When we talk about climate change, there is definitely an air of doom and gloom about the stories. We hear rumblings in the scientific community of how close we are getting to a tipping point from which the climate may never recover, but new research published in Geophysical Research Letters suggests that the climate may be more resilient than previously understood.

If you live in the Pacific Northwest here in the U.S., you are likely familiar with the Columbia River Basalt Group. It’s an area of basaltic flood rock that basically takes up much of Washington and Oregon. And we mean… much. For context, take the ongoing eruption of Kīlauea and have it last for millions of years rather than decades, on and off, almost constantly. And then punctuate that long-term eruption with some large explosive ones, similar to the Hunga Tonga-Hunga Ha’apai eruption earlier this year.

Again, have this keep going for millions of years. Flood the region with 210,000 square kilometers of basalt, and you have the Columbia River Flood Basalt event.

On top of all that lava rock being deposited, the ongoing eruptions also released about 300 gigatons of sulfur dioxide, and that is a greenhouse gas which means hello, climate change! Of course, the eruptions also release carbon dioxide, another greenhouse gas, but analysis of the rocks in the Columbia River region show that the carbon dioxide levels weren’t enough to produce the kind of climate change also seen in the rock record.

And that’s why this particular paper looked at sulfur dioxide. The researchers wanted to understand just what type of effect that particular gas had on the global climate, and the results were about what you would expect. Now, we report these results with the caveat that because the team was using computer models and a lot of processing power, they were only able to model an eruption period of four years and track the climate response for a further sixteen years.

Even with that brief duration, the effects were pretty massive. Global temperatures dropped by 2 to 3 degrees Celsius on average, and seasonal temperature effects were larger – the Northern Hemisphere saw summer temps drop by 30 degrees Celsius and winter temps increased by 15 degrees. The sulfur dioxide rose up into the atmosphere and essentially created an umbrella effect that kept the Sun’s heat out and temporarily destroyed the tropopause. Additionally, the ozone layer was wiped out.

So where is the good news in all this doom and gloom? The researchers found that, after sixteen years, the climate had completely rebounded. Temperatures returned to normal levels, the humidity dropped back to pre-existing levels, and the ozone layer recovered. The catch here, though, is that the actual eruption lasted far, far longer, and it’s associated with two different extinction events.

Yes, the climate itself will recover. But we may not. Lead author Scott Guzewich notes: Even with as massive of a perturbation to the climate as this produces, the climate gets back to normal surprisingly quickly. If you’re thinking about a disaster on Earth in modern times, it shows that the climate is somewhat resilient, that even this large of an effect doesn’t push Earth past a tipping point.

The news isn’t all bad, but it’s not all good, either.

More Information

The Surprising Greenhouse Gas That Caused Volcanic Summer (Eos)

“Volcanic Climate Warming Through Radiative and Dynamical Feedbacks of SO2 Emissions,” Scott D. Guzewich et al., 2022 February 1, Geophysical Research Letters