Evaluation of the SKYHI general circulation model using aircraft N2O measurements. 1: Polar winter stratospheric meteorology and tracer morphology

Journal Article · Sun May 01 04:00:00 EDT 1994 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/93JD02332· OSTI ID:6449315

Strahan, S E; Mahlman, J D ^[1]

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1. Princeton Univ., NJ (United States) NOAA Geophysical Fluid Dynamics Lab, Princeton, NJ (United States)

Winter polar stratospheric nitric oxide (N2O) measurements made during two NASA polar aircraft field campaigns are used to evaluate the dynamics of the Geophysical Fluid Dynamics Laboratory's 'SKYHI' general circulation model. SKYHI has 1 deg latitude by 1.2 deg longitude grid spacing and 40 vertical levels (up to 80 km) and precscribed N2O dissociation coefficients. The model has been integrated a total of 20 months, producing one Antarctic and two Artic winters. The climatologies of these winters are compared with the known northern and southern hemisphere climatologies and to the meteorological conditions durng the time of the field campaigns. The two Arctic SKYHI winters show considerable interannual variability. In the lower stratosphere, SKYHI realistically simulates the magnitude and variability of winds and temperatures both inside and outside the polar vortex and can produce a credible sudden warming. In the Antarctic the magnitude and variablity of winds and temperatures around the polar vortex are quite realistic, but inside the vortex, temperatures are too low. Flight data from each mission have been averaged together to produce a contour map showing N2O morphology in and around the vortex. Because the N2O distribution in the lower stratosphere is under dynamical control, the mean N2O field can be used to interpret the dynamics of the polar stratosphere. At the Arctic vortex edge, Airborne Arctic Stratospheric Experiment (AASE) data show large gradients of N2O on isentropic surfaces. SKYHI vortex edge gradients are nearly as large, and model mixing ratios between 400 and 500 K (potential temperature) are similar to the observations. In the Antarctic, model mixing ratios are too high everywhere and the edge gradients are flatter than the observed gradients. The comparison of mean N2O fields suggests realistic wave activity in the SKYHI Arctic winter but inadequate wave activity in the SKYHI Antarctic winter.

• OSTI ID: 6449315
• Journal Information: Journal of Geophysical Research; (United States), Journal Name: Journal of Geophysical Research; (United States) Vol. 99:D5; ISSN JGREA2; ISSN 0148-0227
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540110*
540120 -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
ANNUAL VARIATIONS
ARCTIC REGIONS
ATMOSPHERIC CIRCULATION
COMPUTER CODES
COMPUTERIZED SIMULATION
CRYOSPHERE
EARTH ATMOSPHERE
POLAR REGIONS
SIMULATION
STRATOSPHERE
TESTING
VALIDATION
VARIATIONS