Introduction
Climate change is a global phenomenon that impacts all aspects of the environment, including agriculture. The most immediate effects of climate change, such as increased temperatures and extreme weather occurrences, have put increased pressure on food security and have caused considerable drops in agricultural yields. In fact, the Intergovernmental Panel on Climate Change estimates that the impact of climate change will be felt as early as 2020 and will have a “severe, pervasive and irreversible” effect on global food production by 2050.
Agriculture is a vitally important industry and is responsible for human sustenance and economic livelihoods. Climate change creates an array of challenges to the production of food, threatening the availability and security of food sources for all nations. So, how exactly does climate change threaten current and future food production? In this article, we will explore the various negative impacts of climate change on agriculture, focusing on the most pertinent and imminent threats.
Changes in Global Average Temperatures
Climate change has resulted in a marked shift in global average temperatures. Since 1880, average global temperatures have increased by 1.4 degrees Fahrenheit (0.8 of a degree Celsius). Regional temperature increases have been greater, with some regions experiencing greater than 5 degrees Fahrenheit of warming in the same period.
This increase in global temperatures has wide-reaching consequences for agriculture. Compared to the pre-industrial era, when most of the world was within an ideal temperature range for agricultural production, temperature increases have moved many regions outside of the optimal range. The increased temperatures lead to droughts, extreme weather events, and altered seasons all of which create difficulties and new challenges for farmers.
Heat Stress
As temperatures rise, the periods of extreme heat will become increasingly more common, triggering heat stress on all types of crops. Heat stress is a serious problem for all agricultural products, especially for those grown in warmer climates as it can cause crops to die or produce lower yields. Heat also increases the stress of pests on crops, resulting in even lower yields and extreme cases of complete crop destruction.
To manage the effects of heat stress, farmers have to increase the use of irrigation and other water management techniques, resulting in higher costs and greater water usage, which can lead to water scarcity. This can create conflict between farmers and local authorities, who are trying to reduce water use and manage competing needs.
Changes in Rainfall Patterns
Climate change can result in changes in the regional pattern of rainfall. The distribution and timing of rain can alter substantially and can lead to greater rates of erosion and flooding, both of which can be devastating to crops.
Flooding can damage crops by burying them beneath sediment or causing them to wither and die due to excess moisture. The destruction of farm infrastructure caused by flooding can also result in the loss of crops and substantial losses in production.
Droughts can also have a huge impact on crops, leading to withering and death, and resulting in decreased yields. In areas of Africa and Asia, where drought-prone areas are expanding, prolonged periods of drought can create huge losses of income for farmers and put increased pressure on food security in those regions.
Rising Carbon Dioxide Levels
Carbon dioxide (CO2) levels in the atmosphere have risen exponentially since the industrial revolution and is now at levels higher than at any point in the past 800,000 years.
Carbon dioxide’s main effect on agriculture is a process called ‘CO2 fertilization’. This occurs when plants are exposed to higher levels of CO2, resulting in the plant being able to absorb more water, nutrients and energy from the soil. This makes the plant more resilient to heat and water stress, increasing its growth and yields.
However, CO2 also has a downside, as it also increases the amount of water that the plant requires, while at the same time reducing the amount of water available to the plant due to increased rates of evaporation. As temperatures get hotter, crop production could actually suffer due to this.
Weed and Pest Intensification
The increased temperatures and increased CO2 levels associated with climate change have resulted in an increase in the intensity of pests and weeds. This can lead to a decrease in crop yields and quality, as the weeds outcompete the crops for resources such as sunlight, water, and nutrients.
It also presents a greater challenge for farmers to control weeds, as some weeds are becoming more resistant to the traditional modes of control such as herbicides and mechanical removal. This increases the cost of production and can lead to increased losses for the farmers.
Soil Erosion
Soil erosion is the degradation and destruction of the soil, resulting in a decrease in soil fertility and therefore, a decrease in agricultural production. Climate change increases the risk of serious erosion in two ways.
First, climate change creates extreme weather conditions, such as more intense and frequent storms, which can cause increased levels of soil erosion. Second, the increased temperatures dry out the soil, making it harder for plants to access the water they need and also making it more susceptible to soil erosion.
Erosion also affects soil composition and can lead to soil contamination and a loss of soil structure, making it much harder for farmers to produce food in an efficient and sustainable way.
Conclusion
The evidence is clear: climate change is having a severe and pervasive effect on agricultural production. The gradual transition in temperatures, changes in the pattern of rainfall, increased carbon dioxide levels, heightened intensity of weeds and pests, and soil erosion all contribute to a decrease in crop yields and an increase in the cost of production.
Governments, businesses, and individuals must take urgent action to reduce the impact of climate change and ensure food security for generations to come. If these changes are not addressed, the consequences for food production and security in the future could be drastic.