Influence of Approach Channel on Wave Propagation with Varying Incident Angles

- The variation of the amplitude of waves with varying incident angles when waves propagate through a typical approach channel is discussed by a numerical calculation method, the result of which shows that the influence of the channel on wave propagation is obvious. When the wave propagation direction is in coincidence with the channel axis, the wave amplitude ratio will decrease with the increase of propagation distance. When the incident angle is 15 - 30 , there appears an area of larger wave amplitude ratio on the side slope facing the waves, but at the another side, the wave amplitude ratio is generally small, indicating that the channel has a shielding effect. When waves propagate across the channel perpendicularly, the wave amplitude ratio can be calculated with the shallow water coefficient.     

Communities structure of the planktonic halophiles in the solar saltern of Sfax,Tunisia

The composition and distribution of the main planktonic halophilic micro-organisms (heterotrophic and autotrophic picoplankton, nanoplankton, phytoplankton, ciliates) and metazooplankton were investigated in six ponds of increasing salinity in the solar salt works of Sfax, Tunisia, from January to December 2003. Marked changes in the composition and biomass of the communities were found along the salinity gradient, especially at salinities of 150 and 350. Autotrophic picoplankton, nanoplankton, diatoms, dinoflagellates and ciliates characterized the less salted ponds. Planktonic biomass was the highest at intermediate salinity as a consequence of a bloom of Ochromonas. Species richness of phytoplankton, ciliates and zooplankton greatly decrease above a salinity of 150 and typical halophiles (Dunaliella salina, cyanobacteria, Fabrea salina and Artemia salina) were found between 150 and 350 salinity. In this environment, F. salina appeared more adapted than the brine shrimp to survive during phytoplankton blooms. The halophilic plankton was however almost entirely composed of heterotrophic prokaryotes in the crystallizers. We thus observed a progressive disappearance of the autotrophic planktonic communities along the salinity gradient. Multivariate analysis of the communities provides evidence that ponds represent discrete aquatic ecosystems within this salt works.     

淡化浓海水日晒盐田原核微生物多样性分析

海滨日晒盐田具有稳定且独特的生态系统。淡化浓海水排入盐田制盐,对盐田生态系统的稳定及盐田的可持续发展具有一定的影响。本研究分析天津汉沽淡化浓海水日晒盐田不同季节不同盐度盐池原核微生物多样性现状及群落结构变化,以期为评估淡化浓海水对盐田原核微生物群落影响提供理论依据。采用温度梯度凝胶电泳和序列测定等方法,分析不同月份不同盐度盐池中细菌和古菌的多样性与群落结构变化。分别采用香农-威纳指数、加权丰富度指数和均匀度指数分析盐田微生物群落多样性、丰富度和均匀度。结果表明,淡化浓海水和溴后水中均未检测出细菌和古菌。不同月份不同盐度盐池样本中细菌多样性变化不大,优势菌主要为γ-变形菌门(γ-Proteobacteria)中的Spiribacter salinus和Pseudoalteromonassp.;古菌仅出现在盐度最高的Ⅶ号盐池中,优势古菌为广古菌门(Euryarchaeota)的Halogeometricum sp.。天津汉沽淡化浓海水日晒盐田中细菌的多样性和丰富度较低,春夏两季细菌群落结构较为稳定,秋冬季节细菌群落结构变化明显。盐度不同的盐池中细菌群落结构变化较大,随着盐度逐渐升高, Spiribacter salinus逐渐取代Pseudoalteromonas sp.成为占主要地位的优势菌种。     

青岛地区太阳紫外线辐射研究

通过对青岛地区2004年全年紫外线观测数据的分析,在预设局地纬度、海拔高度、大气中臭氧量及其分布、空气质量状况、地表反照率等因素基本不变的情况下,总结了青岛地区紫外辐射随与太阳天顶角相关的不同季节和时段、天气状况(云况)的统计性变化规律,以服务于该地区人们日常生活中对紫外线的防护,尤其是为调光生态膜的研制及改善提供参考。     

太阳能光伏发电预报方法的应用效果检验与评价

基于湖北省气象新能源研究中心光伏电站一年完整的发电数据与同期气象资料,对辐射和发电功率短期预报方法进行检验分析,结果表明:(1)太阳辐射度预报与实况有很好的对应关系,相关系数在0.77以上,均通过a=0.001的显著性水平检验。(2)光伏发电功率预报的短期方法中,以模式辐照度订正值代入光电转换模型的方法最优,预报第一天的相对均方根误差为0.16。(3)太阳辐射预报及光伏发电功率预报随太阳高度角变化而呈一定的规律性,冬季中午误差最大,夏季晚上误差最小;阴雨天气误差明显高于晴天。如何降低阴雨天气预报时的误差将是下一步工作中需要研究的重点。     

地面臭氧的变化规律和计算方法的初步研究Ⅱ.可见光波段

通过对广州鼎湖山近地面O3、NOx、太阳辐射,气象参数等项目的观测和理论分析,研究了地面O3与NOx等微量气体及太阳可见光辐射的变化规律,详细讨论了可见光波段、不同天气条件地面O3与NOx、光化学反应、气溶胶、可见光辐射等之间复杂的关系.提出以光能量传输与守恒的观点来考虑大气中与可见光辐射有关的主要过程,并以此来研究大气光化学过程中所遵循的能量规律,建立了一个简单、实用、省时的统计模式,用于计算地面O3浓度.结果表明:不同情况下,计算值与观测值吻合得均比较一致.     

Observational Study on the Downward Solar Radiation at the Sea Surface in the Western Pacific

In situ observation of downward solar radiation in the Western Pacific were carried out with voluntary merchant ships for five years from autumn 1990 through autumn 1995. Daily means of the short wave radiation were computed from the observed solar radiation. Then, the effects of shadows of the ship's superstructures on the observed radiation were corrected if needed. A 5-year average of short wave radiation along the main sea-lanes in the Western Pacific was calculated based on the observed daily mean solar radiation. Maximum values of 270–280 Wm^–2 are found around 15°–20°N in May and June, while those of 290 Wm^–2 are observed south of 18°S in November and December along the lanes. Small annual variations are found in the equatorial region. Annual mean values at the equator are about 230 Wm^–2 between New Guinea and Indonesia, and 200 Wm^–2 east of New Guinea. The 5-year average of short wave radiation was compared with the climatologies given in previous studies. We have concluded that some of results of previous studies are significantly underestimated.     

2004年厄尔尼诺事件的理论预测和实践检验

地球自转速度减慢、赤道东太平洋表层海温升高、日食-厄尔尼诺系数增大与厄尔尼诺事件发生时间在一切细节上有惊人的对应关系。这个综合检验结果给出了地球自转减速和日食-厄尔尼诺系数预测厄尔尼诺事件的有效性和准确性。2004年的弱厄尔尼诺已得到初步证实,2005年的拉尼娜有待检验。     

Improved sea-ice radiative processes in a global coupled climate model

1Introduction Seaiceplaysanimportantroleinmoderating heatandmoistureexchangesbetweentheatmosphere andtheoceanathighlatitudes.Seaicealsointeracts withthebroaderclimatesystembythepositiveice albedofeedback(Curryetal.,1995),whichamplifies projectedclimatewarmingatthehighlatitudes,andby theoceanicfeedbackinvolvingicegrowthandmelt, whichinfluencesglobalthermohalinecirculation(i.e., theNorthAtlanticDeepWaterandtheAntarcticBot- tomWater)(Walsh,1983;Barryetal.,1993). Recently,theimplementationofas…