Written in collaboration with Christelle Castet, Head of Science and Ana Pachon, Communications Manager at AXA Climate.
Extreme weather such as drought and heatwaves have a significant impact on crop yields globally, and the recent extraordinary winter drought in France (32 days with no rainfall between January and February 2023) is a clear example (1,2). Rainfall and soil moisture deficits are affecting many regions across Europe, including Ireland, France, England, Northern Italy, Portugal, and the Mediterranean Basin, which could lead to higher competition for water resources during the summer (Figure 1). Winter rainfall is crucial for recharging underground water tables, which is essential to ensure water availability in spring and summer. Without sufficient recharge, irrigation may be restricted during the warm season, potentially leading to lower yields, increased prices, and economic instability.
Beyond the Headlines: The Lasting Impacts of Recent Climate on Agriculture
Globally, extreme climate conditions can lead to a remarkable gap between global supply and demand, putting food security at high risk. According to the World Bank database, the number of people suffering acute food insecurity increased from 135 million in 2019 to 345 million in 82 countries by June 2022 (3), a large part of which is attributed to climate change and extreme weather conditions. For instance, in Sub-Saharan Africa, South Asia, and Southeast Asia, around 80% of the global population is significantly impacted due to an important yield loss, caused by climate change (1).
Figure 1: Current drought situation in Europe (European Drought Observatory, 2023).
2022 was a year that broke many records in terms of extreme heat and drought conditions around the world, putting the food sector at stake.
A recent report (5) states that the current winter drought in Europe comes after an unusual hot and dry summer, when crop yields dropped by a lot (4). Waterways often used for irrigation, like the Loire in France, the Po River in Italy (Figure 2), and the Rhine in Germany, dried up, impacting agriculture, trade, and hydropower supplies. This led to a marked decrease in the harvest of several key crops such as grain maize (-8.6% at EU level), sunflowers (-5.5%), and soybeans (-9.6%) (6). Indeed, as drought occurs, the rate of photosynthesis decreases rapidly. This shortens the growing period, which in return lowers the crop yield (7). In other parts of the world, China’s Yangtze River and the Horn of Africa suffered 3 years of consecutive droughts, leading to a 70% decrease in harvest.
In 2022, a large swathe of the world also experienced record-breaking heat waves that touched hundreds of millions of people over China, Europe, large parts of South America, and several southwest and central US states (8). (9). What was particularly worrying was that these increases in temperatures occurred unusually early in the season. For example, France experienced its warmest May since records began in 1900. What was even more surprising was that it wasn’t just during the summer months that unprecedented heatwaves were observed. The autumn months were also plagued by warmer-than-usual temperatures. Europe recorded its third warmest autumn on record, with temperatures on the continent recorded as 2 °C above average in October (10).
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Figure 2: Copernicus Sentinel-2 animation shows a part of the Po Valley, near Piacenza (June 2020- June 2022)
What Do We Know About Climate Change…
Droughts are the first cause of famines, and future climate projections show an increase in the frequency and intensity of droughts in several regions around the world. Scientists in the latest IPCC report (11) state with medium confidence that agricultural and ecological droughts have increased over Western North America (WNA) and the Mediterranean (MED) since the 1950s as a result of climate change (Figure 3). And for every 0.5°C of global warming, there will be a clear increase in the intensity and frequency of these droughts, in addition to the occurrence of events that will be unprecedented in recent history over many regions worldwide (IPCC, 2021).
Learn more about droughts
Extreme heatwaves are also expected to happen more often. if greenhouse gas emissions do not decrease. These extreme temperatures can have various negative impacts, for instance on health and well-being; an increase in energy demand as people try to keep cool; transportation; natural ecosystems; and, of course, agriculture, food security, and farming revenue by affecting growing seasons.
Figure 3: Agricultural and ecological droughts (yellow colour) attributed to climate change (dots). Each hexagon corresponds to one of the IPCC AR6 WGI reference regions. IPCC
Unfortunately, the likelihood of having more simultaneously dry and hot years (compound extreme events) has been growing in different regions of the world (12), and this pattern is projected to continue in the decades ahead under various greenhouse gas emissions scenarios. This increasing probability will thus heighten the threat to the food supply chain.
… And other Planetary Boundaries.
In addition to climate change, scientists from the Stockholm Resilience Centre have identified 8 other limits beyond which the planet’s systems could not be pushed any further without significantly increasing risk on our existence. These limits are called ‘The Planetary Boundaries’.
The planetary boundaries are interlinked, so crossing one could have an impact on the risk of crossing another, which could further exacerbate the problem (14). Scientists announced in 2022 that we had crossed the freshwater planetary boundary, making it the sixth boundary that we had crossed (15). Other boundaries already crossed are climate change, biosphere integrity, biogeochemical cycles, land-system change, and novel entities that represent pollution by synthetic substances.
All of these boundaries are impacted by farming practices, and the agricultural sector is also impacted by the transgression of these boundaries and must therefore adapt. This concept is called double materiality.
Learn more about planetary boundaries
Better Late Than Never: The Importance of Adapting Our Food Systems to Climate Change and Embracing Solutions Already Available
As it becomes clearer that reversing all aspects of climate change will be difficult, attention needs to turn to how we manage to adapt to the changes that can’t be avoided. For this reason, many farming approaches have been proposed, discussed, and evaluated, for the sake of both achieving global food security, and reducing environmental damages (e.g., reduction of synthetic inputs). Some of these farming approaches have been well defined in the scientific literature (e.g., organic agriculture (17), integrated farming (18), and sustainable agriculture (19)). However, a ‘novel’ approach has been receiving particular attention in the literature, which is the ‘Regenerative Agriculture’ (RA) (20). Even though many definitions could be found in the literature due to the concept’s originality, some definitions describe extensively the purpose of adopting such a system. For instance, Elevitch et al. (21) describe RA as a farming approach that can achieve self-renewal and resiliency, improve soil health and quality, increase water percolation and retention, conserve biodiversity, and sequester carbon.
Hence, taking this into account, RA could help prevent the crossing of several planetary boundaries by mitigating climate change, decreasing freshwater and land use, reducing nitrogen and other macronutrients leaching to ground water, and decreasing aerosols emissions. In addition, when adopting a highly diversified crop rotation, RA would reduce the pressure on soil microbial community, increase the micro-organisms richness and diversity, and improve soil physical and chemical properties, which would lead to increasing soil water holding capacity and therefore reducing erosion risk and limiting drought consequences (22).
To wind up, it is very essential that we change our view and perspective on the whole food chain. The agricultural system could be seen as a part of the natural sequence that alters the environment and is influenced by the changes affecting our planet. Production must be done responsibly in order to sustain the well-being of societies on Earth.
