[1]The Institute of Atmospheric Environment;
China Meteorological Administration;
Shenyang110016;
China;
[2]Anhui Meteorological Observatory;
Anhui Key Lab of Strong Weather Analysis and Forecast;
Hefei230031;
China;
[3]Anhui Meteorological Bureau;
Hefei230031;
China;
[4]Anhui Meteorological Information Centre;
Hefei230031;
China;
[4]Anhui Meteorological Information Centre;
Hefei230031;
China;
Variational merging; L1 norm; Parameter optimization; Precipitable water vapor; Regularization parameter;