Modelling the descent of nitric oxide during the elevated stratopause event of January 2013
Journal article, 2017

Using simulations with a whole-atmosphere chemistry-climate model nudged by meteorological analyses, global satellite observations of nitrogen oxide (NO) and water vapour by the Sub-Millimetre Radiometer instrument (SMR), of temperature by the Microwave Limb Sounder (MLS), as well as local radar observations, this study examines the recent major stratospheric sudden warming accompanied by an elevated stratopause event (ESE) that occurred in January 2013. We examine dynamical processes during the ESE, including the role of planetary wave, gravity wave and tidal forcing on the initiation of the descent in the mesosphere-lower thermosphere (MLT) and its continuation throughout the mesosphere and stratosphere, as well as the impact of model eddy diffusion. We analyse the transport of NO and find the model underestimates the large descent of NO compared to SMR observations. We demonstrate that the discrepancy arises abruptly in the MLT region at a time when the resolved wave forcing and the planetary wave activity increase, just before the elevated stratopause reforms. The discrepancy persists despite doubling the model eddy diffusion. While the simulations reproduce an enhancement of the semi-diurnal tide following the onset of the 2013 SSW, corroborating new meteor radar observations at high northern latitudes over Trondheim (63.4°N), the modelled tidal contribution to the forcing of the mean meridional circulation and to the descent is a small portion of the resolved wave forcing, and lags it by about ten days.

Gravity waves

Middle atmospheric circulation

Stratospheric sudden warming

Planetary waves

Nitric oxide

Author

Y. J. Orsolini

University of Bergen

Norwegian Institute for Air Research (NILU)

V. Limpasuvan

Coastal Carolina University

Kristell Perot

Chalmers, Earth and Space Sciences, Global Environmental Measurements and Modelling

P. J. Espy

University of Bergen

Norwegian University of Science and Technology (NTNU)

Robert Hibbins

Norwegian University of Science and Technology (NTNU)

University of Bergen

Stefan Lossow

Karlsruhe Institute of Technology (KIT)

Katarina Raaholt Larsson

Donal Murtagh

Chalmers, Earth and Space Sciences, Global Environmental Measurements and Modelling

Journal of Atmospheric and Solar-Terrestrial Physics

1364-6826 (ISSN)

Vol. 155 50-61

Atmospheric Composition Changes Induced by Energetic Particle Precipitation

Swedish National Space Board, 2016-01-01 -- 2019-12-31.

Roots

Basic sciences

Infrastructure

Onsala Space Observatory

Subject Categories

Climate Research

DOI

10.1016/j.jastp.2017.01.006

More information

Latest update

9/26/2018