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Jicheng Liu, Curtis E. Woodcock, Rae A. Melloh, Robert E. Davis, Ceretha McKenzie, and Thomas H. Painter

as well as canopy structure. As view angles increase away from nadir, less of the ground surface is visible in forested areas. Similarly, as the canopy cover of a forest increases, the VGF will also decrease. A quantitative understanding of these effects requires development of a model for the way the VGF varies as a function of view angle, forest canopy properties, and topography. Prior results indicate a geometric optical (GO) model captures the basic shape of the relationship between the VGF

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Joël Jaffrain and Alexis Berne

, the size, shape, and fall velocity of raindrops are of particular interest. The shape and fall velocity of a raindrop can be accurately derived from its equivolume diameter (e.g., Beard 1977 ; Andsager et al. 1999 ). Therefore, a fundamental property of rainfall for the investigation of its microstructure is the (rain)drop size distribution (DSD). Rain, and hence DSD, is highly variable in time and space at inter- and intraevent scales as well as for different geographic locations ( Tokay and

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R. Uijlenhoet, J.-M. Cohard, and M. Gosset

. A. R. , Meijninger W. M. L. , and Schipper F. , 2002 : Experiences from one-year continuous operation of a large aperture scintillometer over a heterogeneous land surface . Bound.-Layer Meteor. , 105 , 85 – 97 . Bradley, S. G. , Stow C. D. , and Lynch-Blosse C. A. , 2000 : Measurements of rainfall properties using long optical path imaging . J. Atmos. Oceanic Technol. , 17 , 761 – 772 . Cain, J. D. , Rosier P. T. W. , Meijninger W. , and de Bruin H. A. R. , 2001

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Simon R. Osborne and Graham P. Weedon

hydrological properties based on observations and compare them to the UKV values. Section 5 is devoted to discussing the results. Section 5a(1) discusses the JULES output soil moisture and ET compared to observations in 2018 and 2019. Next, water budgets are considered in terms of cumulative plots of observed rainfall and observed- and modeled-ET in 2018 compared to 2019 [ section 5a(2) ]. The progression of the drought in 2018 in terms of greenness, and changes in the size of latent heat errors from

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Eleanor J. Burke, W. James Shuttleworth, and R. Chawn Harlow

relevant atmospheric model and are driven by available observations, rather than output from the atmospheric model. LDAS often give less than perfect simulations of soil-moisture fields because of poor parameterization (e.g., poorly defined soil properties), unknown initial conditions, low-quality forcing data (e.g., poorly defined precipitation fields), or errors in model physics. The assimilation of microwave brightness temperatures ( T B ) into LDAS potentially provides a way of improving the

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Massimiliano Ignaccolo and Carlo De Michele

ζ p of Eq. (2) is small independently from site and synoptic condition. Then, we consider two additional sites: one with a 2DVD disdrometer (1699 one-minute counts), and one with a Thies optical disdrometer (18 911 one-minute counts). With these additional datasets, we show that the form factor ζ p is small independently from the instrumentation used to “measure” the rainfall phenomenon. Finally, while the 2DVD and Thies disdrometers directly report the drop velocity, no velocity

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Li Fang, Xiwu Zhan, Jifu Yin, Jicheng Liu, Mitchell Schull, Jeffrey P. Walker, Jun Wen, Michael H. Cosh, Tarendra Lakhankar, Chandra Holifield Collins, David D. Bosch, and Patrick J. Starks

also been found sensitive to SM. Examples are the C-band radar backscatter from ESA Sentinel-1A and land surface temperature (LST), albedo ( A ), and vegetation indices (VI) from various optical/thermal sensors (such as GOES, VIIRS, MODIS, and AVHRR). Attempts to generate SM data products from these satellite observations have been well documented [e.g., Sabel et al. (2007) using scanning synthetic aperture radar (ScanSAR) sigma data on Envisat ; Carlson (2007) using thermal and NDVI

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Nasrin Nasrollahi, Kuolin Hsu, and Soroosh Sorooshian

of satellite precipitation products, including reducing their false alarm ratio (FAR; Sorooshian et al. 2011 ). The utility of multispectral satellite data in capturing microphysical properties of clouds and improving precipitation estimation has been the subject of many investigations in recent years. For instance, Li et al. (2007) showed the effectiveness of MODIS channel 31 (11.03 μ m) in identifying high clouds with very cold brightness temperatures. Strabala et al. (1994) show that for

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Hernan A. Moreno, Enrique R. Vivoni, and David J. Gochis

). Distributed hydrologic models are designed to continually ingest high-quality rainfall estimates and forecasts, allowing for real-time flood forecasting using information about future rainfall ( Garrote and Bras 1995 ; Vivoni et al. 2006 ; Collier 2007 ). The distributed nature of these types of hydrologic models permits exploring the spatial properties of the basin response relative to the spatiotemporal evolution of precipitation forcing. For example, the streamflow properties can be assessed as a

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Anna-Maria Tilg, Flemming Vejen, Charlotte Bay Hasager, and Morten Nielsen

) provided access to precipitation, wind, and temperature measurements from February 2012 to December 2017 (6 years). Table 1 provides a detailed overview of the instrumentation. The focus of our analyses is on the Thies Laser Precipitation Monitor (LPM) disdrometer data. Table 1. Instrumentation at field site Voulund, Denmark. The LPM disdrometer is an optical disdrometer manufactured by the company Adolf Thies GmbH and Co. KG in Germany. The precipitation particles attenuate the laser sheet between

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