Climate change will have sweeping impacts on agriculture, some of which we’re seeing in real-time with unpredictable precipitation patterns and increases in the severity of extreme weather events. But how do pesticides specifically intersect with climate change? A new report by PAN Organizing Co-Director Asha Sharma, Senior Scientist Margaret Reeves, and Policy Fellow Calista Washburn explores this question, and we’re excited to give you a preview of the analysis.
The bottom line? Pesticides contribute significantly to greenhouse gas (GHG) emissions while, at the same time, climate change is expected to increase pesticide applications. It’s a vicious cycle.
Pesticides drive climate change
Very few studies calculate the GHG emissions of pesticide use over the full life-cycle (production, storage, shipment, application, breakdown) of the chemicals, which likely causes underestimates of true impact. In terms of production, 99% of all synthetic chemicals – including pesticides – are derived from fossil fuels. But they receive much less attention than nitrogen fertilizer, another key agricultural chemical input that creates dangerous levels of GHG emissions. Research has shown that the manufacture of one kilogram of pesticide requires, on average, about 10 times more energy than one kilogram of nitrogen fertilizer!
Pesticides can also release GHG emissions after their application, with fumigant pesticides shown to significantly increase nitrous oxide production in soils. Many pesticides lead to the production of ground-level ozone, a greenhouse gas harmful to both humans and plants.
Climate change & pesticide use
At the same time pesticide use is driving climate change, research shows the effects of our changing climate will likely lead to increased use of synthetic pesticides. Here’s why:
- Rising temperatures, heat stress and altered rain patterns are leading to decreased crop resilience. For example, drought conditions weaken plants’ natural defenses and change their biology, leaving them more vulnerable to pests.
- Rising temperatures will likely stimulate insect population growth in certain regions. Scientists also expect to see continued shifts in insects’ geographic regions and potential to survive winter.
- Because they have more diversity in their gene pool and a greater ability to acclimate, weeds are more resilient to climate change than cultivated crops. Research suggests weeds will have an increased ability to outcompete agricultural crops in many regions, leading to declining yields.
- Climate change speeds up pesticide degradation, meaning pesticides will be effective for less time, leading farmers to increase their pesticide application rates.
An environmental justice issue
Scientists caution that climate change will increase the movement of pesticides away from their intended targets, further polluting our environment and endangering public health. Increased temperatures are expected to result in more pesticide volatilization – when pesticides transform into a gas – meaning more pesticides in our air. Severe rain events are also expected to increase pesticide loss to our waterways.
In the U.S., people living in communities most exposed to pesticides – agricultural workers, rural communities, and residents living where pesticides are produced and wastes are dumped – are disproportionately low-income and people of color. The predicted increase in pesticide use will also compound other climate change effects that impact these communities, such as extreme heat and wildfire smoke.
This is both a climate crisis and a racial injustice.
Despite these findings, the reduction of synthetic pesticide use has been omitted from climate change solutions. Instead, synthetic pesticide use has been presented as a climate change mitigation strategy by industrial agriculture interests.
The real solution addresses all sides of this vicious cycle: agroecology! The adoption of alternative agricultural systems minimizes or eliminates synthetic fertilizer and pesticide use while increasing the resilience of our farming systems to better withstand climate change impacts.
Governments can start by adopting measurable goals to reduce synthetic pesticide use in climate policies. Laws and regulations should be written to uphold and promote the rights of groups most impacted by synthetic pesticide use. And finally, policies should be developed that provide improved technical assistance and incentives for farmers to adopt farming practices that protect community and ecosystem health.
And, while we work toward future policy and practice change, we can collectively support the advocacy work of organizations and impacted communities fighting for climate justice now.