{"id":7816,"date":"2024-04-05T00:59:01","date_gmt":"2024-04-04T16:59:01","guid":{"rendered":"https:\/\/tommykwan.com\/blog\/?p=7816"},"modified":"2026-03-15T22:15:29","modified_gmt":"2026-03-15T14:15:29","slug":"whats-monsoon-wind-why-monsoon-blow-from-north-east-in-winter-and-southwest-in-summer","status":"publish","type":"post","link":"https:\/\/tommykwan.com\/blog\/aviation\/whats-monsoon-wind-why-monsoon-blow-from-north-east-in-winter-and-southwest-in-summer\/","title":{"rendered":"What’s Monsoon Wind ; Why Monsoon blow from north east in winter and southwest in summer?"},"content":{"rendered":"

Ref:<\/p>\n

https:\/\/www.hko.gov.hk\/en\/publica\/gen_pub\/files\/sms_Urdu.pdf<\/a><\/p>\n

https:\/\/www.hko.gov.hk\/en\/education\/weather\/meteorology-basics\/00010-geostrophic-wind.html<\/a><\/p>\n

https:\/\/www.hko.gov.hk\/en\/education\/weather\/monsoons\/00068-why-the-winter-monsoon-in-hong-kong-is-generally-called-the-northeast-monsoon.html<\/a><\/p>\n

<\/a><\/p>\n

https:\/\/www.hko.gov.hk\/en\/education\/weather\/monsoons\/00072-the-monsoons-and-climate-change.html<\/a><\/span><\/p>\n

 <\/p>\n

\u6240\u8b02\u5b63\u5019\u98a8\u5c31\u4fc2\u6703\u96a8\u8457\u5b63\u7bc0\u6539\u8b8a\u65e2\u98a8, \u4f46\u5149\u662f\u7814\u7a76\u5462\u500b\u5b63\u5019\u98a8\u65e2\u98a8\u5411\u90fd\u641e\u5de6\u6211\u7c92\u5e7e\u9418, \u56e0\u70ba\u80cc\u5f8c\u8b1b\u7dca\u65e2CONCEPT \u6709\u597d\u5e7e\u500b:<\/p>\n

    \n
  1. \u54a9\u53ebHigh pressure system, \u54a9\u53ebLow pressure system<\/li>\n
  2. \u54a9\u4fc2\u98a8<\/li>\n
  3. \u54a9\u53ebCoriolis effect (\u79d1\u91cc\u5967\u5229\u529b\/\u79d1\u79d1\u6c0f\u529b)<\/li>\n
  4. \u54a9\u53ebGeostrophic Wind (\u5730\u8f49\u98a8)<\/li>\n<\/ol>\n

     <\/p>\n

    \u60f3\u7c21\u55aeD\u5481\u7406\u89e3\u5c31\u8981\u80cc\u5c11\u5c11\u91ce (\u660e\u767d\u5c11\u5c11\u57fa\u672cCONCEPT)<\/p>\n

      \n
    1. High, Low pressure system \u662f\u76f8\u5c0d (relative) : compare one air mass with another one
      \n\u4ef2\u8981\u8a18\u5f97\u901a\u5e38\u51cd\u5c31\u4fc2\u6709\u9ad8\u58d3\u5340, \u71b1\u5c31\u4fc2\u6709\u4f4e\u58d3\u5340~<\/li>\n
    2. \u98a8\u5c31\u662fdue to two air mass has pressure difference and so the pressure gradient as well as the pressure gradient force (PGF) exist, then due to hydrodynamics<\/a>  (some physic, boring stuff), the air molecule at high pressure area tend to “flow to ” low pressure area to reach an equilibrium state, this movement (movement of air molecule hitting on object, say human), we can sense it and the it is referring to wind. \u518d\u7c21\u55ae\u5c31\u4fc2\u56e0\u70ba\u6709pressure difference induce PGF, \u6240\u4ee5\u7a7a\u6c23\u7c92\u5b50\u6d41\u52d5\u5c31\u6709\u98a8!<\/li>\n
    3. Coriolis effect is a finding that in northern hemisphere, when air mass travel long distance, it will deflect to right due to the earth is rotating!<\/li>\n
    4. Geostrophic Wind is talking about when the PGF is equal to Coriolis force, then the overall resultant force will parallel to isobar, and the air mass’s movement will same in direction as this resultant force – this is Geostrophic Wind in ideal case!
      \n\"\"
      \nSo, \u5be6\u969b\u7d50\u679c\u6703\u4fc2
      \n\"\"<\/li>\n<\/ol>\n

      \u6709\u5de6\u5462D\u57fa\u672c\u65e2\u77e5\u8b58\u6211\u5730\u5c31\u89e3\u91cb\u5230\u9ede\u89e3\u51ac\u5929\u4fc2\u9999\u6e2f\u6709\u6771\u5317\u5b63\u5019\u98a8, \u590f\u5929\u5c31\u4fc2\u897f\u5357\u98a8~<\/p>\n

      \u539f\u56e0\u4fc2\u51ac\u5929, \u5927\u9678\u76f8\u5c0d\u51cd (\u6240\u4ee5HIGH PRESSURE), \u800c\u9999\u6e2f\u4f4d\u7f6e\u5357\u6d77 (\u76f8\u5c0d\u6eab\u6696\u5c31\u6709LOW PRESSURE), \u904b\u7528HIGH TO LOW CONCEPT , \u52a0\u57cb\u771f\u5be6\u4e16\u754c\u6709\u5c71\u6709OBJ! \u540c\u57cb\u5730\u7403\u4fc2\u6709\u8f49! \u6240\u4ee5PGF \u88abFRICTION \u540cCORILOIS FORCE \u641e\u641e\u4e4b\u5f8c\u5c31\u8b8a\u5de6\u6240\u8b02\u65e2\u6771\u5317\u98a8~<\/p>\n

      \"\"<\/p>\n

      \"\"<\/p>\n

      Figure 1:  Dot lines are isobars. R is the vector sum of pressure gradient force (P), Coriolis force (C) and friction (F). Prevailing winds over the southern China is generally from the northeasterly in winter monsoon<\/p>\n

       <\/p>\n

      \u81f3\u65bc\u590f\u5929\uff0c\u56e0\u70ba\u6c34\u4fc2\u6bd4\u8f03\u597d\u5438\u71b1\uff0c\u800c\u590f\u5929\u5927\u9678\u9678\u5730\u5347\u6eab\u76f8\u5c0d\u5feb\uff0c\u6240\u4ee5\u5927\u9678\u71b1 (LOW), \u5357\u6d77\u76f8\u5c0d\u51b7 (HIGH), \u5730\u7403\u90fd\u4fc2\u6709\u8f49, \u53c8\u4fc2\u6709FRICTION, \u6240\u4ee5:<\/p>\n

      \"\"<\/p>\n

      \u5e0c\u671b\u7121\u7406\u89e3\u932f…\u8a13\u5f97~<\/p>\n","protected":false},"excerpt":{"rendered":"

      Ref: https:\/\/www.hko.gov.hk\/en\/publica\/gen_pub\/files\/sms_Urdu.pdf https:\/\/www.hko.gov.hk\/en\/education\/weather\/meteorology-basics\/00010-geostrophic-wind.html https:\/\/www.hko.gov.hk\/en\/education\/weather\/monsoons\/00068-why-the-winter-monsoon-in-hong-kong-is-generally-called-the-northeast-monsoon.html https:\/\/www.hko.gov.hk\/en\/education\/weather\/monsoons\/00072-the-monsoons-and-climate-change.html   \u6240\u8b02\u5b63\u5019\u98a8\u5c31\u4fc2\u6703\u96a8\u8457\u5b63\u7bc0\u6539\u8b8a\u65e2\u98a8, \u4f46\u5149\u662f\u7814\u7a76\u5462\u500b\u5b63\u5019\u98a8\u65e2\u98a8\u5411\u90fd\u641e\u5de6\u6211\u7c92\u5e7e\u9418, \u56e0\u70ba\u80cc\u5f8c\u8b1b\u7dca\u65e2CONCEPT \u6709\u597d\u5e7e\u500b: \u54a9\u53ebHigh pressure system, \u54a9\u53ebLow pressure system \u54a9\u4fc2\u98a8 \u54a9\u53ebCoriolis effect (\u79d1\u91cc\u5967\u5229\u529b\/\u79d1\u79d1\u6c0f\u529b) \u54a9\u53ebGeostrophic Wind (\u5730\u8f49\u98a8)   \u60f3\u7c21\u55aeD\u5481\u7406\u89e3\u5c31\u8981\u80cc\u5c11\u5c11\u91ce (\u660e\u767d\u5c11\u5c11\u57fa\u672cCONCEPT) High, Low pressure system \u662f\u76f8\u5c0d (relative) : compare one air mass with another one \u4ef2\u8981\u8a18\u5f97\u901a\u5e38\u51cd\u5c31\u4fc2\u6709\u9ad8\u58d3\u5340, \u71b1\u5c31\u4fc2\u6709\u4f4e\u58d3\u5340~ \u98a8\u5c31\u662fdue to two air mass has pressure difference and so the pressure gradient Read More<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[64,72],"tags":[],"class_list":["post-7816","post","type-post","status-publish","format-standard","hentry","category-aviation","category-meteorology"],"_links":{"self":[{"href":"https:\/\/tommykwan.com\/blog\/wp-json\/wp\/v2\/posts\/7816","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/tommykwan.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/tommykwan.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/tommykwan.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/tommykwan.com\/blog\/wp-json\/wp\/v2\/comments?post=7816"}],"version-history":[{"count":2,"href":"https:\/\/tommykwan.com\/blog\/wp-json\/wp\/v2\/posts\/7816\/revisions"}],"predecessor-version":[{"id":10391,"href":"https:\/\/tommykwan.com\/blog\/wp-json\/wp\/v2\/posts\/7816\/revisions\/10391"}],"wp:attachment":[{"href":"https:\/\/tommykwan.com\/blog\/wp-json\/wp\/v2\/media?parent=7816"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/tommykwan.com\/blog\/wp-json\/wp\/v2\/categories?post=7816"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/tommykwan.com\/blog\/wp-json\/wp\/v2\/tags?post=7816"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}