Site Testing at the Gaomeigu Village

The work on the site testing at the Gaomeigu village Lijiang county in the northwest of Yunnan Province, was started in 1994 after the completion of the investigation on optical/infrared astronomical observatory site resources over Yunnan Province. The observation of the astro-climate conditons has been made for more than two years.The major results are given as follows: The photometrical nights are 75, the half-photometrical nights 39, the spectroscopic nights 99.5.the average of the temperature difference during night is 3.2℃, the average of the winding speed 3.6m/s, the precipitable water vapor at night is 13.0mm in the raining season and 4.3mm in the dry season respectively. The seeing measurement was made by a three-subaperture DIMM.20486 sets data obtained for 294 nights.The average of the Fried parameter is 15.53cm (FWHM =0.71).The microtemperature sensors were used to determine the atmospheric turbulence dist ribution near the ground from 6.5cm to 27m.The typical value is about 0.11 at night.The sky brightness and the extinction coefficient in B.V.colors was measured by a photometer.The means of the sky brig htness B =22^m.34/◇" and V =21^m.54/◇".The extinction coefficients K'_v =0.135 and K'_bv =0.298.