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S. Zhong and J. C. Doran

this paper we use observations and a three-dimensional numerical model to study the effects of inhomogeneous surface fluxes on the boundary layer characteristics of a 300 km × 350 km area in Oklahoma and Kansas. In particular, we consider the effects of spatially varying fluxes on the formation of boundary layer clouds, and we also discuss their effects on the depth of the boundary layer and the vertical profiles of potential temperature and mixing ratio. We show that under the settled weather

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Evan Weller, Kay Shelton, Michael J. Reeder, and Christian Jakob

1. Introduction Although rainfall is intermittent in both time and space, its timing and location are intimately tied to vertical motion, and the internal circulation of weather systems commonly provides this vertical motion ( Birch et al. 2014a ; Bony et al. 2015 ). For this reason, variations in the frequency, structure, or intensity of weather systems exert a strong control on the variability of rainfall. Moreover, the convergence of mass in the low-level boundary layer plays an important

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Andrew M. Carleton, David L. Arnold, David J. Travis, Steve Curran, and Jimmy O. Adegoke

, we developed two complementary and related measures for classifying daily background flow over the CCB. Specifically for the 1999 and 2000 study summers, and given that the CCB’s major axis is oriented west–east—paralleling the typical movement of weather systems in the Midwest—the first measure involves the spatial range of vector wind speed values in the midtroposphere (500 hPa), or V (500) ( Table 1 ). Each day’s V (500) was determined visually as a temporal average of the individual 12-h (i

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M. Wang, M. Wagner, G. Miguez-Macho, Y. Kamarianakis, A. Mahalov, M. Moustaoui, J. Miller, A. VanLoocke, J. E. Bagley, C. J. Bernacchi, and M. Georgescu

section 3 . In this section, model results are evaluated against observational data, aimed at identifying an optimal model configuration for reproducing near-surface climate conditions. Following model evaluation, hydroclimatic impacts of perennial bioenergy crop deployment are assessed. Concluding remarks and suggestions for future work are discussed in section 4 . 2. Methodology We used the Weather Research and Forecasting Model version 3.6.1 (hereafter WRF) ( Skamarock et al. 2008 ). WRF is a

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Tsing-Chang Chen, Wan-Ru Huang, and Ming-Cheng Yen

the southern part of East Asia is established by a transition from the early summer mei-yu regime into the late summer tropical cyclone season through a break in monsoon rains during late June and early July. A depiction of this monsoon life cycle with Taiwan rainfall is presented in Fig. 1a [a modification of Chen et al.’s (2004) Fig. 6a]. The transition of monsoon rainfall regimes is caused by the sequential passage of the mei-yu rainband in early summer, the western Pacific subtropic high

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Gary M. Lackmann, Rebecca L. Miller, Walter A. Robinson, and Allison C. Michaelis

1. Introduction Changes in weather extremes are a societally impactful manifestation of climate change. Several types of extreme weather can be associated with persistent anomalies (PAs 1 ) in the midlatitude tropospheric flow. PAs can be associated with droughts (e.g., Dole et al. 2011 ), pluvials (e.g., Hong et al. 2011 ), heat waves (e.g., Matsueda 2011 ; Horton et al. 2016 ), and cold-air outbreaks (e.g., Carrera et al. 2004 ); these events can occur in all seasons and in diverse

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John R. Lanzante, Stephen A. Klein, and Dian J. Seidel

system, articulated by Karl et al. (1995) and promulgated by the National Research Council ( NRC 1999 ). Those tenets of climate observing systems set forth system design and maintenance principles, operating procedures, and data and metadata analysis and archival policies that would vastly improve the long-term continuity and quality of climate datasets. Because they were initiated primarily to support weather forecasting rather than climate monitoring, existing upper-air temperature observing

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M. Segal, M. J. Mitchell, and R. W. Arritt

supportive of the potential for development of local deep convection, as itcontributes to increased surface evaporation. In contrast, the larger increase in the air temperature corn * Current Affiliation: Department of Agronomy, Iowa State University, Ames, Iowa. ** Current Affiliation: National Weather Service, Minneapolis,Minnesota. Corresponding author address.' Moti Segal, Department of Agronomy, Iowa State University, Ames, IA 50011.© 1994 American Meteorological Societypared with SST

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Anthony R. Hansen, Joseph P. Pandolfo, and Alfonso Sutera

persistent flow patterns (or flow regimes) in the large-scalemidlatitude circulation was noted soon after the deployment of extensive, synoptically scheduled, upperair soundings in the Northern Hemisphere (NH)(Rossby et al. 1939; Namias 1947; Elliot and Smith1949; Rex 1950a,b, 1951; Baur 1951, etc.). These earlystudies were motivated in part by the hope that theexistence of such flow regimes could be an aid to extended-range weather forecasting (e.g., Baur 1951; Elliot 1951 ) based on the impression that

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R. A. Stuart and G. A. Isaac

of primary importance in any analysis of the practical impacts of anarea's climatology. Increasing concentrations of carbondioxide and other greenhouse gases are anticipated tohave important effects on both these weather parameters over the next few decades. Temperatures are expected to increase, while precipitation amounts showboth increases or decreases depending on the geographic location and season. These expectations arebased on simulations of the global climate by generalcirculation models

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