The global temperature was 1.21 degrees Celsius (2.18 degrees Fahrenheit) above the 20th century average, 0.09 degrees C above the previous highest departure in December 2015, NOAA said.
“The departures are what we would consider astronomical,” NOAA climate scientist Jessica Blunden told the Associated Press.
Remarkably, the six highest monthly temperature departures on record for the planet have all occurred in the last six months.
In February, NOAA said temperatures over “a vast region stretching from central Russia into eastern Europe, along with most of Alaska” recorded temperatures at least 5 degrees Celsius (9 degrees Fahrenheit) higher than average, “above the upper bounds” of its map (see dark reds in top image).
Averaged over the globe, recent months mark an unprecedented warm period in modern history.
The December-February period was, by far, warmest on record:
The start to the current calendar year is at another level compared to years of the past:
Indicators of snow and ice in February independently support the exceptional warmth recorded by ground-based measurements.
Arctic sea ice extent was at its lowest level on record in February:
While the time series shows lots of fluctuation, Northern Hemisphere snow extent fell to its lowest level in 14 years:
The extraordinary global warmth in recent months was set in motion by the long-term climate-warming trend, but surged to another level because of the record-challenging El Niño event that released into the atmosphere large quantities of heat stored in the tropical Pacific Ocean.
While the warming pressure from anthropogenic emissions of greenhouse gases will continue indefinitely, the relentless string of monthly temperature records is likely to end as the El Nino event wanes later this year.
Greenhouse gas emissions push the long-term temperature trend upwards, but shorter term, cyclical features like El Nino lead to the spikes in temperature that cause records. When El Nino fades away, while temperatures will steadily move towards a higher baseline, it may be some time before the kind of record spikes we’ve witnessed recently occur again.