科氏效應與環境風場對海風環流之影響

Effects of Coriolis Force and Ambient Wind on Sea Breeze Circulations

侯昭平(Jou-Ping Hou) ； 許武榮(Wu-Ron Hsu) ； 吳清吉(Ching-Chi Wu) ； 謝銘恩(Ming-En Hsieh) ； 戴志輝(Jyh-Huei Tai) ； 林裕豐(Yu-Feng Lin)

《大氣科學》 34卷4期 (2006/12) Pp. 335-351

摘要

The NTU/Purdue nonhydrostatic model is applied to study the effects of Coriolis force and the ambient wind speed on sea breeze circulations with a very high spatial resolution. We found that Coriolis force plays a very important role in the development of a sea breeze circulation. The direction of sea breeze is deflected with a weaker intensity and shorter distance of inland penetration by including the effect of earth's rotation in the model. However, the turbulence inside the convective boundary layer ahead of the sea breeze circulation remained unaffected.
With an on-shore (same direction as the embedded sea breeze) wind speed, the sea breeze can penetrate farther inland and the surface heat flux behind the sea breeze front can be stronger with a strong wind speed near the ground surface. With an off-shore ambient wind speed, the process of merging of the sea breeze front and large eddies inside the inland convective boundary layer becomes very pronounced. The time scale of the merging process is much shorter with an off-shore ambient wind than the on-shore situation. However, when the ambient wind speed is too strong, the sea breeze circulation cannot develop at all.

關鍵字

科氏效應 ； 海風鋒面 ； 對流邊界層

並列摘要

The NTU/Purdue nonhydrostatic model is applied to study the effects of Coriolis force and the ambient wind speed on sea breeze circulations with a very high spatial resolution. We found that Coriolis force plays a very important role in the development of a sea breeze circulation. The direction of sea breeze is deflected with a weaker intensity and shorter distance of inland penetration by including the effect of earth's rotation in the model. However, the turbulence inside the convective boundary layer ahead of the sea breeze circulation remained unaffected.
With an on-shore (same direction as the embedded sea breeze) wind speed, the sea breeze can penetrate farther inland and the surface heat flux behind the sea breeze front can be stronger with a strong wind speed near the ground surface. With an off-shore ambient wind speed, the process of merging of the sea breeze front and large eddies inside the inland convective boundary layer becomes very pronounced. The time scale of the merging process is much shorter with an off-shore ambient wind than the on-shore situation. However, when the ambient wind speed is too strong, the sea breeze circulation cannot develop at all.

並列關鍵字

Coriolis effect ； Sea-breeze front ； Convective boundary layer