China plans to put four more Fengyun 3 meteorological satellites into orbit between 2018 and 2021, China Aerospace Science and Technology Corp announced on Wednesday. The satellites will form a network in low-orbit to enhance the monitoring of atmospheric humidity and temperature, greenhouse gases, wind and precipitation, said Zhou Xubin of CASTC.

The devices will help shorten the interval between world weather forecast updates from the current six hours to four hours, and increase the timeliness of weather disaster monitoring and forecasting accuracy, Zhou said.

China launched a Fengyun 3D at 2:35 am on Wednesday from the Taiyuan Satellite Launch Center in northern China's Shanxi province. A Long March 4C rocket carried it into space, where it entered orbit.

The Fengyun satellites are part of a series of remote-sensing meteorological satellites developed by China. Fengyun 1 and Fengyun 3 are polar orbiters, while Fengyun 2 and Fengyun 4 operate in geostationary orbit.

The Fengyun 3D is one of China's second generation of polar-orbiting meteorological satellites, and can provide global three dimensional all-weather and multispectral remote sensing images.

The satellite will form a network with the Fengyun 3C, which was launched in September 2013, to improve the accuracy of atmospheric sounding and enhance the monitoring of greenhouse gases. The network is expected to help China's disaster relief work.

The launch was the 254th mission of the Long March rocket series.

Xinhua