Topic 1e - Sea level rise (part 1): overview with Dr Anny Cazenave

Altimetry has been measuring the sea levels, over all the oceans since the early 1990s.

By averaging these levels over the oceans, and looking at the variations on the whole period, one can estimate the global sea level rise with an accuracy of 0.5 mm/yr.

Sea levels across the globe are on the rise due to global climate change, and even a small, permanent increase in the global sea level could have major consequences for the Earth’s populations - particularly for those situated in coastal regions.

Sea level is one of the Essential Climate Variables, and an indicator closely monitored by the IPCC.

Optional mini task:

Explore the altimetry sea level data here. From looking at a number of different altimetry sensors on the interactive graph, how has sea level changed over recent years? How do the trends vary between different sensors and different zones?

Featured Educators:

  • Dr Anny Cazenave

Explore the data

EUMETSAT Oceans MOOC Data Viewer

View featured satellites on the satellite tracking app

Don’t forget you can download the video and transcript with the links on the right.



This image is a model of the ‘geoid’ created by ESA’s GOCE mission. It is the most accurate model of the ‘geoid’ ever produced, which will be used to further our understanding of how Earth works.

The colours in the image represent deviations in height (–100 m to +100 m) from an ideal geoid. The blue shades represent low values and the reds/yellows represent high values.

Sea Level Trends

Sea level trends were estimated using data from TOPEX/Poseidon (T/P), Jason-1, and Jason-2, which have monitored the same ground track since 1992.

Satellite altimetry

Illustration of how altimetry measurement works for Jason satellite

Global mean sea level change

Global mean sea level change graph 1992-2016

Regional sea level change

Regional sea level change graph

Sea Level Anomaly (cm)

Sea level anonomalies in the Gulf Stream from Sentinel-3, Jason-3, Jason-2, Cryosat-2, and SARAL/AltiKA data