“世界主要气候类型”教学设计

正一、导学案(一)自主学习学习活动一:运用地球"五带"图和"世界气候类型分布图"找出热带、温带、寒带的气候类型和主要受海拔高度影响形成的气候类型,并把代表气候类型的序号填入下表:(二)合作探究【学法指导】先自主学习,形成自己的想法,再小组交流,明确共识答案,标记存疑答案。学习活动二:学会阅读和分析气候直方图(气温曲线和降水量柱状图),描述气候特征。1.读景观图,分析下列四个城市"气温曲线和逐     

Heavy Rainfall Associated with a Monsoon Depression in South China: Structure Analysis

A heavy rainfall associated with the deepening of a monsoon depression happened in the summer of 2005. This process was first diagnostically analyzed and the 3D structure of the monsoon depression was discussed~ then this structure was compared with those of the monsoon depression in South Asia and the low vortex in the Meiyu front. The results showed that the heavy rainfall directly resulted from a monsoon depression in South China~ and the large-scale environment provided a favorable background for the deepening of the monsoon depression. The 3D structure of the monsoon depression was as follows. In the horizontal direction, there existed a convective cloud band to the south of the monsoon depression, which lay in a convectively instable area, with a relatively strong ascending motion in the mid and low levels of the troposphere, and the ascending motion matched well with a moist tongue, a convergence area, and a band of positive vorticity in the mid and low levels of the troposphere. In the vertical direction, the depression had an obviously cyclonic circulation in the mid and low levels of the troposphere, but no circulation from above 300 hPa. The monsoon depression corresponded to convergence and positive vorticity in the low levels, but to divergence and negative vorticity in the upper levels. The upward draft of the depression could reach the upper levels of the troposphere in the west of the depression, while the descending motion lay in the east. There was a low-level jet to the south of the depression, while the upper-level jet was not obvious. The depression was vertically warm in the upper levels and cold in the low levels, and the axis of the depression tilted southeastward with height, whose characteristics were different not only from the monsoon depression in South Asia but also from the low vortex in the Meiyu front.     

大兴安岭地区农业气象灾害的特点及防御措施

1引言 大兴安岭地区位于黑龙江省西北部,地处大兴安岭山脉东北坡和东南坡。属寒温带大陆性季风气候,全年平均气温-6℃~-1℃之间,无霜期70~110 d,平均年降水量400~550 mm,由于热量不足和季风气候的不稳定性,主要农业气象灾害有旱涝、低温冷害、霜冻、冰雹等,这些灾害严重影响     

江南“水”战 聚焦浙江“五水共治”方略——水问题频发，“五水其治”迫在眉睫!

中国是农耕国家,水利对农业有着重大的意义。我国是河湖众多的国家,所以治水在我们国家是至关重要的。但是,我国由于受季风气候的影响,降水的时空分布不均匀,各大江河流域洪涝、干旱灾害发生频繁,在三千多年有文字记载的历史中发生洪涝灾害的年度有两千两百多年。