Identification

Title

Tidal variations in the mesosphere and lower thermosphere before, during, and after the 2009 sudden stratospheric warming

Abstract

This work presents a comprehensive evaluation of tides in the mesosphere and lower thermosphere (MLT) of the Whole Atmosphere Community Climate Model with thermosphere-ionosphere eXtension (WACCMX) and data assimilation provided by the Data Assimilation Research Testbed (DART) ensemble Kalman filter. A total of 26 diurnal and semidiurnal tidal components are calculated using the latest hourly data assimilation cycling during January 12-March 15, 2009 time period. When averaged over this entire yaw cycle, most tidal components display a latitudinal and vertical structures similar to that observed by the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER). However, WACCMX + DART amplitudes of some diurnal tidal components are a factor of similar to 1.2-2 times smaller and the peak altitudes and latitudes are shifted compared to SABER. The amplitudes of semidiurnal tides are likewise underestimated in the model, as well as being shifted in altitude and latitude, and some wavenumbers are not captured. Daily tidal variations are calculated in the model and compared with SABER and Super Dual Auroral Radar Network (SuperDARN) radar observations. Both the model and the radars show an amplification of the migrating semidiurnal tide during the week following the peak SSW. Enhancements in nonmigrating diurnal tides are also shown around the SSW peak, which could be produced by the nonlinear interaction between migrating tides and planetary waves. This study finds that, despite using data assimilation to constrain model dynamics, more work is needed in order to accurately simulate the full tidal spectrum and responses to SSWs in the MLT region.

Resource type

document

Resource locator

Unique resource identifier

code

http://n2t.net/ark:/85065/d7wh2tc0

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

geoscientificInformation

Keywords

Keyword set

keyword value

Text

originating controlled vocabulary

title

Resource Type

reference date

date type

publication

effective date

2016-01-01T00:00:00Z

Geographic location

West bounding longitude

East bounding longitude

North bounding latitude

South bounding latitude

Temporal reference

Temporal extent

Begin position

End position

Dataset reference date

date type

publication

effective date

2021-03-01T00:00:00Z

Frequency of update

Quality and validity

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Conformity

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version of format

Constraints related to access and use

Constraint set

Use constraints

Limitations on public access

None

Responsible organisations

Responsible party

contact position

OpenSky Support

organisation name

UCAR/NCAR - Library

full postal address

PO Box 3000

Boulder

80307-3000

email address

opensky@ucar.edu

web address

http://opensky.ucar.edu/

name: homepage

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact