Fig. 2
From: County-level CO2 emissions and sequestration in China during 1997–2017
Test results for the mean pixel values in 2013. Data represent (a) the results with the supplementary input parameters based on the particle swarm optimization-back propagation (PSO-BP) algorithm, (b) the results with only the mean pixel values of nighttime light values based on the PSO-BP algorithm, (c) the results with the supplementary input parameters based on the BP algorithm, and (d) the results with only the mean pixel values of nighttime light values based on the BP algorithm.
