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G. Delgado, Luiz A. T. Machado, Carlos F. Angelis, Marcus J. Bottino, Á. Redaño, J. Lorente, L. Gimeno, and R. Nieto

1. Introduction Several studies have focused on the rainfall estimation using infrared–visible (IR–VIS) imagery highlighting its importance due to the low sampling of the ground-based radars and the sparse distribution of the rain gauges. Estimations by satellite provide high spatial and temporal sampling frequencies, but the information is inferred through indirect methods, which result in significant errors in the final rainfall estimation. Previous works discuss the use of satellite rainfall

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Michael F. Donovan, Earle R. Williams, Cathy Kessinger, Gary Blackburn, Paul H. Herzegh, Richard L. Bankert, Steve Miller, and Frederick R. Mosher

thunderstorms. The updraft is a key internal variable in its influence on many aviation hazards (turbulence, icing, hail, and lightning). These internal measurements are generally augmented with satellite observations—an important surveillance tool, but one that reveals only the exterior characteristics of clouds (e.g., IR cloud temperature, cloud height), owing to the opaque nature of convective clouds in the visible and infrared region. The present study shifts the focus in hazardous weather from land to

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Yi Huang, Stephen S. Leroy, and James G. Anderson

advantage of the infrared (IR) spectral features of climate forcings of greenhouse gases and feedbacks of temperature, water vapor, and clouds and quantifies each of them by partitioning the total change in the outgoing longwave radiation (OLR) spectrum. One limitation of this method when applied to IR spectral measurement, however, is the ambiguity issue. Some feedbacks have similar infrared spectral fingerprints: when their fingerprints are obscured by uncertainties, it becomes difficult to quantify

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Michael S. Town, Von P. Walden, and Stephen G. Warren

, and therefore the longwave upwelling flux. The effect of the shortwave cloud radiative forcing is not directly correlated with the longwave cloud radiative forcing because cloud optical depth differs significantly between visible and infrared wavelengths for the same liquid water path, particle size, and phase. Therefore, the relationships between LUF min , clear-sky LUF, and cloudy-sky LUF are more variable when insolation is substantial than when longwave radiation dominates the radiation budget

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Martha C. Anderson, Christopher Hain, Brian Wardlow, Agustin Pimstein, John R. Mecikalski, and William P. Kustas

thermal infrared (TIR) atmospheric window channel (∼10.7 μ m) are combined with shortwave information about vegetation cover fraction to directly diagnose evaporative fluxes at 5–10-km spatial resolution ( Anderson et al. 2007c ). Because the ESI does not use rainfall data, it provides an independent check on precipitation-based drought indicators and may be more robust in regions with minimal ground-based meteorological infrastructure. The remotely sensed ET fields have the advantage that they

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John R. Mecikalski, Wayne M. MacKenzie Jr., Marianne König, and Sam Muller

. , M. König , and S. Muller , 2010 : Cloud-top properties of growing cumulus prior to convective initiation as measured by Meteosat Second Generation. Part I: Infrared fields. J. Appl. Meteor. Climatol. , 49 , 521 – 534 . Nakajima , T. , and M. D. King , 1990 : Determination of the optical thickness and effective particle radius of clouds from reflected solar radiation measurements. Part I: Theory. J. Atmos. Sci. , 47 , 1878 – 1893 . Purdom , J. F. W. , 1976 : Some uses of

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Franz Schreier

misunderstanding about the Voigt line profile.” In this note we continue this discussion on some of the points raised in this paper. 2. Definitions For the infrared and microwave spectral region, the combined effect of pressure (collision) broadening corresponding to a Lorentzian line shape (with a half-width proportional to pressure, γ L ∼ p ) and Doppler broadening corresponding to a Gaussian line shape (with a half-width depending on line position ν̂ and temperature γ D ∼ ν̂ T ) can be modeled by

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S. J. Bolsenga

desirable,sensor nadir angles.3. Conclusion This note has presented a simplified diagram (Fig. 1)which allows the mode of TIROS radiation sensoroperation (including which sensor is in use), and theapproximate perinadir nadir angles during the dataswaths, to be determined. All required input data arecontained on the maps of subpoint track or in theFMRT Index, as presented in the various TIROSradiation catalogues. Thus, if a research worker wishesto consider the use of infrared data from the TIROSVII

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T. H. Cheng, X. F. Gu, L. F. Chen, T. Yu, and G. L. Tian

( Rolland et al. 2000 ). Many research efforts have focused on the polarization characteristics of atmosphere radiation. It was shown that the polarization characteristics in the visible and near-infrared spectral region contain a wealth of information that is useful for the retrieval of cloud and aerosol properties ( Hansen 1971 ; Chepfer et al. 1998 , 1999 ). Liou and Takano (2002) demonstrated that information of ice crystal shape and crystal orientation can be inferred from the reflected

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Michel Viollier, Carsten Standfuss, Olivier Chomette, and Arnaud Quesney

1. Introduction During the last decades, two National Aeronautics and Space Administration (NASA) missions [Earth Radiation Budget Experiment (ERBE; Barkstrom et al. 1989 ) and Clouds and the Earth’s Radiant Energy System (CERES; Wielicki et al. 1996 )] have been devoted to the estimation of the earth radiation budget (ERB). Additional contributions have also been provided by the Scanner for Radiation Budget (ScaRaB; Kandel et al. 1998 ; Duvel et al. 2001 ) and Geostationary Earth Radiation

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