Instructor: Professor E. S. Sarachik
114
King Bldg., 543-6720
sarachik@atmos.washington.edu
Lectures:MW, 1:30 - 2:50, 406 ATG
This is a course in the observations and underlying dynamics of large-scale tropical circulations. The course concentrates on the factors that determine regions of large scale persistent precipitation in the tropics, the thermal forcing of atmospheric circulations by these regions, and the temporal variability of the forcing and response.
TOPICS:
1. Kinematics
qe,s,h,h*, buoyancy.
Vertical Structure in disturbed and undisturbed
regions.
Deep and shallow Convection.
How clouds affect the
environment--cumulus parameterization.
2. Observations
SST, SLP, Precip.: Mean and annually varying.
Divergence: Mean and annually varying.
OLR: Mean and annually
varying.
Surface Fluxes over the Ocean: Mean and annually varying.
Heat Transport by the Oceans and Surface Fluxes.
3. Wave Dynamics on a Equatorial b-plane
Single baroclinic mode (Matsuno).
Unbounded atmosphere (Lindzen).
4. Thermal Forcing in the Tropics.
Gill Model.
Lindzen-Nigam Model.
The Reed-Recker Wave.
Adiabatic Compensation: Observations and
dynamics.
5. Hadley Circulations.
Hyde's Theorem.
Role of Cumulus Friction.
Angular Momentum Conservation.
6. El Niño/Southern Oscillation.
Observations.
Current Theory.
Predictability.
7. Monsoonal Circulations.
Summer and Winter Monsoons.
8. Intraseasonal Variability.
30-60 day variability.
1. Kinematics
Sarachik, E.S., 1978: Tropical sea surface temperature: An inter-active one-dimensional atmosphere-ocean model, Dyn. Atmos.& Oceans., 2, 455-469.
Sarachik, E.S., 1985: A simple theory for the vertical structure of the tropical atmosphere, Pure and Appl. Geophys., 123, 261-271.
Yanai, M., S. Esbensen, and J-H Chu, 1973: Determination of bulk properties of tropical cloud clusters from large-scale heat and moisture budgets. J. At mos. Sci., 30, 611-627.
2. Observations
Hastenrath, S., 1985: "Climate and Circulation of the Tropics". D.Reidel Publishing Co., 455pp.
Hastenrath, S., 1980: Heat budget of tropical ocean and atmosphere. J. Phys. Oceanogr., 10, 159-170.
Hastenrath, S., 1982: On meridional heat transports in the world ocean. J. Phys. Oceanogr., 12, 922-927.
Oberhuber, J.M., 1988: "An atlas based on the 'COADS' data set: The budgets of heat, buoyancy, and turbulent kinetic energy at the surface of the global ocean." Max-Planck-Institut für Meteor-ologie Report No. 15, Hamburg.
Oort, A.H., 1983: Global Atmospheric Circulation Statistics, 1958-1973. NOAA Professional Paper No. 14, 180 pp. + 47 microfiche.
Reynolds, R.W., 1982: A monthly averaged climatology of sea surface temperature. NOAA Technical Report NWS 31, 35pp.
Wright, P.B., 1988: "An atlas based on the 'COADS' data set: Fields of mean wind, cloudiness, and humidity at the surface of the global ocean." Max-Planck-Institut für Meteorologie Report No. 14, Hamburg.
3. Wave dynamics on an Equatorial Beta Plane
Lindzen, R.D., 1967: Planetary waves on beta planes. Mon. Wea. Rev., 95, 441-451.
Matsuno, T., 1966: Quasi-geostrophic motions in the equatorial area. J. Met. Soc. Japan, 44, 25-42.
4. Thermal Forcing in the Tropics.
Gill, A.E., 1980: Some simple solutions for heat-induced tropical circulation. Quart. J. Roy. Met. Soc., 106, 447-462.
Lindzen, R.S., and S. Nigam, 1987: On the role of sea surface temperature gradients in forcing low level winds and conver-gence in the trop-ics. J. Atmos. Sci., 44, 2440-2458.
Reed, R.J., and R.E. Recker, 1971: Structure and properties of synoptic-scale wave disturbances in the equatorial western Pacific. J. Atmos. Sci., 28, 1117-1133.
5. Hadley Circulations.
Held, I.M., and A.Y. Hou, 1980: Nonlinear axially symmetric circu-lations in a nearly inviscid atmosphere. J. Atmos. Sci., 37, 515-533.
Schneider, E.K., and R.S. Lindzen, 1976. A discussion of the para-meterization of momentum exchange by cumulus convection. J. Geophys. Res., 81, 3158-3160.
Schneider, E.K., and R.S. Lindzen, 1977: Axially symmetric steady-state models of the basic state for instability and climate studies. Part I. Linearized calculations. J. Atmos. Sci., 34, 263-279.
Schneider, E.K., 1977: Axially symmetric steady-state models of the basic state for instability and climate studies. Part II. Nonlinear calculation. J. Atmos. Sci., 34, 280-296.
6. El Niño/Southern Oscillation.
Barber, R.T., and F.P. Chavez, 1983: Biological consequences of El Niño. Science, 222, 1203-1210.
Battisti, D.S., 1988: Dynamics and thermodynamics of a warming event in a coupled tropical atmosphere-ocean model. J. Atmos. Sci., 45, 2889-2919.
Battisti, D.S., and A.C. Hirst, 1988: Interannual variability in the tropical atmosphere/ocean system: influence of the basic state and ocean geometry. J. Atmos. Sci., 46, 1687-1712.
Battisti, D.S., A.C. Hirst, and E.S. Sarachik, 1989: Instability and predictability in coupled atmosphere-oceam models. Phil. Trans. Roy. Soc. Lond., A329, 237-247.
Cane, M.A., 1983: Oceanographic events during El Niño. Science, 222, 1189-1195.
Cane, M.A., 1986: El Niño. Ann.Revs. Earth Plan. Sci., 14, 43-70.
Philander, S.G.H., 1989: "El Niño, La Niña, and the Southern Oscillation", Academic Press.
Rasmusson, D.M., and T.H. Carpenter, 1982: Variations in tropical sea surface temperature and surface wind fields associated with the Southern Oscillation/El Niño. Mon. Wea. Rev., 110, 354-384.
7. Monsoonal Circulations.
Fein, J.S., and P.L. Stephens, 1987: "Monsoons," Wiley-Inter-science, 632 pp.
8. Intraseasonal Variability.
Madden, R.A., and P.R. Julian, 1971: Detection of a 40-50 day oscillation in the zonal wind in the tropical Pacific. J. Atmos. Sci., 28, 702-708.
Madden, R.A., and P.R. Julian, 1972: Description of global scale circulation cells in the tropics with a 40-50 day period. J. Atmos. Sci., 29, 1109-1123.
Madden, R.A., and P.R. Julian, 1994: Observations of the 40-50-Day Tropical Oscillation—A Review. Mon. Wea. Rev., 122, 814-837.