中文摘要：

为了对气象干旱时空表达方式进行探讨,提出了气象干旱时间面积函数的概念及其表达式MD（Meteorological Drought）,并利用1952年1月1日-2010年5月31日云南省全部站点逐日降水、气温观测数据计算得到的干旱CI指数,计算和分析了MD的时间分布。结果表明：（1）MD可客观、准确地表达近60年来云南发生干旱的过程和强度,解决了以往确定气象干旱事件时对持续时间和面积大小界定的主观性和不确定性,MD不仅可以完整地描述和比较有气象记录以来历史上的干旱事件,还可以连续滚动描述每个干旱过程的演变;（2）MD计算结果表明,1952-2010年云南干旱较严重的年份是：1959,1963,1966,1969,1974,1979,1984和2010年,其中,2010年为近60年来最旱的一年,干旱发生的时间比其他干旱较严重年份平均提前了90天左右,形成秋、冬、春和初夏连旱的罕见气候事件。

英文摘要：

The concept and the formula of time-area function of meteorological drought（MD） was proposed.Based on the daily precipitation and temperature data from 1 January 1951 to 31 May 2010,the CI and MD indexes are calculated and the MD temporal distribution is also analyzed.The results indicated that：（1） the MD index not only objectively but also exactly formulated the processes and intensities of meteorological drought in Yunnan Province in the last 60 years.Using the MD index the problem of subjectivity and uncertainty in defining the duration and area of meteorological drought is well solved.The MD index not only offers possibility of completely descripted and compare historical drought events since the meteorological record,but also monitors the drought development process in real time.（2） according to the MD calculating results,the more serious meteorological drought years in Yunnan Province during 1952-2010 are 1959,1963,1966,1969,1974,1979,1984 and 2010,and the most serious drought year is 2010,which took place 90 days earlier than others so that it became a rare meteorological drought event of winter-spring-early summer continuous.