2020 will remain etched in the human memory as a year that brought dual catastrophes: Coronavirus and excessive heat. 2020 is about to end as a year that will be rated as one of the three warmest ever recorded. The past six years, 2015 to 2020, are set to make up all six of the hottest years since modern records began in 1850. 2020 has become synonymous with apocalyptic fires and floods, cyclones and hurricanes. The UN Secretary General has correctly pointed out that humanity is waging war on nature. This is suicidal. Nature always strikes back and it is already doing so with growing force and fury.
Temperature averages across the last five years and across the last 10-year period are the warmest on record and this is testament to the acceleration of global warming. The average global temperature in 2020 is set to be about 1.2 C above the pre-industrial level as there is at least a one in five chance of it temporarily exceeding 1.5 C by 2024. In its first seven months, 2020 remained the second-warmest year on the books, a mere 0.07 degree Fahrenheit behind 2016 at the same point as pointed out by National Oceanic and Atmospheric Administration whose records go back 141 years.
One of this 2020’s notable hotspots has been Siberia which has been covered by an angry, deep-red blotch on global temperature maps. The region has been exceptionally hot since the beginning of the year, contributing to this past January being the planet’s warmest on record. More recently the Siberian town of Verkhoyansk reported 100.4 degrees F and it is reported to be first time that temperatures above the Arctic Circle have surpassed 100 degrees F. But this hotspot is not the sole reason that 2020 is near the top of the charts. Above-average temperatures have been prevalent over large swaths of the globe. Asia, South America and Europe all had record-warm temperatures.
Crucially, global oceans also continued to get warmer. Oceans serve as a good indicator of the real impact of climate change. Covering almost three quarters of Earth’s surface, they absorb the vast majority of the world’s heat and in 2020 more than 80% of the global oceans experienced a marine heatwave at some time. The effects of this rapid warming have been felt around the world throughout the year — from extreme heat and wildfires to floods and a record-breaking Atlantic hurricane season. Millions of people have been forced to leave their homes — some of them permanently — because of extreme weather and other events caused or exasperated by climate change. Hundreds have died.
Broad areas of warmth and more localised hotspots are both linked to the long-term warming trend. It has reached a point where these intense heat waves would not be possible in any reasonable amount of time in a non-human-perturbed climate. A recent analysis of the role of global warming in Siberia’s prolonged heat found that such extremes would happen around once every 80,000 years in the absence of anthropogenic warming. These extremes are also happening over larger areas than they would in the absence of climate change.
2020 also brought some unusually strong heat-waves — most notably across northern Asia, particularly the Siberian Arctic. In parts of northern Siberia, the year to date has been 5 degrees Celsius or more warmer than average. South America and much of Europe also experienced heat-waves and prolonged droughts. A number of temperature records fell this year. When the mercury reached 54.4 degrees Celsius in California’s Death Valley in August, it was the highest known temperature in the world in at least the last 80 years. And while some parts of the world experienced heat-waves and drought, other areas suffered deadly flooding causing more than 2,000 during the flood season in India, Pakistan, Nepal, Bangladesh, Afghanistan and Myanmar.
Worryingly, 2020 has been unusually hot despite the cooling effect of La Niña. The recurrent climate phenomenon which developed in August and strengthened in October is normally associated with below-normal sea surface temperatures in the Pacific Ocean caused by changes in winds, air pressure and rainfall. While La Niña is limited to the Pacific, its effects act to cool the entire planet’s temperatures like natural air conditioning for Earth. But its impact has been more than offset by heat trapped in the atmosphere by greenhouse gasses. Massive wildfires that devastated vast areas in Australia, Siberia, the US West Coast and South America in 2020 have been tied to climate change. Meanwhile a record 30 named storms, including 13 hurricanes, formed in the Atlantic Ocean, exhausting the alphabet and forcing a switch to the Greek alphabet for only the second time ever.
Late last year and early this year, Australia suffered what was the worst bushfire season on record. The climate crisis made those fires at least 30% more likely. At least 33 people and an estimates one billion animals perished in the fires. Devastating wildfires in the western US left at least 43 people dead this fall. In October, California recorded the first “giga-fire” — a term for a blaze that burns at least a million acres of land — in modern history. South American Pantanal, world’s largest tropical wetlands was on fire for months. This year also brought plenty of evidence for a trend climate scientists have been warning about for some time: hurricanes, typhoons and tropical cyclones worldwide. The number of tropical cyclones globally was above average in 2020. The north Atlantic hurricane season had its largest number of named storms on record. Many caused death and devastation. In the Philippines, dozens of people died when two one-after-the-other Typhoons hit within 10 days of each other in November.
The core highlighted area is the Arctic that is undergoing drastic changes as the global temperature increases. In September, the amount of Arctic sea ice shrunk to the second lowest level since records began in 1878. The Greenland ice sheet has continued to lose mass, although at a slower rate than seen in 2019. The ice cover plays a key role in regulating global climate. Its bright surface reflects heat back to the atmosphere. When it melts or does not refreeze, the darker ocean surface absorbs more heat.
Because of global warming, the earth’s baseline temperature has shifted so much higher that 1998 is now being left in the dust. No matter where 2020 ends up in the standings, it will be warm enough to knock 1998 out of NOAA’s top 10. When that happens, all of the 10 warmest years in their records will have occurred since 2005 and the top seven will have occurred since 2014. That bunching of heat records in more recent years is, again, because of long-term warming, which is stacking the deck for ever more frequent records. It is noted that between the late 19th century and 1980, new records for the hottest year would happen about every eight to 11 years. Since 1981, they have been occurring about every three to four years. So if 2020 takes the top slot, it will not be entirely unexpected and will be yet another stark example of how far the earth’s climate has deviated from its natural course. TW