Snow cover over Spain and France from data acquired by MODIS on NASA’s Aqua satellite on January 11th 2021. Image courtesy of NASA Earth Observatory’s Lauren Dauphin, using MODIS data from NASA EOSDIS LANCE and GIBS/Worldview.
This is not a warning, but an oxymoron for two key weather stories over the last week.
Firstly, the Copernicus Climate Change Service (C3S) announced that 2020 was the planet’s joint warmest year on record – tied with 2016. It was also was the sixth consecutive year with temperatures above the long-term average, with 2020 being 0.6°C warmer than the standard 1981-2010 reference period and 1.25°C above the 1850-1900 pre-industrial period.
To be completely accurate, C3S indicated that 2106 was ever so slightly warmer than last year, however, statistically, the differences meant that both years were classed as having the same temperature. Even accepting that 2016 is slightly warmer, the outcome is surprising for 2020 given each year’s position in the El Niño/La Niña weather cycle. 2016 being made warmer by a strong El Niño event, whilst 2020 was made cooler due to a La Niña event in the latter half of the year.
C3S uses data from the fleet of Sentinel satellites to gather information about the world’s climate and as this suite collects a range of optical and radar data it allows a variety of measurements to be made. Last week’s report also noted that:
- The largest annual temperature deviation from the 1981-2010 average was concentrated over the Arctic and northern Siberia. Some areas reached over 6°C above average with large parts of the area seeing a 3°C deviation, meaning that this was a key element of the overall global increase.
- Arctic sea ice was significantly lower than average for the time of the year with July and October seeing the lowest sea ice extent on record for the respective month.
- CO2 global column-averaged maximum reached 413 parts per million (ppm) during May and the year’s annual growth was 2.3 ± 0.4 ppm. This is slightly below the previous year’s growth rate – this in itself is interesting given the slowdown in industrial output during the year in various countries with the global pandemic.
- Wildfire season was very active during 2020 with first fires detected in May, and going all the way through to the autumn – which also contributed to the CO2 increase.
According to C3S, 2020 was also Europe’s warmest year on record; however, 2021 has kicked off with a spell of much colder weather with the heaviest snowfall over Spain in fifty years. Storm Filomena hit the country last weekend depositing up to 50 centimetres of snow in the central, northern and eastern areas. The capital, Madrid, saw up to 30 centimetres of snow the first time in ten years it has had significant snowfall which led to almost 700 roads becoming impassable and cancelling most rail and air travel for two days.
The impact of the snow can be seen in the image at the top of the blog, which shows northern Spain and southwestern France landscape turning white with the snow cover. The image is from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite which was acquired on January 11th 2021.
Spain is expecting the freezing temperatures to last until the end of this week, meaning that weather-wise 2021 already has things to talk about.
