Study: Effect of extreme heat on crops is underestimated – 7/4/2023 – Market

The risk of climate change affecting wheat harvests in the world’s main granaries is greatly underestimated, points out a study published this Tuesday (4), which warns of the possibility of destabilizing the world food system.

The probability of bad harvests or lower simultaneous yields in the main producing regions is increasing, points out the report, prepared by researchers based in the United States and Germany and published in the journal Nature.

Falling harvests in several regions could lead to soaring prices, food insecurity and even civil unrest, lead author Kai Kornhuber of Columbia University told AFP.

The scholar recalled what happened in 2010, when crops were affected by extreme heat in Russia and floods in Pakistan, with major global repercussions.

Food production is one of the main causes of greenhouse gas emissions and therefore of global warming, while at the same time being highly exposed to its consequences.

The study focused on meteorological data and climate models from 1960 to 2014, and made simulations for the period 2045-2099.

First, the impact of the “jet-stream” —air currents at height that determine meteorological conditions— was examined in the main cereal producing regions of the world. It was found that a jet-stream with strong oscillations has important repercussions in North America and in Eastern Europe and Asia, with a reduction in crops of up to 7%, a phenomenon that played an important role in the 2010 crisis.

The study also demonstrated that the current computer models correctly predict the atmospheric movement of the jet-stream, but underestimate the dimension of the extreme phenomena resulting from it.

The study “alerts to our uncertainties” related to the impact of climate change on the food sector, noted Kai Kornhuber. “We have to prepare for this kind of complex climate risk and current models don’t seem to take it into account.”