１９９９年度，广东省杨村华侨柑桔场遭遇了两次极端恶劣的气候；第一次是１９９８／１９９９年度冬春的严重干旱，半年内降雨量仅１１７．６ｍｍ；第二次便是１９９９年“冬至”后的霜冻，１２月２１～２７日，连续霜冻１周，其中２３～２６日连续４天都是霜冻加冰冻天气，最 In 1999, the overseas Chinese citrus field in Yangcun, Guangdong Province, suffered two extremely bad weather conditions. The first was a severe drought in the winter and spring of 1998/999 with a rainfall of only 117.6 mm within six months. The second one was in 1999 “Winter solstice” after the frost, December 21 ~ 27, a week of continuous frost, of which 23 to 26 days for four consecutive days are frost plus freezing weather, the most