Last week, this column reported on a bulletin released by the World Meteorological Organization (WMO), which documented how the greenhouse gas (GHG) concentrations in the atmosphere increased throughout 2020. The global pandemic lockdowns made just a small dent in this rise. This week, there comes a longer report on the planet’s climate from the organization. The provisional State Of The Climate In 2020 report, released on 2 December, makes for some grim reading. The most worrying takeaway from the report is that 2020 is going to be one of the three warmest years on record. Currently, 2016 is the hottest and 2019 is the second hottest year on record. 2020 joining that club would mean that the past six years (2015-2020) would turn out to be the six hottest years on record.
The annual WMO report looks at the overall climate situation through a variety of lenses. And by almost any parameter, this has been a bad year. The global mean temperature this year was 1.2 degree Celsius above pre-industrial levels. Among other things, this also means that the time window to keep global warming down to 1.5 degree Celsius above pre-industrial levels is closing fast. Earlier this year, the WMO had warned that there is a 70% chance that multiple months in the coming five years will breach this heat threshold. The final 2020 temperatures will not be tallied until the year is over, but even with the January-October data, 2020 is quite close to the record heat seen in 2016.
And here’s the kicker. 2016 was a year with an exceptionally strong El Niño, a weather phenomenon over the Pacific Ocean, which added to global heat that year. 2020, on the other hand has had weak to neutral El Niño conditions, and, since September, cooling La Niña (a weather pattern over the Pacific Ocean) conditions have set in. So even without El Niño conditions, 2020 has been an extremely hot year. It could well be the hottest.
The report also states that the global ocean continues to heat up, as it has absorbed over 90% of the heat generated due to man-made climate change since 1970. The top 2,000m of the ocean is heating at record levels. The report also says that the global mean sea level rise is holding steady at 3.3mm/year and the continuing loss of Arctic sea ice and the melting of the Greenland ice sheet is contributing to this. As the global ocean heats up, the instances of marine heatwaves also rise. Among other effects, this spells havoc for coral reefs and fish stocks. According to the WMO report, 82% of the global ocean experienced at least one marine heatwave this year, with 43% recording a strong heatwave.
#ClimateChange continues its relentless march.— World Meteorological Organization (@WMO) December 2, 2020
WMO #StateofClimate report:
2020 is on track to be one of the three warmest years on record. 2011-2020 will be the warmest decade on record
Warmest 6 years have all been since 2015#ClimateAction pic.twitter.com/na6m1aiWid
Marine heatwaves are also responsible for supercharging tropical cyclones and hurricanes, as we’ve seen this year with cyclone Amphan. Above-normal Bay of Bengal surface temperatures contributed to cyclone Nivar last week, and also to cyclone Burevi, which will hit southern Tamil Nadu and Kerala today. Till 17 November, there were 96 named tropical storms around the world, and 30 tropical cyclones in the North Atlantic Ocean, a record.
The report also looks at instances of high-impact climate events of the year, and mentions the fat that India saw one of its two wettest monsoons this year (since 1994) with average rainfall between June-September measuring 9% higher than the global average. As we’ve seen earlier, with rising temperatures, the Indian monsoon is slated to become more extreme over the century.
The news, in short, is bad. December 12 will mark five years since the historic Paris climate agreement. With the next major climate summit postponed till November 2021 due to covid-19, the time to put the climate change genie back into the bottle is running out.