Regardless of all other factors, higher global temperatures alone will cause an increase in the price of food in the range of 0.9% to 3.2% per year, a price that will add between 0.3% and 1.2% per annum to inflation, according to a study by Maximilian Kotz from the Potsdam Institute for Climate Impact Research, done in collaboration with the European Central Bank (“Food Is Costing More Due to Climate Change—Prices Will Keep Rising”, New Scientist, March 30, 2024).
This is bad news for consumers. It is also bad news for governments and central banks that want to keep inflation below 2%. If about half the inflationary target is the unstoppable rise in food prices, then those agencies that are trying to regulate the value of currencies will have less latitude to account for the cost of energy, wages, housing, commodities, transportation and all the other costs that they want to control to keep economies functioning and societies contented.
The study by Kotz compared the cost of monthly food in 121 countries between 1996 and 2021, and then correlated these prices to weather conditions such as rain, drought and heat. The rising price of food followed the climate extremes a few months later. In areas north of 40° latitude—New York, Madrid and Beijing—winter food prices actually fell for a short time, but rose again during hot summers. In the rest of the world, and for the rest of the time, prices rose.
Extreme rainfall events that were localized did not affect food prices, but high temperatures did, presumably because they were more widespread.
The Kotz study, in a worst case scenario of greenhouse gas emissions, calculated prices to rise 4% per year by 2060. If all other factors remained the same, food prices would be 2.44 times more expensive. But the study supported a possible 3.2% rise per year up to 2035, which would mean that food prices would be 1.44 times more expensive in 11 years.
The study did not allow for farmers changing their growing techniques, or for new kinds of crops to be developed—genetically altered plants are being designed to be more salt and heat resistant. And the study did not address the problem of soil loss. Neither did it account for the availability of fresh water to farm food crops, an issue that is now becoming a consideration in an age of increasing droughts, depleted aquifers and receding glaciers. It also did not consider the rising demand for food as per-capita consumption increases with affluence, which is occurring in tandem with a larger global population of consumers.
Of course, heat alone is not the sole factor influencing the availability, and thus the price of food. Erratic weather will have the same effect. Unseasonably cold weather brought southward by “polar vortexes” can have devastating effects on traditional food production. An unseasonable cold spell can decimate fruit crops such as grapes, oranges, cherries, peaches and apples.
Generally, biological activity tends to increase with warmer temperatures, which is why the tropics are so lush and active. As this activity moves northward with the global temperature rise, crops will be exposed to threats they have not previously encountered, such as alien forms of fungi, insects and diseases. Tropical pests have been working their way northward, threatening crops that were once removed from their scourge.
Insects remain an unpredictable factor. Their populations are declining dramatically—worldwide estimates are nearly 50% in the last four decades. And about one-third of our food is dependent on insect pollination. But declining insect populations in tandem with declining bird populations that eat the insects that eat our food is another unpredictable that will affect food availability and prices.
Rising temperatures displace crops from the traditional places where they have been grown, thus requiring relocation—if that is even possible. Topography, soil, water and climate have to be compatible with the food that is being grown. Neither forests nor tundra may be suitable for growing grains or corn at the industrial levels that are required to feed more than 8 billion people. Most regions have grown particular crops for centuries because of the compatibility of many factors, but this doesn’t mean that a forced migration of agricultural sites will provide appropriate territory at a more northerly location. As for the latitudes adjacent to the equator, they might become too hot or dry for growing anything—an unmitigated disaster not only for the hundreds of millions of people presently living there, but for the availability and prices of food everywhere.
Our successful food production has been facilitated by the Holocene, the 12,000 years of climate stability that followed the end of the last Ice Age. Our greenhouse gas emissions are now dismantling this stability. As scientists have been telling us for decades, our carbon dioxide emissions are raising global temperatures and initiating a vast experiment with complex consequences that we are barely capable of imagining. Perhaps the Kotz study will start us thinking and moving us toward more serious CO2 reductions.
Ray Grigg for Sierra Quadra
Top image credit: According to the European farming organization Copa & Cogeca, the cereal harvest in Southern Europe was down 60% in 2023 because of the drought and heat wave that year. Photo of wheat stalks by lamoix via Flickr (CC By 2.0)