Globally, November 2020 was the warmest November on record, by a clear margin. For Europe, the month was the joint second warmest on record. Temperatures were most above the 1981-2010 average over a large region covering much of northern Europe, Siberia and the Arctic Ocean, while temperatures were most below average over central Asia and West Antarctica.

November 2020 was warmer than the 1981-2010 average for the month over almost all of  Europe. Temperatures were considerably higher than average over the Alps and the north of the continent. Norway had its joint warmest November in a data series reaching back to 1900. Sweden and Finland also saw records broken. Conditions were close to or a little cooler than average only in parts of the south-east of the continent.

Temperatures were exceptionally high for November over a large region covering much of Siberia, the Arctic Ocean and bordering coastal seas, extending into western and northern Alaska and the far north-west of Canada. Temperatures were also substantially higher than average over the Tibetan Plateau and East Antarctica.

Heatwaves were experienced in parts of Australia during November 2020, and the month was the warmest November on record for the country as a whole. Heatwaves were also reported in Malawi and Mozambique, and it was generally warmer than average over much of southern, central and western Africa. Temperatures were also several degrees higher than normal east of the Andes, over a region stretching from Peru to Patagonia. Most of the USA and southern Canada was significantly milder than usual for late autumn, with many local temperature records broken in the central and eastern regions. Florida, New Mexico and Arizona experienced unusually high temperatures, states for which the January-to-October average temperatures for 2020 were the highest on record.

Temperatures were below average over a region extending from the Central Asian Republics to Pakistan and northern India, by more than 5°C west of Lake Balkhash in Kazakhstan. It was also colder than usual by a similar amount over West Antartica. Temperatures were also below average over parts of Canada, Greenland and North Africa, and over coastal Brazil and the far south-west of Australia.

Air temperatures remained relatively high over the North Pacific Ocean and off the eastern seaboard of North America. Marine air temperatures were also well above average east of Argentina, and also above average over most of the Indian Ocean, the western Pacific and around most of Australia. Relatively cool La Niña conditions persisted  over the tropical eastern Pacific, and temperatures were below average in several places over the extratropical oceans of the Southern Hemisphere and over part of the North Atlantic. 

Global-mean temperatures were substantially above average in November  2020. The month was:

  • 0.77°C warmer than the 1981-2010 average for November
  • the  warmest November in this data record by a clear margin
  • 0.13°C warmer than the previous warmest Novembers, which were in 2016 and 2019.
  • November 2020 was also the joint fourth most extreme month of any in terms of global warmth compared with the climatogical average for the month in question. Its temperature anomaly was on a par with that of January 2020. Only February and March 2016 and February 2020 were more extreme, with temperatures respectively 0.88°C, 0.82°C and 0.80°C above average.

European-average temperature anomalies are generally larger and more variable than global anomalies. The European-average temperature for November 2020 was: 

  • the joint second highest on record for November
  • 2.2°C above the 1981-2010 average
  • 0.2°C below the temperature for November 2015
  • similar to the temperature for November 2009

Boreal autumn temperatures were most above average over northern Siberia, the Arctic Ocean and neighbouring coastal seas, particularly in a region extending eastward from Svalbard over the seas north of Siberia to the Beaufort Sea north of Alaska. They were much above average over most of the rest of Siberia, over the Tibetan Plateau, and in a band stretching from the Middle East to northern Europe. The remainder of Europe was also generally warmer than average.  Conditions were relatively warm over the western and south-eastern USA and over the north-west of Africa.  Marine air temperatures were unusually high over the North Pacific and western North Atlantic. The season was colder than average over much of Canada and parts of Greenland, central Asia and southern China.

The Austral spring saw warmer-than-average conditions over most of South America, southern Africa and Australia. Temperatures were much above average over East Antarctica but a little below average over West Antarctica. Air temperatures were below average in a zone along the equatorial eastern Pacific associated with a La Niña event. Below average temperatures extended over the south-eastern Pacific Ocean.  

The September-November average temperature for Europe was the highest on record. It was 1.9°C above the 1981-2010 norm, 0.4°C higher than the average temperature for 2006, the previous warmest autumn.

Temperatures averaged over the twelve-month period from December 2019 to November 2020 were:

  • most above the 1981-2010 average over a large part of Siberia, and the Arctic Ocean to the north of Siberia and Alaska
  • above average over virtually all of Europe, more so in the north and east
  • above average over most other areas of land and ocean
  • below average over a few land areas, particularly parts of western Canada and northern India
  • below average over the eastern equatorial Pacific, the North Atlantic west of Ireland and several oceanic areas in the Southern Hemisphere.

Averaging over twelve-month periods smooths out shorter-term variations in regional- and global-average temperatures. Globally, the twelve-month period from December 2019 to November 2020 was 0.65°C warmer than the 1981-2010 average. The temperature for this period is less than 0.01°C below that of the 12-month periods ending in May 2020 and September 2016, the two warmest periods in this record. 2016 is the warmest calendar year on record, with a global temperature 0.63°C above that for 1981-2010. For the year-to-date (January to November) the average 2016 and 2020 temperatures are on a par. As December 2016 had a much smaller temperature anomaly than November 2020, it would take a large but not unprecedented fall in temperature anomaly from November to December 2020 for the calendar year of 2020 not to be similar to or even marginally warmer than 2016. 2019 is currently the second warmest complete calendar year in this data record; its temperature is 0.59°C above average.

0.63°C should be added to these values to relate recent global temperatures to the pre-industrial level defined in the IPCC Special Report on “Global Warming of 1.5°C”. The average temperature for the twelve months to November 2020 is nearly 1.3°C above that level. 

There is more variability in average European temperatures, but values are more certain due to the relatively dense observational coverage of the continent. The latest twelve-month average, to November 2020, is 1.7°C above the 1981-2010 average, the highest on record. The warmest calendar year on record for Europe was 2019, though by only a narrow margin to 2015, 2014 and 2018. Its average temperature was 1.2°C above the 1981-2010 average. For the year-to-date, 2020 is 0.5°C warmer than 2019 and at least 0.4°C warmer than any other such period in the data set. It is almost certain that 2020 will become the warmest calendar year for Europe as a whole.

Note on global values from ERA5 and other temperature datasets

The spread in global averages from various temperature datasets has been relatively large over the past four years. For this period, the twelve-month-average temperatures relative to 1981-2010 presented here are higher than those from five other datasets, by between 0.03°C and 0.14°C, with median 0.06°C, for the year 2019. This is due partly to differences in the extent to which datasets represent the relatively warm conditions that have predominated over the Arctic and the seas around Antarctica. Differences in estimates both of sea-surface temperature elsewhere and of temperatures over land in general have been further factors. An additional small difference is that the global values presented here are derived from estimates of air temperature over sea, which have risen slightly faster than the sea-surface temperatures used by four of the other datasets.

There is nevertheless general agreement between the datasets regarding:

  • the exceptional warmth of the period since 2015
  • the general increase in global temperature at an average rate close to 0.2°C per decade since the late 1970s
  • the sustained period of above-average temperatures from 2002 onwards.

The average surface air temperature analysis homepage explains more about the production and reliability of the values presented here. 

The ERA5 temperature dataset used here differs from several other datasets in that it has a cooling trend to the north and north-east of Greenland. This trend is associated with positive (warm) wintertime temperature anomalies in the first ten or so years of the 1981-2010 reference period. These anomalous temperatures may be linked with questionably low values of the fractional sea-ice cover specified in ERA5 at that time. As a result, cold anomalies in recent winter months (and annual averages) over this region must be viewed with caution.

November 2020 was characterised by lower than average pressure near the North Pole and higher than average pressure in middle latitudes, with a maximum over central Europe. The associated winds were stronger and more from the south than usual over Scandinavia, and westerlies were stronger than usual over the ice-free Barents and Kara seas. Both the anomalous flow and route over seas that in years past would have been ice-covered are factors favouring warmer than usual conditions over northern Europe and Asia, and the Arctic Ocean.

November 2020

Source: https://climate.copernicus.eu/surface-air-temperature-november-2020

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