In 2014 the world’s oceans swelled, major greenhouse gases that fuel global warming hit record highs and the planet’s surface temperature reached its hottest point in 135 years, international researchers say.
The findings are contained in the 2014 State of the Climate report, a peer-reviewed study published on Thursday that examines temperature, precipitation and weather events around the world.
A total of 413 scientists from 58 countries around the world contributed to the report, the 25th in a series that is based on data collected by environmental monitoring stations and instruments on land, water, ice and in space.
The warmth reached deep into the oceans and high into the atmosphere, and scientists warned that the climate continues to change quickly compared to the pre-industrial era, with no end in sight.
"If we were to freeze greenhouse gases at their current levels, the seas would actually continue to warm for centuries to millennia," said oceanographer Greg Johnson of the National Oceanic and Atmospheric Administration (NOAA) Pacific Marine Environmental Laboratory in the US.
Many of the same trends seen in the past two decades continued in 2014.
"Carbon dioxide, methane, and nitrous oxide - the major greenhouse gases released into Earth's atmosphere - once again all reached record high average atmospheric concentrations for the year," it said.
Amid worldwide heat records, eastern North America was the only major region of the world to experience below-average annual temperatures.
"Many countries in Asia had annual temperatures among their 10 warmest on record," it said. "Africa reported above-average temperatures across most of the continent throughout 2014; Australia saw its third warmest year on record, following record heat there in 2013."
The world's oceans experienced record warmth last year, and sea level was at its highest in modern times, too.
"Owing to both ocean warming and land ice melt contributions, global mean sea level in 2014 was also record high and 67 millimetres greater than the 1993 annual mean," when satellite measurements of ocean levels began, said the report.