Analysis Of Cirrus Cloud Microphysical Data

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Analysis of Cirrus Cloud Microphysical Data

Author : National Aeronautics and Space Adm Nasa
Publisher : Independently Published
ISBN 13 : 9781723942761
Total Pages : 92 pages
Book Rating : 4.9/5 (427 download)

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Book Synopsis Analysis of Cirrus Cloud Microphysical Data by : National Aeronautics and Space Adm Nasa

Download or read book Analysis of Cirrus Cloud Microphysical Data written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-09-23 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: The First International Satellite Cloud Climatology Regional Experiment (FIRE) program has the goal of improving our capabilities to understand, model and detect the properties of climatically-important clouds. This is being undertaken through a three-pronged effort of modeling, long-term observations and short-term intensive field studies. Through examination of satellite and other data it is apparent that stratus and cirrus cloud types have the greatest impact on climate due to their radiative effects and ubiquitous nature. As a result, the FIRE program has developed two paths of investigation, each having its own subset of research objectives and measurement programs. The work conducted under this grant was directed toward furthering our understanding of cirrus cloud systems. While it is known that cirrus are climatically important, the magnitude and even sign of the impact is unclear. Cirrus clouds affect the transfer of radiation according to their physical depth and location in the atmosphere and their microphysical composition. However, significant uncertainties still exist in how cirrus clouds form and how they are maintained, what their physical properties are and how they can be parameterized in numerical models. Better remote sensing techniques for monitoring cirrus cloud systems and improved modeling of radiative transfer through ice particles are also needed. A critical element in resolving these issues is a better understanding of cirrus cloud microphysical properties and how they vary. The focus of the research to be conducted under this grant was th data collected in situ by the University of North Dakota Citation aircraft. The goals of this research were to add to the body of knowledge of cirrus cloud microphysics, particularly at the small end of the size spectrum; and analyze the spatial variation of cirrus clouds.Poellot, Michael R. and Grainger, Cedric A.Langley Research CenterCIRRUS CLOUDS; REMOTE SENSING; CLOUD PHYSICS; MATHEMATICAL MODELS; IS

Analysis of Cloud Microphysical Property Retrievals in a Vertically Stratified Cirrus Cloud

Author : Erik R. Olson
Publisher :
ISBN 13 :
Total Pages : 146 pages
Book Rating : 4.:/5 (89 download)

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Book Synopsis Analysis of Cloud Microphysical Property Retrievals in a Vertically Stratified Cirrus Cloud by : Erik R. Olson

Download or read book Analysis of Cloud Microphysical Property Retrievals in a Vertically Stratified Cirrus Cloud written by Erik R. Olson and published by . This book was released on 2000 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Analysis of Cirrus Optical Properties with Data from NASA Er2 High-Resolution Interferometer Sounder (His)

Author : National Aeronautics and Space Administration (NASA)
Publisher : Createspace Independent Publishing Platform
ISBN 13 : 9781725112667
Total Pages : 28 pages
Book Rating : 4.1/5 (126 download)

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Book Synopsis Analysis of Cirrus Optical Properties with Data from NASA Er2 High-Resolution Interferometer Sounder (His) by : National Aeronautics and Space Administration (NASA)

Download or read book Analysis of Cirrus Optical Properties with Data from NASA Er2 High-Resolution Interferometer Sounder (His) written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-08-16 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 8 to 13 micron spectral region is an important atmospheric window for radiometric studies of the Earth's surface and clouds. Most of the Earth-atmosphere longwave radiative loss to space occurs in this spectral region. Selective gaseous absorption in this window occurs in the 9.6 micron ozone band with the remaining absorption dominated by the water vapor continuum. Cirrus clouds have a large impact on the transmittance of this atmospheric window region; it is therefore important to understand the interaction of cirrus cloud with the radiation field for climate studies and in the interpretation of satellite radiometric measurements. The focus was to employ observations of the High-resolution Interferometer Sounder (HIS) made during First ISCCP Regional Experiment (FIRE) to improve the understanding of the radiative properties of cirrus clouds within this window region. Studies were undertaken to investigate the coupling between the microphysical properties of cirrus clouds and their spectral variation within this window region. Extensions of the HIS studies to satellite measurements, with regards to remote sensing and interpretation, were also investigated. Smith, William L. and Ackerman, Steven A. Unspecified Center NASA-CR-186365, NAS 1.26:186365 NAG1-1015...

Parameterization of the Vertical Variability of Tropical Cirrus Cloud Microphysical and Optical Properties

Author : National Aeronautics and Space Adm Nasa
Publisher : Independently Published
ISBN 13 : 9781723746451
Total Pages : 38 pages
Book Rating : 4.7/5 (464 download)

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Book Synopsis Parameterization of the Vertical Variability of Tropical Cirrus Cloud Microphysical and Optical Properties by : National Aeronautics and Space Adm Nasa

Download or read book Parameterization of the Vertical Variability of Tropical Cirrus Cloud Microphysical and Optical Properties written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-09-16 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cloud Integrating Nephelometers (CIN) were flown on the U. North Dakota Citation aircraft and the NASA WB-57 aircraft for the purpose of measuring in-situ the optical extinction coefficient and the asymmetry parameter (g) at a wavelength of 635 nm of primarily ice particles encountered during the NASA CRYSTAL-FACE study of large cumulus clouds (Cu) and their anvils found in the southern Florida region. The probes performance was largely successful and produced archived data for vertical profiles of extinction, asymmetry parameter, and effective radius (Re), the latter being obtained by combining CIN and CVI (total water; Oregon State U.) measurements. Composites of the CIN and CVI data describing the average microphysical and optical behavior of the Cu and their anvils showed the following: The extinction increases with height as a result of the size of the particles also decreasing with height as shown by the Re measurements; near the top of anvils the size of the primary ice particles is about 10-um radius; and the value of g does not vary significantly with height and has a mean value of about 0.73 consistent with the idea that ambient ice crystals are primarily of complex shape and reflect solar radiation more efficiently than particles of pristine crystal shape. Other observations include: The g measurements were found to be an indicator of the phase of the cloud permitting identification of the clouds with water droplets, rain, and ice; visual ranges as small as several tens of meters were occasionally found in "extinction cores" that coincided with strong updraft cores; and comparison of the cloud probes on the Citation showed significant disagreement.Gerber, Hermann E.Goddard Space Flight CenterOPTICAL PROPERTIES; TROPICAL REGIONS; CLOUD PHYSICS; CIRRUS CLOUDS; PARAMETERIZATION; ANVILS; ASYMMETRY; ATTENUATION COEFFICIENTS; CORES; CRYSTALS; CUMULUS CLOUDS; NEPHELOMETERS; SOLAR RADIATION; VERTICAL AIR CURRENTS

Cirrus Particle Distribution Study

Author : Donald J. Varley
Publisher :
ISBN 13 :
Total Pages : 76 pages
Book Rating : 4.3/5 (91 download)

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Book Synopsis Cirrus Particle Distribution Study by : Donald J. Varley

Download or read book Cirrus Particle Distribution Study written by Donald J. Varley and published by . This book was released on 1978 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cirrus particle distribution data are presented for a flight that was made by the AFGL instrumented MC-130E aircraft near Denver, Colorado on 29 October 1977. The data were gathered in support of an Air Force Weapons Laboratory project. The report briefly describes some previous cirrus research and also outlines the basic cloud physics instrumentation aboard the aircraft, particularly the PMS 1-D and 2-D spectrometer equipment. Data averages are given for consecutive 30-sec periods during a 27-min flight through varying thicknesses of cirrus clouds. Besides tabular data, graphs are presented that show the temporal variations of liquid water content and particle concentration as a function of size. The 2-D data indicated most of the cirrus particles were not recognizable according to any standard classification system, although many were bullet rosettes. (Author).

Studies of Mixed-phase Cloud Microphysics Using an In-situ Unmanned Aerial Vehicle (UAV) Platform

Author : Robyn D. Williams
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (62 download)

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Book Synopsis Studies of Mixed-phase Cloud Microphysics Using an In-situ Unmanned Aerial Vehicle (UAV) Platform by : Robyn D. Williams

Download or read book Studies of Mixed-phase Cloud Microphysics Using an In-situ Unmanned Aerial Vehicle (UAV) Platform written by Robyn D. Williams and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Cirrus clouds cover between 20% - 50% of the globe and are an essential component in the climate. The improved understanding of ice cloud microphysical properties is contingent on acquiring and analyzing in-situ and remote sensing data from cirrus clouds. In-situ observations of microphysical properties of ice and mixed-phase clouds using the mini-Video Ice Particle Sizer (mini-VIPS) aboard robotic unmanned aerial vehicles (UAVs) provide a promising and powerful platform for obtaining valuable data in a cost-effective, safe, and long-term manner. The purpose of this study is to better understand cirrus microphysical properties by analyzing the effectiveness of the mini-VIPS/UAV in-situ platform. The specific goals include: (1) To validate the mini-VIPS performance by comparing the mini-VIPS data retrieved during an Artic UAV mission with data retrieved from the millimeterwavelength cloud radar (MMCR) at the Barrow ARM/CART site. (2) To analyze mini-VIPS data to survey the properties of high latitude mixedphase clouds The intercomparison between in-situ and remote sensing measurements was carried out by comparing reflectivity values calculated from in-situ measurements with observations from the MMCR facility. Good agreement between observations and measurements is obtained during the time frame where the sampled volume was saturated with respect to ice. We also have 12 shown that the degree of closure between calculated and observed reflectivity strongly correlates with the assumption of ice crystal geometry observed in the mini-VIPS images. The good correlation increases the confidence in mini-VIPS and MMCR measurements. Finally, the size distribution and ice crystal geometry obtained from the data analysis is consistent with published literature for similar conditions of temperature and ice supersaturation.

Examining Cirrus Cloud Microphysical Property Distributions and Their Relationships to the Large-scale Meteorology Using Four Years of ARM Data

Download Examining Cirrus Cloud Microphysical Property Distributions and Their Relationships to the Large-scale Meteorology Using Four Years of ARM Data PDF Online Free

Author : Erik N. Vernon
Publisher :
ISBN 13 :
Total Pages : 290 pages
Book Rating : 4.:/5 (51 download)

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Book Synopsis Examining Cirrus Cloud Microphysical Property Distributions and Their Relationships to the Large-scale Meteorology Using Four Years of ARM Data by : Erik N. Vernon

Download or read book Examining Cirrus Cloud Microphysical Property Distributions and Their Relationships to the Large-scale Meteorology Using Four Years of ARM Data written by Erik N. Vernon and published by . This book was released on 2002 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt:

The Microphysics of Ice Clouds

Author : Rosemary M. Dyer
Publisher :
ISBN 13 :
Total Pages : 44 pages
Book Rating : 4.3/5 (91 download)

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Book Synopsis The Microphysics of Ice Clouds by : Rosemary M. Dyer

Download or read book The Microphysics of Ice Clouds written by Rosemary M. Dyer and published by . This book was released on 1979 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: Published results of observations of crystal habits, particle sizes and numbers of ice particles in clouds are summarized and discussed. There are systematic variations with cloud type, and in some instances, with cloud age and location within a cloud system. However, the body of data available is insufficient to formulate a climatology of ice cloud microphysics. The several measurement techniques in current use are evaluated, as are some of the techniques now under consideration for future use. The particle enhancement observed on some occasions is discussed, and the various theories accounting for it presented. Finally, recommendations are made concerning future field programs and theoretical studies required before accurate predictions of the ice cloud microphysical environment can be made. (Author).

Mixed-Phase Clouds

Author : Constantin Andronache
Publisher : Elsevier
ISBN 13 : 012810550X
Total Pages : 302 pages
Book Rating : 4.1/5 (281 download)

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Book Synopsis Mixed-Phase Clouds by : Constantin Andronache

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

Cirrus Particle Distribution Study

Author : Donald J. Varley
Publisher :
ISBN 13 :
Total Pages : 96 pages
Book Rating : 4.3/5 ( download)

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Book Synopsis Cirrus Particle Distribution Study by : Donald J. Varley

Download or read book Cirrus Particle Distribution Study written by Donald J. Varley and published by . This book was released on 1979 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Cloud Dynamics

Author : Robert A. Houze Jr.
Publisher : Elsevier
ISBN 13 : 0080502105
Total Pages : 605 pages
Book Rating : 4.0/5 (85 download)

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Book Synopsis Cloud Dynamics by : Robert A. Houze Jr.

Download or read book Cloud Dynamics written by Robert A. Houze Jr. and published by Elsevier. This book was released on 1994-06-28 with total page 605 pages. Available in PDF, EPUB and Kindle. Book excerpt: Clouds play a critical role in the Earth's climate, general atmospheric circulation, and global water balance. Clouds are essential elements in mesoscale meteorology, atmospheric chemistry, air pollution, atmosphericradiation, and weather forecasting, and thus must be understood by any student or researcher in the atmospheric sciences.Cloud Dynamics provides a skillful and comprehensive examination of the nature of clouds--what they look like and why, how scientists observe them, and the basic dynamics and physics that underlie them. The book describes the mechanics governing each type of cloud that occurs in Earth's atmosphere, and the organization of various types of clouds in larger weather systems such as fronts, thunderstorms, and hurricanes.This book is aimed specifically at graduate students, advanced undergraduates, practicing researchers either already in atmospheric science or moving in from a related scientific field, and operational meteorologists. Some prior knowledge of atmospheric dynamics and physics is helpful, but a thorough overview of the necessary prerequisites is supplied. - Provides a complete treatment of clouds integrating the analysis of air motions with cloud structure, microphysics, and precipitation mechanics - Describes and explains the basic types of clouds and cloud systems that occur in the atmosphere-fog, stratus, stratocumulus, altocumulus, altostratus, cirrus, thunderstorms, tornadoes, waterspouts, orographically induced clouds, mesoscale convection complexes, hurricanes, fronts, and extratropical cyclones - Presents a photographic guide, presented in the first chapter, linking the examination of each type of cloud with an image to enhance visual retention and understanding - Summarizes the fundamentals, both observational and theoretical, of atmospheric dynamics, thermodynamics, cloud microphysics, and radar meteorology, allowing each type of cloud to be examined in depth - Integrates the latest field observations, numerical model simulations, and theory - Supplies a theoretical treatment suitable for the advanced undergraduate or graduate level

Characterization of 3D Cirrus Cloud and Radiation Fields Using ARS/AIRS/MODIS Data and Its Application to Climate Model

Author :
Publisher :
ISBN 13 :
Total Pages : 1 pages
Book Rating : 4.:/5 (946 download)

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Book Synopsis Characterization of 3D Cirrus Cloud and Radiation Fields Using ARS/AIRS/MODIS Data and Its Application to Climate Model by :

Download or read book Characterization of 3D Cirrus Cloud and Radiation Fields Using ARS/AIRS/MODIS Data and Its Application to Climate Model written by and published by . This book was released on 2016 with total page 1 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the report period, we have made the following research accomplishments. First, we performed analysis for a number of MODIS scenes comprising of heavy dust events and ice clouds, covering regions of frequent dust outbreaks in East Asia, Middle East, and West Africa, as well as areas associated with long-range dust transports over the Equatorial Tropical Atlantic Ocean. These scenes contain both dust/aerosols and clouds. We collected suitable aerosol/ice-cloud data, correlated ice cloud and aerosol parameters by means of statistical analysis, and interpreted resulting correlation trends based on the physical principles governing cloud microphysics. Aerosol and cloud optical depths and cloud effective particle size inferred from MODIS for selected domains were analyzed from which the parameters including dust aerosol number concentration, ice cloud water path, and ice particle number concentration were subsequently derived. We illustrated that the Twomey (solar albedo) effect can be statistically quantified based on the slope of best-fit straight lines in the correlation study. Analysis of aerosol and cloud retrieval products revealed that for all cases, the region with a larger dust aerosol optical depth is always characterized by a smaller cloud particle size, consistent with the Twomey hypothesis for aerosol-cloud interactions. Second, we developed mean correlation curves with uncertainties associated with small ice-crystal concentration observations for the mean effective ice crystal size (De) and ice water content (IWC) by dividing the atmosphere into three characteristic regions: Tropics cirrus, Midlatitude cirrus, including a temperature classification to improve correlation, and Arctic ice clouds. We illustrated that De has a high correlation with IWC based on theoretical consideration and analysis of thousands of observed ice crystal data obtained from a number of ARM-DOE field campaigns and other experiments. The correlation has the form: ln(De) = a + b ln(IWC) + c ((ln(IWC))2, where a, b, and c are fitting coefficients and are functions of three regions. We demonstrated that this correlation can be effectively incorporated in GCMs and climate models that predict IWC - a significant advance in ice microphysics parameterization for interactive cloud-radiation analysis and feedback. Substantial July mean differences are shown in the OLR (W/m2) and precipitation (mm/day) patterns between UCLA GCM simulations based on Des determined from the De-IWC correlations and the control run using a fixed ice crystal size. Third, in order to improve the computation of spectral radiative transfer processes in the WRF model, we developed a consistent and efficient radiation scheme that can better resolve the spectral bands, determine the cloud optical properties, and provide more reliable and accurate radiative heating fields. In the newly developed radiation module, we have implemented in WRF a modified and improved version referred to as the Fu-Liou-Gu scheme, which includes a combination of delta-four-stream and delta-two-stream approximations for solar and IR flux calculations, respectively. This combination has been proven to be computationally efficient and at the same time to produce a high degree of accuracy. The incorporation of nongray gaseous absorption in multiple scattering atmospheres was based on the correlated k-distribution method. The solar and IR spectra are divided into 6 and 12 bands, respectively, according to the location of absorption bands of H2O, CO2, O3, CH4, N2O, and CFCs. We further included absorption by the water vapor continuum and a number of minor absorbers in the solar spectrum leading to an additional absorption of solar flux in a clear atmosphere on the order of 1-3 W/m2. Additionally, we incorporated the ice microphysics parameterization that includes an interactive mean effective ice crystal size in association with radiation parameterizations. The Fu-Liou-Gu scheme is an ideal tool for t ...

Microphysical and Optical Properties of Cirrus and Contrails

Author : Ulrich Schumann
Publisher :
ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (832 download)

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Book Synopsis Microphysical and Optical Properties of Cirrus and Contrails by : Ulrich Schumann

Download or read book Microphysical and Optical Properties of Cirrus and Contrails written by Ulrich Schumann and published by . This book was released on 1995 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Scientific and Technical Aerospace Reports

Author :
Publisher :
ISBN 13 :
Total Pages : 538 pages
Book Rating : 4.:/5 (319 download)

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Book Synopsis Scientific and Technical Aerospace Reports by :

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 538 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.

Retrieval of Cirrus Radiative and Spatial Properties Using Independent Satellite Data Analysis Techniques

Author :
Publisher :
ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (455 download)

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Book Synopsis Retrieval of Cirrus Radiative and Spatial Properties Using Independent Satellite Data Analysis Techniques by :

Download or read book Retrieval of Cirrus Radiative and Spatial Properties Using Independent Satellite Data Analysis Techniques written by and published by . This book was released on 1992 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cirrus is one of the most poorly quantified clouds. As a part of International Satellite Cloud Climatology Project (ISCCP), intensive observations of cirrus clouds were taken in the autumn of 1986 over Wisconsin. During this First ISCCP Regional Experiment Cirrus Intensive Field Observation (FIRE Cirrus IFO), coordinated measurements from satellite, aircraft, and ground-based platforms were made of cirrus clouds. This paper deals with the verification of cirrus cloud information, both spatial and radiative, obtained for a 1986 FIRE cloud scene using measurements from two independent sensors onboard the NOAA-9 polar orbiting satellite. In addition to the wide variability in properties common for other types of clouds, cirrus clouds have the added complexity of transmissivity t values that span the entire possible domain 0 = t= 1. Thus, uncertainties exist in thin cirrus cloud amount, altitude, thickness, and optical properties as retrieved from satellite because the measured cirrus signal is affected additionally by an unknown radiation component from below.

FIRE Cirrus Science Results 1993

Author : David S. McDougal
Publisher :
ISBN 13 :
Total Pages : 232 pages
Book Rating : 4.:/5 (317 download)

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Book Synopsis FIRE Cirrus Science Results 1993 by : David S. McDougal

Download or read book FIRE Cirrus Science Results 1993 written by David S. McDougal and published by . This book was released on 1993 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt:

The Study of Cirrus Clouds Using Airborne and Satellite Data

Author : Kerry Glynne Meyer
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (74 download)

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Book Synopsis The Study of Cirrus Clouds Using Airborne and Satellite Data by : Kerry Glynne Meyer

Download or read book The Study of Cirrus Clouds Using Airborne and Satellite Data written by Kerry Glynne Meyer and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Cirrus clouds are known to play a key role in the earth's radiation budget, yet are one of the most uncertain components of the earth-atmosphere system. With the development of instruments such as the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) and the Moderate-resolution Infrared Spectroradiometer (MODIS), scientists now have an unprecedented ability to study cirrus clouds. To aid in the understanding of such clouds, a significant study of cirrus radiative properties has been undertaken. This research is composed of three parts: 1) the retrieval of tropical cirrus optical thickness using MODIS level-1b calibrated radiance data, 2) a survey of tropical cirrus cloud cover, including seasonal variations, using MODIS level-3 global daily gridded data, and 3) the simultaneous retrieval of cirrus optical thickness and ice crystal effective diameter using AVIRIS reflectance measurements.