WATER AND ENERGY CYCLE IN SUBTOPICS

东亚副热带季风区夏季的能量和水循环以白玉/梅雨锋为主要特征。GAME/HUBEX的目的之一是研究中尺度云系统的演变。本研究的主要目的是阐明中尺度云系统在区域尺度能量和水循环时间变化中的作用，揭示中尺度云系统的演变及其对陆面系统时间变化的响应。继1998年之后，HUBEX组在1999年又进行了气象观测：在6月和7月（白雨季节）进行了地面通量观测和密集的气象和水文野外观测。主要观测有：15个测点的探空观测，每天4次，阜阳气象雷达观测，寿县和丰台多普勒雷达观测，密集雨量观测，AWS长期监测，通量观测。自去年以来，继续对通量进行长期监测。天气尺度的情况与上次白雨季节有很大不同。在密集的野外观测中，观测到几种降水类型。特别是6月21日至7月8日降水显著。利用JSM（日本光谱模式）、MRI-NHM和Yamasaki的模式对IOP期间在中国大陆观测到的一个云团进行了模拟研究。这些模型成功地模拟了云团，并与观测结果进行了比较。1999年11月3-9日在中国西安召开的国际会议；2000年9月12-14日在日本札幌召开的国际会议；2001年12月在中国召开的“第三届GAME-HUBEX梅雨/白球锋中尺度系统及其水循环研讨会”。在这些会议上发表了许多论文，并进行了富有成效的讨论。

The energy and water cycle in the subtropical monsoon region of the East Asia is characterized largely by Baiu/Meiyu front in summer. One of purposes of GAME/HUBEX is to study the evolution of mesoscale cloud system. Main objectives of this study are to clarify roles of a mesoscale cloud system in time variation of regional-scale energy and water cycle and to reveal evolution of a mesoscale cloud system and its response to time variation of land-surface system.Following 1998, HUBEX group also performed meteorological observation in 1999 : surface flux observations and the intensive field observation of meteorology and hydrology in June and July (Baiu season). Main observations are as follows, radiosonde observations at 15 points 4 times a day, weather-radar observations at Fuyang, Doppler radar observations at Shou-xian and Feng-tai, dense raingauge observations, AWS long term monitoring, and flux observations.The long term monitoring of flux are continued since the last year. Synoptic-scale situation was largely different from the last Baiu season. During the intensive field observation, several types of precipitation were observed. In particular, precipitation was significant during the period from 21 June to 8 July.Modeling studies have been performed about a cloud cluster observed over the China continent during the IOP using JSM (Japan Spectral Model), MRI-NHM, and Yamasaki's model. The cloud cluster was successfully simulated by these models and the results were compared with observation.HUBEX group organized international conferences and workshops : the workshop Xi'an, China on 3-9 November 1999, the international conference in Sapporo, Japan on 12-14 September 2000 and international conference entitled as"The Third GAME-HUBEX Workshop on Meso-scale Systems in Meiyu/Baiu Front and its Hydrological Cycle" in China in December 2001. Many papers were presented in there conferences and fruitful discussion was carried out.