The homogeneous and repeated data coverage over coastal regions from satellite radar altimetry is one important data source for oceanographic and geodetic applications. However, the sea surface heights (SSH) extracted from the altimeter data are often in error close to the coast, due in part to the complex nature of echoes returned from rapidly varying coastal topographic surfaces (both land an...

Based on a correlation analysis method, a subwaveform threshold retracker is developed and coded in FORTRAN for satellite altimetry to determine the leading edge and retracking gate, and to improve the precision of sea surface heights (SSHs) and gravity anomalies (GAs). Using ERS-1/ERM waveforms, the subwaveform threshold retracker outperforms full-waveform threshold retrackers at the tide gage...

In order to construct improved maps of marine gravity anomalies, we have developed and tested retracking methods for determining sea surface slopes from radar altimeter return waveforms collected by the Jason-1 mission. The accuracy of marine gravity models derived from satellite altimetry depends mainly on two factors: first, the density of ground tracks covered by the mission, and second, the...

The RA2/MWR Level 2 processing includes some algorithms designed specifically to extract geophysical measurements over different types of surfaces (ocean, sea-ice, continental ice, etc.). In order to do this, four specialised retrackers have been developed and are continuously run in parallel (over all surfaces): __ ocean retracker: optimised for ocean surfaces (operating on Ku and S bands), an...

As a new spatial measuring technic developed in 1970s,altimetry was designed to determine the sea surface height based on spatial technology, electronic technology and microwave technology. It also plays an important role in geodesy and oceanography; meanwhile, it can provide all-weather and repetitious measurements in global region for the studying of variation of SSH, earth gravity field, oce...

monitoring of water levels within the seas and oceans has been enhanced by application of satellite radar altimetry missions, compared to the traditional in-situ tide gauge measurements, due to their vast coverage and better spatial resolution. satellite radar altimetry, which is originally designed to measure global ocean surface height, has been applied to inland surface water hydrologic stud...

S U M M A R Y We have reprocessed ERS-1 radar altimeter waveforms using an algorithm designed to minimize sea surface slope error and decouple it from significant wave height (SWH) error. Standard waveform retracking estimates three parameters—arrival time, SWH and amplitude. We show that errors in retracked estimates of arrival time and SWH are inherently correlated because of the noise charac...

During the Eddy Experiment, two synchronous GPS receivers were flown at 1 km altitude to collect L1 signals and their reflections from the sea surface for assessment of altimetric precision and accuracy. Wind speed (U10) was around 10 m/s, and SWH up to 2 m. A geophysical para-metric waveform model was used for retracking and estimation of the lapse between the direct and reflected signals with...

The accuracy of sea surface heights (SSHs) estimation from satellite altimeters is strongly influenced by the microwave reflected signals (or waveforms). Waveforms in open oceans generally have ideal shapes following Brown (1977) model. However, coastal and shallow waters, are disturbed lands, thus resulting complicated waveforms (non-Brown). Non-Brown produce inaccurate SSH estimations; theref...

Zhari Namco, a large lake in the Tibetan Plateau (TP), is sensitive to climate and environmental change. However, it difficult retrieve accurate continuous levels for Namco. A robust strategy, including atmospheric delay correction, waveform retracking, outlier deletion, inter-satellite adjustment, proposed generate long-term series of Namco through multi-altimeter data. Apparent biases are fou...