Climate change in itself has a big impact on the world and whether you agree with that or not doesn’t really matter. This ‘megadrought’ by some is thought to have started in the year 2000 and still be underway but others are not so convinced and believe it is too early to claim such an occurrence.

Researchers published a paper in recent times covering this whole ordeal as best they could and it notes periods of high severity that have lasted longer than anything observed during some of the more recent previous centuries. Their study was titled ‘Large contributions from anthropogenic warming to an emerging North American megadrought’. According to BBC, these researchers used tree ring records to reconstruct soil moisture data from over the past 1200 years or so. 

The abstract of this study goes as follows:

Severe and persistent 21st-century drought in southwestern North America (SWNA) motivates comparisons to medieval megadroughts and questions about the role of anthropogenic climate change. We use hydrological modeling and new 1200-year tree-ring reconstructions of summer soil moisture to demonstrate that the 2000–2018 SWNA drought was the second driest 19-year period since 800 CE, exceeded only by a late-1500s megadrought. The megadrought-like trajectory of 2000–2018 soil moisture was driven by natural variability superimposed on drying due to anthropogenic warming. Anthropogenic trends in temperature, relative humidity, and precipitation estimated from 31 climate models account for 47% (model interquartiles of 35 to 105%) of the 2000–2018 drought severity, pushing an otherwise moderate drought onto a trajectory comparable to the worst SWNA megadroughts since 800 CE.

When comparing the data they gained and drought events overall these researchers seemed to find that the current period we’re facing is already worse than three of the four megadroughts that have been recorded previously. While you may still be seeing rain some where you are, there are places that are not getting much at all and as a whole, we’re seeing some big differences.

The BBC reported as follows about whether this was a natural event or climate change caused:

The authors say that undoubtedly the current drought situation is a natural event but is being made much worse by climate change.

The key event seems to have been the El Niño/La Niña weather phenomenon.

“We know from, from many lines of evidence that when you have La Niña type conditions in the tropical Pacific Ocean, then the southwestern US and northern Mexico get dry. And that’s what we’ve seen over the last two decades,” said Dr. Williams.

But climate change has super-charged the current drought.

The authors say that in the western US, temperatures have gone up by 1.2C since 2000. Hotter air holds more moisture and that moisture is being pulled out of the ground.

They believe that climate change is responsible for about half of the pace and severity of the current event.

“It doesn’t matter if this is exactly the worst drought ever,” said co-author Benjamin Cook, who is affiliated with Columbia University and Nasa’s Goddard Institute for Space Studies.

“What matters is that it has been made much worse than it would have been because of climate change.”

What do you think about all of this? Do you think these researchers are correct in their findings? I for one am quite blown away. To learn more about this topic please check out the video below.

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