{"id":4107,"date":"2022-09-20T16:25:10","date_gmt":"2022-09-20T08:25:10","guid":{"rendered":"https:\/\/www.weather.org.hk\/blog\/?p=4107"},"modified":"2023-04-08T11:35:16","modified_gmt":"2023-04-08T03:35:16","slug":"%e9%9b%b7%e6%9a%b4%e7%9b%b8%e9%97%9c%e5%bc%b7%e9%99%a3%e9%a2%a8%e7%9a%84%e9%a0%90%e5%a0%b1%e6%96%b9%e6%b3%95","status":"publish","type":"post","link":"https:\/\/www.weather.org.hk\/news\/%e9%9b%b7%e6%9a%b4%e7%9b%b8%e9%97%9c%e5%bc%b7%e9%99%a3%e9%a2%a8%e7%9a%84%e9%a0%90%e5%a0%b1%e6%96%b9%e6%b3%95\/","title":{"rendered":"\u96f7\u66b4\u76f8\u95dc\u5f37\u9663\u98a8\u7684\u9810\u5831\u65b9\u6cd5"},"content":{"rendered":"

\u904e\u53bb\u7684\u661f\u671f\u65e5\uff0c\u672c\u6e2f\u53d7\u72c2\u98a8\u96f7\u66b4\u5f71\u97ff\uff0c\u591a\u8655\u51fa\u73fe\u731b\u70c8\u9663\u98a8\uff08\u5176\u4e2d\u5927\u6fb3\u53ca\u6d41\u6d6e\u5c71\u6700\u9ad8\u9663\u98a8\u5206\u5225\u9054\u6bcf\u5c0f\u6642110\u53ca93\u516c\u91cc\uff09\uff0c\u4e0d\u5c11\u6236\u5916\u6d3b\u52d5\u4eba\u58eb\u88ab\u56f0\u81f4\u96fb\u6c42\u52a9\uff0c\u4e00\u540d\u5728\u897f\u8ca2\u9032\u884c\u7368\u6728\u821f\u6d3b\u52d5\u7684\u4eba\u58eb\u66f4\u56e0\u800c\u6b7b\u4ea1\u3002\uff08\u90e8\u5206\u9032\u884c\u7368\u6728\u821f\u6d3b\u52d5\u4eba\u58eb\u62cd\u651d\u5f71\u7247<\/a>\uff09<\/p>\n

\u5929\u6587\u53f0\u9810\u6e2c\u6709\u967d\u5149\u53ca\u9a5f\u96e8\u751a\u81f3\u96f7\u66b4\u7684\u65e5\u5b50\uff0c\u8868\u793a\u5927\u6c23\u4e0d\u7a69\u5b9a\uff0c\u6236\u5916\u6d3b\u52d5\u8981\u7559\u610f\u5929\u6c23\u8b8a\u5316\uff0c\u8a08\u5283\u884c\u7a0b\u6642\u61c9\u907f\u514d\u9078\u64c7\u904e\u65bc\u7a7a\u66e0\u7684\u8def\u7dda\uff08\u884c\u5c71\u6216\u6c34\u4e0a\u6d3b\u52d5\uff09\uff0c\u4e26\u4ee5\u9632\u5929\u6c23\u8f49\u5dee\u6642\u53ef\u4ee5\u76e1\u5feb\u8eb2\u907f\u3002\u7531\u65bc\u9a5f\u96e8\u53ca\u96f7\u66b4\u767c\u5c55\u53ef\u4ee5\u76f8\u7576\u8fc5\u901f\uff0c\u73fe\u6642\u79d1\u6280\u7121\u6cd5\u6e96\u78ba\u9810\u6e2c\u5f71\u97ff\u4f4d\u7f6e\u53ca\u7bc4\u570d\uff0c\u56e0\u6b64\u5982\u6d3b\u52d5\u9032\u884c\u4e2d\u6642\u767c\u73fe\u5929\u8272\u8f49\u6697\u6216\u6709\u5fae\u96e8\u3001\u98a8\u5411\u8f49\u8b8a\u3001\u98a8\u901f\u589e\u5f37\u3001\u6d77\u6d6a\u589e\u5927\u7b49\u73fe\u8c61\u6642\uff0c\u5c31\u8981\u7acb\u5373\u4e0b\u5c71\u6216\u4e0a\u5cb8\uff0c\u4e0d\u61c9\u62b1\u50e5\u5016\u5fc3\u614b\u7e7c\u7e8c\u3002<\/p>\n

\u7576\u9999\u6e2f\u5883\u5167\u53ef\u80fd\u53d7\u96f7\u66b4\u5f71\u97ff\u6642\uff0c\u5929\u6587\u53f0\u5c31\u6703\u767c\u51fa\u96f7\u66b4\u8b66\u544a\uff0c\u4e26\u5728\u9069\u7576\u6642\u5019\u52a0\u5165\u9663\u98a8\u9810\u5831\uff0c\u4f8b\u5982\u300c\u9810\u6599\u9ad8\u9054\u6bcf\u5c0f\u6642 70 \u516c\u91cc\u6216\u4ee5\u4e0a\u7684\u5f37\u9663\u98a8\u5c07\u5439\u8972\u9999\u6e2f\u300d \u30022020\u5e74\u958b\u59cb\uff0c\u5047\u5982\u9810\u5831\u9663\u98a8\u905410\u7d1a\uff08\u6bcf\u5c0f\u664288\u516c\u91cc\uff09\u6216\u4ee5\u4e0a\uff0c\u5929\u6587\u53f0\u6703\u4f7f\u7528\u300c\u731b\u70c8\u9663\u98a8\u300d\u53ca\u300c\u5f37\u70c8\u72c2\u98a8\u96f7\u66b4\u300d\u7684\u5b57\u773c\u3002<\/p>\n

\u96f7\u66b4\u70ba\u751a\u9ebc\u6703\u5e36\u4f86\u9663\u98a8\uff1f\u53ef\u4ee5\u7528\u4e00\u500b\u6982\u5ff5\u6a21\u5f0f\u8868\u793a\uff1a<\/p>\n

<\/p>\n

\u96e8\u6ef4\u5728\u9ad8\u7a7a\uff08wet-bulb freezing level\uff09 \u56e0\u84b8\u767c\u4ee4\u6c23\u6eab\u4e0b\u964d\uff0c\u7a7a\u6c23\u5bc6\u5ea6\u589e\u52a0\u4e26\u5411\u4e0b\u6c89\uff08buoyancy\uff09\uff0c\u52a0\u4e0a\u96e8\u6ef4\u7684\u8f09\u91cd\uff08precipitation loading\uff09\u53ca\u9ad8\u7a7a\u98a8\u901f\uff08initial momentum\uff09\uff0c\u4e09\u8005\u7684\u7e3d\u548c\u5230\u9054\u5730\u9762\u5c31\u6210\u70ba\u9663\u98a8\uff0c\u7528\u516c\u5f0f\u8868\u793a\uff1a<\/p>\n

(1)<\/p>\n

<\/p>\n

VS \u53ca VH \u5206\u5225\u662f\u5730\u9762\u53ca\u9ad8\u7a7a\u98a8\u901f
UBUOY \u662f\u6d6e\u529b\uff08\u5411\u4e0b\u70ba\u6b63\uff09
ULOAD \u662f\u96e8\u6ef4\u8f09\u91cd<\/p>\n

\u53ea\u8981 UBUOY+ULOAD\uff1e\uff10\uff0c\u5c31\u6703\u51fa\u73fe\u4e0b\u6c89\u6c23\u6d41\uff08downdraft\uff09\uff0c\u5047\u5982\u6c23\u6d41\u5f37\u52c1\u800c\u5feb\u901f\uff0c\u5247\u7a31\u70ba\u4e0b\u64ca\u66b4\u6d41\uff08downburst\uff09\uff0c\u5230\u9054\u5730\u9762\u6642\u5f62\u6210\u731b\u70c8\u9663\u98a8\u3002<\/p>\n

\u5929\u6587\u53f0\u9810\u5831\u9663\u98a8\u7684\u65b9\u6cd5\uff0c\u5c31\u662f\u5229\u7528\u4eac\u58eb\u67cf\u63a2\u7a7a\u53ca\u5929\u6c23\u96f7\u9054\u8cc7\u6599\uff0c\u8a55\u4f30(1) \u5f0f\u53f3\u908a\u7684\u503c\u3002<\/p>\n

<\/p>\n

\u5176\u4e2d UBUOY \u53ca VH \u7684\u503c\u53ef\u5229\u7528\u6eab\u71b5\u5716\uff08tephigram\uff09\u4f86\u8a55\u4f30\uff08\u4e0a\u5716\u6a59\u8272\u9762\u7a4d\u53ca\u5713\u5708\uff09 \uff0c\u800c ULOAD \u7684\u503c\u5247\u6839\u64da\u96f7\u9054\u63d0\u4f9b\u7684 VIL \uff08vertically integrated liquid water\uff09\u6578\u64da\u4f86\u8a55\u4f30\uff0c\u8a73\u7d30\u7b97\u6cd5\u7565\uff0c\u6709\u8208\u8da3\u7684\u670b\u53cb\u8acb\u770b\u9644\u4ef6\u3002<\/p>\n

\u5929\u6587\u53f0\u5229\u75282000-2006\u5e74\u51fa\u73fe\u6bcf\u5c0f\u664270\u516c\u91cc\u6216\u4ee5\u4e0a\u9663\u98a8\u7684\u96f7\u66b4\u500b\u6848\u5206\u70ba\u5169\u534a\u4f5c training data set \u53ca test data set\uff0c\u4e26\u9032\u884c\u9810\u5831\u53ca\u9a57\u8b49\uff0c\u521d\u6b65\u7d50\u679c\u5982\u4e0b\uff1a<\/p>\n

<\/p>\n

\u5716\u4e2d\u901a\u904e\u539f\u9ede\u768445\u5ea6\u659c\u7dda\u662f\u6700\u7406\u60f3\u7684\u7d50\u679c\uff0c\u4ee3\u8868\u9810\u5831\u503c=\u89c0\u6e2c\u503c\u3002\u4e0a\u5716\u7684\u9810\u5831\u503c\uff08\u85cd\u5708\uff09\u4f4d\u7f6e\u504f\u53f3\uff0c\u8868\u793a\u9663\u98a8\u88ab\u9ad8\u4f30\uff0c\u7d93\u53c3\u6578\u8abf\u6574\u5f8c\u8b8a\u6210\u7d05\u5708\uff0c\u8868\u73fe\u8f03\u70ba\u7406\u60f3\u3002<\/p>\n

\u9019\u500b\u6982\u5ff5\u6a21\u5f0f2007\u5e74\u958b\u59cb\u5728\u5929\u6587\u53f0\u5167\u90e8\u61c9\u7528\u3002\u7531\u65bc\u4eac\u58eb\u67cf\u63a2\u7a7a\u8cc7\u6599\u6bcf12\u5c0f\u6642\u4e00\u6b21\uff0c\u5f80\u5f80\u4e0d\u80fd\u53cd\u6620\u6700\u65b0\u60c5\u6cc1\uff0c\u65bc\u662f\u52a0\u5165\u6df1\u6c34\u57d7\u7684\u6c23\u6d41\u5256\u6790\u5100\uff08wind profiler\uff09\u6578\u64da\u4f5c\u70ba\u53c3\u8003\u3002\u7d93\u904e\u591a\u5e74\u767c\u5c55\uff0c\u73fe\u6642\u6a21\u5f0f\u5df2\u8b8a\u6210\u696d\u52d9\u904b\u4f5c\u7684\u4e00\u90e8\u5206\uff0c\u4e0d\u904e\u5929\u6587\u53f0\u672a\u6709\u767c\u8868\u6587\u737b\u8a0e\u8ad6\u6a21\u5f0f\u6700\u65b0\u8868\u73fe\u3002<\/p>\n

<\/p>\n

<\/p>\n

2009\u5e743\u67085\u65e5\u7684\u4f8b\u5b50<\/p>\n","protected":false},"excerpt":{"rendered":"

過去的星期日，本港受狂風雷暴影響，多處出現猛烈陣風（其中大澳及流浮山最高陣風分別達每小時110及93公里），不少戶外活動人士被困致電求助，一名在西貢進行獨木舟活動的人士更因而死亡。（部分進行獨木舟活動人士拍攝影片） 天文台預測有陽光及驟雨甚至雷暴的日子，表示大氣不穩定，戶外活動要留意天氣變化，計劃行程時應避免選擇過於空曠的路線（行山或水上活動），並以防天氣轉差時可以盡快躲避。由於驟雨及雷暴發展可以相當迅速，現時科技無法準確預測影響位置及範圍，因此如活動進行中時發現天色轉暗或有微雨、風向轉變、風速增強、海浪增大等現象時，就要立即下山或上岸，不應抱僥倖心態繼續。 當香港境內可能受雷暴影響時，天文台就會發出雷暴警告，並在適當時候加入陣風預報，例如「預料高達每小時 70 公里或以上的強陣風將吹襲香港」 。2020年開始，假如預報陣風達10級（每小時88公里）或以上，天文台會使用「猛烈陣風」及「強烈狂風雷暴」的字眼。 雷暴為甚麼會帶來陣風？可以用一個概念模式表示： 雨滴在高空（wet-bulb freezing level） 因蒸發令氣溫下降，空氣密度增加並向下沉（buoyancy），加上雨滴的載重（precipitation loading）及高空風速（initial momentum），三者的總和到達地面就成為陣風，用公式表示： (1) VS 及 VH 分別是地面及高空風速UBUOY 是浮力（向下為正）ULOAD 是雨滴載重 只要 UBUOY+ULOAD＞０，就會出現下沉氣流（downdraft），假如氣流強勁而快速，則稱為下擊暴流（downburst），到達地面時形成猛烈陣風。 天文台預報陣風的方法，就是利用京士柏探空及天氣雷達資料，評估(1) 式右邊的值。 其中 UBUOY 及 VH 的值可利用溫熵圖（tephigram）來評估（上圖橙色面積及圓圈） ，而…<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"advanced_seo_description":"","jetpack_seo_html_title":"","jetpack_seo_noindex":false,"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[50,42],"tags":[],"class_list":["post-4107","post","type-post","status-publish","format-standard","hentry","category-50","category-42"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.weather.org.hk\/news\/wp-json\/wp\/v2\/posts\/4107","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.weather.org.hk\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.weather.org.hk\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.weather.org.hk\/news\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.weather.org.hk\/news\/wp-json\/wp\/v2\/comments?post=4107"}],"version-history":[{"count":4,"href":"https:\/\/www.weather.org.hk\/news\/wp-json\/wp\/v2\/posts\/4107\/revisions"}],"predecessor-version":[{"id":4871,"href":"https:\/\/www.weather.org.hk\/news\/wp-json\/wp\/v2\/posts\/4107\/revisions\/4871"}],"wp:attachment":[{"href":"https:\/\/www.weather.org.hk\/news\/wp-json\/wp\/v2\/media?parent=4107"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.weather.org.hk\/news\/wp-json\/wp\/v2\/categories?post=4107"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.weather.org.hk\/news\/wp-json\/wp\/v2\/tags?post=4107"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}