Last updated December 4, 2018

Sea Surface Temperature Increase

The amount of heat absorbed by the oceans has surged in the past few decades, contributing to more intense storms, sea level rise, sea ice melt, storm surge flooding and widespread ecosystem change.

Physical considerations

Ocean warming dominates the increase in energy stored in the climate system. About 93 percent of the heat trapped by greenhouse gas emissions between 1971 to 2010 has made its way into the oceans.[1] More than a third of this heat has ended up in the deep ocean instead of remaining at the surface.

Sea surface trends

On a global scale, ocean warming is largest near the surface. Over the period 1971 to 2010, the upper 246 feet (75 meters) warmed by 0.20°F [0.16 to 0.23°F] or 0.11°C [0.09 to 0.13°C] per decade.[1] Across the four decades from 1971 to 2010, this sums to 0.8°F (0.44°C) of sea surface warming.

An independent 2018 analysis finds that the ocean gained 1.33±×10^22 joules of heat per year between 1991 and 2016, equivalent to a planetary energy imbalance of 0.83 watts per square meter of Earth’s surface.[2] The results suggest that ocean warming is at the high end of previous estimate.

Combined sea and land surface global trends

It is certain that global mean surface temperature has increased since the late 19th century.[1] Each of the past three decades has been successively warmer at the Earth’s surface than any the previous decades in the instrumental record, and the decade of the 2000’s has been the warmest.[1] 

The globally averaged combined land and ocean surface temperature data shows a warming of 1.5°F (0.85°C) over the period 1880–2012.[1]


IPCC models project further ocean warming in the top 100 meters of 0.9°F (0.6°C) to 3°F (2°C) by 2100, depending on future emissions reductions. For the top 1000 meters, the IPCC expects that warming will increase by 0.5°F (0.3°C) to 0.9°F (0.6°C).[1]