Estimating spatiotemporal dynamics of evapotranspiration and assessing the cause for its increase in China

•37-year monthly E based on the optimality principle was estimated in China.•In the northwest, south, and center, E was controlled by water, energy, and LAI.•Different attribution methods lead to inconsistent dominant factors for E trends.•LAI-induced E increase and CO2-induced E decrease had opposite trends along aridity.