第22回 ESCセミナー
Adventures with the Solar Barometric Tide
- 日時
- 2006年12月13日 (水) 14:00-15:00
- 場所
- 横浜研究所 地球シミュレータ研究棟1階 大会議室
- 講演者
- Kevin P. Hamilton (International Pacific Research Center and Department of Meteorology, University of Hawaii at Manoa)
- 使用言語
- 英語
要旨
The diurnal cycle of radiation forces a large-scale wavelike response that propagates both zonally and vertically. The forcing and the response can both be conveniently resolved into diurnal (24-hour), semidiurnal (12-hour), terdiurnal (8-hour) etc. harmonics. These so-called atmospheric thermal tides are most easily observed at the ground by analysis of hourly barometric observations. The diurnal and semidiurnal surface barometric oscillations, denoted S1(p) and S2(p), respectively, have been determined at very large numbers of stations throughout the world.
The semidiurnal tide is effectively a global-scale inertia-gravity wave that is forced mainly by solar heating in the ozone layer. This talk will deal with two aspects of the semidiurnal tide, focusing on its surface expression as S2(p). First the simulation of the semidiurnal tide within comprehensive global atmospheric GCMs is reviewed, starting with the early work of Zwiers and Hamilton (1986) and Tokioka and Yagai (1987). I will then argue that, perhaps paradoxically given the global scale forcing of the tide, there are advantages to analyzing S2(p) in very-fine resolution GCMs. I will then show how fine-resolution AFES global model simulations together with observational analyses can be used to investigate the topographic effects on S2(p).
Finally earlier studies of the variability of S2(p) will be reviewed and my new work looking at the effects of the 27-day solar cycle on S2(p) will be described.
問い合わせ先
地球シミュレータセンター大淵 済
Phone : 045-778-5765
FAX : 045-778-5492
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