LOGIN TO YOUR ACCOUNT

Username
Password
Remember Me
Or use your Academic/Social account:

CREATE AN ACCOUNT

Or use your Academic/Social account:

Congratulations!

You have just completed your registration at OpenAire.

Before you can login to the site, you will need to activate your account. An e-mail will be sent to you with the proper instructions.

Important!

Please note that this site is currently undergoing Beta testing.
Any new content you create is not guaranteed to be present to the final version of the site upon release.

Thank you for your patience,
OpenAire Dev Team.

Close This Message

CREATE AN ACCOUNT

Name:
Username:
Password:
Verify Password:
E-mail:
Verify E-mail:
*All Fields Are Required.
Please Verify You Are Human:
fbtwitterlinkedinvimeoflicker grey 14rssslideshare1
Lin, Hai; Derome, Jacques (2011)
Publisher: Co-Action Publishing
Journal: Tellus A
Languages: English
Types: Article
Subjects:
The setup process of Pacific–North American (PNA) pattern anomalies that last more than10 days and the role played therein by synoptic-scale transients are investigated using a T21,3-level quasi-geostrophic model. As there is no time-dependent forcing in the model, the lowfrequencyPNA anomalies are generated entirely by the internal dynamics. From a 300-winterintegration, 100 cases of positive PNA anomalies and 118 cases of negative PNA anomalieslasting at least 10 days are identified. The PNA composites reveal that 5 days before the setupof a positive (negative) PNA anomaly there is a negative (positive) height anomaly over Canada.This anomaly moves westward and stops over the North Pacific. It then intensifies and a wavetrain develops downstream. The roˆ le played by the synoptic-scale transients is explored byprediction experiments starting from day−5 (5 days before the appearance of a PNA anomaly).A 5-day average centered at day −5 is used to remove the synoptic-scale transients from theinitial state. The results indicate that even without these transients in the initial conditions, thesetup process of a positive PNA anomaly can be reproduced quite well. On the other hand,the setup of a negative PNA pattern cannot be predicted if the synoptic-scale transients areabsent from the initial conditions. In this case, the pattern evolves systematically, but differentlyfrom the way it evolves in the control run.DOI: 10.1034/j.1600-0870.1999.00011.x
  • The results below are discovered through our pilot algorithms. Let us know how we are doing!

    • Corti, S. and Palmer, T. N. 1997. Sensitivity analysis of atmospheric low-frequency variability. Q. J. Roy. Meteor. Soc. 123, 2425-2447.
    • Dole, R. M. and Gordon, N. D. 1983. Persistent anomalies of the extratropical Northern Hemisphere wintertime circulation: Geophysical distribution and regional persisnence characteristics. Mon. Wea. Rev. 111, 1567-1586.
    • Dole, R. M. 1986. The life cycles of persistent anomalies and blocking over the North Pacific. Adv. in Geophysics 29, 31-69.
    • Frederiksen, J. S. 1979. The eVect of long planetary waves on the regions of cyclogenesis. J. Atmos. Sci. 36, 195-204.
    • Green, J. S. A. 1977. The weather during July 1976: Some dynamical considerations of the drought. Weather 32, 120-126.
    • Hoskins, B. J., Simmons, A. J. and Andrews, D. G. 1977. Energy dispersion in a barotropic atmosphere. Q. J. Roy. Meteor. Soc. 103, 553-567.
    • Horel, J. D. and Wallace, J. M. 1981. Planetary scale atmospheric phenomena associated with the Southern Oscillation. Mon. Wea. Rev. 109, 813-829.
    • Klasa, M., Derome, J. and Sheng, J. 1992. On the interaction between the synoptic-scale eddies and the PNA teleconnection pattern. Beitr. Phys. Atmosph./Contrib. Atmos. Phys. 65, 211-222.
    • Kushnir, Y. and Wallace, J. M. 1989. Interaction of lowand high-frequency transients in forecast experiment with a general circulation model. J. Atmos. Sci. 46, 1411-1418.
    • Lin, H. and Derome, J. 1996. Changes in predictability associated with the PNA pattern. T ellus 48A, 553-571.
    • Lin, H. and Derome, J. 1997. On the modification of the high- and low-frequency eddies associated with the PNA anomaly: an observational study. T ellus 49A, 87-99.
    • Marshall, J. and Molteni, F. 1993. Toward a dynamical understanding of planetary-scale flow regimes. J. Atmos. Sci. 50, 1792-1818.
    • Mullen, S. L. 1987. Transient eddy forcing of blocking flows. J. Atmos. Sci. 44, 3-22.
    • Pandolfo, L. 1993. Observational aspects of the lowfrequency intraseasonal variability of the atmosphere in middle latitudes. Adv. Geophys. 34, 93-174.
    • Roads, J. O. 1987. Predictability in the extended range. J. Atmos. Sci. 44. 3495-3527.
    • Simmons, A. J., Wallace, J. M. and Branstator, G. W. 1983. Barotropic wave propagation and instability, and atmospheric teleconnection patterns. J. Atmos. Sci. 40, 1363-1392.
    • Wallace, J. M. and Gutzler, D. S. 1981. Teleconnections in the geopotential height field during the Northern Hemisphere winter. Mon. Wea. Rev. 109, 784-812.
  • No related research data.
  • No similar publications.

Share - Bookmark

Cite this article

Collected from