Project deliverable Open Access
Liu, Yang; Attema, Jisk
Meridional Energy Transport (MET), both in the atmosphere (AMET) and ocean (OMET), has significant impact on the climate in the Arctic. In this study, the quantification of atmospheric meridional energy transport (AMET) and oceanic meridional energy transport (OMET) at subpolar latitudes have been performed using six state-of-the-art reanalyses datasets (ERA-Interim, MERRA2, JRA55, ORAS4, GLORYS2V3, and SODA3). Emphasis is placed on the key processes regulating AMET and OMET from midlatitudes to the Arctic. The differences between these data sets were investigated. A forced NEMO-ORCA hindcast, two high resolution fully coupled HadGEM3-GC3.1 simulations and observations in the Atlantic from Rapid Climate Change-Meridional Overturning Circulation and Heatflux Array (RAPID ARRAY) and Overturning in the Subpolar North Atlantic Program (OSNAP) are included in the comparison. Based on the intercomparison of reanalyses data, model outputs and the observation data, sources of uncertainty are identified. The impacts of orography on the atmospheric moisture and heat transport toward the pole were studied with the IPSL-CM6 model experiments. Compensation and feedback between oceanic and atmospheric heat, moisture or energy transport impacts on the Arctic variability were checked with the CESM1 Large Ensemble simulations and the MPI-ESM-LR grand ensemble simulations (MPI-GE), which also reflect the respective role of the natural climate variability and externally forced climate change. To support our comparison of AMET and provide more insight, we further investigate AMET with multiple atmospheric model simulations (EC-Earth, HadGEM, NorSEM, WACCM6, CMCC-CM, IPSL-CM, IAP-AGCM, MPIESM) from the coordinated experiments, in collaboration with Blue-Action WP3 “Linkages of Arctic climate changes to lower latitudes”.
The main results are: