Fig. 6: Contribution of irrigation energy input intensity to total energy input intensity and comparison of CO2 emissions intensity generated by energy inputs intensity during 2000–2010.
From: Global energy use and carbon emissions from irrigated agriculture
a Energy inputs intensity comes from irrigation, fertilizers (N, P2O5, and K2O) production and transport, machinery (includes tractors, harvesters, and threshers15) manufacturing, and fuel consumption of machines. b Besides GHG emissions generated by the four energy inputs, soil emissions from N fertilizers use are considered. The useful life of machinery is assumed to be a 20-year average. The fuel used in the machinery mainly considers liquefied petroleum gas, motor gasoline, and gas-diesel oils. Other greenhouse gas emissions (e.g. CH4 and N2O) generated by energy inputs are converted to carbon dioxide equivalents (CO2e), using global warming potential (GWP) values of the IPCC AR5 with no climate feedback (GWP-CH4 = 28; GWP-N2O = 265)68.
