X-Band Weather Radar Network in Chengdu

Operational weather radar in CINRAD network has been an important instrument for the surveillance and monitoring of server weather system over China. However, due to the broadening beamwidth in far range and the earth curvature, the observation of lower altitude from 0.01 km to 3 km has usually been missed at many locations. Yet this layer of atmosphere observation is very critical to the recognition of the server weather system, such as tornado, downburst, thunder storm. The distributed weather radar network with collaborative adaptive sensing in CASA project has shown excellent performance in improving the coverage of lowest portion of atmosphere.

This paper describes the plans for deployment of a CASA type network in the Chengdu basin. This dense network will be used to detect server weather events in the lowest 3 km of troposphere in Chengdu Plain and evaluate the weather condition near airport. A distributed X-band weather radar network with adaptive sensing mode is designed and being implemented by CUIT in Chengdu. The paper will describe the infrastructure and weather radar system in this radar network, as well as the preliminary observation data collected by some radars this network.

This Chengdu basin radar network (CBRN) will consist of four Doppler weather radar nodes. One of them is polarimetric weather radar, which has been deployed in CUIT campus (CD radar) with a klystron transmitter. Other three are single-polarization radars with solid-state transmitter that will be deployed in Longquanyi campus of CUIT (LQ radar), Tianfu newly distinct (TF radar) and Ziyang City (ZY radar). These four radars can construct a diamond framework of CD-LQ-TF-ZY or two triangle frameworks of CD-LQ-TF and LQ-TF-ZY. Except for the distance between CD and ZY is more than 80 km, other radar nodes are within 50 km away from the next units which is within beam coverage of 1-km height.

Now three radar nodes of network have been deployed. The data are being collected and tested over the last several months. Some radar data for the observation of convective precipitation have been obtained will be described. After its full completion and calibration, The Chengdu Basin Radar Network will be used for continuous observation in the plateau-basin in this specific region and provide service for weather conditions near the new Chengdu airport.