Quantifying rates and drivers of change in long-term sector- and country-specific trends of carbon dioxide-equivalent greenhouse gas emissions

Significance, direction, rate, and drivers of change in total carbon dioxide -equivalent (CO2-eq.) greenhouse gas (GHG) (GHGCO2−e) emission from eight sectors of 41 Annex-I countries were quantified over the period of 1990-2012 using data-driven models. The Mann-Kendall (MK) test for trend analysis indicated an overall downward trend by 10.5% with a Sen's slope of −613 Mt CO2-eq./year. The highest GHGCO2−e emission growth and reduction occurred with the sectors of energy, and land use, land use change and forestry (LULUCF) at rates of 1.2 and −1.0 gigatons (Gt) CO2-eq./year, respectively. Out of the 41 countries, 18 (44%) and 12 (29%) significantly reduced and increased their GHGCO2−e emission rates, respectively (p<0.1). The best-fit multiple non-linear regression (MNLR) model as a function of population density, gross domestic product per capita, fractional contribution of renewable energy to total energy production, country, and year elucidated 99.8% of variation in total GHGCO2−e emission and had the predictive power of 99.8% based on leave-one-out cross-validation.