climate crisis – Extreme heat and storms are already damaging major crops and food supplies worldwide, raising pressure on prices and worker safety.
A warming world is quietly but decisively rewriting what ends up on supermarket shelves, and the bill may show up first in your groceries.
Two years ago. a severe heat wave struck large parts of Brazil for days at a time. with temperatures in the central and southern regions soaring during a five-day stretch at the end of April 2024.. Many communities were still recovering from another earlier bout of extreme heat that had already battered southern Brazil.. Even within that longer stretch of abnormal weather. the risk has been stark: in Rio de Janeiro. the heat index reached 144.1 degrees Fahrenheit in the month before that five-day episode. the highest reading in a decade.
Those events are part of a broader pattern of prolonged. intense heat that has repeatedly hit one of the world’s most important agricultural exporters.. Over several years. yields of soy and corn declined in southeastern areas including São Paulo. while other staples and high-value crops—including peanuts. potatoes. sugarcane. and arabica coffee—also suffered widespread losses.. Livestock were not spared; pigs in Brazil’s central-west were reported to have endured severe heat stress for much of a year.
The disruptions did not stay neatly within the category of “heat.” When an atmospheric cold front was blocked by a prevailing heat dome. it contributed to devastating rainfall and flooding across Rio Grande do Sul. the southernmost state.. That sequence of extremes disrupted supply chains and markets for pink shrimp throughout Brazil. illustrating how different kinds of weather hazards can compound each other rather than acting alone.
A new joint report released last month by the World Meteorological Organization and the Food and Agriculture Organization of the United Nations ties these events to a larger global agricultural challenge: extreme heat is increasingly shaping how food can be produced. and the report argues that the compounding effects are now visible in real market and production outcomes.. By combining weather datasets with agricultural records. the authors trace how prolonged heat and shifting weather extremes can ripple through farming systems and trading networks.
Brazil is the report’s only country-level case study examined in detail. and the focus is on how warming temperatures and the oscillating swings of El Niño and La Niña are applying outsize pressure to exports.. The report also points to other countries. widening the lens beyond one national story while preserving the same underlying message: extreme weather is increasingly a structural risk for agriculture.
In Chile. the report describes how warming ocean conditions in 2016 contributed to major algae blooms that killed an estimated 100. 000 metric tons of farmed salmon and trout. an event characterized as the largest aquaculture mortality case in history.. In the United States. the report points to the Pacific Northwest’s 2021 heat wave. describing losses that ranged from entire raspberry and blackberry harvest failures to large declines on Christmas tree farms.. It also links the combination of extreme heat. vegetation drying. and wildfires to an increase in forest area burned across North America that year.
The document also recounts the cascading impacts elsewhere: after a record heat wave hit India in 2022. wheat was reported to fall in more than a third of Indian states. with declines ranging across a broad span.. The report says dairy animals experienced heat stress that reduced milk production. and it notes that some cabbage and cauliflower yields were cut roughly in half.. In Kyrgyzstan’s Fergana mountain range—an area known for year-round snow—the report describes spring temperatures rising about 50 degrees Fahrenheit above the seasonal average. with that unusual shift tied to a locust outbreak and dramatic declines in cereal harvests.
Underlying these country stories is a broader acceleration in human-caused warming. which the report characterizes as increasing at an unprecedented pace.. The past 11 years are described as the 11 warmest years on record. and the report’s authors argue that efforts are not moving fast enough to prevent the residual risks from continuing to grow.. As Martial Bernoux of the FAO’s office for climate change. biodiversity. and the environment put it. the speed of response is not adequate and the dangers do not simply disappear after extreme events.
On a higher-emissions path. the report warns that by the end of the century. large regions could face as many as 250 days per year that are simply too hot for outdoor work in parts of South Asia. tropical sub-Saharan Africa. and sections of Central and South America.. The implication for food systems goes beyond crop yields: heat affects who can work. how long. and what tasks remain possible during critical agricultural seasons.
The health and labor dimension is already considered urgent.. A 2024 report cited in the broader coverage from the International Labour Organization found that extreme temperatures placed more than 70% of the global workforce—about 2.4 billion people—at high risk.. That finding helped drive a call to action on extreme heat in summer 2024 by UN Secretary-General António Guterres. who urged governments and international partners to prioritize support for the most vulnerable. strengthen protections for workers exposed to excessive heat. improve resilience with data and science. and phase out fossil fuels in a quick and equitable way.
Guterres also framed heat as a lethal threat on a massive scale. saying it is estimated to kill nearly half a million people each year. describing that as far higher than tropical cyclones.. He pointed to fossil fuel-driven, human-induced climate change as the driver, and warned that the risk is expected to worsen.
The FAO and WMO joint analysis was described as a direct response to that call to action.. Bernoux said the UN message was essentially that a problem exists. and that the agencies decided to work together to provide a reply.. The report’s structure aims to connect weather extremes with agricultural outcomes. but it also sets the stage for decisions about how the global system adapts as extreme heat becomes more routine.
Still, not all experts are satisfied with how fully the report reflects the people doing the work.. Naia Ormaza Zulueta. a postdoctoral researcher at the University of British Columbia who studies extreme heat and the agricultural workforce. questioned whether the report gives enough attention to those who grow. harvest. and raise food.. While she said the diagnostic parts are sharper than anything previously available and represent a meaningful breakthrough in how climate change and food systems are treated as interconnected. she argued the prescription has not caught up.
Zulueta raised a specific concern about how dangerous exposure is calculated.. She said the worker exposure assessment omits both hourly and nighttime wet-bulb conditions—measures that can better capture how severe heat stress is for outdoor laborers compared with daily averages.. In her view, that could mean the report likely undercounts the number of days when heat becomes dangerous.
She also said the adaptation recommendations tilt heavily toward crops. livestock. and ecosystems. emphasizing steps such as adjusting planting timing. developing heat-tolerant breeds. and investing in large-scale irrigation systems.. In contrast. she said direct recommendations for agricultural laborers appear only in passing references to existing international agreements on worker safety and health adopted more than a decade ago.
Even within the report’s focus on finance and early warning, she said the roadmap remains incomplete.. The report calls for dramatically increasing climate-related development finance for food systems and expanding early-warning systems to reduce compounding risks from extreme heat. but Zulueta argued that it does not provide a clear. concrete approach for adapting food production in ways that protect the billions of outdoor workers exposed as temperatures intensify.
A further complication. she suggested. is the process behind the report itself: she questioned whether the UN agencies responsible for worker rights were involved.. If that institutional separation persists. Zulueta said. it helps explain why the workforce is more visible in the “diagnosis” than in the “prescription”—a gap she described as leaving the human dimension. and the practical realities that come with it. largely missing.
The broader warning from the report is that extreme heat is no longer a distant forecast; it is already shaping yields. livestock health. and supply chains. as seen in Brazil’s crop losses and shrimp disruptions.. With climate risks increasingly intertwined—heat. blocked fronts. flooding. and shifting ocean conditions—the food system faces a challenge that spans both production and the people who labor outdoors.. For consumers. that means the grocery aisle may increasingly reflect the cost of weather extremes long before the full political and economic response is felt.
climate crisis extreme heat food prices agriculture Brazil heat wave worker safety