` Megadrought May Be Underway in American West, Researchers Say - Olive Oil Times

Megadrought May Be Underway in American West, Researchers Say

Apr. 22, 2020
Isabel Putinja

Recent News

A new study has revealed that con­di­tions that began in the Southwestern United States and Mexico in 2000 could be lead­ing to a megadrought.

We now have enough obser­va­tions of cur­rent drought and tree-ring records of past drought to say that we’re on the same tra­jec­tory as the worst pre­his­toric droughts- Park Williams, Columbia University

The study, pub­lished in the jour­nal Science last week, warns that ris­ing tem­per­a­tures due to cli­mate change are ampli­fy­ing what would have been a mod­er­ate drought affect­ing the Southwestern states and north­ern Mexico. With the con­tin­u­ing trend of global warm­ing, it can evolve into a megadrought — a pro­longed, extreme drought that lasts longer than two decades.

See more: Climate Change News

According to the researchers, the emerg­ing megadrought had its begin­nings twenty years ago. As part of the study, the researchers used hydro­log­i­cal mod­el­ing to pre­dict water resources and exam­ined thou­sands of 1,200-year tree ring recon­struc­tions and records of sum­mer soil mois­ture to col­lect data on cli­mate con­di­tions of the past.

The analy­sis revealed that the period from 2000 to 2018 was the dri­est in the Southwest since the late 14th cen­tury and the sec­ond dri­est since 800 CE.

Earlier stud­ies were largely model pro­jec­tions of the future,” said Park Williams, a bio­cli­ma­tol­o­gist at Columbia University’s Lamont-Doherty Earth Observatory and the lead researcher of the study.

We’re no longer look­ing at pro­jec­tions, but at where we are now. We now have enough obser­va­tions of cur­rent drought and tree-ring records of past drought to say that we’re on the same tra­jec­tory as the worst pre­his­toric droughts,” he said in a state­ment pub­lished by the Observatory.

The study looked at a geo­graph­i­cal area span­ning nine US states from Oregon to Montana and through California, New Mexico and a part of north­ern Mexico.

The reper­cus­sions of the pro­longed drought con­di­tions have been notice­able in recent years, with water lev­els at the Lake Mead and Lake Powell reser­voirs at low lev­els, the grow­ing inci­dence of wild­fires in the Southwestern U.S., and pro­longed droughts in California which have had a neg­a­tive impact on agri­cul­ture.

With tem­per­a­tures pro­jected to con­tinue ris­ing in the face of cli­mate change, sci­en­tists pre­dict that the drought con­di­tions are likely to con­tinue.

It doesn’t mat­ter if this is exactly the worst drought ever,” said Benjamin Cook, a cli­mate sci­en­tist at the Lamont-Doherty Earth Observatory and co-author of the study. What mat­ters is that it has been made much worse than it would have been because of cli­mate change.”

Because the back­ground is get­ting warmer, the dice are increas­ingly loaded toward longer and more severe droughts,” added Williams. We may get lucky, and nat­ural vari­abil­ity will bring more pre­cip­i­ta­tion for a while. But going for­ward, we’ll need more and more good luck to break out of drought, and less and less bad luck to go back into drought.”


Related News

Feedback / Suggestions