NOC contributes to NASA-led study revealing the causes of sea level rise since 1900

The NOC has contributed to a new study by NASA, published in Nature, which reveals new insights into the processes driving ocean sea level variations for over a century, helping us prepare for the rising seas of the future. Using recent improvements to the global tide gauge data set, supplied by the NOC, the study shows for the first time that we have identified all the key processes driving sea level changes and their relative contributions. The new work explains all of the complex changes in rates of sea level rise since 1900 to the present day. It confirms that the acceleration in sea-level rise since the 1970s is caused by the combination of thermal expansion of the ocean and increased ice-mass loss from Greenland.

Key to the new results was a substantially extended sea level data set using the Permanent Service for Mean Sea Level (PSMSL) which is curated by the NOC, as well as digital document archives worldwide. This data set was supplied by co-author Peter Hogarth who is a PhD student at the NOC and the University of Liverpool. Peter has used data archaeology to recover old and “forgotten” data, and is developing novel ways of merging it with modern data to answer vital questions about the acceleration of sea level rise.

Peter, commented, “It’s rewarding to see the results of this data archaeology effort now being utilised in sea level studies by some of the leading researchers in this field, and it has been a pleasure to be able to contribute to this important work, which has pushed our state of understanding of changes in sea level a good step forward.

NOC’s Chief Scientist for International Development, Professor Kevin Horsburgh, commented, “This recent work underlines the importance of maintaining a quality-controlled global sea level record such as the Permanent Service for Mean Sea Level, and also the need to retrieve and digitise long sea level records. Improving our knowledge of how sea level has changed during the industrial period will help us protect vulnerable coastal communities in the future, all around the world”