Middle East: No good climate prospects

Long-term climate cycles indicate that the climate is still dry

For the Near and Middle East, there could be little prospect of a more favorable climate. © NASA
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No hope for improvement: the Middle East must continue to expect continued periods of drought in the future. After all, even natural climatic fluctuations are unlikely to lead to any increase in precipitation in the near future, as researchers have determined. Rather the opposite: Long-term climate trends could increase the increased drought and heat caused by climate change.

The Middle East is not only politically a powder keg - also in terms of climate, this region has not pulled the big deal. In the once fertile crescent, the worst period of drought has been raging for over 900 years. The drought is considered as a co-trigger of the civil war in Syria. In addition, climatologists predict that the summers could become life-threatening in parts of the Middle East - even with modest climate change.

Further evidence of unfavorable prospects is now provided by a study by researchers led by Sevag Mehterian of the University of Miami. They have reconstructed the climate variability of the region over the last 120, 000 years and have proven certain laws. They managed to do this using stalagmites from a cave in northwestern Iran. The oxygen isotopes conserved therein provide information about the climate of the past.

Long-term trend towards more dryness

The result: The climate reconstruction confirms that the climate of the Middle East is closely linked to long-term variations in the climate over the Atlantic Ocean and even longer-term changes in solar radiation. However, both factors are currently unfavorable for the Middle East - and will not change as soon as the researchers report.

What stalagmites from an Iranian cave reveal about the climate of the past and the future © University of Miami

"Local governments like to explain that the region is experiencing only a temporary dry spell and that there will be more water soon, " says Mehterian. "But our study has found evidence to the contrary. It speaks in favor of a long-term trend towards less rainfall. "Specifically, there is little prospect in the future that the Mediterranean storms - the region's main rainblower - will re-emerge in the near future. display

Unfavorable Earth orbit parameters

One of the reasons for this is, so to speak, cosmic nature: The solar radiation to the northern hemisphere of the earth fluctuates among other things over the course of more than 20, 000 years, because the axis of the earth changes its inclination. This precession changes the angle of the incident radiation and thus the amount of radiation and heat energy that hit the earth's surface.

Past fluctuations in precipitation as a function of solar radiation University of Miami

A look into the climate history showed that it always became drier in the Near and Middle East when the sun's radiation decreased due to these orbital factors. And even now, the conditions for this region are rather unfavorable: "Precipitation only increases again with higher radiation incidence and increased seasonality of an orbital configuration, that will not happen until about 10, 000 years from now, "say Mehterian and his colleagues.

No compensation for climate change in sight

In concrete terms, even if the impact of such long-term cycles is rather small, they contribute to the short-term dry seasons by the long-term effect of the North Atlantic Oscillation (NAO) and the already noticeable consequences of climate change. The Middle East can not hope that natural factors will offset or mitigate the effects of manmade climate warming in the near future. (Journal of Quaternary Science, 2017; doi: 10.1016 / j.quascirev.2017.03.028)

(University of Miami Rosenstiel School of Marine & Atmospheric Science, 11.07.2017 - NPO)