Research Group
Site Survey
Monitoring Sites
Remote Monitoring





Local topography and layout of Oma site

Oma site is located at 83.07 degrees east longitude and 32.55 degrees north latitude, the northern hinterland of Tibet plateau, with an elevation of 5032 meters.

Observation precess

2005.07-08:Infrastructure construction

2005.08-2006.12:Uninterrupted monitoring

2007.01-12:Power supply gap and monitoring stagnation

2008.11-2010.11:Continued monitoring

Monitoring equipment

Research results

1. Wind speed: It's westerly or northwesterly wind mainly, the mean value of wind speed is 6.3m/s,smaller at night, also relatively small in summer. A drawbacks is the windy weather, the maximum speed value is up to 34.7m/s in winter, equivalents to Paranal's situation(median value 6.6m/s, maximum value 47.2 m/s).

2. Atmospheric temperature: As plateau climate characteristics, the temperature changes from -22.4 to 19.3 centigrade, the mean vlaue is -1.05 centigrade and the median value is -1.0 centigrade(Paranal temperature changes from -8 centigrade to 25 centigrade in 1985-1990).

3. Atmospheric pressure: The value is relatively low all year round, it ranges between 538.1 and 561.4 hpa, with mean value 551.7hPa.

4. Relative humidity: The median value is 30% and minimum 3%, higher than 5~20% the typecal value of Paranal,but the Oma humidity is lower than Paranal's as a whole.

5. Cloud cover: The median value is lower than 4 in the daytime, better than the night results of MaunaKea in 2006, while the night value is generally better than the day value.

6. Sky brightness: up to 22.0 mag arcsec-2 in the clear night without the Moon.

7. Precipitable water vapor(PWV): The PWV value is greater in the summer than that in the winter, also greater in the daytime than that in the nighttime. The mean value of PWV is 3.9mm in 2005 and 2.8mm in 2006, usually lower than 3mm all the year round except the May to August, even lower than 1mm from November to January next year. It is better than LaSilla and simillar to Paranal.

8. Seeing: The typical value is from 0.7 to 0.8 arc-second, better than LaSilla's and equivalent to Paranal, while the observational data is not enough and the processing of the data need improve.

Update: 2014-01-22

© Site Survey Group,NAOC