Polar Amplification in a Moist Energy Balance Model: A Structural Econometric Approach to Estimation and Testing

Poleward transport of atmospheric moisture and heat play major roles in the magnification of warming in poleward latitudes per degree of global warming, a phenomenon known as polar amplification (PA). We derive a time series econometric framework using a restricted vector error correction model (VECM) and an identification strategy to recover the parameters of a moist energy balance model (MEBM) similar to those in the recent climate science literature. This framework enables the climate econometrician to estimate and forecast temperature rise in latitude belts as cumulative emissions continue to grow as well as account for effects of increases in atmospheric moisture predicted by the Clausius-Clapeyron equation, which drives spatial non-uniformity in climate change. Non-uniformity is important for two reasons: climate change has unequal consequences that need to be better understood and amplification of temperatures in polar latitudes has a higher potential to trigger irreversible climate tipping points.