珊瑚荧光的古降水记录

珊瑚作为热带海洋气候环境的信息载体，不仅记录了过去海洋信息，也记录了陆源环境信息。Isdale于1984年在《Nature》杂志上发表论文阐明珊瑚的黄绿荧光记录了Burdekin河的径流量变化以后，国际上对珊瑚荧光的研究逐渐发展起来，并取得了不少成果。研究表明，利用珊瑚荧光所提供的信息，可以重现过去大陆沿海的降雨变化情况、干旱或洪涝的变化旋回及入海河流的径流量变化。这对研究并重建过去气候环境、预报未来的气候变化趋势有着重要的意义。本文评述了国外对珊瑚荧光的研究进展、报道了本实验室进行了初步工作，同时，对珊瑚荧光作为环境地球化学新的代用指标所潜在的应用前景进行了讨论。     

根据树轮密度和宽度对公元1600年以来中国中北部降雨量的初步重建

根据树轮密度和宽度对公元１６００年以来中国中北部降雨量的初步重建Ｍ．Ｋ．Ｈｕｇｈｅｓ等华山松测试材料采自华山（３４°２９＇Ｎ，１１０°０５＇Ｅ，海拔２０６０ｍ），该地点的树心年代范围在４２６年以内，采样的树木接近一个建于１９５３年的气象观测站，在相同...     

A newly-discovered GPD-GEV relationship together with comparing their models of extreme precipitation in summer

It has been theoretically proven that at a high threshold an approximate expression for a quantile of GEV （Generalized Extreme Values） distribution can be derived from GPD （Generalized Pareto Distribution）. Afterwards, a quantile of extreme rainfall events in a certain return period is found using L-moment estimation and extreme rainfall events simulated by GPD and GEV, with all aspects of their results compared. Numerical simulations show that POT （Peaks Over Threshold）-based GPD is advantageous in its simple operation and subjected to practically no effect of the sample size of the primitive series, producing steady high-precision fittings in the whole field of values （including the high-end heavy tailed）. In comparison, BM （Block Maximum）-based GEV is limited, to some extent, to the probability and quantile simulation, thereby showing that GPD is an extension of GEV, the former being of greater utility and higher significance to climate research compared to the latter.     

2007年7月26日贵州省黔东南州大暴雨雨情与灾情

一、雨情 2007年7月25日20时到26日17时,贵州省黔东南州所辖10个县普降大暴雨。其中,丹寨、剑河、岑巩、施秉等4县日最大降雨均超过150.0mm,突破当地自1956年有气象记录以来的降水极值;日最大降雨量出现在丹寨县的泉山水库,达到了233.0mm（图1）。此次大暴雨天气过程的强度之大、范围之广,为当地有气象记录以来同期所罕见。     

气象因素对社会经济生活影响研究综述

从社会经济生活等角度,分析了气象要素对建筑学、流行病学、经济学以及体育学等方面的影响,并分析了降雨量与径流、泥石流、土壤侵蚀及山体滑坡的关系。     

岑溪50a气温及降水变化特征分析

利用岑溪地面气象观测站1959～2008年的气温和降水资料,对岑溪50a的气候变化做分析。结果表明:50a岑溪气温整体呈上升趋势(0.148℃/10a),特别是90年代以后增温十分明显。以80年代中期为界将岑溪50a的气候分为冷、暖两个阶段,80年代中期之前为冷期,之后为暖期。降雨量整体呈下降趋势(-15.07mm/10a),50a岑溪存在一个雨量充沛期和两个雨量偏少期,2004年以后雨量进入振荡期。     

海南遭暴雨洪涝灾害 西藏遇强降雪天气

10月,全国平均气温为10.7℃,较常年同期(9.6℃)偏高1.1℃。上海、浙江、广东、广西4省(市、区)区域平均气温为1951年以来历史同期第二高,辽宁、江苏、安徽、福建、江西、贵州为第三高。全国平均月降水量为43.4mm,较常年同期(37.0mm)偏多6.4mm;西藏区域平均降水量为1951年以来历史同期最多,海南为第三多。     

阳江地区54年来降雨量和蒸发量的变化特征

根据阳江（1953～2007年）、阳春（1961—2007年）气象观测站的降雨量和蒸发量资料,采用统计学方法分析其变化特征。发现阳江地区降雨量年际变化趋势一致,都存在大汛后数年内降雨量减少的现象。20世纪60年代以后,阳江地区蒸发量不断减少;到90年代中,达到蒸发量波谷,之后又出现上升趋势,且山区的上升趋势大于沿海地区,各季蒸发变化量与年蒸发量变化趋势相符。当年降雨量与蒸发量之差〈800mm时,阳江地区会出现大面积农作物受干旱影响的情况,每年的2月底-3月为阳江地区最缺水时期,应提前做好抗旱的准备工作。     

A Study on a Heavy Rainfall Event Triggered by an Inverted Typhoon Trough in Shandong Province

A heavy rainfall event that occurred in Shandong Province in 26 28 August 2004 was caused mainly by Typhoon Acre and cold air activities related to a westerly trough. The event was triggered by an inverted typhoon trough, which was closely associated with the intensification of the low-level southeasterly flow and the northward transport of heat and momentum in the periphery of the typhoon low. A numerical simulation of this event is performed using the nonhydrostatic mesoscale model MM5 with two-way interactive and triply-nested grids, and the structure of the inverted typhoon trough is studied. Furthermore, the formation and development mechanism of the inverted typhoon trough and a mesoscale vortex are discussed through a vorticity budget analysis. The results show that the heavy rainfall was induced by the strong convergence between the strong and weak winds within the inverted typhoon trough. Dynamic effects of the low-level jet and the diabatic heating of precipitation played an important role in the development of the inverted typhoon trough and the formation of the mesoscale vortex. The vorticity budget analysis suggests that the divergence term in the low troposphere, the horizontal advection term, and the convection term in the middle troposphere were main contributors to positive vorticity. Nonetheless, at the same pressure level, the effect of the divergence term and that of the adveetion term were opposite to each other. In the middle troposphere, the vertical transport term made a positive contribution while the tilting term made a negative contribution, and the total vorticity tendency was the net result of their counteractions. It is found that the change tendency of the relative vorticity was not uniform horizontally. A strong positive vorticity tendency occurred in the southeast of the mesoscale vortex, which is why the heavy rainfall was concentrated there. The increase of positive vorticity in the low （upper） troposphere was caused by horizontal convergence （upward transport of vorticity from the lower troposphere）. Therefore, the development of the inverted typhoon trough and the formation of the mesoscale vortex were mainly attributed to the vorticity generated in the low troposphere, and also the vertical transport of vorticity from the low and middle troposphere.