A new report provides the latest checkup on the health of the global climate system.
Ocean surface temperatures in 2013 were also among the top 10 warmest. But more notable is the amount of heat stashed in the upper half mile of the ocean, which has increased steadily and reached a record high in 2013.
“Warming in the upper (up to 700 meters) oceans accounts for about 63 percent of the total increase in energy storage in the climate system from 1971 to 2010,” the report said.
Scientists have posited that the apparent “pause” in global warming is being driven by increased heat storage in this layer of the ocean. Ocean warming coupled with melting ice has contributed to sea level rise, which also reached record highs in 2013.
Arctic sea ice extent, glaciers and late spring snow cover all felt the heat last year as well. Each continued a trend in line with the impacts of climate change.
With 2014 halfway over, there are no signs that the globe’s hot streak is ending. Data through May shows that this has been the planet’s fifth-warmest start to the year on record. Jessica Blunden, a scientist who works with NCDC, said that preliminary data show that June’s ocean temperatures were the hottest on record, a sign that 2014 is on track to be one of the hottest years recorded. Another factor tipping the scales in that direction is the impending El Niño, a climate phenomenon that usually boosts global temperatures. Other indicators like greenhouse gas emissions, Arctic sea ice and deep ocean heat are also likely to keep following suit.