Sometimes a simple tweet on a Sunday evening can go a long way.
This summer’s persistent dry and warm weather in the UK has led to many comparisons to the summer of 1976, which saw a lethal combination of the warmest June-August mean maximum temperatures (per the Met Office record stretching back to 1910) and a record-breaking lack of rainfall (a measly 104.6 mm – since bested by 1995’s 103.0 mm – compared with the record-wettest 384.4 mm in 1912). When combined with a hot summer the year before and a dry winter, water shortages were historic and the summer has become a benchmark to which all UK heatwaves are compared. So far, 2018 has set a new record for the driest first half of summer for the UK (a record stretching back to 1961) but it remains to be seen whether it will truly rival ’76.
All these comparisons made me wonder: what did global temperatures look like during the heatwave of 1976? Headlines have been filled with news of other heatwaves across the Northern Hemisphere, including in Africa, Finland and Japan. Was the UK heatwave in 1976 also part of a generally warm pattern?
So I had a look at the data using the plotting tool available on NASA’s Goddard Institute for Space Studies (GISS) site, and composed a relatively simple tweet which took off in a manner only fitting for a planet undergoing rapid warming:
The big difference between the heatwaves of 1976 and 2018.
June 1976: the UK was one of the warmest places relative to normal across the globe, with most areas cooler than average.
June 2018: the UK was just another warm blob in a mostly warmer than normal world.#GlobalHeatwave. pic.twitter.com/eIsj7glEiE
— Simon Lee (@SimonLeeWx) July 22, 2018
At the time of writing, it’s been retweeted over 8,800 times in under 48 hours and featured as part of a Twitter Moment. Even Héctor Bellerín, a footballer for Arsenal, retweeted it!
Imagine there’s still people who believe global warming is not a real problem for us 😭 https://t.co/auz4ZvC3aR
— Héctor Bellerín (@HectorBellerin) July 24, 2018
Once the tweet had taken on a life of its own, I was also well aware of so-called “climate change deniers” (I don’t like the term, but it’s the best I can do) lurking out there, and I was somewhat apprehensive of what might get said. I’ve seen Paul Williams have many not-so-pleasant Twitter encounters on the subject of climate change. However, I was actually quite surprised. Aside from a few comments here and there from ‘deniers’ (usually focusing on fundamental misunderstandings of averaging periods and the interpolation used by NASA to deal with areas of low data coverage), the response was generally positive. People were shocked, frightened, moved…and thankful to have perhaps finally grasped what global warming meant.
I endeavoured to keep it cordial and scientific, as the issue is too big to make enemies over – we all need to work together to tackle the problem.
To put this into a long-term global context, here’s how June has warmed since @NASAGISS data begins in 1880. I’ve highlighted 1976 and 2018. Lots of variability, but a steep, persistent and, fundamentally, *undeniable* warming. pic.twitter.com/LZdlpMh3eU
— Simon Lee (@SimonLeeWx) July 23, 2018
So, maybe now I have some idea how Ed Hawkins felt when his global warming spiral went viral and eventually ended up in the 2016 Olympics opening ceremony. I guess the biggest realisation for me is that, as a scientist, I’m familiar with graphics such as these showing the extent of global warming, but the wider public clearly aren’t – and that’s part of the reason I believe the tweet became so popular.
I can’t say that the 2018 UK heatwave is due to global warming. However, with unusually high temperatures present across the globe, it takes less significant weather patterns to produce significant heatwaves in the UK (and elsewhere). And with the jet streams that guide our weather systems already feeling the effects of climate change (something which I researched as an undergraduate), we can only expect more extremes in the future.