我认为重要的是认为厄尔尼诺现象的一个组件的大规模全球atmospheric-oceanic现象称为厄尔尼诺南方涛动(ENSO)。ENSO成形波动的降雨,风、海流和海浪。他们天生很不规则。南方振荡(所以)首次发现吉尔伯特沃克爵士主持季节性平均压力和降雨大量世界各地的电台。他发现一个高压的空间格局是占主导地位的地区附近的南太平洋中部和低压澳大利亚和印度反向高点变成低点和低点到高点。所以是一种大气现象,另一方面,厄尔尼诺现象是一个海洋的过程。尽管如此,两种现象之间的相互联系是重要的,这样他们不能单独考虑,Bjerknes所指出的(1966)。ENSO的共同作用是导致澳大利亚的干旱和减少上升流南美洲西海岸的营养输送(灾难性的后果)。普遍认为有一个必要的ENSO事件的起始原料是普通赤道风贸易模式的颠覆,一个东风稳定风由于沃克细胞。跨越数千公里,西风爆发一次表演在几天或者几周内波传输能量出发向西,最终向极沿着南美洲西海岸,一些能量反射和辐射回东方。 See sketch below: ![enter image description here][1] The equatorial isopycnal depression moves eastward along the equator as a Kelvin wave until reaching the western coast of South America relatively unchanged. These are shallow water waves so the speed is just $c = \sqrt{g'D}$ where $D$ is the depth and $g'$ is the reduced gravity, so they travel at about $c = 2.5$m/s plus 10-20% because they are literally advected by the [Cromwell Undercurrent][2]. They transport large amounts of energy over vast distances, depositing it far away from the generation zone in the western Pacific Ocean. Namely, after arrival on the east Pacific coast the equatorial Kelvin wave energy degenerates into two coastal Kelvin waves propagating poleward, and into new diffuse [equatorial Rossby waves][3] radiating towards the west Pacific. It is this removal of energy from the Western pacific through the development of these complicated wave motions and other more subtle processes that eventually brings an ENSO event to an end (chicken and egg?). Because the energy is removed, the SST drops, the trade winds resume thus ending ENSO. Source: Regional Oceanography: An Introduction By Matthias Tomczak [1]: http://i.stack.imgur.com/PK9Hl.png [2]: https://en.wikipedia.org/wiki/Cromwell_Current [3]: //www.hoelymoley.com/questions/12/how-do-rossby-waves-in-the-ocean-form/521#521
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