Major greenhouse gases hit record highs in 2014

All the major greenhouse gases that fuel global warming hit record highs last year, while the planet's surface temperature reached its hottest point in 135 years, international researchers said Thursday.

The findings of the 2014 State of the Climate report -- a peer-reviewed study that examines temperature, precipitation and weather events experienced around the world -- were released by the National Oceanic and Atmospheric Administration.

A total of 413 scientists from 58 countries around the world contributed to the report, which is based on data collected by environmental monitoring stations and instruments on land, water, ice and in space.

"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," said the study.

Amid worldwide heat records, eastern North America was the only major region of the world to experience below-average annual temperatures.

"Europe observed its warmest year on record by a large margin, with close to two dozen countries breaking their previous national temperature records," said the study.

"Many countries in Asia had annual temperatures among their 10 warmest on record; 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."

In Latin America, Mexico had its warmest year on record, while Argentina and Uruguay each had their second warmest year on record.

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 millimeters (2.6 inches) greater than the 1993 annual mean," when satellite measurements of ocean levels began, said the study.

The full report is published in the Bulletin of the American Meteorological Society.