March 2021 was the eighth-warmest March since global record-keeping began in 1880, 0.85 degrees Celsius (1.53°F) above the 20th-century average, NOAA’s National Centers for Environmental Information, NCEI, reported April 13. NASA also rated March 2021 as the eighth warmest March on record.
While it was the eighth-warmest March since 1880, March 2021 was Earth’s coolest March since 2014, according to the European Copernicus Climate Change Service and NOAA. The relative coolness was partially the result of a weakening La Niña event in the Eastern Pacific: Its cool waters helped depress global surface temperatures.
The year-to-date period January-March ranked as Earth’s ninth-warmest such period on record. According to NCEI’s annual temperature outlook, the year 2021 is more than 99% likely to rank among the 10 warmest years on record, and 95% likely to fall in the range of fourth- to ninth-warmest on record. The NCEI outlook finds that 2021 has a less than 1% chance of becoming the warmest year on record, reflecting the modest cooling influence of the La Niña event in the Eastern Pacific.
Global ocean temperatures during March 2021 were the ninth-warmest on record, as were global land temperatures for the month. Global satellite-measured temperatures in March 2021 for the lowest eight kilometers of the atmosphere were the 11th-warmest in the 43-year record, according to Remote Sensing Solutions.
March 2021: 14th-warmest March on record in the U.S.
The U.S. experienced its fourteenth-warmest March since records began in 1895, with seven states in the north-central U.S. experiencing a top-10 warmest March, according to NOAA. The year-to-date period January-March ranked in the top 25% for warmth, historically.
March 2021 precipitation over the contiguous U.S. was near average, but had wide disparities. Montana and North Dakota recorded a top-5 driest March on record; Nebraska, Kansas, and Tennessee recorded a top-5 wettest March. According to the U.S. Drought Monitor, approximately 45% of the contiguous U.S. was in drought on April 8. Since the Drought Monitor was established in 2000, only one April has had higher drought coverage – April 2013, with 52%.
The 12-month period ending March 2021 was the driest on record for most of the southwestern U.S., and the latest seasonal drought forecast from NOAA calls for drought to expand eastwards over much of the central U.S. by June. Drought is likely to be a multi-billion dollar U.S. weather disaster in 2021.
One billion-dollar weather disaster in March; five so far in 2021
One billion-dollar weather disaster affected Earth in March 2021: flooding in southeastern Australia that cost $2 billion, according to insurance broker Aon. Through the end of March, Earth had experienced five billion-dollar weather disasters, Aon reported:
1. Winter weather, U.S., Feb. 12-20, $20 billion, 147 killed;
2. Flooding, Southeastern Australia, Mar. 10-24, $2 billion, 2 killed;
3. Winter storm Filomena, Spain, Jan. 8-12, $1.8 billion, four killed;
4. Flooding, Western U.S., Jan. 24-29, $1.5 billion, two killed; and
5. Winter weather, Japan, Jan. 7-12, $1.25 billion, 23 killed.
La Niña expected to transition to neutral by summer
Weak La Niña conditions remained in place during March 2021, and NOAA continued its La Niña advisory in an April 8 monthly discussion of the state of the El Niño/Southern Oscillation, or ENSO. The Australian Bureau of Meteorology, which uses a more stringent threshold than NOAA for defining La Niña, reported that the 2020-2021 La Niña event ended in March.
Over the past month, sea surface temperatures in the benchmark Niño 3.4 region of the eastern tropical Pacific (5°N-5°S, 170°W-120°W) have averaged about 0.3 degrees Celsius below average, falling in the “neutral” range. The range for “weak” La Niña conditions is 0.5-1.0 degrees below average. However, the three-month average sea surface temperatures for January-March in this region still met the La Niña criterion.
Forecasters at NOAA and at Columbia University’s International Research Institute for Climate and Society expect La Niña conditions to transition to “neutral” for the May-July period (80% chance). The forecast for the fall (September-October-November) is for a 40-50% chance of La Niña, 40-50% chance of ENSO-Neutral, and a low chance of El Niño. Historically, about half of all La Niña events have continued into a second year.
Arctic sea ice: ninth-lowest March extent on record
Arctic sea ice extent during March 2021 was the ninth-lowest in the 43-year satellite record, according to the National Snow and Ice Data Center. Arctic sea ice extent reached its annual maximum on March 21, and was the seventh lowest in the 43-year satellite record.
Antarctic sea ice extent during March was above average.
Notable global heat and cold marks for March 2021
All of the information below is courtesy of Maximiliano Herrera. Follow him on Twitter: @extremetemps.
– Hottest temperature in the Northern Hemisphere: 46.7°C (116.1°F) at Tamuin, Mexico, March 24;
– Coldest temperature in the Northern Hemisphere: -64.1°C (-83.4°F) at Summit, Greenland, March 25;
– Hottest temperature in the Southern Hemisphere: 44.2°C (111.6°F) at Addo, South Africa, March 13;
– Coldest temperature in the Southern Hemisphere: -70.3°C (-94.5°F) at Concordia, Antarctica, March 20;
– Highest 2021 average temperature to date (Jan. 1-Mar. 31) worldwide: 31.9°C (89.4°F) at Marble Bar, Australia; and
– Highest 2021 average temperature to date (Jan. 1-Mar. 31) in the Northern Hemisphere: 31.5°C (88.7°F) at Kenieba, Mali.
Major weather stations’ new all-time heat or cold records in March 2021
Among global stations with a record of at least 40 years, one set, not just tied, a new all-time heat record in March. No stations set all-time cold records:
– East London (South Africa) max. 44°C, March 13.
One all-time national/territorial cold record set or tied in 2021
As of March 31, 2021, one nation or territory had set or tied an all-time national cold record:
United Arab Emirates (for places at low elevations): -2.0°C (28.4°F) at Raknah, January 9.
No all-time national/territorial heat records have been set thus far in 2021.
Thirty-six monthly national/territorial heat records beaten or tied as of March 31
– January (10): Mexico, Bangladesh, Nigeria, Japan, Malta, Tunisia, Turkey, Russia, Georgia, Spain
– February (12): Iraq, Uzbekistan, Mongolia, South Korea, Liechtenstein, Slovenia, Croatia, Slovakia, Poland, Sweden, Pakistan, Northern Mariana Islands
– March (14): Northern Mariana Islands, Qatar, Saudi Arabia, Bahrain, Kuwait, Pakistan, Oman, Jersey, Guernsey, Germany, Netherlands, Luxembourg, Belgium, US Virgin Islands
No national/territorial monthly cold records in addition to the one all-time national record in the UAE mentioned above have been set thus far in 2021.
Hemispherical and continental temperature records in 2021
Jeff Masters is now active on Twitter; follow him at @DrJeffMasters