Environmental and Political Factors Combine to Exacerbate Syrian Drought that Underpins Unrest

by Caroline Hays

Major climate events have social and political ramifications beyond their environmental impacts. In a recent study, Kelley et al. (2015) examine the extent of the drought in Syria that began in the winter of 2006/2007 and consider how it impacted the country socially and politically. The authors find that, although Syria has experienced several multiyear (three or more) droughts in the last 80 years, the most recent drought is the most extreme on record. Additionally, the authors note that three of the four most severe droughts recorded in Syria have taken place in the last 25 years. They connect the dots between anthropogenic climate effects, drought, agricultural collapse, and mass human migration, presenting a more comprehensive picture of a major climate event than is often shown. Continue reading

Current Cropland Area may be able to Meet Growing Biomass Demand through 2050

by Caroline Hays

With population growth and a growing middle class demanding more land-intensive products, especially meat, the ability of the world’s current cropland area to meet these demands is a pressing question. Studies have predicted that from 2005 to 2050, global agricultural production will need to approximately double. Cropland expansion to meet this growing demand has the negative consequences of decreasing biodiversity and releasing greenhouse gases. In a recent study, Mauser et al. (2015) note that sustainable agricultural intensification and optimal cropland allocation are preferred methods to cropland expansion for increasing biomass production There have been recent studies, however, that cast doubt on whether growing demand can be met without cropland expansion. Mauser et al. (2015) investigate the potential of cropland intensification to meet growing demand, taking into account a number of economic, societal, and technological factors in their estimates. They predict that, given multiple harvests and efficient land use decisions, the productivity of current cropland can, in fact, rise to meet projections of future demand. The authors find that 39% of the overall potential increase in productivity results from increasing the intensity of crop production, and 30% from redistributing crops across regions to their profit-maximizing locations. The major implications of this finding are that rising demand may not necessitate expansion of cropland area. Additionally, the authors’ model does not include genetically modified (GM) crops, and suggests therefore that GM crops are not necessary to meet growing demand. Continue reading

Combination of Heatwaves and Drought May Convert Carbon Sinks into Carbon Sources

by Caroline Hays

Droughts and heatwaves are becoming more common place and more severe. They impact the carbon and water cycles in terrestrial ecosystems, which affect the carbon sequestration capability of terrestrial ecosystems. As these extreme climate events become more common, their effects, both separately and together, on the atmospheric carbon balance will be important for accurately projecting global warming’s progression. Yuan et al. (2016) examined the effects of a heatwave and drought in Southern China in the summer of 2013. They found that this drought and heatwave were the most severe experienced in the last 113 years. These events significantly altered the carbon cycle in the region, decreasing carbon uptake enough to convert the region from its historical role as a carbon sink to a carbon source of nearly the same size during July and August of 2013. Continue reading

How Agricultural Intensification can Contribute to a more Favorable Agricultural Climate

by Caroline Hays

Food security is an ever growing concern in a world with an expanding population, an expanding demand for land-intensive meat production, and a finite amount of cropland. Crop productivity is a primary concern for food security and is largely affected by precipitation and temperature. Extreme temperatures caused by global warming and the subsequent climate change are a particular concern for crop productivity. In addition to global effects, local climate patterns are important for crop productivity. As it turns out, climate’s effects on crops are not a one way street: agricultural practices also exert their own influences on rainfall and temperature. Mueller et al. (2015) looked at this feedback loop in the US Midwest and found that cropland intensification has contributed to more desirable conditions for crops, leading to higher precipitation rates and more moderate extreme high temperatures. Continue reading