Book contents
- Frontmatter
- Contents
- Preface
- 1 Overview
- 2 Governing equations for mesoscale motions
- 3 Basic wave dynamics
- 4 Mesoscale wave generation and maintenance
- 5 Orographically forced flows
- 6 Thermally forced flows
- 7 Mesoscale instabilities
- 8 Isolated convective storms
- 9 Mesoscale convective systems
- 10 Dynamics of fronts and jet streaks
- 11 Dynamics of orographic precipitation
- 12 Basic numerical methods
- 13 Numerical modeling of geophysical fluid systems
- 14 Parameterizations of physical processes
- Appendices
- Index
- References
6 - Thermally forced flows
Published online by Cambridge University Press: 15 December 2009
- Frontmatter
- Contents
- Preface
- 1 Overview
- 2 Governing equations for mesoscale motions
- 3 Basic wave dynamics
- 4 Mesoscale wave generation and maintenance
- 5 Orographically forced flows
- 6 Thermally forced flows
- 7 Mesoscale instabilities
- 8 Isolated convective storms
- 9 Mesoscale convective systems
- 10 Dynamics of fronts and jet streaks
- 11 Dynamics of orographic precipitation
- 12 Basic numerical methods
- 13 Numerical modeling of geophysical fluid systems
- 14 Parameterizations of physical processes
- Appendices
- Index
- References
Summary
Some of the basic dynamics of a number of thermally forced flows can be understood by using a known function to represent diabatic heating or cooling. For example, in theoretical studies of sea breeze circulations, the differential heating associated with the land–sea temperature contrast is prescribed as a periodic function at the ground level. This approach makes the mathematical problem more tractable and applicable to other problems related to mesoscale circulations. These problems include heat island circulations, sea and land breezes, mountain-plain solenoidal circulations, density current generation and propagation, formation of thunderstorm cloud tops, as well as circulations and gravity waves that are generated by diabatic heating associated with coastal frontogenesis, moist convection, and orographic precipitation systems.
In this chapter, we will discuss the problems listed above and will place a greater emphasis on the basic dynamics involved. Section 6.1 details the responses of a uniform, steady, continuously stratified flow to a mesoscale heat source or sink. This will make the fundamental dynamics easier to understand. This section will also discuss sinusoidal and isolated heat sources, transient flow response to a mesoscale heat source, pulse heating and steady heating. In addition, this section will include applications of the thermally forced circulation theory to various types of mesoscale circulations. In Section 6.2, we will discuss three-dimensional flow and shear flow over heat sources or sinks. Sections 6.1 and 6.2 will aid in understanding the dynamics of sea and land breezes. Mountain–plain solenoidal circulations are discussed in Sections 6.3 and 6.4.
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- Information
- Mesoscale Dynamics , pp. 184 - 228Publisher: Cambridge University PressPrint publication year: 2007