Remote sensing of PWV using ground-based GPS data in Wuhan region

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Astrometry, Gps, Precipitable Water Vapor (Pwv), Weighted Mean Temperature Of Troposphere, Dry Air Zenith Delay (Dzd), Radiosonde

Scientific paper

Since early nineties last century, ground based GPS meteorology has been getting great progress in the world. Many countries including China have been constructing continuous GPS network for the purpose of research and application of this new technology. The results from these networks are encouranging and then near real-time estimation of Precipitable Water Vapor (PWV) are undergoing to build a perfect system in some countries too. Despite of these, one fundamental element is usually neglected, which was found by analyzing the radiosonde data collected in Wuhan Observatory to prepare for the incoming ground-based GPS meteorology application in Wuhan. That is the accurate model of Dry air Zenith Delay (DZD) in certain region. Usually, three most popular Dry air Zenith Delay models - Saastamoinen (SAAS), Hopfield and Black are believed to be accurate in several millimeters and then are thought to be almost no influence on the estimation of PWV. In practice, due to the relationship between DZD and the temperature and pressure profile above site, DZD models in different regions may be a little different from each other. To reduce the influence of DZD model errors on the estimation of PWV, DZD models accuracy should be investigated so that a precise model suitable to this region is obtained. This paper is trying to do some work on this aspect using radiosonde data in Wuhan region. The following results indicate that there is a systematic error which can be up to more than 16 mm in the three popular DZD models, which will introduce more than 2 mm into the result of PWV. Therefore, a bias and some scale parameters are introduced in these models to eliminate the systematic errors. The parameters are estimated using the Least Squares method and are shown in a table. To validate these models after calibration, a set of data was analyzed. The results show that the influence of DZD on PWV is less than 1 mm after calibration in Wuhan. On the other hand, the same case occurs on another fundamental element - the weighted mean tropospheric temperature. With the same way as Bevis used, more than 40 days' radiosonde data were processed and it was found that there was a good linear relationship between the mean tropospheric temperature and the surface temperature in Wuhan area while linear regression was involved in analysis. Moreover, the linear equation resulted from those radiosonde data is so close to Bevis' formula that the equation owns the influence of 1 mm on the estimation of PWV in Wuhan compared with Bevis'.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Remote sensing of PWV using ground-based GPS data in Wuhan region does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Remote sensing of PWV using ground-based GPS data in Wuhan region, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Remote sensing of PWV using ground-based GPS data in Wuhan region will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1165345

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.