9. Agriculture and Food
Rising temperatures, extreme heat, drought, wildfire on rangelands, and heavy downpours are expected to increasingly disrupt agricultural productivity in the United States. Expected increases in challenges to crop health, declines in crop yields and quality, and changes in extreme events in the United States and abroad, threaten rural livelihoods, sustainable food security and price stability.
Climate change presents numerous challenges to sustaining and enhancing crop productivity, livestock health and the economic vitality of rural communities. While some regions such as the northern great plains may see conditions conducive to expanded or alternative crop productivity over the next few decades, overall yields from major U.S. crops are expected to decline as a consequence of increases in temperatures, possibly changes in water availability, soil erosion and disease and pest outbreaks. Increases in growing temperatures during the growing season in the Midwest are projected to be the largest contributing factor to declines in the productivity of U.S. agriculture. Projected increases in extreme heat conditions are expected to lead to further heat stress for livestock which can lead to large economic losses for producers. Climate change is also expected to lead to large scale shifts in the availability and prices of many agricultural products around the world with corresponding impacts on U.S. agricultural producers, and the U.S. economy. These changes threaten future gains in commodity crop production and poor rural life hoods at risk.
2015, USDA, Climate Change, Global Food Security, and the U.S. Food System
The assessment finds that climate change is likely to diminish continued progress on global food security through production disruptions leading to local availability limitations and price increases, interrupted transport conduits, and diminished food safety, among other causes. ...damaging outcomes become increasingly likely in all cases from 2050–2100 under higher emissions scenarios.
As climate change continues and temperature increases of 1–3 °C are coupled with
changes in precipitation timing and intensity, yields and farm returns are projected to decline. The
continued changes expected between 2050 and 2100 under high-emissions scenarios are expected to have overall detrimental effects on most crops and livestock. Finally, it should be recognized that there is a significant chance that current projections underestimate potential declines, because most analyses exclude production constraints arising from increased pest pressures, extreme events, and decreased ecosystems services