Download or read book Use of Radar Doppler Spectra in Arctic Mixed phase Cloud Studies written by Guo Yu and published by . This book was released on 2013 with total page 107 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fine scale Horizontal Structure of Arctic Mixed Phase Clouds written by M. Shupe and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent in situ observations in stratiform clouds suggest that mixed phase regimes, here defined as limited cloud volumes containing both liquid and solid water, are constrained to narrow layers (order 100 m) separating all-liquid and fully glaciated volumes (Hallett and Viddaurre, 2005). The Department of Energy Atmospheric Radiation Measurement Program's (DOE-ARM, Ackerman and Stokes, 2003) North Slope of Alaska (NSA) ARM Climate Research Facility (ACRF) recently started collecting routine measurement of radar Doppler velocity power spectra from the Millimeter Cloud Radar (MMCR). Shupe et al. (2004) showed that Doppler spectra has potential to separate the contributions to the total reflectivity of the liquid and solid water in the radar volume, and thus to investigate further Hallett and Viddaurre's findings. The Mixed-Phase Arctic Cloud Experiment (MPACE) was conducted along the NSA to investigate the properties of Arctic mixed phase clouds (Verlinde et al., 2006). We present surface based remote sensing data from MPACE to discuss the fine-scale structure of the mixed-phase clouds observed during this experiment.

Download or read book Mixed Phase Clouds written by Constantin Andronache and published by Elsevier. This book was released on 2017-09-28 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mixed-Phase Clouds: Observations and Modeling presents advanced research topics on mixed-phase clouds. As the societal impacts of extreme weather and its forecasting grow, there is a continuous need to refine atmospheric observations, techniques and numerical models. Understanding the role of clouds in the atmosphere is increasingly vital for current applications, such as prediction and prevention of aircraft icing, weather modification, and the assessment of the effects of cloud phase partition in climate models. This book provides the essential information needed to address these problems with a focus on current observations, simulations and applications. Provides in-depth knowledge and simulation of mixed-phase clouds over many regions of Earth, explaining their role in weather and climate Features current research examples and case studies, including those on advanced research methods from authors with experience in both academia and the industry Discusses the latest advances in this subject area, providing the reader with access to best practices for remote sensing and numerical modeling

Download or read book Radar Measurements and Simulations of Ice Crystal Growth in Arctic Mixed phase Clouds written by Robert Stephen Schrom and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Polarimetric radar measurements offer the potential to better understand the microphysical processes in cloud and precipitation systems. The large uncertainties in current microphysical theories and corresponding numerical models of the ice growth processes suggest a natural area where these measurements can yield large benefits. However, these uncertainties make interpretations of a given set of radar observations ambiguous. Additionally, understanding the theoretical framework behind the scattering of individual ice particles, as well as the bulk signal of a population of ice particles, is necessary to fully make use of polarimetric radar observations.Given a particular set of ice crystal physical properties, there is still uncertainty in their scattering properties. The homogeneous, reduced-density simplification for the structure of branched planar crystals is shown to produce large errors in their scattering properties. The reduced-density representations underestimatethe ZDR and KDP of individual ice crystals due to their inability to represent the distribution of mass within the particles, and the importance this distribution has on the electric-field interactions between dipoles comprising the particle.To more accurately map simple physical properties of branched planar crystals such as maximum dimension, aspect ratio, and effective density to their scattering properties, a set of electromagnetic scattering calculations for a range of realistic particle shapes were performed. The resulting scattering properties were then fit to the physical properties using polynomials; for long wavelengths (i.e., at frequencies above Ku-band), Rayleigh theory was used to determine representative scattering properties of the branched planar crystals through the use of equivalent-scattering solid-ice spheroids. These equivalent spheroids are therefore are valid at all wavelengths large relative to the maximum dimension. Using this mapping procedure, a forward model was then developed for the polarimetric radar signaturesof populations of branched planar crystals.The ambiguity in the ice crystal structure given a particular effective density leads to an inherent uncertainty in the resulting forward-simulated radar variables. This uncertainty in the forward model was accounted for by perturbing the dimensions of the equivalent-solid ice spheroids associated with a given set of physicalproperties, and using these perturbations to generate a certain number of realizations of forward-simulated radar variables. These uncertainties are largest for particles with the lowest aspect ratios and lowest effective densities, and therefore the forward model uncertainty depends on the specific distribution of ice crystal physical properties. In comparison to the spatial variability of radar observations during an Arctic mixed-phase cloud case, the forward model uncertainty is relatively low, suggesting the importance in accurately characterizing the growth environment and properly constraining the assumptions about the spectra of ice particle properties associated with the given set of radar observations. In order to better interpret radar measurements of planar crystal growth in an Arctic mixed-phase cloud, where polarimetric radar observations were collected by the ARM XSAPR in Barrow, AK, the radar forward model was coupled to a bin microphysical model of vapor depositional growth. The microphysical model is driven by a simplified 2-D kinematic model with idealized updraft and downdraft cells. Given the uncertainties in the properties of these updrafts, an ensemble of simulations with different perturbations for the updraft characteristics and the ice particle concentration was created and analyzed. In addition, a new formulation for the deposition density associated with vapor growth was implemented in the model. This new deposition density is based on the shape generation procedure for the scattering calculations and therefore more realistically captures the evolution of natural branched planar crystal structures. Given the uncertainties in these ice crystal structures, the structural quantities in the deposition density formulation were also perturbed in the ensemble.The resulting simulations were able to capture the general features of the observed radar profiles, with comparable values of ZH and ZDR . However, none of the simulations produced the observed decrease in ZDR from the top to the bottom of the profile, likely due to the differential sedimentation of hydrometeors or the lack of aggregation in the model. The simulations that fell within the variability of the observations suggested two general interpretations: one with a higher concentration of ice particles, smaller sizes, and higher densities, and another with lower concentration of ice particles, larger sizes, and lower densities. These two clusters produced KDP profiles with vastly different magnitudes; lower and higher magnitudes were observed with the low- and high-concentration clusters.Given the ubiquity of aggregation and riming in Arctic clouds, the potential for radar measurements to inform the understanding of this processes is discussed. The use of observations from multiple cases and the addition of multi-frequency observations is also likely to further improve the understanding of ice growth processes in cloud and precipitation systems.

Download or read book Springer Handbook of Atmospheric Measurements written by Thomas Foken and published by Springer Nature. This book was released on 2021-11-09 with total page 1761 pages. Available in PDF, EPUB and Kindle. Book excerpt: This practical handbook provides a clearly structured, concise and comprehensive account of the huge variety of atmospheric and related measurements relevant to meteorologists and for the purpose of weather forecasting and climate research, but also to the practitioner in the wider field of environmental physics and ecology. The Springer Handbook of Atmospheric Measurements is divided into six parts: The first part offers instructive descriptions of the basics of atmospheric measurements and the multitude of their influencing factors, fundamentals of quality control and standardization, as well as equations and tables of atmospheric, water, and soil quantities. The subsequent parts present classical in-situ measurements as well as remote sensing techniques from both ground-based as well as airborn or satellite-based methods. The next part focusses on complex measurements and methods that integrate different techniques to establish more holistic data. Brief discussions of measurements in soils and water, at plants, in urban and rural environments and for renewable energies demonstrate the potential of such applications. The final part provides an overview of atmospheric and ecological networks. Written by distinguished experts from academia and industry, each of the 64 chapters provides in-depth discussions of the available devices with their specifications, aspects of quality control, maintenance as well as their potential for the future. A large number of thoroughly compiled tables of physical quantities, sensors and system characteristics make this handbook a unique, universal and useful reference for the practitioner and absolutely essential for researchers, students, and technicians.

Download or read book Polarimetric Doppler Weather Radar written by V. N. Bringi and published by Cambridge University Press. This book was released on 2001-08-30 with total page 666 pages. Available in PDF, EPUB and Kindle. Book excerpt: This 2001 book provides a detailed introduction to the principles of Doppler and polarimetric radar, focusing in particular on their use in the analysis of weather systems. The design features and operation of practical radar systems are highlighted throughout the book in order to illustrate important theoretical foundations. The authors begin by discussing background topics such as electromagnetic scattering, polarization, and wave propagation. They then deal in detail with the engineering aspects of pulsed Doppler polarimetric radar, including the relevant signal theory, spectral estimation techniques, and noise considerations. They close by examining a range of key applications in meteorology and remote sensing. The book will be of great use to graduate students of electrical engineering and atmospheric science as well as to practitioners involved in the applications of polarimetric radar systems.

Download or read book Fast Processes in Large Scale Atmospheric Models written by Yangang Liu and published by John Wiley & Sons. This book was released on 2023-12-11 with total page 483 pages. Available in PDF, EPUB and Kindle. Book excerpt: Improving weather and climate prediction with better representation of fast processes in atmospheric models Many atmospheric processes that influence Earth’s weather and climate occur at spatiotemporal scales that are too small to be resolved in large scale models. They must be parameterized, which means approximately representing them by variables that can be resolved by model grids. Fast Processes in Large-Scale Atmospheric Models: Progress, Challenges and Opportunities explores ways to better investigate and represent multiple parameterized processes in models and thus improve their ability to make accurate climate and weather predictions. Volume highlights include: Historical development of the parameterization of fast processes in numerical models Different types of major sub-grid processes and their parameterizations Efforts to unify the treatment of individual processes and their interactions Top-down versus bottom-up approaches across multiple scales Measurement techniques, observational studies, and frameworks for model evaluation Emerging challenges, new opportunities, and future research directions The American Geophysical Union promotes discovery in Earth and space science for the benefit of humanity. Its publications disseminate scientific knowledge and provide resources for researchers, students, and professionals.

Download or read book The Use of Radar for Studies of Clouds written by Earl E. Gossard and published by . This book was released on 1978 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Clouds and Their Climatic Impact written by Sylvia Sullivan and published by John Wiley & Sons. This book was released on 2023-12-19 with total page 371 pages. Available in PDF, EPUB and Kindle. Book excerpt: Clouds and Their Climatic Impacts Clouds are an influential and complex element of Earth’s climate system. They evolve rapidly in time and exist over small spatial scales, but also affect global radiative balance and large-scale circulations. With more powerful models and extensive observations now at our disposal, the climate impact of clouds is receiving ever more research attention. Clouds and Their Climatic Impacts: Radiation, Circulation, and Precipitation presents an overview of our current understanding on various types of clouds and cloud systems and their multifaceted role in the radiative budget, circulation patterns, and rainfall. Volume highlights include: Interactions of aerosol with both liquid and ice clouds Surface and atmospheric cloud radiative feedbacks and effects Arctic, extratropical, and tropical clouds Cloud-circulation coupling at global, meso, and micro scales Precipitation efficiency, phase, and measurements The role of machine learning in understanding clouds and climate The American Geophysical Union promotes discovery in Earth and space science for the benefit of humanity. Its publications disseminate scientific knowledge and provide resources for researchers, students, and professionals.

Download or read book Issues in Earth Sciences Geology and Geophysics 2011 Edition written by and published by ScholarlyEditions. This book was released on 2012-01-09 with total page 6804 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues in Earth Sciences, Geology, and Geophysics: 2011 Edition is a ScholarlyEditions™ eBook that delivers timely, authoritative, and comprehensive information about Earth Sciences, Geology, and Geophysics. The editors have built Issues in Earth Sciences, Geology, and Geophysics: 2011 Edition on the vast information databases of ScholarlyNews.™ You can expect the information about Earth Sciences, Geology, and Geophysics in this eBook to be deeper than what you can access anywhere else, as well as consistently reliable, authoritative, informed, and relevant. The content of Issues in Earth Sciences, Geology, and Geophysics: 2011 Edition has been produced by the world’s leading scientists, engineers, analysts, research institutions, and companies. All of the content is from peer-reviewed sources, and all of it is written, assembled, and edited by the editors at ScholarlyEditions™ and available exclusively from us. You now have a source you can cite with authority, confidence, and credibility. More information is available at http://www.ScholarlyEditions.com/.

Download or read book Journal of Atmospheric and Oceanic Technology written by and published by . This book was released on 2004 with total page 1010 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Internal Refractive Index Spectra of Clouds from Forward Scatter Radar Observations written by Earl E. Gossard and published by . This book was released on 1979 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Observation and Modeling Study of Arctic Multilayered Mixed phase Boundary Layer Clouds written by Hui Lai and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: To better understand the dynamic and thermodynamic processes that form and maintain Arctic multilayered mixed-phase clouds, Moderate Resolution Imaging Spectroradiometer (MODIS) radiances, High Spectral Resolution Lidar (HSRL) backscatter, and Ka-band ARM zenith radar (KAZR) returns along with balloon-borne sounding thermodynamic profiles, were analyzed from 1-3 May 2013. The observations, together with ERA-Interim Reanalysis data, indicate that three cloud regimes were present during this period. Frontal clouds occurred in a north to south band with Barrow located on their eastern edge at 00:00 UTC 2 May. By mid-day the frontal clouds had moved into the Barrow region. A broad low-altitude stratus deck existed to the west and north of Barrow, advecting into the Barrow region by the end of 2 May as the frontal clouds cleared the region. The stratus deck remained over Barrow throughout 3 May and several days beyond it. Boundary layer cellular convection was the predominant cloud type in the vicinity of the low pressure to the east and north of Barrow on 1-2 May.On 2 May 2013 shallow single- and multi-layered, mixed-phase clouds observed by the HSRL and KAZR were present above Barrow, Alaska, leading at various times to pristine crystals, rimed crystals and aggregates of crystals at the surface. During this case study period, a weak surface trough was located to the north and east of Barrow with a high pressure ridge to its west. The associated surface front was located over Barrow and extended to the north over the Arctic Ocean. High spatial (250-m) pixel resolution MODIS radiances show low level cloud streets in the vicinity of Barrow and just to its east oriented perpendicular to the mean wind around 00:00 UTC 2 May. Low altitude cloud streets also existed to the west of Barrow at this time, though oriented parallel to the mean wind. Finally, additional cloud streets to the southwest of Barrow and perpendicular to the mean wind also were present but in the higher altitude frontal clouds. The low altitude cloud streets just to the east and west of Barrow, and under the frontal cloud layer, were the source of the multilayered clouds on this day; this study focused on the ones to the west. These cloud streets formed in an environment of strong vertical wind shear with an underlying shallow buoyant layer near the surface.The Weather and Research Forecasting (WRF) model was used to conduct mesoscale simulations for this day and the two surrounding ones. For the three-day period from 1-3 May 2013 the 27-km spatial grid spacing WRF model reproduced mesoscale geopotential height, wind, relative humidity and sea-level pressure fields similar to those contained in the (0.75 lat/lon) ERA-Interim Reanalysis. Moreover, the model was able to reproduce the three cloud systems evident in the observations: the low cloud-liquid stratus to the west of Barrow, the deep frontal cloud layer in the vicinity of Barrow, and the more convective cloud cells with heights in-between to the east of Barrow.In the WRF modeling approach six nested domains were used with horizontal grid spacings starting from 27 km and scaling down in ratios of 3 to 1, with the finest domain run in large eddy simulation mode at 111-m horizontal grid spacing in an attempt to capture the short (~ 1.5-km) wavelength of the cloud streets apparent in the satellite data. Model results show that warm air advection and surface radiative heating created enhanced near surface instability, providing the buoyancy necessary to drive the initial convection. These buoyant parcels entered the region of strong vertical shear, leading to Richardson numbers around 0.2 and the conditions favorable for the formation of roll clouds. The wavelengths of the roll clouds produced by the inner four nested domains varied from 33 km for the outermost 3-km domain to 1 km for the finest 0.111-km grid spacing domain. The finest grid spacing domain roll-cloud wavelengths were comparable to those observed by MODIS, illustrating the necessity of using a grid spacing sufficiently small to place at least 7 to 10 grid points across a roll in order to resolve it.

Download or read book Cloud Dynamics written by Robert A. Houze Jr. and published by Academic Press. This book was released on 2014-07-08 with total page 457 pages. Available in PDF, EPUB and Kindle. Book excerpt: As models of the Earth/atmosphere system and observations become ever more sophisticated, and concerns about climate change and societal impacts of extreme weather and its forecasting grow, understanding the role of clouds in the atmosphere is increasingly vital. Cloud Dynamics, Second Edition provides the essential information needed to understand how clouds affect climate and weather. This comprehensive book examines the underlying physics and dynamics of every specific type of cloud that occurs in the Earth's atmosphere, showing how clouds differ dynamically depending on whether they occur over oceans or mountains, or as parts of atmospheric storms, such as thunderstorms, tropical cyclones, or warm and cold fronts. Covering both the microphysical and macrophysical aspects of clouds, the book treats all of the physical scales involved in cloud processes, from the microscale of the individual drops and ice particles up to scales of storms in which the clouds occur. As observational technology advances with increasingly sophisticated remote sensing capabilities, detailed understanding of how the dynamics and physics of clouds affect the quantities being measured is of paramount importance. This book underpins the work necessary for proper interpretation of these observations, now and in the future. Provides the holistic understanding of clouds needed to pursue research on topics vital to life on Earth Provides in-depth understanding of all types of clouds over all regions of Earth, from the poles to the equator Includes detailed physical and dynamical insight into the entire spectrum of clouds populating Earth's atmosphere

Download or read book Physics and Chemistry of Clouds written by Dennis Lamb and published by Cambridge University Press. This book was released on 2011-04-28 with total page 599 pages. Available in PDF, EPUB and Kindle. Book excerpt: Clouds affect our daily weather and play key roles in the global climate. Through their ability to precipitate, clouds provide virtually all of the fresh water on Earth and are a crucial link in the hydrologic cycle. With ever-increasing importance being placed on quantifiable predictions - from forecasting the local weather to anticipating climate change - we must understand how clouds operate in the real atmosphere, where interactions with natural and anthropogenic pollutants are common. This textbook provides students - whether seasoned or new to the atmospheric sciences - with a quantitative yet approachable path to learning the inner workings of clouds. Developed over many years of the authors' teaching at Pennsylvania State University, Physics and Chemistry of Clouds is an invaluable textbook for advanced students in atmospheric science, meteorology, environmental sciences/engineering and atmospheric chemistry. It is also a very useful reference text for researchers and professionals.

Download or read book Thermodynamics Kinetics and Microphysics of Clouds written by Vitaly I. Khvorostyanov and published by Cambridge University Press. This book was released on 2014-08-25 with total page 801 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thermodynamics, Kinetics, and Microphysics of Clouds presents a unified theoretical foundation that provides the basis for incorporating cloud microphysical processes in cloud and climate models. In particular, the book provides: • A theoretical basis for understanding the processes of cloud particle formation, evolution and precipitation, with emphasis on spectral cloud microphysics based on numerical and analytical solutions of the kinetic equations for the drop and crystal size spectra along with the supersaturation equation • The latest detailed theories and parameterizations of drop and crystal nucleation suitable for cloud and climate models derived from the general principles of thermodynamics and kinetics • A platform for advanced parameterization of clouds in weather prediction and climate models • The scientific foundation for weather and climate modification by cloud seeding. This book will be invaluable for researchers and advanced students engaged in cloud and aerosol physics, and air pollution and climate research.

Download or read book Advances in Numerical Model Data Assimilation and Observations for Hazardous Weather Prediction written by Feifei Shen and published by Frontiers Media SA. This book was released on 2023-10-30 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: Accurate and timely forecasting of hazardous weather events induced by meso-scale convection systems (MCSs) is the key to safeguarding lives and property. Yet the MCS forecasting is challenging due to imperfect initial numerical conditions that lack meso-scale convective information and multi-scale dynamic and thermodynamic consistency. Remote sensing observations are the primary source of estimating weather conditions, such as moisture, wind velocity, and precipitation. It is of fundamental pivotality to develop data assimilation technologies to enhance applications of multi-source observations. Performance assessments of new types of observations facilitate the network designment for regional- and storm-scale numerical models. This Research Topic seeks submissions underscoring the improvement of the accuracy of MCS predictions, warnings, and decision support for high-impact weather events as well as observation network designs.