The year 2017 was the third-warmest on record globally, behind 2016 (which was first warmest) and 2015. That’s according to the annual State of the Climate report, released on August 1, 2018. The report also described record-high greenhouse gas concentrations and rises in sea level in 2017 as well.
The State of the Climate report is an international, peer-reviewed publication released each summer, based on contributions from more than 500 scientists in 65 countries around the world. It provides a detailed update on global climate indicators, notable weather events, and other data collected by environmental monitoring stations and instruments on land, water, and ice, and in space.
Here are some highlights of the report, from a NOAA statement:
Levels of greenhouse gases were the highest on record. Major greenhouse gas concentrations in the atmosphere – including carbon dioxide (CO2), methane and nitrous oxide – reached new record highs. The 2017 average global CO2 concentration was 405 parts per million, the highest measured in the modern 38-year global climate record and records created from ice-core samples dating back as far as 800,000 years.
Sea level rise hit a new high – about 3 inches (7.7 cm) higher than the 1993 average. Global sea level is rising at an average rate of 1.2 inches (3.1 cm) per decade.
Global land and ocean combined surface temperature reached a near-record high. Depending on the dataset, average global surface temperatures were 0.68-0.86 of a degree F (0.38-0.48 of a degree C) above the 1981-2010 average. This marks 2017 as having the second or third warmest annual global temperature since records began in the mid- to late 1800s.
Sea surface temperatures hit a near-record high. Though the global average sea surface temperature in 2017 was slightly below the 2016 value, the long-term trend remained upward.
Arctic maximum sea ice coverage fell to a record low. The 2017 maximum extent (coverage) of Arctic sea ice was the lowest in the 38-year record. The September 2017 sea ice minimum was the eighth lowest on record, 25 percent smaller than the long-term average.
The Antarctic also saw record-low sea ice coverage, which remained well below the 1981-2010 average. On March 1, 2017, the sea ice extent fell to 811,000 square miles (2.1 million square kilometers), the lowest observed daily value in the continuous satellite record that began in 1978.
Drought dipped and then rebounded. The global area of drought fell sharply in early 2017 before rising to above-average values later in the year.
Unprecedented multiyear coral reef bleaching continued. A global coral bleaching event spanned from June 2014 through May 2017, resulting in unprecedented impacts on reefs. More than 95 percent of coral in some affected reef areas died.
Heat in the upper ocean hit a record high, reflecting the continued accumulation of thermal energy in the uppermost 2,300 feet of the world’s oceans.
Bottom line: According to the 28th annual State of the Climate report, released August 1, 2018, the year 2017 was the third-warmest year on record globally, behind 2016 (first) and 2015.
Eleanor Imster has helped write and edit EarthSky since 1995. She was an integral part of the award-winning EarthSky radio series almost since it began until it ended in 2013. Today, as Lead Editor at EarthSky.org, she helps present the science and nature stories and photos you enjoy. She also serves as one of the voices of EarthSky on social media platforms including Facebook, Twitter and G+. She and her husband live in Tennessee and have two grown sons.