Jason-1 / Jason-2 metocean comparisons and monitoring

The initial tandem phase of the Jason-2 mission is important for the calibration of the entire altimetric system, not just the records of sea surface height. However, as well as allowing a bulk comparison of metocean parameters such as wave height and backscatter strength (used to infer wind speed), it affords a more detailed opportunity to understand the artefacts within each instrument. The wave height comparison shows no bias between the instruments, with the mismatch error of consecutive points independent of one another. The backscatter difference is not a simple offset, but has a trend with weak non-linear variations. The technique for backscatter monitoring using Ku-/C-band differences is validated during the tandem phase, and extended to show 59-day oscillations in Jason-1 data, probably associated with spacecraft manoeuvres.