Interannual variability in the Northern Hemisphere winter middle atmosphere in control and perturbed experiments with the GFDL SKYHI general circulation model
- Princeton Univ., Princeton, NJ (United States)
This paper reports on interannual variability of the Northern Hemisphere winter stratospheric circulation as simulated by the 40-level Geophysical Fluid Dynamics Laboratory (GFDL) `SKYHI` general circulation model. A 31-year control simulation was performed using a climatological annual cycle of sea surface temperatures. The interannual variability of the stratospheric circulation in this model has some realistic features. In particular, the simulated variance of monthly mean, zonal-mean temperature and wind in the extratropical Northern Hemisphere agrees fairly well with observations. The day-to-day variability of the circulation also appears to be rather well simulated, with midwinter warmings of realistic intensity and suddenness appearing in the polar regions. The major deficiency is the absence of a realistic quasi-biennial oscillation (QBO) in the simulated winds in the tropical lower stratosphere. There is also an indication of long period (approximately 10 year) variability in the winter polar vortex. This appears not to be related to any obvious source of long-term memory in the atmosphere such as surface boundary conditions or the flow in the tropical stratosphere. The model has also been run through a large number of boreal winter simulations with imposed perturbations.
- OSTI ID:
- 53464
- Journal Information:
- Journal of the Atmospheric Sciences, Journal Name: Journal of the Atmospheric Sciences Journal Issue: 1 Vol. 52; ISSN 0022-4928; ISSN JAHSAK
- Country of Publication:
- United States
- Language:
- English
Similar Records
The solar and equatorial QBO influences on the stratospheric circulation during the early northern-hemisphere winter. [Quasi-Biennial Oscillation]
Improved Simulation of the QBO in E3SMv1