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The Jason-1 verification phase has proven to be a unique and successful calibration experiment to quantify the agreement with its predecessor TOPEX/Poseidon. Although both missions have met prescribed error budgets, comparison of the mean and time-varying sea surface height profiles from near simultaneous observations derived from the missions' Geophysical Data Records exhibit significant basin scale differences. Several suspected sources causing this disagreement are identified and improved upon, including (a) replacement of TOPEX and Jason project POE with enhanced orbits computed at GSFC within a consistent ITRF2000 terrestrial reference frame, (b) application of waveform retracking corrections to TOPEX significant wave height and sea surface heights, (c) resultant improved efficacy of the TOPEX sea state bias estimation from the value added sea surface height, and (d) estimation of Jason-1 sea state bias employing dual TOPEX/Jason crossover and collinear sea surface height residuals unique to the vali...

Data on quiet-time ionospheric fluctuations on scales from 1 km to thousands of kilometers are reviewed. The effect of the fluctuations on satellite altimeter measurements are discussed, and corrections for both small scale and large-scale fluctuations are given. Large scale changes are considered to be those on scales greater than 500 km or 1 hr. Temporal changes were found to occur on solar, seasonal, and diurnal scales. Spatial variations include the equatorial anomaly and the mid-latitude trough. The correlation distance of the ionosphere (70 percent correlation) was approximately 2500-3000 km east-west and 1600 km north-south. It is shown that small scale flutuations can be described by a power law spectrum with a one-dimensional index of -1.5 to -2.0. The observed spectrum of density flutucations gave a vertical line-of-sight path-length fluctuation of 1-40 mm, on a horizontal scale of 1-500 km, for a radio signal at 13.7 GHz.