Agriculture and Climate
Rising average temperatures can extend the growing season in areas with previously cool springs and autumns, but can also be detrimental to crops in areas with already high temperatures. Soil evaporation rates and the chance of severe drought also increase with rising temperatures.
Changes in rainfall affect crop yields by altering soil erosion rates and the amount of moisture in soil. As a result of global warming, precipitation will likely increase most in high latitudes and decrease in subtropical land regions. Rainfall may decrease by up to 20 percent in these areas, causing an increase in other extreme weather events.
The rise of atmospheric carbon dioxide levels may at first seem like a blessing for crops. The gas does have fertilizing properties that can be beneficial for some crops like rice, soybeans and wheat, but the positive effects of carbon dioxide on plants are more than countered by the overall negative effect that the greenhouse gas has on global temperatures.
Pollution has a significant effect on agriculture and climate. Crop growth is limited by high levels of ozone in the lower atmosphere, and climate change increases ozone concentrations. The negative effects of increased ozone also offset any benefits that carbon dioxide may have on crops.
A 2007 European Union study examined the relationship between agriculture and climate and projected the impact of global warming on the region. In the northwest, countries can expect an increase in flooding during winter, rising sea levels and warmer summers. Southern countries will experience rising temperatures, an increased risk of drought and lower crop yields as well as a reduction in arable land. Climate change in the north is likely to bring warmer, drier summers; extreme storms; rising sea levels and an increase in pests. Eastern countries will experience an increased risk of soil erosion, rainier summers and floods during the winter.