气象科技进展
氣象科技進展
기상과기진전
Advances in Meteorological Science and Technology
2013年
3期
59-66
,共8页
降水%极值%Gamma函数%GEV分布
降水%極值%Gamma函數%GEV分佈
강수%겁치%Gamma함수%GEV분포
precipitation extreme%Gamma function%GEV distribution
利用中国气象台站1961-2006年的逐日观测降水资料,选取百分位数阈值将有效降水分为小雨、中雨、大雨和极端降水,并结合微量降水事件,采用线性回归分析和概率分布拟合的方法,研究了中国降水的时空变化特征。研究表明:1961-2006年中国年降水量在东北地区南部、黄河下游、黄土高原及长江上游这一接近直角分布的地带一致减少,且降水量减少区的范围随着降水强度的增加而缩小;黄土高原和长江上游总降水量的减少与中雨量的显著减少密切相关;长江中下游、东南地区及100°E以西地区降水量一致增加,长江中下游、东南地区总降水量的增加主要由大雨量、极端降水量的增加所造成,100°E以西地区中雨量、大雨量和极端降水量都以增加为主。除新疆西部个别台站外,年总降水频次一致表现为显著的减少趋势;年有效降水频次在西北地区显著增加,而在100°E以东地区一致减少,西部地区的增加由中雨、大雨和极端降水频次的增加共同决定,且中雨频次的贡献最大,东部地区的减少主要表现在小雨和中雨频次显著减少。微量降水事件普遍减少,冬季减少比例最大、夏季减少比例最小,北方地区的减少比例明显大于南方,这与平均气温变化幅度的季节以及空间差异都非常相似。整体而言,中国区域平均的小雨量显著减少,大雨量和极端降水量有所增加;小雨和中雨频次减少,而大雨和极端降水频次增加。
利用中國氣象檯站1961-2006年的逐日觀測降水資料,選取百分位數閾值將有效降水分為小雨、中雨、大雨和極耑降水,併結閤微量降水事件,採用線性迴歸分析和概率分佈擬閤的方法,研究瞭中國降水的時空變化特徵。研究錶明:1961-2006年中國年降水量在東北地區南部、黃河下遊、黃土高原及長江上遊這一接近直角分佈的地帶一緻減少,且降水量減少區的範圍隨著降水彊度的增加而縮小;黃土高原和長江上遊總降水量的減少與中雨量的顯著減少密切相關;長江中下遊、東南地區及100°E以西地區降水量一緻增加,長江中下遊、東南地區總降水量的增加主要由大雨量、極耑降水量的增加所造成,100°E以西地區中雨量、大雨量和極耑降水量都以增加為主。除新疆西部箇彆檯站外,年總降水頻次一緻錶現為顯著的減少趨勢;年有效降水頻次在西北地區顯著增加,而在100°E以東地區一緻減少,西部地區的增加由中雨、大雨和極耑降水頻次的增加共同決定,且中雨頻次的貢獻最大,東部地區的減少主要錶現在小雨和中雨頻次顯著減少。微量降水事件普遍減少,鼕季減少比例最大、夏季減少比例最小,北方地區的減少比例明顯大于南方,這與平均氣溫變化幅度的季節以及空間差異都非常相似。整體而言,中國區域平均的小雨量顯著減少,大雨量和極耑降水量有所增加;小雨和中雨頻次減少,而大雨和極耑降水頻次增加。
이용중국기상태참1961-2006년적축일관측강수자료,선취백분위수역치장유효강수분위소우、중우、대우화겁단강수,병결합미량강수사건,채용선성회귀분석화개솔분포의합적방법,연구료중국강수적시공변화특정。연구표명:1961-2006년중국년강수량재동북지구남부、황하하유、황토고원급장강상유저일접근직각분포적지대일치감소,차강수량감소구적범위수착강수강도적증가이축소;황토고원화장강상유총강수량적감소여중우량적현저감소밀절상관;장강중하유、동남지구급100°E이서지구강수량일치증가,장강중하유、동남지구총강수량적증가주요유대우량、겁단강수량적증가소조성,100°E이서지구중우량、대우량화겁단강수량도이증가위주。제신강서부개별태참외,년총강수빈차일치표현위현저적감소추세;년유효강수빈차재서북지구현저증가,이재100°E이동지구일치감소,서부지구적증가유중우、대우화겁단강수빈차적증가공동결정,차중우빈차적공헌최대,동부지구적감소주요표현재소우화중우빈차현저감소。미량강수사건보편감소,동계감소비례최대、하계감소비례최소,북방지구적감소비례명현대우남방,저여평균기온변화폭도적계절이급공간차이도비상상사。정체이언,중국구역평균적소우량현저감소,대우량화겁단강수량유소증가;소우화중우빈차감소,이대우화겁단강수빈차증가。
Using daily observations of precipitation for the period 1961-2006 in China, we chose the percentile based thresholds to define precipitation events with different intensities in this study. There is light rain, moderate rain, heavy rain and extreme rain. The characteristics of these effective precipitation events are analyzed in conjunction with trace rain events (<0.1mm/d). During 1961-2006, the annual precipitation decreased in southern Northeast China, the lower valley of the Yellow River, the Loess Plateau, and the upper valley of the Yangtze River, the areas with decreasing trends shrank as precipitation intensity increased, the decreasing of the total precipitation in Loess Plateau and the upper valley of the Yangtze River is closely related to significantly decreasing moderate rain;The annual precipitation generally increased in the middle and lower valleys of the Yangtze River, Southeast China and the area to the west of 100°E, which was mainly induced by the increasing heavy rain and extreme rain in the first two areas, and also by the increasing moderate rain in the third area. The annual total precipitation events generally decreased except at a few stations in Xinjiang;the annual effective precipitation events increased significantly in Northwest China while they generally decreased to the east of 100°E, the frequencies of moderate rain, heavy rain and extreme rain all increased in Northwest China with the largest increase for moderate rain events, while the decrease of light rain and moderate rain events dominated to the east of 100°E. The trace rain events generally decreased. The largest decreasing proportion occurred in winter and the lowest in summer. The decreasing proportion was obviously larger in northern China than in southern China, which is consistent with the distribution of temperature variation in China. For China as a whole, the precipitation significantly decreased for light rain while it increased for heavy rain and extreme rain;the occurrence decreased for light rain and moderate rain while it increased for heavy rain and extreme rain.