The rate of sea-level rise
Résumé
Present-day sea-level rise is a major indicator of climate change(1). Since the early 1990s, sea level rose at a mean rate of similar to 3.1 mm yr(-1) (refs 2,3). However, over the last decade a slowdown of this rate, of about 30%, has been recorded(4-8). It coincides with a plateau in Earth's mean surface temperature evolution, known as the recent pause in warming(1,9-12). Here we present an analysis based on sea-level data from the altimetry record of the past similar to 20 years that separates interannual natural variability in sea level from the longer-term change probably related to anthropogenic global warming. The most prominent signature in the global mean sea level interannual variability is caused by El Nino-Southern Oscillation, through its impact on the global water cycle(13-16). We find that when correcting for interannual variability, the past decade's slowdown of the global mean sea level disappears, leading to a similar rate of sea-level rise (of 3.3 +/- 0.4mm yr(-1)) during the first and second decade of the altimetry era. Our results confirm the need for quantifying and further removing from the climate records the short-term natural climate variability if one wants to extract the global warming signal(10).