Radiation and Water in the Climate System:Remote Measurements——Edited by Ehrhard Raschke,Springer-Verlag Berlin Heidelberg,Germany,1996 614 pp., ISBN 3-540-61470-2

This book is the proceedings of the NATO Advanced Science Institute "Remote Sensing of Processes Governing Energy and Water Cycles in the Climate System",held in Pln,Germany 1-12 May 1995.In this book,a total of 21 conference papers are included with a special part for poster summaries.All the papers are modified or shorten versions of the original presentations and are attached with an enhanced quotation of literature fordeeper information.As the editor Dr.E.Raschke said in the Foreword."It is not perfect.and the reader may find here and there inconsistencies or even (what she/he may interpretas) an error or incompleteness.We left it entirely to the responsibility of each author toprepare the text and content according to her/his own lines.since we felt an urgent needto bring these lectures as fast as possible to the attention of the open scientific communityfor the future use."     

Radiation and Water in the Climate System:Remote Measurements——Edited by Ehrhard Raschke,Springer-Verlag Berlin Heidelberg,Germany,1996 614pp.,ISBN 3-540-61470-2

This book is the proceedings of the NATO Advanced Science Institute“RemoteSensing of Processes Governing Energy and Water Cycles in the Climate System”,held inPln,Germany 1—12 May 1995.In this book,a total of 21 conference papers are includedwith a special part for poster summaries.All the papers are modified or shorten versions     

Reply to comment by Ben-Zvi,A., D. Rosenfeld and A. Givati on the paper: Levin,Z., N. Halfon and P. Alpert, “Reassessment of rain experiments and operations in Israel including synoptic considerations,” Atmos. Res. 97, 513–525. DOI: 10.1016/j.atmosres.2010.06.011

Levin et al. (2010; hereafter LHA) (Levin, Z., Halfon, N., Alpert, P., 2010. Reassessment of rain experiments and operations in Israel including synoptic considerations. Atmos. Res. 97, 513–525. DOI:10.1016/j.atmosres.2010.06.011.), reanalyzed the results of the operational seeding in northern Israel between 1975 and 2007 and the preceding Israel 2 cloud seeding experiment (1969–1975) and concluded that there is no net increase in precipitation over the target areas. Our analysis revealed that a synoptic bias during Israel 2 is one of the reasons for the apparent positive effect of seeding in the northern target area and the negative effect in the southern area both of which disappeared in the following experiment in the south (Israel 3; 1975–1995) and the operational seeding in the north.Ben-Zvi et al. (2010;hereafter BRG) criticized our paper primarily on the ground that we did not consider the positive results of Israel 1 experiment (1960–1967). It should be noted that in Israel 1 different seeding lines were used from those in both Israel 2 and the operational period. In addition, its raw data is not accessible anymore for reanalysis. Furthermore, Israel 2 had been designed as a confirmatory cross-over experiment to Israel 1 and failed to reproduce its promising results with double ratio (DR) of ~ 1.00, namely, zero rainfall enhancements. The same DR values were also found in Israel 3 and in the operational seeding. Therefore, because of the differences in the two experiments, the lack of access to the raw data and the disappointing results of the confirmatory experiment, we decided to concentrate our analysis on the more recent seeding activities.The attempt by BRG to explain the reduction of the DR to ~ 1.00 in the operational seeding period by the suppression due to pollution have been disproved by Alpert et al., 2008, Alpert et al., 2009 and also fail to explain the sharp decline of the target/control ratio right at the beginning of the operational seeding period when the lucky draw in this area came to its end (see LHA).     

Tropical Cyclones and Polar Lows: Velocity, Size, and Energy Scales, and Relation to the 26℃ Cyclone Origin Criteria

The goal of this paper is to quantitatively formulate some necessary conditions for the development of intense atmospheric vortices. Specifically, these criteria are discussed for tropical cyclones (TC) and polar lows (PL) by using bulk formulas for fluxes of momentum, sensible heating, and latent heating between the ocean and the atmosphere. The velocity scale is used in two forms: (1) as expressed through the buoyancy flux b and the Coriolis parameter lc for rotating fluids convection, and (2) as expresse...     

苏联的МРЛ-4,МРЛ-5,МРЛ-6天气雷达

概述包括-4,-5和-6的雷达系列是苏联新的一代天气雷达,其可靠性进一步提高,并能够广泛应用数据自动处理。雷达采用集成电路,其天线由程序装置控制。平面位置/距离-高度综合指示器以及数字式直观显示器是这一系列的全新特点。用来连续检查发射机功率输出、噪声比和接收机放     

Diffuse radiation,twilight, and photochemistry — I

A photochemical scheme which includes a detailed treatment of multiple scattering up to solar zenith angles of 96° (developed for use in a GCM) has been used to study partitioning within chemical families. Attention is drawn to the different zenith angle dependence of diffuse radiation for the two spectral regions <310 nm and >310 nm. The effect that this has on the so-called 40 km ozone problem is discussed. The importance of correctly including multiple scattering for polar ozone studies is emphasised.     

Tropical cyclones and polar lows: Velocity,size, and energy scales,and relation to the 26°C cyclone origin criteria

The goal of this paper is to quantitatively formulate some necessary conditions for the development of intense atmospheric vortices. Specifically, these criteria are discussed for tropical cyclones (TC) and polar lows (PL) by using bulk formulas for fluxes of momentum, sensible heating, and latent heating between the ocean and the atmosphere. The velocity scale is used in two forms: (1) as expressed through the buoyancy flux b and the Coriolis parameter l_c for rotating fluids convection, and (2) as expressed with the cube of velocity times the drag coefficient through the formula for total kinetic energy dissipation in the atmospheric boundary layer. In the quasistationary case the dissipation equals the generation of the energy. In both cases the velocity scale can be expressed through temperature and humidity differences between the ocean and the atmosphere in terms of the reduced gravity, and both forms produce quite comparable velocity scales. Using parameters b and l_c, we can form scales of the area and, by adding the mass of a unit air column, a scale of the total kinetic energy as well. These scales nicely explain the much smaller size of a PL, as compared to a TC, and the total kinetic energy of a TC is of the order 10¹⁸-10¹⁹ J. It will be shown that wind of 33 m s^-1 is produced when the total enthalpy fluxes between the ocean and the atmosphere are about 700 W m^-2 for a TC and 1700 W m^-2 for a PL, in association with the much larger role of the latent heat in the first case and the stricter geostrophic constraints and larger static stability in the second case. This replaces the mystical role of 26^oC as a criterion for TC origin. The buoyancy flux, a product of the reduced gravity and the wind speed, together with the atmospheric static stability, determines the rate of the penetrating convection. It is known from the observations that the formation time for a PL reaching an altitude of 5--6 km can be only a few hours, and a day, or even half a day, for a TC reaching 15--18 km. These two facts allow us to construct curves on the plane of T^s and ΔT=T_s-T_a to determine possibilities for forming an intense vortex. Here, T_a is the atmospheric temperature at the height z=10 m. A PL should have ΔT>20^oC in accordance with the observations and numerical simulations. The conditions for a TC are not so straightforward but our diagram shows that the temperature difference of a few degrees, or possibly even a fraction of a degree, might be sufficient for TC development for a range of static stabilities and development times.