Lapse Rate Peculiarities in the Arctic from Reanalysis Data and Model Simulations

Monthly mean data of the ERA-Interim reanalysis (1979-2014) are used to estimate the lapse rate in the Northern Hemisphere high-latitude troposphere. The relationship between the lapse rate and surface air temperature T-s is analyzed in terms of interannual variability for different seasons. The study analyzes the ability of the HIRHAM5 regional climate model to simulate the features of lapse rate distribution in the Arctic troposphere and the parameter of its sensitivity to the variation in surface air temperature d/dT(s) that were derived from reanalysis data. The regional features of the link between the vertical stratification of tropospheric temperature and the Arctic Oscillation are revealed. The estimates obtained from reanalysis data and model simulations are especially significant as the Arctic climate has higher variability and sensitivity under global changes that is characterized by so called Arctic amplification.