â â in this research, temporal and spatial behavior of subtropical high pressure was studied at the level of 600 hpa. this study has been done using daily data of geopotential height at 12 gmt in ncep/ncar database with spatial resolution of 2.5ã2.5 degree in a 55 years period including 20089 days from january, 1st, 1951(dey, 11th, 1329) to december, 31st,2005(dey, 10th,1384). at first, the m...