It was.
From Morner:
So, for example, those people in the IPCC [Intergovernmental Panel on Climate Change], choose Hong Kong, which has six tide gauges, and they choose the record of one, which gives 2.3 mm per year rise of sea level.
Then, in 2003, the same data set, which in their [IPCC’s] publications, in their website, was a straight line—suddenly it changed, and showed a very strong line of uplift, 2.3 mm per year, the same as from the tide gauge.
And he was lying. What he was stating has no truth in it. Sorry, the dataset is present in the paper and links I quoted. I am telling you precisely what what happened. One of the early satellites, working between 1992-1996 provided wrongly calibrated results. This was discovered by scientists based on the observations made by the newer satellites (5-6 of them) that were put on orbit between 1996-2005, the calibration mistake was identified and corrected for the old satellite data. The IPCC may have simply reported the new corrected data set along with the data of the newer satellite dataset in a new report.
That is what actually happened.
Here are the excerpts
The six main groups that provide satellite-altimetry-based GMSL estimates (AVISO/CNES, SL_cci/ESA, University of Colorado, CSIRO, NASA/GSFC, NOAA) use 1 Hz altimetry measurements from the T/P, Jason-1, Jason-2 and Jason-3 missions from 1993 to 2018 (1993–2015 for SL_cci/ESA). Each group processes the 1 Hz data with geophysical corrections to correct the altimetry measurements for various aliasing, biases and drifts caused by different atmospheric conditions, sea states, ocean tides and others (Ablain et al., 2009).
Recently, the comparisons of the GMSL time series derived from satellite altimetry with independent estimates are based on tide gauge records (Valladeau et al., 2012; Watson et al., 2015) or on the combination of the contribution to sea level from thermal expansion, land ice melt and land water storage (Dieng et al., 2017). They have shown that there was a drift in the GMSL record over the period 1993–1998. This drift is caused by an erroneous onboard calibration correction on TOPEX altimeter side-A (denoted TOPEX-A). TOPEX-A was operated from launch in October 1992 to the end of January 1999. Then the TOPEX side-B altimeter (denoted TOPEX-B) took over in February 1999 (Beckley et al., 2017). The impact on the GMSL changes is −1.0 mm yr−1 between January 1993 and July 1995, and +3.0 mm yr−1 between August 1995 and February 1999, with an uncertainty of ±1.7 mm yr−1 (within a 90 % CL, Ablain, 2017).
The maximum trend difference between all time series over 1993–2017 is lower than 0.15 mm yr−1, representing less than 5 % of the GMSL trend. The differences observed at interannual timescales are also small (<2 mm). By correcting the drift of TOPEX-A using either of the available empirical corrections (WCRP Global Sea Level Budget Group, 2018), the differences among solutions remain the same (the difference between empirical corrections being smaller than the difference between the raw GMSL time series).
Therefore, the choice of one or the other GMSL record is not decisive in this study, whose purpose is to characterize the uncertainties.