30 January 2018: The World Meteorological Organization (WMO) has confirmed that 2015, 2016 and 2017 are the three warmest years on record, with 2016 holding the global record at 1.2°C above preindustrial levels. Meanwhile, the Institute of Atmospheric Physics of the Chinese Academy of Sciences (IAP CAS) has found that 2017 was the hottest year ever recorded for the world’s ocean.

According to a WMO analysis, 2017 had a global average surface temperature of approximately 1.1°C above pre-industrial levels, and was the warmest year without an El Niño, which tends to increase global annual temperatures.

Discussing the analysis, WMO Secretary-General Petteri Taalas underscored that the long-term temperature trend is more important than the ranking of individual years, noting that 17 of the 18 warmest years on record have all been during this century. He said that, along with high temperatures in 2017, many countries experienced extreme weather. The US had its most expensive year to date in terms of weather and climate disasters, and other countries experienced devastating tropical cyclones, floods, and drought. Taalas called for increased ambition to reduce greenhouse gas (GHG) emissions and concrete actions to reduce disaster risk, particularly in the least developed countries (LDCs).

Robert Glasser, the UN Secretary-General’s Special Representative for Disaster Risk Reduction (DRR), described the three-year hot streak as “an existential threat to the planet.” He underscored that based on improved climate science, “violent and frequent” extreme weather events, such as 2017’s Atlantic Hurricane Season, can be attributed to climate change. He expressed concern that climate change, combined with poverty, the ecosystem destruction, inappropriate land use, and population growth in hazard exposed areas, can undermine efforts to eradicate poverty and hunger and lead to forced migration.

The WMO consolidated analysis draws on information from five international datasets including from the US National Oceanic and Atmospheric Administration (NOAA), the US National Aeronautics Space Administration (NASA), the UK Met Office Hadley Centre for Climate Sciences and Services, and the University of East Anglia’s Climatic Research Unit, among others.

In March 2018, the WMO will issue its full ‘Statement on the State of the Climate in 2017.’ This report will provide an overview of: temperature variability and trends; high-impact events; and long-term climate indicators, such as increasing CO2 concentrations, Arctic and Antarctic sea ice, sea level rise, and ocean acidification. The Statement will also include information on human, socio-economic, and environmental impacts that will contribute to a UN-wide policy brief for decision makers on the interlinkages between weather, climate, water, and the Sustainable Development Goals (SDGs).

A separate a study by IAP CAS published in the journal ‘Advances in Atmospheric Sciences’ finds that 2017 was the hottest year ever recorded for the world’s ocean. The report shows that ocean warming in 2017 occurred in most parts of the world, with the Atlantic and the southern hemisphere ocean most impacted. The study highlights that more than 90% of the Earth’s climate-related heat is absorbed by the ocean, without which, climate change would have accelerated further than it has to date. The WMO has also said that global ocean heat content in 2017 was at or near record-high levels. [WMO Press Release, January 2018] [UNISDR Press Release] [UN Press Release] [UNFCCC Press Release on Ocean] [WMO Press Release, November 2017] [Publication: 2017 was the Warmest Year on Record for the Global Ocean]