## Abstract

The equatorial coastal circulation is modeled in terms of the linear wave response to a diurnally oscillating heat source gradient in a background wind. A diurnal scaling shows that the solution depends on two parameters: a nondimensional coastal width L and a nondimensional wind speed U. The solutions are interpreted by comparing to the U = 0 theory of Rotunno. For U ≠ 0 the Fourier integral solution consists of three distinct wave branches. Two of these branches correspond to the prior no-wind solution of Rotunno, except with Doppler shifting and associated wave dispersion. The third branch exists only for U ≠ 0 and is shown to be broadly similar to flow past a steady heat source or a topographic obstacle. The relative importance of this third branch is determined largely by the parameter combination U/L. For sufficiently large U/L the third branch becomes the dominant part of the solution. The spatial structures of the three branches are described in terms of group velocity arguments combined with a desingularized quadrature method.

Original language | English (US) |
---|---|

Pages (from-to) | 1749-1763 |

Number of pages | 15 |

Journal | Journal of the Atmospheric Sciences |

Volume | 66 |

Issue number | 6 |

DOIs | |

State | Published - Sep 10 2009 |

## All Science Journal Classification (ASJC) codes

- Atmospheric Science