Climate change could devastate South American agriculture

Solve Climate: The melting of the Andean glaciers. Massive die-off of the Amazonian rainforests. Rising sea-levels and the inundation of low-lying regions on Colombia’s Caribbean coast. By now, this panorama is familiar to anyone who looks at the potential impacts of anthropogenic global warming on Latin America. Less familiar, though equally serious, is the damage climate change could wreak on the region’s agriculture.

The world’s total agricultural production could decrease between 3 percent and 15 percent due to global climate change, according to the World Bank. Studies suggest those numbers could be much worse in the agricultural regions of Latin America's equatorial belt. How severe the impact on agriculture gets will depend in part on the existence and the magnitude of the carbon fertilization effect. Carbon fertilization is an increase in crop growth due to greater atmospheric carbon interacting with sunlight through photosynthesis.

Analysts concede that a carbon fertilization effect likely won’t reach the levels many hoped for. As economist William Cline, who analyzes the effects of climate change on world agriculture, comments: "I think it would be extremely risky to assume that carbon fertilization is the solution to this problem.”

Keep in mind that Cline’s study and the World Bank analysis, which was partly based upon it, may still sharply underestimate agricultural losses. Neither deals with increased damage from pests or more severe weather conditions. Furthermore, Cline’s study used information from the 2001 IPCC baselines projections. But by now, the 2007 IPCC projections are considered overly conservative and very likely underplay the warming that will occur if greenhouse gas emissions continue on their current trajectory.…

The Pio XI Glacier in southern Chile, shot by Pierre cb, Wikimedia Commons