Climate change doubters claim that computer simulations that predicted climate change a few decades ago were inaccurate. Because of this, they also conclude that the public shouldn't listen to current simulation models either.
However, these doubters' stance may have just been knocked over as a recent evaluation of these older models shows they were, in fact, accurate.
The study's findings were published in Geophysical Research Letters on Wednesday 4, December.
Models were right in their predictions
Lead author of the study, Zeke Hausfather a graduate student from the University of California, Berkeley, said "How much warming we are having today is pretty much right on where models have predicted."
After a year of work our paper on evaluating performance of historical climate models is finally out! We found that 14 of 17 the climate projections released between 1970 and 2001 effectively matched observations after they were published. https://t.co/xbmOh4ZPcn 1/19 pic.twitter.com/xjez5FWwd3— Zeke Hausfather (@hausfath) December 4, 2019
Climate scientists have used computer simulations to predict global warming since the 1970s. At the time, these computers were a new addition to society and not always fully trusted for their accuracy.
Nowadays, newer models are much more sophisticated. They can account for a number of interactions at the same time: ice and snow, changes in forest formations, as well as cloud movements. This was a pipedream back in the 1970s.
Hausfather and his team wanted to see just how accurate these older models were.
Its also worth mentioning that there were some non-peer-reviewed projections, such as this one from Exxon researchers in the early 1980s, that also performed well but were not included in our paper (as they were not academic publications): https://t.co/lustKVYuLZ 20/19 pic.twitter.com/hZTwYwjxZ4— Zeke Hausfather (@hausfath) December 4, 2019
It turns out that most of the models in fact accurately predicted the global rise in temperatures, which has risen by around 0.9 degrees Celcius (33 degrees Fahrenheit).
The team's new findings underline what many in the world of climate change already knew. However, it's good "to have it confirmed", as Piers Forster, an expert in climate modeling at the University of Leeds, in the U.K., said.
Former NASA scientist, James Hansen, added that having this understanding of past computer simulation systems "should provide some confidence that models can be used to help provide guidance regarding energy policies."
This research shows the accuracy from the past, and also helps to prove our current simulation models' accuracy.