A new study paper out in nature (Nature Climate Change / 2014 / doi:10.1038/nclimate2159), explores why the rise of sea-level has slowed in the last decade.

This slow-down coincidences with the observed climate hiatus (IPCC AR5, Ocean heat content uptake). Because  heat is distributed differently, depending on the state of ENSO (between El Nino or La Nina).

A GMSL trends computed over two time spans (January 1994–December 2002 and January 2003–December 2011) using satellite altimetry data from five processing groups (see Methods for data sources).

Abstract Present-day sea-level rise is a major indicator of climate change. Since the early 1990s, sea level rose at a mean rate of ~3.1 mm yr⁻¹. However, over the last decade a slowdown of this rate, of about 30%, has been recorded. It coincides with a plateau in Earth’s mean surface temperature evolution, known as the recent pause in warming. Here we present an analysis based on sea-level data from the altimetry record of the past ~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 Niño–Southern Oscillation, through its impact on the global water cycle. 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 ± 0.4 mm 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.

However, last year a study hinted at significant future sea-level rise – In Ancient Ice, Clues That Scientists Are Underestimating Future Sea Levels

Related 

• RealClimate: It Never Rains but it Pause
• RealClimate: Global Temperature 2013
• Slower sea level rise linked to El Nino and natural weather patterns
• Cutting Short-lived Pollutants Can Slow Sea Level Rise
• Australia’s Flooding Rains Briefly Slowed Sea Level Rise

Teaser image via Ocean Defender.