Black carbon and organic carbon emissions from wildfires in Mexico

Abstract

In Mexico, approximately 7,650 wildfires occur annually, affecting 263,115 hectares of land. In addition to their impact on land degradation, wildfires cause deforestation, damage to ecosystems and promote land use change; apart from being the source of emissions of toxic substances to the environment (i.e., hydrogen cyanide, black carbon and organic carbon).

Black carbon is a short-lived greenhouse pollutant that also promotes snow and ice melt and decreased rainfall; it has an estimated global warming potential close to 5000[1].

We present an estimate of the black carbon and organic carbon emissions from wildfires in Mexico from 2000 to 2012 using selected emission factors from the literature and activity data from local agencies. The results show average emissions of 5,955 Mg/year for black carbon and 62,085 Mg/year for organic carbon.

Black carbon emissions are estimated to be 14,888 Gg CO2 equivalent (CO2 eq) per year on average. With proper management of wildfires, such emissions can be mitigated. Moreover, improved air quality, conservation of ecosystems, improvement of visibility and maintenance of land use are a subset of the related co-benefits. Mitigating organic carbon emissions, which are ten times higher than black carbon emissions, would also prevent the morbidity and mortality impacts of toxic organics in the environment.

[1] The GWP is calculated as the ratio of the Absolute Global Warming Potential (AGWP) of a given gas to the AGWP of CO2. The AGWP has units of W-m^-2 yr g^-1