暴雨灾害
暴雨災害
폭우재해
TORRENTIAL RAIN AND DISASTERS
2012年
3期
287-292
,共6页
雾%时间变化%气象条件%地形作用%九华山
霧%時間變化%氣象條件%地形作用%九華山
무%시간변화%기상조건%지형작용%구화산
fog day%temporal change%meteorological condition%topographic effect%Jiuhua Mountain
利用1991—2010年九华山不同海拔高度上的国家气象观测站及区域气象观测站资料,分析九华山雾日时间变化特征及其形成的气象条件。结果表明:近10年来,九华山山坡雾日年际变化较大,并逐年减少,山脚雾日逐年增多;山脚季平均雾日,秋(8 d)、冬(7 d)季多于春(3 d)、夏(2 d)季,而山坡表现为冬(50 d)、春(45 d)季雾日多于夏(27 d)、秋(26 d)季;平地雾在05—07时最易形成,山坡雾在04—08时最易形成,山脚雾主要在08—10时消散,山坡雾主要在09—11时消散,两者持续时间也有较大差异;夜间降温≥6℃时出现的雾日占总雾日的74.4%,气温日较差≥7.0℃时出现的雾日占总雾日的80.9%,65.2%的雾日前一日20时至当日08时平均相对湿度在90%以上,雾日多出现在风速〈3 m.s-1的条件下,83.9%的雾日近地面有逆温层存在。未饱和湿空气随气流进入喇叭口后,湿度条件发生改变,有利于在喇叭口底部区域形成雾,山区风场辐合作用有利于雾的形成与维持。
利用1991—2010年九華山不同海拔高度上的國傢氣象觀測站及區域氣象觀測站資料,分析九華山霧日時間變化特徵及其形成的氣象條件。結果錶明:近10年來,九華山山坡霧日年際變化較大,併逐年減少,山腳霧日逐年增多;山腳季平均霧日,鞦(8 d)、鼕(7 d)季多于春(3 d)、夏(2 d)季,而山坡錶現為鼕(50 d)、春(45 d)季霧日多于夏(27 d)、鞦(26 d)季;平地霧在05—07時最易形成,山坡霧在04—08時最易形成,山腳霧主要在08—10時消散,山坡霧主要在09—11時消散,兩者持續時間也有較大差異;夜間降溫≥6℃時齣現的霧日佔總霧日的74.4%,氣溫日較差≥7.0℃時齣現的霧日佔總霧日的80.9%,65.2%的霧日前一日20時至噹日08時平均相對濕度在90%以上,霧日多齣現在風速〈3 m.s-1的條件下,83.9%的霧日近地麵有逆溫層存在。未飽和濕空氣隨氣流進入喇叭口後,濕度條件髮生改變,有利于在喇叭口底部區域形成霧,山區風場輻閤作用有利于霧的形成與維持。
이용1991—2010년구화산불동해발고도상적국가기상관측참급구역기상관측참자료,분석구화산무일시간변화특정급기형성적기상조건。결과표명:근10년래,구화산산파무일년제변화교대,병축년감소,산각무일축년증다;산각계평균무일,추(8 d)、동(7 d)계다우춘(3 d)、하(2 d)계,이산파표현위동(50 d)、춘(45 d)계무일다우하(27 d)、추(26 d)계;평지무재05—07시최역형성,산파무재04—08시최역형성,산각무주요재08—10시소산,산파무주요재09—11시소산,량자지속시간야유교대차이;야간강온≥6℃시출현적무일점총무일적74.4%,기온일교차≥7.0℃시출현적무일점총무일적80.9%,65.2%적무일전일일20시지당일08시평균상대습도재90%이상,무일다출현재풍속〈3 m.s-1적조건하,83.9%적무일근지면유역온층존재。미포화습공기수기류진입나팔구후,습도조건발생개변,유리우재나팔구저부구역형성무,산구풍장복합작용유리우무적형성여유지。
The conventional observation data and the intensive observation of automatic weather station from 1991 to 2010 in different alti- tude of Jiuhua Mountain have been employed to analyze the temporal change features and meteorological conditions of fog day in the mountain area. The results show that the interannual change of fog day on the mountainside is bigger and decreases yearly but fog day on the foot of moun- tain increases yearly in the latest 10 years. The mean fog day (8 d) in autumn and mean fog day (7 d) in winter is more than the one (3 d) in spring and one (2 d) in summer on the foot of mountain, but the mean fog day (50 d) in winter and mean fog day (45 d) in spring is more than the one (27 d) in summer and one (26 d) in autumn on the mountainside. The fog occurs easily from 5 a.m.to 7 a.m. and disappears mainly from 8 a.m.to 10 a. m. on the foot of mountain, but the fog occurs easily from 4 a.m.to 8 a.m. and disappears mainly from 9 a.m.to 11 a.m. on the mountainside, and there is a difference in the fog duration between mountainside and the foot of mountain. The fog day accounts for 74.4% of the total when tem- perature in the nighttime fall more than 6 ~C ; the fog day accounts for 80.9% of the total when diurnal range of air temperature is more than 7.0 ℃. 65.2% of the total fog days have the feature that mean relative humidity is over 90% from 20 p.m. in a day to 08 a.m. on the following day. Most of fog days occur when wind speed is less than 3 m· s^-1, and 83.9% of the total fog days occur when an inversion layer exists near the ground. The change of humidity condition is favorable to originate fog in the trumpet-shaped topography areas after unsaturated wet air gets in- to the terrain; meanwhile, the convergence of wind field in the mountain area is favorable to the formation and maintenance of fog.