地震来临之前可能会有暗示

海上的暴风雨会给水手提供合理的警告：气压计度数下降、风向的突然转变以及天空中某些不祥的预兆都预示着暴风雨即将来临。而地震学家却没有这么幸运。数十载的监测未能提供一次即将来临的地震的任何警报信号,因此,多数地震学家都转而研究其他方面的问题。     

直面暴风雨

天气预报说,明天将有暴风雨。听到这则消息,你是会大声抱怨、责骂老天,还是会马上收拾一切、准备应对？广州前一段时间的特大暴雨恐怕让许多人都谈“雨”色变,其中难免会有人在看到“水淹七军”的惨状后大发牢骚,而这,便是一个人的人生态度的体现。既然暴风雨铁定要来了,那么与其消极逃避、怨天尤人,何不打点一切,直面暴风雨的挑战？     

逆光

天气预报说,明天将有暴风雨。心,一下就凉了。捧在手里的手机,依然在不停地振动,但我没有兴致再去看朋友们发来鼓励的短信。天气差了,跑道上再怎么用劲,都跑不快吧……就好比摄影的人选取了最美的风景,却逆光拍摄,效果将大打折扣。明天体育考试。我在跑道上,和别人相比从来没有任何的胜算,分数也总是少得可怜。何况,明天会有暴风雨的“眷顾”,湿湿的跑道只会给我更多的压力吧。随意翻看祝福的短信,本来心中还有一丝浅浅的温暖,可该死的天气预报将一切都搅乱了。     

Mesoscale Structure of Rainstorm Retrieved from Dual-Doppler Radar Observations Using the 4DVAR Assimilation Technique

The four-dimensional variational (4DVAR) data assimilation method was applied to dual-Doppler radar data about two Meiyu rainstorms observed during CHeRES (China Heavy Rain Experiment and Study). The purpose of this study is to examine the performance of the 4DVAR technique in retrieving rainstorm mesoscale structure and to reveal the feature of rainstorm mesoscale structure. Results demonstrated that the 4DVAR assimilation method was able to retrieve the detailed structure of wind, thermodynamics, and microphysics fields from dual-Doppler radar observations. The retrieved wind fields agreed with the dual-Doppler synthesized winds and were accurate. The distributions of the retrieved perturbation pressure, perturbation temperature, and microphysics fields were also reasonable through the examination of their physical consistency. Both of the two heavy rainfalls were caused by merging cloud processes. The wind shear and convergence lines at middle and lower levels were their primary dynamical characteristics. The convective system was often related to low-level convergence and upper-level divergence coupled with up-drafts. During its mature stage, the convective system was characterized by low pressure at lower level and high pressure at upper level, associated with warmer at middle level and colder at lower and upper levels than the environment. However, a region of cooling and high pressure occurred in the lower and middle levels compared to warming and low pressure in the upper level during its dissipating stage. The water vapor, cloud water, and rainwater corresponded to the convergence, the updraft and the intensive reflectivity, respectively.     

中尺度区域内暴雨落区预报的探讨

以天气学原理和预报员经验为基础，通过对影响宝鸡地区４５场暴雨天气的分析，探讨了不同尺度系统对暴雨落区的经向分布与纬向分布的影响。由此建立了暴雨落区的预报模型，对中尺度区域内暴雨落区的预报进行了有益的尝试。     

Aerosol Data Assimilation Using Data from Fengyun-3A and MODIS:Application to a Dust Storm over East Asia in 2011

Aerosol optical depth(AOD) is the most basic parameter that describes the optical properties of atmospheric aerosols,and it can be used to indicate aerosol content. In this study, we assimilated AOD data from the Fengyun-3 A(FY-3 A) and MODIS meteorological satellite using the Gridpoint Statistical Interpolation three-dimensional variational data assimilation system. Experiments were conducted for a dust storm over East Asia in April 2011. Each 0600 UTC analysis initialized a24-h Weather Research and Forecasting with Chemistry model forecast. The results generally showed that the assimilation of satellite AOD observational data can significantly improve model aerosol mass prediction skills. The AOD distribution of the analysis field was closer to the observations of the satellite after assimilation of satellite AOD data. In addition, the analysis resulting from the experiment assimilating both FY-3 A/MERSI(Medium-resolution Spectral Imager) AOD data and MODIS AOD data had closer agreement with the ground-based values than the individual assimilation of the two datasets for the dust storm over East Asia. These results suggest that the Chinese FY-3 A satellite aerosol products can be effectively applied to numerical models and dust weather analysis.     

气象预报的由来

1854年1月28日,在欧洲东南部的黑海突然出现了暴风雨。当时英国和法国正在和沙皇俄国作战,英法联合舰队停泊在黑海上。狂风巨浪把这支舰队消灭得干干净净。     

Rainfall-runoff modeling for storm events in a coastal forest catchment using neural networks

The process of transformation of rainfall into runoff over a catchment is very complex and highly nonlinear and exhibits both temporal and spatial ＂variabilities, In this article, a rainfall-runoff model using the artificial neural networks （ANN） is proposed for simulating the runoff in storm events. The study uses the data from a coastal forest catchment, located in Seto Inland Sea, Japan, This article studies the accuracy of the short-term rainfall forecast obtained by ANN time-series analysis techniques and using antecedent rainfall depths and stream flow as the input information. The verification results from the proposed model indicate that the approach of ANN rainfall-runoff model presented in this paper shows a reasonable agreement in rainfall-runoff modeling with high accuracy,     

人在南极（四）

“雪龙”号极地科考船在南大洋上遭遇一个西风带气旋的袭击，浩瀚无际的南大洋以狂风巨浪的形式迎接“雪龙”号的归来。从2008年2月14日开始，暴风雨天气已经持续了近4天时间，瞬时最大风力达九级以上，最大涌高达5米，蓝黑色的海面泛起一片片白浪，温度骤降，天空飘满雪花，狂风卷着雪花砸在窗户上发出“噼里啪啦”的声响，雪花在厚厚的玻璃上聚成一片片冰渣。