The economy’s big fear was a simultaneous global drought. Science has found our lifesaver

We have been observing for years how climatic extremes They hit different parts of the globe, with the experience in Spain still very marked. But with him increase in temperatures To the extreme, one of the biggest fears of climatologists and economists is the synchrony of global droughts. That is, a scenario in which the main food-producing regions dry out at the same time. The good news is that science indicates that the Earth (at the moment) is not drying out.

A problem. Logically, if the main countries in the world where wheat, rice, corn or soybeans are produced had a drought simultaneously, we would have a huge problem of product supplywhich for many is a real nightmare.

But here the researchers have reached a conclusion: synchronized global droughts are severely limited and barely affect between 1.8% and 6.5% of the global land surface at the same time. Without a doubt, a great respite for economists who saw the end of the world as we know it and who has been published in Nature. But the most impressive thing is that all this is thanks to the oceans.

What we knew. Until now, we knew that major climate events such as The Child wave North Atlantic Oscillationcould alter rainfall patterns thousands of miles away through what scientists call “teleconnections.” And it is something that the research team itself pointed out in the past: there are interconnected drought nodes at different latitudes, most in North America, South America, Africa and Australia. That is, when there is drought in one place, it can move to another.

But, if these nodes are connected… Why doesn’t the entire planet dry out at once when there is an anomaly like El Niño? The answer is in the oceanic variability.

An ally. In this case, the oceans act as an immense regulatory mechanism and that is why the authors literally speak of a phenomenon called ‘geographic trapping’. In this way, the dynamics of the oceans force the scale of these hydrological extremes to remain confined to certain areas, preventing drought from spreading across all continents simultaneously between the different nodes.

It matters more that it doesn’t rain. Another of the findings that may be surprising derives from a common myth about extreme droughts. In this case we usually automatically associate the worst droughts with the suffocating heat wavesbut, nevertheless, the data from the last 120 years are clear in pointing out that the lack of precipitation dominates over high temperatures when determining the severity of a drought. That is to say, it is important that it does not rain or that it is extremely hot.

Specifically, the lack of rain is responsible for two-thirds of the impact of the severity of these events, relegating temperature to a secondary role, although not negligible in a world that is moving towards warming of up to three degrees Celsius.

It’s good news. That the planet has mechanisms to avoid a total global drought is excellent news for global food security and international markets, by ensuring supply for supermarkets. But scientists point out that we should not let our guard down.

It must be kept in mind that, although 6.5% of land affected simultaneously, the maximum possibility that we have mentioned before, seems small on a planetary scale, if that percentage coincides exactly with the great “breadbaskets of the world”, the economic and humanitarian disaster can be equally devastating. In this way, the regions identified as “hubs” host a large part of global agricultural production, and the study warns of a growing systemic vulnerability in these areas.

Images | edcharlie

In Xataka | The drought is turning water into a very scarce and valuable commodity in Spain. And there are already organized groups of thieves