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Reuben Demirdjian, James D. Doyle, Carolyn A. Reynolds, Joel R. Norris, Allison C. Michaelis, and F. Martin Ralph

1. Introduction The predictability of atmospheric rivers (ARs) is vitally important for the management of water resources in California (CA) since it is a densely populated region and highly dependent on the arrival, or lack thereof, of just a handful of precipitation events per year ( Dettinger 2013 ; Ralph et al. 2013 ; Dettinger and Cayan 2014 ; Ralph 2017 ; Lamjiri et al. 2017 , 2018 ). DeFlorio et al. (2018) performed an assessment of global ARs and found that at a 2-day lead time

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Cory Baggett, Sukyoung Lee, and Steven Feldstein

intimately connected to SSW activity and Rossby wave breaking, have a filamentary structure, and rapidly convey moisture poleward, bearing a pronounced resemblance to atmospheric rivers (ARs; Newell et al. 1992 ; Zhu and Newell 1998 ; Neiman et al. 2008 ; Ralph et al. 2004 ; Ralph and Dettinger 2011 ; Newman et al. 2012 ; Krichak et al. 2015 ; Neff et al. 2014 ). Although a myriad of definitions for ARs exist, they are generally characterized by having large values of total column water (>20 kg m

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Johannes M. L. Dahl, Matthew D. Parker, and Louis J. Wicker

near-ground rotation ( Fig. 3 ). By 5220 s, an intense vortex with vertical vorticity ζ exceeding 0.1 s −1 ( Fig. 4 ) has developed at the lowest model level. This vortex is fed by “rivers” of vertical vorticity within the outflow that emanate from downdrafts north and west of the incipient vortex ( Fig. 5 ). Notably, there is an absence of appreciable vertical vorticity east of the cold pool. Our goal was to identify the sources of vertical vorticity within the ζ streamers that originate from

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J. Roads, S. Chen, M. Kanamitsu, and H. Juang

1. Introduction The World Meteorological Organization’s Global Energy and Water Cycle Experiment Continental-Scale International Project (GCIP) is under way. The overall objectives of the multiagency GCIP program, which is being led by the National Oceanic and Atmospheric Administration, are to increase scientific understanding of the hydrologic and energy cycles involved in the complex land–atmosphere–ocean interactions in the Mississippi River basin. Macroscale hydrological models, high

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L. F. Hall

2568JOURNAL OF THE ATMOSPHERIC SCIENCES VOLUME 37NOTES AND CORRESPONDENCEInfrared Thermometer Measurements of the Temperature of the Clouds from the Surface during the 7 March 1970 Total Eclipse L. F. HALL'The Montana Energy and MHD Research and Development Institute, Inc., Butte, MT 59701 10 June 1980 and 11 August 1980ABSTRACTsky during a 15 h period including the total solar eclipse of 7 March 1970 at the Suwannee River StateAn infrared thermometer was used

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Robert G. Fleagle

resultsin a solution which differs markedly from that given by Brunt (1932, 1941) for constant radiation. Groen's(1947) solution is shown to represent the special case of a layer of great thickness. Computations for a valleycontaining a frozen river, light and compact snow, and bare granite indicate that local temperature differences of 1OC or more may occur when radiation is of primary importance.1. IntroductionThe frequent recurrence of nighttime local temperature differences of considerable magnitude

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Annareli Morales, Derek J. Posselt, and Hugh Morrison

1. Introduction Atmospheric rivers (ARs) are synoptic-scale features that transport large amounts of moisture from the tropics to higher latitudes and are critical to the global water cycle ( Zhu and Newell 1998 ; Ralph et al. 2018 ). Over mountainous regions, low-level moist neutral flow associated with ARs can result in heavy precipitation, especially over the upwind mountain slopes ( Roe 2005 ; Houze 2012 ; Ralph and Dettinger 2012 ; Zagrodnik et al. 2018 ). ARs can contribute a large

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Annareli Morales, Derek J. Posselt, Hugh Morrison, and Fei He

tracking algorithm parameters. To our knowledge, the study described herein is the first to use MOAT to analyze simulations of orographic precipitation. Our study focuses on understanding simulated precipitation sensitivities for moist, nearly neutral flow over a 2D bell-shaped mountain. This type of flow is commonly found within wintertime atmospheric rivers (ARs) off the western U.S. coast and allows for little resistance to orographic lift, causing enhanced precipitation over windward mountain

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Liqi Chen, Wei Li, Jianqiong Zhan, Jianjun Wang, Yuanhui Zhang, and Xulin Yang

. This settlement measurement is of particular interest as it has been suggested to have higher aerosol concentrations ( Eckhardt et al. 2013 ; Zhan and Gao 2014 ), and this station is located near the glaciers, which are vulnerable to human perturbation (e.g., additional BC deposition). 2. Methods a. Sampling and measurement of aerosol black carbon The Chinese “Yellow River” Station (YRS) (see Fig. 1 ) is located at Ny-Ålesund. Pollution sources at the Ny-Ålesund settlement including ships

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Shen-Ming Fu, Jian-Hua Sun, Ya-Li Luo, and Yuan-Chun Zhang

1. Introduction Statistical and climatological studies ( Yang et al. 2010 ; Zhang et al. 2015 ) have shown that regions around Dabie Mountain (DBM) over the Yangtze River basin (YRB) in central east China ( Fig. 1a ) are an important vortex source. The vortices originate around DBM, are typically of the meso- α scale ( Orlanski 1975 ), and have been named Dabie vortices (DBVs) ( Fu et al. 2016 ; Zhang et al. 2015 ). This type of vortex is particularly noteworthy, because (i) it has a high

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