km above Earth at 99.5°E for in-orbit testing and relocates to 105°E for observation purpose on May 25 this year. The in-orbit testing result showed that all the functional parameters and performance indicators have met the desired requirement, demonstrating operational readiness of its payloads and corresponding services.

The image vividly shows how the water vapor was transported when the rainy and snowy weather swept central and eastern China on Feb. 21, 2017. The air current crossing the equator from Somalia piped rich water vapor into this cold air process.

The “Game Changer” satellite kicks China’s geostationary meteorological satellite technologies into the global cutting-edge level. For the first time in the world, FY-4A is able to conduct hyper-spectral vertical atmospheric sounding on geostationary orbit. It innovatively achieves integrated payload configuration for the first time too. As a result, various instruments onboard can peacefully work on the same platform without upsetting each other. What’s more, the microwave sounding technical verification on geostationary orbit is also a first in the world.

Four new instruments are onboard with the latest independently developed weather satellite, namely, Advanced Geosynchronous Radiation Imager (AGRI), Geosynchronous Interferometric Infrared Sounder (GIIRS), Lightning Mapping Imager (LMI) and Space Environment Package (SEP). The number of channels of the scanning radiation imager AGRI hits 14 and has increased by 3.8 times as compared with that of FY-2 satellites. The temporal resolution has increased by twice and can scan the Eastern Hemisphere every fifteen minutes and produce an image of regional observation every minute at its full speed. The highest spatial resolution has increased by seven times, pointing to 500 meters. As a result, through FY-4A we can access multispectral, high-precision and quantitative observation data and images. The geosynchronous interferometric atmospheric vertical sounding GIIRS can exercise the high-precision detection of atmospheric temperature and moisture profile. LMI is unprecedentedly endowed with the capability of capturing the lightning. This powerful instrument can produce 500 images of lightning over China and neighborhoods every second, giving a new concept of monitoring and tracking severe convection weather such as thunder and lightning and rainstorm.

As a heavyweight in improving the accuracy of weather forecasting, FY-4A has changed pattern of international meteorological satellites. During the period of in-orbiting test, FY-4A carried out some monitoring tasks targeted to typhoon, sand storm, rainstorm, algal bloom caused by blue-green algae, and haze, etc. The result showed that FY-4A can clearly observe the fine detail of sand storm and internal structure of typhoon on meso- and micro-scale as well as the water vapor transport at different layers when a rainstorm occurs.

In the future, Fengyun-4A is expected to improve various weather-related services, including weather forecasting, disaster prevention and reduction, and the warning and monitoring of space weather. The capability of addressing climate change, exploring climate resources and monitoring ecological environment will also be enhanced. The first satellite of FY-4 series will find its popular use in meteorology, water conservancy, agriculture, forestry, environment, energy, aviation and ocean. In addition, it will act as a strong supporter for national strategic program such as The Silk Road Economic Belt and the 21st Century Maritime Silk Road initiatives, also known as "The Belt and Road".

As part of the capable network of weather satellites in China, FY-4A has been included in the global satellite observing system by World Meteorological Organization. It will serve as an important player and contribute to disaster preparedness and reduction and socio-economic development for China and the Asian-Pacific region. (September 26)

Reporter Niu Yanyuan

Editor Wu Peng