The linear stationary wave response to Arctic amplification related heating

Abstract

There has been a raft of manuscripts which claim to show that Arctic amplification (AA) is responsible for changes in the large-scale wintertime midlatitude atmospheric circulation. Responses to these studies have shown that the results are likely artifacts of the chosen methodology, but do not discount the potential influence of AA on the midlatitude circulation. Few have investigated the physical mechanisms that might link the anomalous heating to midlatitude circulation. In this investigation we employ a linear stationary wave model to investigate the hypothesis that AA, in the form of a low-level anomalous heating of the atmosphere, can drive a midlatitude circulation response. The model is well suited to the question due to its ability to reproduce the observed atmospheric circulation, and its simplicity as it requires only four forcing components plus the zonal mean state from reanalysis. Interpreting the model results is relatively straightforward. The results show that the AA related anomalous heating has a modest direct impact on the midlatitude circulation and a further investigations of possible nonlinear interactions and wave- mean flow interactions are needed.