The accelerating chaos of the climate crisis

The World Meteorological Organization’s (WMO) annual State Of The Global Climate reports serve as an important snapshot of the different indicators for a warming world. In that context, the 2023 report, released on 19 March, makes for alarming reading. It confirmed that last year was indeed the hottest year ever recorded, beating the previous hottest years, 2016 and 2020, by a clear margin. Equally importantly, the global average surface temperature skated perilously close to breaching the 1.5 degree Celsius safety mark.

During the 2015 Paris Agreement, the world’s nations had agreed to work together to limit global temperature rise to 2 degrees Celsius (by 2100) above pre-industrial levels (1850-1900). Over the years, this was further refined to limiting heating to 1.5 degree Celsius above pre-industrial levels by 2100. If the world were to heat up above that threshold, the effect on natural systems, and human life would be catastrophic.

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As the WMO report shows, the world probably touched the 1.5 mark in 2023, at least temporarily. It certainly did so on specific months. According to the report, in 2023, the global average temperature was 1.45 degrees Celsius hotter than pre-industrial times, with an uncertainty of±0.12 degree Celsius. It had been established by late last year that June-November 2023 had been the hottest months ever recorded. The WMO report confirmed that 2023 was the hottest year of the hottest decade (2014-2023) on record. While this record heat was driven by the cyclicalEl Niñoclimate pattern, the underlying reason for the heating is the record levels of planet heating greenhouse gases (GHG), like CO2 and methane, in the atmosphere. The latest data for CO2 emissions in the atmosphere, from 2022, shows a 150% jump from pre-industrial levels.

Marine heatwaves and rising seas: But rising atmospheric heat isn’t the only marker of the climate crisis. They key to understanding the heating climate is how the global ocean reacts to the excess heat trapped by GHGs. In the past fifty years, the ocean has absorbed 90% of this heat, and has also absorbed the excess CO2 emitted into the atmosphere, leading to ocean acidification, leading to declining fish stocks and dying coral reefs.

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The WMO report states that the ocean heat content in 2023 was the highest on record, with a sharp rise in ocean heating in the past twenty years. Quite alarmingly, there were marine heatwaves in 66% of the global ocean in 2023, and by the end of the year, nearly 90% of the global ocean had experienced a heatwave.

“Climate change is about much more than temperatures. What we witnessed in 2023, especially with the unprecedented ocean warmth, glacier retreat and Antarctic sea ice loss, is cause for particular concern,” said WMO Secretary General Celeste Saulo.

The Antarctic and Greenland ice sheets are highly stressed, and the extent of the Arctic summer sea ice in 2023 was one of the lowest ever recorded. Combined with this, the mean global sea level rise also reached record levels, and records show that the rate of sea level rise is accelerating. Between 1993-2002, this was 2.13mm a year. Between 2014-2023, this rose to 4.77mm a year. Not only does this raise the risk of coastal inundation into low lying and coastal cities, but also makes storm surges from cyclones deadlier.

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Worsening impacts of the climate crisis: In a supplemental report, Significant Weather & Climate Events, the WMO has shown how Cyclone Mocha in the Bay of Bengal became one of the most intense cyclones ever observed. Supercharged by high sea surface temperatures in the Bay in early May last year, Mocha reached a peak of sustained winds of 210 kmph. Although it ultimately struck the Bangladesh-Myanmar border, earlier heat-fuelled cyclones like Amphan in 2020 hit Indian coastlines with devastating effect.

One of the biggest markers of global warming is the retreat of mountain glaciers, especially in the Himalaya. Rising heat is leading to glacier loss and the creation of glacial lakes, which can burst and cause devastating floods. The October glacial lake outburst flood in the Sikkim flood was one such event in 2023.

Global warming has also been playing havoc with the Indian monsoon, and in continuation of this trend, the 2023 monsoon saw 6% less rainfall below the long-term average, with violent rainfall events (like the one that caused landslides in Himachal Pradesh) alternating with deficient and intermittent rainfall.

One of the pieces of good news in the report, which the WMO called “a glimmer of hope”, is the fact that the capacity additions for renewable energy (RE) increased by nearly 50% from 2022 to 2023, reaching a total of 510 gigawatts (GW) worldwide, the fastest such growth.

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