...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Geophysical Research. Biogeosciences >Contribution to the circulation climatology of the eastern equatorial Pacific: Lower-atmospheric jets
【24h】

Contribution to the circulation climatology of the eastern equatorial Pacific: Lower-atmospheric jets

机译：对赤道东太平洋环流气候的贡献：低气压射流

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Novel data sets have been evaluated to reappraise the annual cycle of atmospheric circulation over the Pacific. In the eastern Pacific, cross-equatorial surface winds from the southern hemisphere generate an oceanic cold tongue immediately to the south of the equator. The associated lower-tropospheric thickness pattern entails a minimum of absolute topography in the midtroposphere near the equator, and together with the small Coriolis parameter this causes a jet stream of up to 10 ms(-1) at 700-600 mbar centered at 0 degrees-2 degrees N. The jet is most intense in late boreal winter because then the near-equatorial surface low-pressure trough is flat. The jet is fed by lower-tropospheric convergence over equatorial South America and by upper tropospheric convergence and subsidence over a narrow equatorial zone of the eastern Pacific. Over the central Pacific a jet of up to 10 ms(-1) is found at 10 degrees-12 degrees N and 925-850 mbar, while friction brakes the flow in the layer of steepest meridional pressure gradient near the surface. This lower-tropospheric jet, as the surface pressure gradient, is also strongest in late boreal winter. Overall, the NCEP analyses resolve the near-surface circulation less well than the long term ship observations. However, the midtropospheric equatorial jet over the eastern Pacific is also borne out by the 1967-1971 radiosoundings over Galapagos, and the lower-tropospheric trade wind jet over the central Pacific was also identified from the intense radiosonde program of the March-April 1967 Line Islands Experiment. [References: 29]
机译：对新的数据集进行了评估，以重新评估太平洋上空的年度循环。在东太平洋，来自南半球的赤道表面风直接在赤道以南产生海洋冷舌。相关的低对流层厚度模式需要在赤道附近的对流层中具有最小的绝对地形，并且与小的Coriolis参数一起会导致以0度为中心的700-600 mbar时高达10 ms（-1）的射流-2度N。在北半球冬季后期，射流最强烈，因为此时近赤道表面的低压槽是平坦的。赤道南美洲上空的对流层低层汇合，东太平洋狭窄的赤道区上空对流层汇聚和下沉，为射流供气。在太平洋中部，在北纬10度至12度和925-850 mbar处发现高达10 ms（-1）的射流，而摩擦力则使表面附近最陡的经向压力梯度层中的流动制动。这种低对流层射流作为表面压力梯度，在寒冬后期也最强。总体而言，NCEP分析解决近地表环流问题的能力不及长期船舶观测结果。但是，1967年至1971年加拉帕戈斯上空的无线电探空也证实了东太平洋上空的对流层赤道急流，1967年3月至4月线的强探空仪计划也确定了中太平洋上空的对流层低空贸易风离岛实验。 [参考：29]

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号