Future evolutions of net ecosystem production in the Northern high latitudes and its socioeconomic impacts

Abstract:

With the launch of the recent field campaigns such as the Arctic-Boreal Vulnerability Experiment (ABoVE), there is an unprecedent opportunity and urgent need to further optimize our estimates of Arctic carbon budget and to evaluate socioeconomic impacts due to high-latitude ecosystem changes. A key prerequisite is to quantify and understand the existing net ecosystem production (NEP) estimates. In this study, we analyzed the NEP estimates in the Northern high latitudes from the Coupled Model Intercomparison Project Phase-6 (CMIP6) projections in the 21^st century under different combinations of Representative Concentration Pathways (RCPs) and Shared Socioeconomic Pathways (SSPs), including SSP1-RCP2.6, SSP2-RCP4.5, SSP3-RCP7.0 and SSP5-RCP8.5. We then linked the NEP estimates with an integrated assessment model (the Global Change Assessment Model, GCAM) to facilitate the analysis of socioeconomic impacts of the changes of Northern high-latitude ecosystem carbon fluxes. Our analysis reveals large uncertainties in NEP estimates by CMIP6 models. Such uncertainties will keep relatively constant SSP1-RCP2.6, but will be getting larger under SSP2-RCP4.5, SSP3-RCP7.0 and SSP5-RCP8.5. The GCAM analysis indicates nonnegligible impacts of high latitude ecosystem NEP changes on the future global land and energy use.