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Eric A. Smith

-balanced diurnal regularity. It is shown how the radiation budget of the surface is modulatedby basic differences in the shortwave (VIS) and near-infrared (NIR) solar spectrum. More than 2:1 differencesare noted in the NIR and VIS surface albedos. Diurnal averages of the surface and parameters illustrate significantday-night differences associated with the diurnal pulsation of the heat low vortex. Day-night differences insurface temperature are extreme; close to 50-C. It is shown that the diurnal amplitude of

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Ismail Yucel, W. James Shuttleworth, X. Gao, and S. Sorooshian

directly into the, fifth-generation Pennsylvania State University–National Center for Atmospheric Research (PSU–NCAR) Mesoscale Model (MM5). Clouds are distributed in the vertical starting from the cloud top, which is derived from the infrared band of GOES. The impact on the model's ability to diagnose surface radiation and precipitation fields was investigated through comparisons between observed and modeled data, with and without cloud ingestion, for the period 14–15 July 1999, when there were

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Stephen Marvill and K. O. L. F. Jayaweera

aresignificantly modified by valley wind episodes. The infrared sensor on the NOAA polar orbiting satelliteclearly detects this warming and delineates the exact area covered by valley winds. Satellite IR imageswere used in conjunction with surface and upper air maps, radiosonde data, and pilot reports to analyze twovalley wind episodes during early 1975. Clear weather allowed excellent satellite viewing and strong temperature contrasts, because of strong radiational cooling in non-windy valley locations. In

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Linette N. Boisvert, Alek A. Petty, and Julienne C. Stroeve

entire Arctic. (b),(c) The BaKa region is given by the dashed black box. (b) Sea ice extent for 1 Jan 2016 and (c) sea ice extent for January 2016 (monthly mean of daily extent). The magenta line in (b) and (c) indicates the median sea ice extent for 1981–2010. In winter, cyclones are thought to be the main transporter of heat and moisture into the Arctic ( Sorteberg and Walsh 2008 ), and could, therefore, contribute to sea ice melt in the absence of solar radiation. The changing magnitude and

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David A. Short and Robert F. Cahalan

monthly averaged outgoing infrared radiation (IR, from the NOAApolar orbiting satellites) is observed to be larger during summer than during winter over the north PacificOcean. A statistical analysis of the daily observations shows the daily variance to be similar during bothseasons while the autocorrelation function is quite different. This leads to a seasonal difference in estimatesof the climatic noise level, i.e., the variances expected in summer and winter monthly averages due to thenumber of

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Richard M. Forbes and Maike Ahlgrimm

the longwave spectrum than ice, and the clouds’ albedo increases in the presence of liquid drops (e.g., Hogan et al. 2003 ). Thus, an accurate representation of the mixed phase is critical to model the cloud–radiation interaction correctly and reduce uncertainty in weather and climate predictions. This is particularly true in areas with extensive persistent mixed-phase boundary layer clouds at high latitudes such as found in the Arctic ( Morrison et al. 2012 ) and over the Southern Hemisphere

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John D. Horel

annual cycles in windspeed and pressure gradient are shown to be kinematically consistent. The annual cycles in rainfall, surfacewind convergence, and satellite-derived outgoing infrared radiation and albedo exhibit many similarities inthe regions dominated by tropical convection.1. Introduction For many years, the annual cycles in temperature,rainfall and pressure measured at stations around theglobe have been studied in order to classify regionalclimates (e.g., KiSppen, 1923; Kendrew, 1937

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David H. Bromwich, Yang Du, and Keith M. Hines

three-dimensionalmesoscale numerical model. It is shown that the simulated winds blow from the broad gently sloped interior tothe steep coastal margins. This general wind pattern is similar to that found over Antarctica due to the samegoverning dynamics. The longwave radiational cooling of the sloping ice terrain is the key driving force of thiscold airflow. In some coastal areas the downslope winds converge into large fjords, such as Kangerlussuaq andSermilik. This is consistent with the frequent

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G. Brogniez, J. C. Buriez, V. Giraud, F. Parol, and C. Vanbauce

. Atmos. Sci., 26, 138-147.Parol, F., J. C. Buriez, G. Brogniez, and Y. Fouquart, 1991: Infor mation content of AVHRR channels 4 and 5 with respect to the effective radius of cirrus cloud particles. J. Appl. Meteor., 30, 973-984.Platt, C. M. R., 1971: A narrow-beam radiometer for atmospheric radiation studies. J. Appl. Meteor., 10, 1307-1313.--, 1973: Lidar and radiometric observations of cirrus clouds. J. Atmos. Sci., 30, 1191 - 1204.--, 1975: Infrared emissivity cirrus

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David A. Short and John M. Wallace

1160 MONTHLY WEATHER REVIEW Vot. tJME I08Satellite-Inferred Morning-to-Evening Cloudiness Changes~ DAVID A. SHORT2 AND JOHN M. WALLACEDepartment of Atmospheric Sciences AK-40, University of Washington, Seattle 98195Manuscript received 25 June 1979, in final form 9 April 1980) ABSTRACT Outgoing infrared radiation (IR) values inferred from radiance measurements

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