干旱气象
榦旱氣象
간한기상
GANSU METEOROLOGY
2014年
5期
744-750,759
,共8页
刘刈%李强%刘德%陈道劲%胡春梅
劉刈%李彊%劉德%陳道勁%鬍春梅
류예%리강%류덕%진도경%호춘매
重庆市%森林火险%盛夏%春季:火险等级
重慶市%森林火險%盛夏%春季:火險等級
중경시%삼림화험%성하%춘계:화험등급
Chongqing%forest fire danger%high summer%fire danger rating
利用重庆市34个气象站1961~2007年逐日气象观测资料以及同期NECP/NCAR逐月再分析数据,根据森林火险环境气象指数的定义,研究了重庆市森林火灾变化特征,并对春季和盛夏高森林火险等级下的典型年份的大气环流特征进行了分析。结果表明:重庆林火次数具有明显的年、季、月、日变化特征,盛夏(7~9月)和春季(2~4月)为2个高峰期,其林火次数占全年林火总数的78%,其中8月最多(占全年林火总数的18%),午后是森林火灾多发时段;春季重庆市高森林火险的大气环流特征表现为:乌拉尔山、贝加尔湖和鄂霍茨克海地区500 hPa位势高度偏低,四川盆地高度场偏高,冷空气在中高纬地区堆积,天气活动主锋区偏北;盛夏重庆市高森林火险的环流特征为:巴尔喀什湖和鄂霍茨克海地区500 hPa位势高度显著偏低,朝鲜半岛位势高度显著偏高,西太平洋副热带高压位置偏北。
利用重慶市34箇氣象站1961~2007年逐日氣象觀測資料以及同期NECP/NCAR逐月再分析數據,根據森林火險環境氣象指數的定義,研究瞭重慶市森林火災變化特徵,併對春季和盛夏高森林火險等級下的典型年份的大氣環流特徵進行瞭分析。結果錶明:重慶林火次數具有明顯的年、季、月、日變化特徵,盛夏(7~9月)和春季(2~4月)為2箇高峰期,其林火次數佔全年林火總數的78%,其中8月最多(佔全年林火總數的18%),午後是森林火災多髮時段;春季重慶市高森林火險的大氣環流特徵錶現為:烏拉爾山、貝加爾湖和鄂霍茨剋海地區500 hPa位勢高度偏低,四川盆地高度場偏高,冷空氣在中高緯地區堆積,天氣活動主鋒區偏北;盛夏重慶市高森林火險的環流特徵為:巴爾喀什湖和鄂霍茨剋海地區500 hPa位勢高度顯著偏低,朝鮮半島位勢高度顯著偏高,西太平洋副熱帶高壓位置偏北。
이용중경시34개기상참1961~2007년축일기상관측자료이급동기NECP/NCAR축월재분석수거,근거삼림화험배경기상지수적정의,연구료중경시삼림화재변화특정,병대춘계화성하고삼림화험등급하적전형년빈적대기배류특정진행료분석。결과표명:중경림화차수구유명현적년、계、월、일변화특정,성하(7~9월)화춘계(2~4월)위2개고봉기,기림화차수점전년림화총수적78%,기중8월최다(점전년림화총수적18%),오후시삼림화재다발시단;춘계중경시고삼림화험적대기배류특정표현위:오랍이산、패가이호화악곽자극해지구500 hPa위세고도편저,사천분지고도장편고,랭공기재중고위지구퇴적,천기활동주봉구편북;성하중경시고삼림화험적배류특정위:파이객십호화악곽자극해지구500 hPa위세고도현저편저,조선반도위세고도현저편고,서태평양부열대고압위치편북。
Based on the daily precipitation,maximum temperature,relative humidity and wind speed at 34 weather stations in Chongqing during 1961 -2007,the homochronous monthly reanalysis data from NECP/NCAR and forest fire data from the Headquarter of Chongqing Forest Fire Prevention during 1970-1998,the variation characteristics of forest fire was investigated by defining the me-teorological environment index of the forest fire danger.And on this basis the atmospheric circulation features of the typical years with high forest fire danger were analyzed further in spring and hot summer.The results displayed that the temporal and spatial characteris-tics of the forest fire in Chongqing was obvious.The peak periods of forest fire occurred in hot summer (from August to September)and spring (from February to April),which accounted for 78% of the annual fire.The number of forest fires was the most in August, which accounted for 18%of the annual total number.The forest fires occurred mostly at afternoon when temperature is higher.The at-mospheric circulation anomaly of the 500 hPa geopotential height field in typical years of high forest fire danger in spring was negative in Ural Mountains,Lake Baikal and Okhotsk Sea,and that was positive in Sichuan Basin.Thus the cold air was accumulated in the middle and high latitudes,which resulted in the location of the main frontal zone of weather system to northward.In hot summer,the large-scale circulation pattern of the 500 hPa geopotential height anomaly field in typical years of high forest fire danger was negative in Lake Baikal and Okhotsk region,and that was positive in Korean Peninsula which indicated location of the western Pacific subtropi-cal high was to the north.The high forest fire danger was easy to happen.