Simultaneous extreme weather events in two major grain-producing regions could threaten food security in many countries. Scientists have now examined the crop losses associated with such events in the past – and ventured into the future as well; that can get expensive.
In the period from 1960 to 2014, adverse general weather conditions in East Asia caused up to seven percent less wheat and maize in the region. The research group led by Kai Kornhuber of Columbia University in New York City has published its results in the journal “Nature Communications”.
“Concurrent crop failures in key growing regions pose a systemic risk, as the associated rising food prices can lead to conflict and malnutrition in import-dependent countries,” the study authors write. They point out that this aspect is barely taken into account in current climate models.
Two granaries are currently at war
For their analysis, the scientists focused on the wheat and maize crops. About two-thirds of the world’s production comes from the regions of North America, Western Europe, Eastern Europe, India and East Asia.
The chart below shows the status prior to Vladimir Putin’s invasion of Ukraine:
High and low pressure areas, which sometimes barely move for weeks and therefore cause drought or extreme precipitation, are usually caused in the northern hemisphere by certain constellations in the jet stream. The polar jet stream is a band of strong winds that winds around the earth at an altitude of nine to twelve kilometers on the border between subtropical warm air and polar cold air.
The jet stream can form large waves, the so-called Rossby waves. If these do not move but remain stationary, high and low pressure areas can remain above an area for a long time. Rossby waves with five and seven crests are known for summers in the northern hemisphere.
North America and East Asia crucial
Kornhuber and colleagues searched historical data (1960 to 2014) for events where more than one granary had low yields associated with Rossby waves. Using multiple models, they determined that in previous seven-peaked Rossby waves, wheat and maize yields were up to seven percent lower in East Asia, six percent lower in North America, and three percent lower in Eastern Europe. For Rossby waves with five peaks, it was 3.7 percent less in Eastern Europe and two percent less in North America.
Researchers examined the likelihood of simultaneous crop losses in two of the granaries in the past. The odds were especially higher when North America was one of the affected regions.
The risk will increase significantly in the future
In the model simulations of the future development (2045 to 2099, with a very strong increase in carbon dioxide emissions), the risk of high crop losses increases, especially when North America and East Asia are affected by the Seven Mountains Rossby waves . With Rossby waves of five mountains, the probability of high crop losses increases when North America and Eastern Europe are affected on the one hand, and India and Western Europe on the other.
Russia’s war against Ukraine last year showed how difficult the world market situation becomes when two of the largest grain suppliers stop exporting grain because of the war. In the course of climate change, weather-related crop failures can lead to even more serious situations. The authors of the study therefore call for more research in this area.
Source: Krone
I am an experienced and passionate journalist with a strong track record in news website reporting. I specialize in technology coverage, breaking stories on the latest developments and trends from around the world. Working for Today Times Live has given me the opportunity to write thought-provoking pieces that have caught the attention of many readers.
