Carbon footprint (CF) refers to the direct or indirect emissions of carbon dioxide (CO2) and other Green House Gases (GHGs) expressed in terms of carbon dioxide equivalents (Wiedmann and Minx, 2007). This constitutes a vital environmental indicator to understand and quantify the main emission sources and aids as an effective tool for energy and environmental management. Greenhouse gases (GHG) gets into the atmosphere either due to natural sources or anthropogenic activities. Contribution by natural sources is very less and are neutralized due to the natural environmental processes, but a large quantity is generated from anthropogenic sources, which is accumulating  in the atmosphere. Intergovernmental Panel on Climate Change (IPCC) lists 17 greenhouse gases with different global warming potentials in 100 years of time horizon (IPCC, 1996). United Nations Framework Convention on Climate Change (UNFCCC) considers only Carbon dioxide (CO2), Methane (CH4), Nitrous oxide (N2O), Hydrofluorocarbons (HFCs), Perfluorocarbons (PFCs) and Sulphur hexafluoride (SF6) for accounting national GHG inventories (; UNFCCC, 1997).  Carbon footprint assessment for a region helps to determine the impact of human activities on the environment and global climate.  The major sectors and activities included in the inventory for estimating the carbon footprint are listed in Table 1. The current chapter focuses on quantification of carbon footprint in the domestic solid waste sector. Mismanagement of municipal solid waste is a vital source of anthropogenic greenhouse gases (GHG) such as methane (CH4), biogenic carbon dioxide (CO2) and non-methane volatile organic compounds (NMVOCs) etc., (Ramachandra 2009). Among these, Methane is considered as a potent Greenhouse gas (GHG) having global warming potential (GWP) 25 times greater than that of carbon dioxide and concentration of atmospheric methane is annually increasing at 1-2%, this necessitates quantification of carbon footprint in waste sector planning appropriate mitigation measures.

Table 1: Carbon footprint sector description

Major fraction (72 to 79%) of solid waste generated in Indian households is organic (Jha et al., 2008; Thitame et al., 2009; Ramachandra 2009, 2012). The quantity and composition of emission mainly depends on the quantity of organic waste and method of solid waste disposal. Indiscriminate disposal of waste without treatment (segregation of organic fraction and generating either energy or compost), produces GHG contributing to carbon footprint. Methane is produced during the anaerobic degradation or breakdown of organic waste or carbon dioxide during aerobic degradation or burning of waste.