WASHINGTON • The Earth set a series of dire records last year, including hottest year in modern times, highest sea level and most heat-trapping gases ever emitted, a global climate report said.
A range of key climate and weather indicators indicates the planet is growing increasingly warm, a trend that shows no signs of slowing down, said the annual State of the Climate Report on Thursday. "Last year's record heat resulted from the combined influence of long-term global warming and a strong El Nino early in the year," said the report.
"The major indicators of climate change continued to reflect trends consistent with a warming planet," it added, noting that several markers - such as land and ocean temperatures, the sea level and greenhouse gas concentrations in the atmosphere - broke records set just one year earlier.
Unprecedented levels of greenhouse gases are polluting the atmosphere, acting like a blanket to capture heat around the Earth, the report said. All major greenhouse gases that drive warming, including carbon dioxide (CO2), methane and nitrous oxide, rose to new heights, it said. Atmospheric CO2 concentration reached 402.9 parts per million (ppm), surpassing 400 ppm for the first time in the modern record and in ice core records dating back as far as 800,000 years.
"Climate change is one of the most pressing issues facing humanity and life on Earth," said the publication, put together by nearly 500 scientists from around the globe and released each year by the United States National Oceanic and Atmospheric Administration and the American Meteorological Society.
The report confirmed prior announcements that last year was the hottest year since contemporary records began, marking the third year in a row that global records were broken planetwide. Both land- and sea-surface temperatures set new highs.
Melting glaciers and polar ice caps swelled the world's oceans, and the global average sea level rose to a new record high - about 8.25cm higher than the 1993 average. In the sensitive polar regions, sea ice in both the Arctic and Antarctic hit record lows.
On the rise in 2016
• Hottest year since contemporary records began.
• Major greenhouse gases, including carbon dioxide, rose to new highs.
• Global average sea level rose to a record high.
• Sea surface temperatures hit record levels.
• Average Arctic land surface temperature was 2 deg C above the 1981-2010 average.
SOURCE: NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION
Land temperatures warmed too - the average Arctic land surface temperature was 2 deg C above the 1981-to-2010 average. This represents a 3.5 deg C increase since records began in 1900.
Some extreme weather events increased, such as unusually high tropical cyclone activity. A total of 93 named tropical cyclones were observed worldwide last year, well above the 1981-to-2010 average of 82 storms.
Record-high annual temperatures swept Mexico and India. Over the northern and eastern Indian peninsula, a heatwave at the end of April saw temperatures exceed 44 deg C, contributing to a water crisis and to 300 fatalities, the report said.
Drought was unusually widespread as well. At least 12 per cent of land surfaces experienced severe drought conditions or worse each month of the year. "Drought in 2016 was among the most extensive in the post-1950 record," it said.
Meanwhile, the weather phenomenon known as El Nino, which warms waters around the equator in parts of the Pacific Ocean, was strong in the first half last year, leading to increasingly wet conditions in some places. Argentina, Paraguay and Uruguay saw repeated heavy flooding, while parts of eastern Europe and central Asia were wetter than usual.
The US state of California had its first wetter-than-average year since 2012, breaking a drought that lasted several years.