The Sentinel

The Copernicus Sentinel-6 Poseidon-4 dual-frequency (C- and Ku-band) radar altimeter uses an innovative interleaved mode that has improved performance compared to previous satellite altimeter designs. Credit: ESA/ATG medialab

Monitoring sea level rise goes prime time with the Copernicus Sentinel.

Following liftoff last November and more than six months spent carefully calibrating the most advanced mission dedicated to measuring sea-level rise, Copernicus Sentinel-6 Michael Freilich is now operational – meaning that its data are available to climate researchers, ocean-weather forecasts and other data users.

Why it's important.

Sea-level rise is a key indicator of climate change so accurately monitoring the changing height of the sea surface over decades is essential for climate science, for policy-making and, ultimately, for protecting the lives of those in low-lying regions at risk.

Improvement of Sentinel-6 significant wave height with respect to Jason-3. Over the last six months Copernicus Sentinel-6 Michael Freilich has been orbiting in tandem with current altimetry reference mission, Jason-3, so that the satellites have the same ‘view’ of the ocean. Establishing the differences between Sentinel-6 and Jason-3 is important if stability in the sea-level rise time series from satellite altimetry is to be maintained. The plot shows the standard deviation of the significant wave height over ocean for different significant wave heights for a full 10-day cycle of Copernicus Sentinel-6 and Jason-3 using low-resolution mode data. Significant wave height is defined as the upper-third of wave height for a given sample of sea state. The plot highlights the improved (lower) significant wave height noise from Copernicus Sentinel-6 compared to Jason-3. The background bar chart shows the percentage number of data points as a function of the significant wave height (0.1 m binning). Credit: CLS