23 results on '"Yost, Christopher R."'
Search Results
2. VIIRS Edition 1 Cloud Properties for CERES, Part 1: Algorithm Adjustments and Results
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Minnis, Patrick, primary, Sun-Mack, Sunny, additional, Smith, William L., additional, Trepte, Qing Z., additional, Hong, Gang, additional, Chen, Yan, additional, Yost, Christopher R., additional, Chang, Fu-Lung, additional, Smith, Rita A., additional, Heck, Patrick W., additional, and Yang, Ping, additional
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- 2023
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3. Global Clear-Sky Surface Skin Temperature from Multiple Satellites Using a Single-Channel Algorithm with Angular Anisotropy Corrections
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Scarino, Benjamin R, Minnis, Patrick, Chee, Thad, Bedka, Kristopher M, Yost, Christopher R, and Palikonda, Rabindra
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Earth Resources And Remote Sensing - Abstract
Surface skin temperature (T(sub s)) is an important parameter for characterizing the energy exchange at the ground/water-atmosphere interface. The Satellite ClOud and Radiation Property retrieval System (SatCORPS) employs a single-channel thermal-infrared (TIR) method to retrieve T(sub s) over clear-sky land and ocean surfaces from data taken by geostationary Earth orbit (GEO) and low Earth orbit (LEO) satellite imagers. GEO satellites can provide somewhat continuous estimates of T(sub s) over the diurnal cycle in non-polar regions, while polar T(sub s) retrievals from LEO imagers, such as the Advanced Very High Resolution Radiometer (AVHRR), can complement the GEO measurements. The combined global coverage of remotely sensed T(sub s), along with accompanying cloud and surface radiation parameters, produced in near-realtime and from historical satellite data, should be beneficial for both weather and climate applications. For example, near-realtime hourly T(sub s) observations can be assimilated in high-temporal-resolution numerical weather prediction models and historical observations can be used for validation or assimilation of climate models. Key drawbacks to the utility of TIR-derived T(sub s) data include the limitation to clear-sky conditions, the reliance on a particular set of analyses/reanalyses necessary for atmospheric corrections, and the dependence on viewing and illumination angles. Therefore, T(sub s) validation with established references is essential, as is proper evaluation of T(sub s) sensitivity to atmospheric correction source. This article presents improvements on the NASA Langley GEO satellite and AVHRR TIR-based T(sub s) product that is derived using a single-channel technique. The resulting clear-sky skin temperature values are validated with surface references and independent satellite products. Furthermore, an empirically adjusted theoretical model of satellite land surface temperature (LST) angular anisotropy is tested to improve satellite LST retrievals. Application of the anisotropic correction yields reduced mean bias and improved precision of GOES-13 LST relative to independent Moderate-resolution Imaging Spectroradiometer (MYD11_L2) LST and Atmospheric Radiation Measurement Program ground station measurements. It also significantly reduces inter-satellite differences between LSTs retrieved simultaneously from two different imagers. The implementation of these universal corrections into the SatCORPS product can yield significant improvement in near-global-scale, near-realtime, satellite-based LST measurements. The immediate availability and broad coverage of these skin temperature observations should prove valuable to modelers and climate researchers looking for improved forecasts and better understanding of the global climate model.
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- 2017
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4. Influence of Cloud-Top Height and Geometric Thickness on a MODIS Infrared-Based Ice Cloud Retrieval
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Garrett, Kevin J., Yang, Ping, Nasiri, Shaima L., Yost, Christopher R., and Baum, Bryan A.
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- 2009
5. Validation of Cloud Properties From Multiple Satellites Using CALIOP Data
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Yost, Christopher R, Minnis, Patrick, Bedka, Kristopher M, Heck, Patrick W, Palikonda, Rabindra, Sun-Mack, Sunny, and Trepte, Qing
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Meteorology And Climatology - Abstract
The NASA Langley Satellite ClOud and Radiative Property retrieval System (SatCORPS) is routinely applied to multispectral imagery from several geostationary and polar-orbiting imagers to retrieve cloud properties for weather and climate applications. Validation of the retrievals with independent datasets is continuously ongoing in order to understand differences caused by calibration, spatial resolution, viewing geometry, and other factors. The CALIOP instrument provides a decade of detailed cloud observations which can be used to evaluate passive imager retrievals of cloud boundaries, thermodynamic phase, cloud optical depth, and water path on a global scale. This paper focuses on comparisons of CALIOP retrievals to retrievals from MODIS, VIIRS, AVHRR, GOES, SEVIRI, and MTSAT. CALIOP is particularly skilled at detecting weakly-scattering cirrus clouds with optical depths less than approx. 0.5. These clouds are often undetected by passive imagers and the effect this has on the property retrievals is discussed.
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- 2016
6. Long Term Cloud Property Datasets From MODIS and AVHRR Using the CERES Cloud Algorithm
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Minnis, Patrick, Bedka, Kristopher M, Doelling, David R, Sun-Mack, Sunny, Yost, Christopher R, Trepte, Qing Z, Bedka, Sarah T, Palikonda, Rabindra, Scarino, Benjamin R, Chen, Yan, Hong, Gang, and Bhatt, Rajendra
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Meteorology And Climatology - Abstract
Cloud properties play a critical role in climate change. Monitoring cloud properties over long time periods is needed to detect changes and to validate and constrain models. The Clouds and the Earth's Radiant Energy System (CERES) project has developed several cloud datasets from Aqua and Terra MODIS data to better interpret broadband radiation measurements and improve understanding of the role of clouds in the radiation budget. The algorithms applied to MODIS data have been adapted to utilize various combinations of channels on the Advanced Very High Resolution Radiometer (AVHRR) on the long-term time series of NOAA and MetOp satellites to provide a new cloud climate data record. These datasets can be useful for a variety of studies. This paper presents results of the MODIS and AVHRR analyses covering the period from 1980-2014. Validation and comparisons with other datasets are also given.
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- 2015
7. CERES MODIS Cloud Product Retrievals for Edition 4—Part II: Comparisons to CloudSat and CALIPSO
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Yost, Christopher R., primary, Minnis, Patrick, additional, Sun-Mack, Sunny, additional, Chen, Yan, additional, and Smith, William L., additional
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- 2021
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8. CERES MODIS Cloud Product Retrievals for Edition 4—Part I: Algorithm Changes
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Minnis, Patrick, primary, Sun-Mack, Szedung, additional, Chen, Yan, additional, Chang, Fu-Lung, additional, Yost, Christopher R., additional, Smith, William L., additional, Heck, Patrick W., additional, Arduini, Robert F., additional, Bedka, Sarah T., additional, Yi, Yuhong, additional, Hong, Gang, additional, Jin, Zhonghai, additional, Painemal, David, additional, Palikonda, Rabindra, additional, Scarino, Benjamin R., additional, Spangenberg, Douglas A., additional, Smith, Rita A., additional, Trepte, Qing Z., additional, Yang, Ping, additional, and Xie, Yu, additional
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- 2021
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9. Applications for Near-Real Time Satellite Cloud and Radiation Products
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Minnis, Patrick, Palikonda, Rabindra, Chee, Thad L, Bedka, Kristopher M, Smith, W, Ayers, Jeffrey K, Benjamin, Stanley, Chang, F.-L, Nguyen, Louis, Norris, Peter, Rolf, Riechle, Reinecker, Michele, Shan, B, DaSilva, Arlindo, and Yost, Christopher R
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Meteorology And Climatology - Abstract
At NASA Langley Research Center, a variety of cloud, clear-sky, and radiation products are being derived at different scales from regional to global using geostationary satellite (GEOSat) and lower Earth-orbiting (LEOSat) imager data. With growing availability, these products are becoming increasingly valuable for weather forecasting and nowcasting. These products include, but are not limited to, cloud-top and base heights, cloud water path and particle size, cloud temperature and phase, surface skin temperature and albedo, and top-of-atmosphere radiation budget. Some of these data products are currently assimilated operationally in a numerical weather prediction model. Others are used unofficially for nowcasting, while testing is underway for other applications. These applications include the use of cloud water path in an NWP model, cloud optical depth for detecting convective initiation in cirrus-filled skies, and aircraft icing condition diagnoses among others. This paper briefly describes a currently operating system that analyzes data from GEOSats around the globe (GOES, Meteosat, MTSAT, FY-2) and LEOSats (AVHRR and MODIS) and makes the products available in near-real time through a variety of media. Current potential future use of these products is discussed.
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- 2012
10. Using Information From Prior Satellite Scans to Improve Cloud Detection Near the Day-Night Terminator
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Yost, Christopher R, Minnis, Patrick, Trepte, Qing Z, Palikonda, Rabindra, Ayers, Jeffrey K, and Spangenberg, Doulas A
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Meteorology And Climatology - Abstract
With geostationary satellite data it is possible to have a continuous record of diurnal cycles of cloud properties for a large portion of the globe. Daytime cloud property retrieval algorithms are typically superior to nighttime algorithms because daytime methods utilize measurements of reflected solar radiation. However, reflected solar radiation is difficult to accurately model for high solar zenith angles where the amount of incident radiation is small. Clear and cloudy scenes can exhibit very small differences in reflected radiation and threshold-based cloud detection methods have more difficulty setting the proper thresholds for accurate cloud detection. Because top-of-atmosphere radiances are typically more accurately modeled outside the terminator region, information from previous scans can help guide cloud detection near the terminator. This paper presents an algorithm that uses cloud fraction and clear and cloudy infrared brightness temperatures from previous satellite scan times to improve the performance of a threshold-based cloud mask near the terminator. Comparisons of daytime, nighttime, and terminator cloud fraction derived from Geostationary Operational Environmental Satellite (GOES) radiance measurements show that the algorithm greatly reduces the number of false cloud detections and smoothes the transition from the daytime to the nighttime clod detection algorithm. Comparisons with the Geoscience Laser Altimeter System (GLAS) data show that using this algorithm decreases the number of false detections by approximately 20 percentage points.
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- 2012
11. Simulations of Infrared Radiances Over a Deep Convective Cloud System Observed During TC4- Potential for Enhancing Nocturnal Ice Cloud Retrievals
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Minnis, Patrick, Hong, Gang, Ayers, Jeffrey Kirk, Smith, William L, Yost, Christopher R, Heymsfield, Andrew J, Heymsfield, Gerald M, Hlavka, Dennis L, King, Michael D, Korn, Errol M, Mcgill, Matthew J, Selkirk, Henry B, Thompson, Anne M, Tian, Lin, and Yang, Ping
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Meteorology And Climatology - Abstract
Retrievals of ice cloud properties using infrared measurements at 3.7, 6.7, 7.3, 8.5, 10.8, and 12.0 microns can provide consistent results regardless of solar illumination, but are limited to cloud optical thicknesses tau < approx.6. This paper investigates the variations in radiances at these wavelengths over a deep convective cloud system for their potential to extend retrievals of tau and ice particle size D(sub e) to optically thick clouds. Measurements from the Moderate Resolution Imaging Spectroradiometer Airborne Simulator--ASTER, the Scanning High-resolution Interferometer Sounder, the Cloud Physics Lidar (CPL), and the Cloud Radar System (CRS) aboard the NASA ER-2 aircraft during the NASA TC4 (Tropical Composition, Cloud and Climate Coupling) experiment flight during 5 August 2007, are used to examine the retrieval capabilities of infrared radiances over optically thick ice clouds. Simulations based on coincident in-situ measurements and combined cloud tau from CRS and CPL measurements are comparable to the observations. They reveal that brightness temperatures at these bands and their differences (BTD) are sensitive to tau up to approx.20 and that for ice clouds having tau > 20, the 3.7 - 10.8 microns and 3.7 - 6.7 microns BTDs are the most sensitive to D(sub e). Satellite imagery appears consistent with these results. Keywords: clouds; optical depth; particle size; satellite; TC4; multispectral thermal infrared
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- 2012
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12. Global Cloud Detection for CERES Edition 4 Using Terra and Aqua MODIS Data
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Trepte, Qing Z., primary, Bedka, Kristopher M., additional, Chee, Thad L., additional, Minnis, Patrick, additional, Sun-Mack, Szedung, additional, Yost, Christopher R., additional, Chen, Yan, additional, Jin, Zhonghai, additional, Hong, Gang, additional, Chang, Fu-Lung, additional, and Smith, William L., additional
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- 2019
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13. Evaluation of Satellite-Based Upper Troposphere Cloud Top Height Retrievals in Multilayer Cloud Conditions During TC4
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Chang, Fu-Lung, Minnis, Patrick, Ayers, J. Kirk, McGill, Matthew J, Palikonda, Rabindra, Spangenberg, Douglas A, Smith, William L., Jr, and Yost, Christopher R
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Meteorology And Climatology - Abstract
Upper troposphere cloud top heights (CTHs), restricted to cloud top pressures (CTPs) less than 500 hPa, inferred using four satellite retrieval methods applied to Twelfth Geostationary Operational Environmental Satellite (GOES-12) data are evaluated using measurements during the July August 2007 Tropical Composition, Cloud and Climate Coupling Experiment (TC4). The four methods are the single-layer CO2-absorption technique (SCO2AT), a modified CO2-absorption technique (MCO2AT) developed for improving both single-layered and multilayered cloud retrievals, a standard version of the Visible Infrared Solar-infrared Split-window Technique (old VISST), and a new version of VISST (new VISST) recently developed to improve cloud property retrievals. They are evaluated by comparing with ER-2 aircraft-based Cloud Physics Lidar (CPL) data taken during 9 days having extensive upper troposphere cirrus, anvil, and convective clouds. Compared to the 89% coverage by upper tropospheric clouds detected by the CPL, the SCO2AT, MCO2AT, old VISST, and new VISST retrieved CTPs less than 500 hPa in 76, 76, 69, and 74% of the matched pixels, respectively. Most of the differences are due to subvisible and optically thin cirrus clouds occurring near the tropopause that were detected only by the CPL. The mean upper tropospheric CTHs for the 9 days are 14.2 (+/- 2.1) km from the CPL and 10.7 (+/- 2.1), 12.1 (+/- 1.6), 9.7 (+/- 2.9), and 11.4 (+/- 2.8) km from the SCO2AT, MCO2AT, old VISST, and new VISST, respectively. Compared to the CPL, the MCO2AT CTHs had the smallest mean biases for semitransparent high clouds in both single-layered and multilayered situations whereas the new VISST CTHs had the smallest mean biases when upper clouds were opaque and optically thick. The biases for all techniques increased with increasing numbers of cloud layers. The transparency of the upper layer clouds tends to increase with the numbers of cloud layers.
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- 2010
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14. A prototype method for diagnosing high ice water content probability using satellite imager data
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Yost, Christopher R., primary, Bedka, Kristopher M., additional, Minnis, Patrick, additional, Nguyen, Louis, additional, Strapp, J. Walter, additional, Palikonda, Rabindra, additional, Khlopenkov, Konstantin, additional, Spangenberg, Douglas, additional, Smith Jr., William L., additional, Protat, Alain, additional, and Delanoe, Julien, additional
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- 2018
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15. A Prototype Method for Diagnosing High Ice Water Content Probability Using Satellite Imager Data
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Yost, Christopher R., primary, Bedka, Kristopher M., additional, Minnis, Patrick, additional, Nguyen, Louis, additional, Strapp, J. Walter, additional, Palikonda, Rabindra, additional, Khlopenkov, Konstantin, additional, Spangenberg, Douglas, additional, Smith Jr., William L., additional, Protat, Alain, additional, and Delanoe, Julien, additional
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- 2017
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16. Supplementary material to "A Prototype Method for Diagnosing High Ice Water Content Probability Using Satellite Imager Data"
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Yost, Christopher R., primary, Bedka, Kristopher M., additional, Minnis, Patrick, additional, Nguyen, Louis, additional, Strapp, J. Walter, additional, Palikonda, Rabindra, additional, Khlopenkov, Konstantin, additional, Spangenberg, Douglas, additional, Smith Jr., William L., additional, Protat, Alain, additional, and Delanoe, Julien, additional
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- 2017
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17. Variations of Ice Microphysical Properties in Tropical MCS Using Cloud In-Situ Data and Corresponding Radar Reflectivity Profiles
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Fontaine, Emmanuel, Leroy, Delphine, Schwarzenboeck, Alfons, Coutris, Pierre, Delanoë, Julien, Protat, Alain, Dezitter, Fabien, Calmels, Alice, Strapp, John Walter, Lilie, Lyle, Minnis, Patrick, Yost, Christopher R., Laboratoire de météorologie physique (LaMP), Centre National de la Recherche Scientifique (CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS), SPACE - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Australian Bureau of Meteorology [Melbourne] (BoM), Australian Government, Airbus [France], Met Analytics Inc. [Toronto], Science Engineering Associates Inc., NASA Langley Research Center [Hampton] (LaRC), Science Systems and Applications, Inc. [Lanham] (SSAI), Cardon, Catherine, and Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
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[SDU.STU.ME] Sciences of the Universe [physics]/Earth Sciences/Meteorology ,[SDU.STU.ME]Sciences of the Universe [physics]/Earth Sciences/Meteorology - Abstract
International audience; Mesoscale convective systems (MCS) can last several hours or more and affect human societies in different ways. In order to predict and identify hazardous weather (e. g. in view of aviation safety) linked to MCS, numerical weather forecast and active/passive remote sensing products are currently the most useful tools. A major obstacle to increasing the accuracy of those tools is the fact that cumulonimbus clouds in MCS are composed of liquid droplets and ice hydrometeors (ice crystals); the latter have complex shapes based on diffusional growth, aggregation, and riming, which complicates the interpretation of remote sensing products and increases the uncertainties in numerical weather forecast. In this context, the study presented here investigates the properties of ice hydrometeors in MCS as a function of temperature and horizontal distance from the convective core. For this purpose, ice hydrometeor images, bulk TWC, and simultaneously measured radar reflectivity factors from three airborne campaigns in tropical MCS have been used. The underlying scope of producing these results is to improve the retrieval of MCS microphysical properties from satellite products and also improve cloud parameterizations in numerical weather prediction models.
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- 2016
18. Combining In-situ Measurements, Passive Satellite Imagery, and Active Radar Retrievals for the Detection of High Ice Water Content
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Yost, Christopher R., Minnis, Patrick, Bedka, Kristopher M., Nguyen, Louis, Palikonda, Rabindra, Spangenberg, Douglas, Strapp, John Walter, Delanoë, Julien, Protat, Alain, Cardon, Catherine, Science Systems and Applications, Inc. [Lanham] (SSAI), NASA Langley Research Center [Hampton] (LaRC), NASA, Met Analytics Inc. [Toronto], SPACE - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Australian Bureau of Meteorology [Melbourne] (BoM), and Australian Government
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[SDU.STU.ME] Sciences of the Universe [physics]/Earth Sciences/Meteorology ,[SDU.STU.ME]Sciences of the Universe [physics]/Earth Sciences/Meteorology - Abstract
International audience; At least one hundred jet engine power loss events since the 1990s have been attributed to the phenomenon known as ice crystal icing (ICI). Ingestion of high concentrations of ice particles into aircraft engines is thought to cause these events, but it is clear that the use of current on-board weather radar systems alone is insufficient for detecting conditions that might cause ICI. Passive radiometers in geostationary orbit are valuable for monitoring systems that produce high ice water content (HIWC) and will play an important role in nowcasting, but are incapable of making vertically resolved measurements of ice particle concentration, i.e., ice water content (IWC). Combined radar, lidar, and in-situ measurements are essential for developing a skilled satellite-based HIWC nowcasting technique. The High Altitude Ice Crystals – High Ice Water Content (HAIC-HIWC) field campaigns in Darwin, Australia, and Cayenne, French Guiana, have produced a valuable dataset of in-situ total water content (TWC) measurements with which to study conditions that produce HIWC. The NASA Langley Satellite ClOud and Radiative Property retrieval System (SatCORPS) was used to derive cloud physical and optical properties such cloud top height, temperature, optical depth, and ice water path from multi-spectral satellite imagery acquired throughout the HAIC-HIWC campaigns. These cloud properties were collocated with the in-situ TWC measurements in order to characterize cloud properties in the vicinity of HIWC. Additionally, a database of satellite-derived overshooting cloud top (OT) detections was used to identify TWC measurements in close proximity to convective cores likely producing large concentrations of ice crystals. Certain cloud properties show some sensitivity to increasing TWC and a multivariate probabilistic indicator of HIWC was developed from these datasets. This paper describes the algorithm development and demonstrates the HIWC indicator with imagery from the HAIC-HIWC campaigns. Vertically resolved IWC retrievals from active sensors such as the Cloud Profiling Radar (CPR) on CloudSat and the Doppler Radar System Airborne (RASTA) provide IWC profiles with which to validate and potentially enhance the satellite-based HIWC indicator.
- Published
- 2016
19. Global clear-sky surface skin temperature from multiple satellites using a single-channel algorithm with viewing zenith angle correction
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Scarino, Benjamin R., primary, Minnis, Patrick, additional, Chee, Thad, additional, Bedka, Kristopher M., additional, Yost, Christopher R., additional, and Palikonda, Rabindra, additional
- Published
- 2016
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20. A Prototype Method for Diagnosing High Ice Water Content Probability Using Satellite Imager Data.
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Yost, Christopher R., Bedka, Kristopher M., Minnis, Patrick, Nguyen, Louis, Strapp, J. Walter, Palikonda, Rabindra, Khlopenkov, Konstantin, Spangenberg, Douglas, Smith Jr., William L., Protat, Alain, and Delanoe, Julien
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REMOTE-sensing images , *ICING (Meteorology) , *AIRPLANE motors - Abstract
Recent studies have found that flight through deep convective storms and ingestion of high mass concentrations of ice crystals, also known as high ice water content (HIWC), into aircraft engines can adversely impact aircraft engine performance. These aircraft engine icing events caused by HIWC have been documented during flight in weak reflectivity regions near convective updraft regions that do not appear threatening in onboard weather radar data. Three airborne field campaigns were conducted in 2014 and 2015 to better understand how HIWC is distributed in deep convection, both as a function of altitude and proximity to convective updraft regions, and to facilitate development of new methods for detecting HIWC conditions, in addition to many other research and regulatory goals. This paper describes a prototype method for detecting HIWC conditions using geostationary (GEO) satellite imager data coupled with in-situ total water content (TWC) observations collected during the flight campaigns. Three satellite-derived parameters were determined to be most useful for determining HIWC probability: 1) the horizontal proximity of the aircraft to the nearest overshooting convective updraft or textured anvil cloud, 2) tropopause-relative infrared brightness temperature, and 3) daytime-only cloud optical depth. Statistical fits between collocated TWC and GEO satellite parameters were used to determine the membership functions for the fuzzy logic derivation of HIWC probability. The products were demonstrated using data from several campaign flights and validated using a subset of the satellite-aircraft collocation database. The daytime HIWC probability was found to agree quite well with TWC time trends and identified extreme TWC events with high probability. Discrimination of HIWC was more challenging at night with IR-only information. The products show the greatest capability for discriminating TWC ≥ 0.5 g m-3. Product validation remains challenging due to vertical TWC uncertainties and the typically coarse spatio-temporal resolution of the GEO data. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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21. Comparison of GOES‐retrieved and in situ measurements of deep convective anvil cloud microphysical properties during the Tropical Composition, Cloud and Climate Coupling Experiment (TC4)
- Author
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Yost, Christopher R., primary, Minnis, Patrick, additional, Ayers, J. Kirk, additional, Spangenberg, Douglas A., additional, Heymsfield, Andrew J., additional, Bansemer, Aaron, additional, McGill, Matthew J., additional, and Hlavka, Dennis L., additional
- Published
- 2010
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22. Simulations of Infrared Radiances over a Deep Convective Cloud System Observed during TC4: Potential for Enhancing Nocturnal Ice Cloud Retrievals.
- Author
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Minnis, Patrick, Hong, Gang, Kirk Ayers, J., Smith Jr, William L., Yost, Christopher R., Heymsfield, Andrew J., Heymsfield, Gerald M., Hlavka, Dennis L., King, Michael D., Korn, Errol, McGill, Matthew J., Selkirk, Henry B., Thompson, Anne M., Tian, Lin, and Yang, Ping
- Subjects
CONVECTIVE clouds ,DETECTORS ,ATMOSPHERIC physics ,ICE clouds ,TELECOMMUNICATION satellites - Abstract
Retrievals of ice cloud properties using infrared measurements at 3.7, 6.7, 7.3, 8.5, 10.8, and 12.0 μm can provide consistent results regardless of solar illumination, but are limited to cloud optical thicknesses τ < ∼6. This paper investigates the variations in radiances at these wavelengths over a deep convective cloud system for their potential to extend retrievals of τ and ice particle size D
e to optically thick clouds. Measurements from an imager, an interferometer, the Cloud Physics Lidar (CPL), and the Cloud Radar System (CRS) aboard the NASA ER-2 aircraft during the NASA TC4 (Tropical Composition, Cloud and Climate Coupling) experiment flight during 5 August 2007, are used to examine the retrieval potential of infrared radiances over optically thick ice clouds. Simulations based on coincident in situ measurements and combined cloud τ from CRS and CPL measurements are comparable to the observations. They reveal that brightness temperatures at these bands and their differences (BTD) are sensitive to τ up to ∼20 and that for ice clouds having τ > 20, the 3.7-10.8 μm and 3.7-6.7 μm BTDs are the most sensitive to De. Satellite imagery appears to be consistent with these results suggesting that τ and De could be retrieved for greater optical thicknesses than previously assumed. But, because of sensitivity of the BTDs to uncertainties in the atmospheric profiles of temperature, humidity, and ice water content, and sensor noise, exploiting the small BTD signals in retrieval algorithms will be very challenging. [ABSTRACT FROM AUTHOR]- Published
- 2012
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23. Comparison of GOES-retrieved and in situ measurements of deep convective anvil cloud microphysical properties during the Tropical Composition, Cloud and Climate Coupling Experiment (TC4).
- Author
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Yost, Christopher R., Minnis, Patrick, Ayers, J. Kirk, Spangenberg, Douglas A., Heymsfield, Andrew J., Bansemer, Aaron, McGill, Matthew J., and Hlavka, Dennis L.
- Published
- 2010
- Full Text
- View/download PDF
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