Latitudinal profile of UV nightglow and electron precipitations

We studied experimental data on ultra-violet (UV) nightglow in the wavelength range 300-400 nm, and energetic electron fluxes measured by low-altitude polar satellite Universitetskii-Tatiana. From statistical analysis we have found three latitudinal regions of enhanced UV emission at low, middle and high latitudes. Modeling the electron precipitations to the atmosphere gave numerical estimation of the generated UV radiation. We found that the stable and quasi-stable fluxes of electrons precipitating at middle and low latitudes are too weak to explain the observed intensities of UV radiation. The high-latitude UV nightglow with intensity of several kiloRayleighs results from particle precipitation in the regions of aurora and outer radiation belt. The low-latitude UV enhancements of several hundreds Rayleighs can be related to the emission of mesospheric atomic oxygen whose concentration increases substantially at latitudes from 20° to 40°. A mechanism of the mid-latitude UV enhancements is still unknown and requires further investigations.     

两次高原切变线诱发低涡活动的个例分析

使用NCEP/NCAR再分析格点资料,对2007年7月4～6日切变线在高原上发展,并诱发两次高原低涡造成高原中部大雨的活动过程进行了诊断分析。通过涡度收支等物理量计算,结果表明,垂直输送项和水平辐合辐散项对两次高原低涡的发展增强都起主要作用,在低涡不同发展阶段,二者贡献各有不同;在低涡二消亡阶段,水平平流项贡献增大。视热源和视水汽汇分析表明,这次降水过程以对流性降水为主,垂直运动的负值中心与视热源、视水汽汇中心对应,变化趋势基本一致,表明在降水过程大气加热是与大气上升运动密切相关,对流层中层的加热引起对流层低层抽吸作用会促进高原涡的发展,大气热源主要是降水过程的凝结潜热释放,水汽凝结起决定性作用。     

三江平原地区光合有效辐射观测研究

利用2005~2011年的太阳辐射观测资料分析三江平原地区光合有效辐射(Qp)的时间变化特征及其与总辐射(Rs)比值(Qp/Rs)的变化规律,结果表明,Qp与Rs具有相同的季节变化特征;Qp日累计值的变化范围为60.47~0.11 mol m-2 d-1,年均值为23.76 mol m-2 d-1。Qp/Rs的变化范围为1.52~2.07 mol MJ-1,年均值为1.91 mol MJ-1。Qp/Rs和Qp季节变化一致,两者都是夏季最大,春秋次之,冬季最小。通过利用2011年的Qp观测数据、大气质量数与晴空指数的相互关系,建立了适合于估量三江地区Qp的经验方程,估算值与观测值的相对误差在5.7%以内。     

Linearization of the Hamiltonian in the generalized photogravitational Chermnykh’s problem

Linearization of the Hamiltonian is being performed in the generalized photogravitational Chermnykh’s problem. The normal form of the second order part of the Hamiltonian have been found. The effect of radiation pressure, gravitational potential from the belt have been examined analytically and numerically     

数值模式中辐射参数化方案的对比试验 Ⅰ:干模式计算结果

应用一个简化的长波辐射和短波辐射参数化方案，与郭晓岚—钱永甫原有辐射参数化方案进行了对比，分析了它们对100hPa，300hPa,500hPa，700hPa及海平面气压场、高度场、温度场及辐射加热率计算结果的影响，发现，两者结果相当一致，高度场、温度场的相关系数都能达到0．9以上，短波辐射加热率的相关系数也都在0．8—0．9之间。简化方案具有计算快捷，节约机时的优点，积分模式时间720小时（5x86／133微机），所需机时约比原方案减少33％。     

我国磁层物理研究的进展和展望

在我国空间科学的开拓者赵九章教授的倡导下，1959年我国开始开展磁层物理研究工作．70年代中期以后，经过20多年的努力，我国磁层物理研究有了很大进展，现已具备重点发展和重点突破的条件本文在文献[1-3]综述的基础上，对近年来我国在磁层物理若干领域内的主要成果进行了补充评述，并对21世纪初我国磁层物理学的发展提出若干建议     

Water Quality and Phosphorus Budget of Mogan Lake,Turkey

Mogan Lake is the largest recreational area near Ankara, which is the capital city of Turkey. Increased macrophyte growth in the water body and the present levels of urban development within the catchment are reflected in declining water quality and aesthetic deterioation. A study of the water quality of the lake was undertaken to quantify the variation of phosphorus, nitrogen, and chlorophyll-a concentrations during ice-free seasons from 1992 to 1994. Its total phosphorus and chlorophyll-a concentrations indicate a meso-eutrophic status. The total phosphorus budget of Mogan Lake was measured for a period of 22 months. The estimation of nutrient loading using Dillon-Rigler nutrient budget shows that an artificial load caused too high phosphorus inputs. The management implications of phosphorus loading and budget are discussed.     

城市化对西双版纳辐射雾的影响

利用景洪气象站和大勐龙气象站的资料，对西双版纳辐射雾减少的原因进行了分析。结果表明：1960－1984年，地形地质条件相近的景洪站与大勐龙站的年雾日数、年均气温、年均湿度、年均最高气温、年均最低气温等气象要素的变化一致，可以认为两站的自然气候变化是一致的。而1985年以后，两站年雾日数和年平均湿度的变化出现较大差异。通过对人文条件的对比发现，景洪市的城市化进程远远大于大勐龙站。因此，我们初步认为城市化对西双版纳辐射雾减少所起的作用远远大于自然气候变化和森林砍伐的作用。     

改进的多角度遥感数据解译模型(英文)

利用卫星遥感数据解译地表特性需要应用辐射传输模型与反演。文中简要提到几种方法，包括蒙特卡洛光线追踪，一维物理模型，以及能够描述自然表面的整体各向异性特征的参数化公式。回顾了每种方法中所作的假设，并强调指出了处理在植被冠层这样的非均匀介质中的辐射传输问题的内在困难。在新一代改进型地球观测探测器时代的到来之际，指出进行深入研究的迫切性。     

A panel-free method for time-domain analysis of the radiation problem

A panel-free method (PFM), based on the desingularized Green’s formulae proposed by Landweber and Macagno, has been developed to solve the radiation problem of a floating body in the time domain. The velocity potential due to a non-impulsive velocity is obtained by solving the boundary integral equation in terms of source strength distribution. The singularity in the Rankine source term of the time-dependent Green function is removed. The geometry of a body surface is mathematically represented by NURBS surfaces. The integral equation can be globally discretized over the body surface by Gaussian quadratures. No assumption is needed for certain degree of approximation of distributed source strength on the body surface. The accuracy of PFM was demonstrated by its application to a classical problem of uniform flow past a sphere. The response function of a hemisphere at zero speed was then computed by PFM. The computed response function, added-mass and damping coefficients are compared with other published results.