The absolute calibration of altimeter satellites using GNSS buoy and tide gauge near the sea of Qingdao, China

Abstract:

In this paper, the absolute calibration of altimeter satellites are detailed using the calibration facilities, which is located northeast of Qingdao in the China Yellow Sea. The calibration phrase lasts from July to October 2014, corresponding to the altimeter datasets: Jason-2 Pass No.147, Cycle No.75-82 and HY-2 Pass No.153, Cycle No.221-232, both at 20 Hz rate. We adopt the calibration strategy combined direct and indirect methods by using Global Navigation Satellite System (GNSS) buoy and tide gauge together. All calibration results have been determined using a regional and precise detailed geoid, along with a good knowledge of local ocean circulation and a well‐defined sea‐surface calibration methodology. The wet troposphere delays and the ionosphere path delays have also been examined with respect to in-situ GNSS arrays. The altimeter bias values for Jason-2 is B= +13.8 cm ± 3.6 cm, the same level compared to other dedicated calibration sites around the world. The initial bias values for HY-2 is B= –46.2 cm ± 5.6 cm, it is the result derived from IGDR dataset which contains a peculiarity in the net instrument correction.