There are numerous effects of climate change on agriculture, many of which are making it harder for agricultural activities to provide global food security. Recent research has found that climate change is likely to exacerbate the existing environmental impacts of agriculture by lowering crop productivity, reducing the effectiveness of agrochemicals, increasing soil erosion and pest pressures, and thereby driving greater use of land, water and inputs. Rising temperatures and changing weather patterns often result in lower crop yields due to water scarcity caused by drought, heat waves and flooding. These effects of climate change can also increase the risk of several regions suffering simultaneous crop failures. Currently this risk is rare but if these simultaneous crop failures occur, they could have significant consequences for the global food supply. With a growing population and rapid urbanization, it is suggested that food production may increase by nearly 60% in the upcoming years. Many pests and plant diseases are expected to become more prevalent or to spread to new regions. The world's livestock are expected to be affected by many of the same issues. These issues range from greater heat stress to animal feed shortfalls and the spread of parasites and vector-borne diseases.
The increased atmospheric level from human activities (mainly burning of fossil fuels) causes a fertilization effect. This effect offsets a small portion of the detrimental effects of climate change on agriculture. However, it comes at the expense of lower levels of essential micronutrients in the crops. Furthermore, CO2 fertilization has little effect on C4 crops like maize. On the coasts, some agricultural land is expected to be lost to sea level rise, while melting glaciers could result in less irrigation water being available. On the other hand, more arable land may become available as frozen land thaws. Other effects include erosion and changes in soil fertility and the length of growing seasons. Bacteria like Salmonella and fungi that produce mycotoxins grow faster as the climate warms. Their growth has negative effects on food safety, food loss and prices.
Extensive research exists on the effects of climate change on individual crops, particularly on the four staple crops: corn (maize), rice, wheat and soybeans. These crops are responsible for around two-thirds of all calories consumed by humans (both directly and indirectly as animal feed). The research investigates important uncertainties, for example future population growth, which will increase global food demand for the foreseeable future. The future degree of soil erosion and groundwater depletion are further uncertainties. On the other hand, a range of improvements to agricultural yields, collectively known as the Green Revolution, has increased yields per unit of land area by between 250% and 300% since 1960. Some of that progress will likely continue.
Global food security will change relatively little in the near-term. 720 million to 811 million people were undernourished in 2021, with around 200,000 people being at a catastrophic level of food insecurity. Climate change is expected to add an additional 8 to 80 million people who are at risk of hunger by 2050. The estimated range depends on the intensity of future warming and the effectiveness of adaptation measures. Agricultural productivity growth will likely have improved food security for hundreds of millions of people by then. Predictions that reach further into the future (to 2100 and beyond) are rare. There is some concern about the effects on food security from more extreme weather events in future. Nevertheless, at this stage there is no expectation of a widespread global famine due to climate change within the 21st century.
Direct effects from changing weather patterns Observed changes in adverse weather conditions
Agriculture is sensitive to weather, and major events like heatwaves or droughts or heavy rains (also known as low and high precipitation extremes) can cause substantial losses. For example, Australia's farmers are very likely to suffer losses during the El Nino weather conditions, while 2003 European heat wave led to 13 billion euros in uninsured agriculture losses. Climate change is known to increase the frequency and severity of heatwaves, and to make precipitation less predictable and more prone to extremes, but since climate change attribution is still a relatively new field, connecting specific weather events and the shortfalls they cause to climate change over natural variability is often difficult. Exceptions include West Africa, where the climate-induced intensification of extreme weather was found to have already decreased millet yields by 10–20%, and sorghum yields 5–15%. Similarly, it was found that climate change had intensified drought conditions in Southern Africa in 2007, which elevated food prices and caused "acute food insecurity" in the country of Lesotho. Agriculture in Southern Africa was also adversely affected by drought after climate change intensified the effects of 2014–2016 El Niño event.
In Europe, between 1950 and 2019, heat extremes became more frequent and more likely to occur consecutively, while cold extremes have declined. At the same time, Northern Europe and much of Eastern Europe was found to experience extreme precipitation more often, while the Mediterranean became more affected by drought. Similarly, the severity of heatwave and drought effects on European crop production was found to have tripled over a 50-year period – from losses of 2.2% during 1964–1990 to losses of 7.3% in 1991–2015. Available under CC BY 4.0. In the summer of 2018, heat waves probably linked to climate change greatly reduced average yield in many parts of the world, especially Europe. During the month of August, more crop failures resulted in a rise in global food prices.
On the other hand, floods, often linked to climate change, have also had notable adverse effects on agriculture in the recent years. In May 2019, floods shortened corn planting season in the Midwestern United States, lowering the projected yield from 15 billion bushels to 14.2. During the 2021 European floods, estimates pointed to severe damage to the agricultural sector of Belgium, one of the countries hardest hit by the floods, including long-term effects like soil erosion. In China, 2023 research found that extreme rainfall had cost the country about 8% of its rice output over the two preceding decades. This was considered comparable to losses caused by extreme heat over this period.
Projected effects from temperature increase
Changes in temperature and weather patterns will alter areas suitable for farming. The current prediction is that temperatures will increase and precipitation will decrease in arid and semi-arid regions (Middle East, Africa, Australia, Southwest United States, and Southern Europe). In addition, crop yields in tropical regions will be negatively affected by the projected moderate increase in temperature (1–2 °C) expected to occur during the first half of the century. During the second half of the century, further warming is projected to decrease crop yields in all regions including Canada and the Northern United States. Many staple crops are extremely sensitive to heat and when temperatures rise over , soybean seedlings are killed and corn pollen loses its vitality. Warmer temperatures also contribute to the spread and growth of pests and diseases. According to some estimates, a 1 °C increase in global temperature could result in a 10–25% decline in crop yields in the future due to pest growth. According to the Intergovernmental Panel on Climate Change (IPCC) 2023 Synthesis Report, global surface temperature has increased by approximately 1.1 °C above the 1850–1900 average.
Higher winter temperatures and more frost-free days in some regions can currently be disruptive, as they can cause phenological mismatch between flowering time of plants and the activity of pollinators, threatening their reproductive success. In the longer term, however, they would result in longer growing seasons. For example, a 2014 study found that maize yields in the Heilongjiang region of China increased by between 7 and 17% per decade as a result of rising temperatures. On the other hand, a year 2017 meta-analysis comparing data from four different methods of estimating effect of warming (two types of climate model, statistical regressions and field experiments where land around certain crops was warmed by a certain amount to compare them with the controls) concluded that on a global scale, warming alone has consistently negative effects on the yields of four most important crops, suggesting that any increases would be down to precipitation changes and the CO2 fertilization effect. A 2025 systematic review found that, without effective adaptation measures, climate change could reduce global agricultural food production by up to 14% by 2050.Farah, A. A.; Mohamed, M. A.; Musse, O. S.; & Nor, B. A. (2025). "The multifaceted impact of climate change on agricultural productivity: A systematic literature review of SCOPUS-indexed studies (2015–2024)." *Discover Sustainability*, 6(1). Springer Nature. doi:[10.1007/s43621-025-01229-2](https://doi.org/10.1007/s43621-025-01229-2).
A 2026 joint report by the Food and Agriculture Organization (FAO) and the World Meteorological Organization (WMO) identified 25°C as a critical temperature threshold beyond which crop yields begin to decline significantly, with effects on harvests and food prices persisting for up to a year.
Heat stress in livestock
Changes in agricultural water availability and reliability
Both droughts and floods contribute to decreases in crop yields. On average, climate change increases the overall amount of water contained in the atmosphere by 7% per every , thus increasing precipitation. However, this increase in precipitation is not distributed evenly in space (atmospheric circulation patterns already cause different areas to receive different amounts of rainfall) or time: heavy rainfall, with the potential to cause floods, becomes more frequent. This means that under the probable mid-range climate change scenario, SSP2-4.5, precipitation events globally will become larger by 11.5%, yet the time between them will increase by an average of 5.1%. Under the highest-emission scenario SSP5-8.5, there will be an 18.5% increase in size of events and 9.6% increase in the duration between them. At the same time, water losses by plants through evapotranspiration will increase almost everywhere due to higher temperatures. While the fertilization effect also reduces such losses by plants, it depends on the area's climate which effect will dominate. As such, the 2020–2023 Horn of Africa drought has been primarily attributed to the great increase in evapotranspiration exacerbating the effect of persistent low rainfall, which would have been more manageable in the cooler preindustrial climate.
In total, this means that droughts have been occurring more frequently on average because of climate change. Africa, southern Europe, the Middle East, most of the Americas, Australia, South and Southeast Asia are the parts of the globe where droughts are expected to become more frequent and intense in spite of the global increase in precipitation. Droughts disturb , and these effects can be aggravated by population growth and urban expansion spurring on increased demand for water. The ultimate outcome is water scarcity, which results in crop failures and the loss of pasture grazing land for livestock, exacerbating pre-existing poverty in developing countries and leading to malnutrition and potentially famine.