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Abstract

Global mean sea level rise is one of the direct consequences of the actual global warming. This rise has been monitored for years by satellite altimetry missions which provide high quality data at nearly global coverage. This global rise is caused by global ocean warming (known as thermosteric sea level) and the continental freshwater discharge from land ice melting (i.e., Greenland and Antarctica ice sheets and mountain glaciers; known as barystatic sea level). On top of the background sea level trend, large interannual variability can occur which can be attributed to natural climate mode of variability (such as ENSO, PDO, etc). Since 2005 and at global scale, ocean warming and barystatic sea level can be assessed by complementary observing systems such as Argo profiles and GRACE/GRACE-FO data, respectively. In this study, we investigate the extreme El Nino event occurring in 2015-2016 and its imprint on the global mean sea level change by assessing all the different components of the sea level budget. Over 2014-2016, we find that the global mean sea level experiences a rise of 1.5 cm over 24 months. 30% of this rise can be attributed to global ocean warming and 70% to the imports of continental ice melt. We then assess a complete continental freshwater budget (Greenland, Antarctica and terrestrial water storage) to quantify this extreme El Nino event and its imprint on global mean sea level rise.