Thermal regime in the troposphere, stratosphere, and mesosphere of the northern polar zone in 1979–2019

Abstract

Changes of the thermal regime in the troposphere, stratosphere, and mesosphere of the northern polar zone (68–90? N) during 1979–2019 were studied using the data on average monthly air temperatures at the nodes of a regular geographical grid of 1? × 1? on 51 isobaric surfaces (ERA5 reanalysis). The mean and standard deviations, normalized anomalies and linear temperature trends, low-frequency components up to an altitude of 80 km were calculated. The obtained statistical characteristics were analyzed to assess the intensity of climate warming in the Arctic troposphere and cooling in the stratosphere and mesosphere, as well as to reveal correlations between the neighboring levels. The features of spring rearrangements of the stratospheric circulation were considered in relation to solar activity and sudden stratospheric warmings under polar night conditions. It was shown that the Arctic oscillation most effectively influences the air temperature of the lower stratosphere in winter.

Keywords

• air temperature
• linear trend
• correlation dependence
• northern polar zone
• arctic
• spring restructuring of circulation