Climate change is one of the biggest challenges facing humanity in the 21st century. It affects not only the environment but also the economy, society, and human health.
One of the most vulnerable sectors to climate change is food production, which is both a key source of greenhouse gas emissions and highly exposed to the effects of extreme weather events.
However, a new study published in Nature Communications suggested that we may be underestimating the risks of harvest failures in multiple global breadbaskets, which could have serious consequences for food security, prices, and social stability.
The researchers warn that we need to be prepared for these types of complex climate risks in the future and that the current models may not capture them adequately.
The impact of the jet stream on crop yields
ANATOLII STEPANOV/AFP via Getty Images
The study, led by researchers from Columbia University and the German Council on Foreign Relations, focused on the impact of the jet stream on crop yields in several major food-producing regions, as per Phys.org.
The jet stream is a band of fast-moving air currents that circulate around the globe at high altitudes and influences weather patterns in many parts of the world.
The researchers found that when the jet stream becomes more wavy and meandering, it can create extreme weather conditions such as heatwaves, droughts, floods, and storms in different regions at the same time.
These events can reduce crop yields by up to seven percent in key agricultural areas such as North America, Eastern Europe, and East Asia.
The researchers also found that these simultaneous crop failures have occurred in the past and are linked to fluctuations in the jet stream.
For example, in 2010, a strong meandering of the jet stream caused both extreme heats in parts of Russia and devastating floods in Pakistan, which both hurt crops and led to a spike in global food prices and social unrest.
The study also looked at how well current climate and crop models assess these risks and found that they may be underestimating them, as per Straits Times.
While the models are good at showing the atmospheric movement of the jet stream, they do not capture the magnitude of the extremes that it can produce on the ground.
The researchers argue that this is because the models do not account for the interactions between different factors that affect crop yields, such as soil moisture, irrigation, pests, and diseases.
They also do not consider the feedback between climate change and land use change, such as deforestation and urbanization, which can alter local weather patterns and affect crop growth.
The researchers suggested that we need to improve our understanding and modeling of these complex climate risks and their impacts on food systems.
More adaptation and mitigation measures to reduce greenhouse gas emissions, enhance crop resilience, and diversify food sources are also some answers they suggested.
The study by Kornhuber et al. (2023) is a wake-up call about the threat that climate change poses to our food systems.
It shows that we may be underestimating the risks of harvest failures in multiple global breadbaskets due to extreme weather events driven by fluctuations in the jet stream.
It also shows that current models may not capture these risks adequately and that we need to improve our knowledge and preparedness for these types of complex climate risks in the future.
