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Richard Essery, Peter Bunting, Aled Rowlands, Nick Rutter, Janet Hardy, Rae Melloh, Tim Link, Danny Marks, and John Pomeroy

remote sensing algorithms, therefore, often include simple representations of radiative transfer in canopies. Variants of Beer’s law or two-stream approximations are generally used (e.g., Sellers et al. 1986 ; Verseghy et al. 1993 ); these treat canopies as horizontally homogeneous turbid media and only predict the average radiation. The radiative environment beneath real canopies, however, is highly heterogeneous because of sun flecks, canopy gaps, and clearings on wide ranges of length scales

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Rafał Wójcik, Konstantinos Andreadis, Marco Tedesco, Eric Wood, Tara Troy, and Dennis Lettenmeier

retrieval of atmospheric moisture in which the SWE problem is incidental. However, even where there is a motivation to update land surface variables, such as SWE, the assimilation of brightness temperatures ( T b ), rather than derived the SWE products, requires knowledge of snow physical properties because they affect the (surface) emissivity. National Centers for Environmental Prediction (NCEP) operational models currently use the Community Radiative Transfer Model (CRTM), which predicts TOA microwave

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S. McKenzie Skiles and Thomas H. Painter

from this time series, and the impact to surface albedo investigated. The regionally specific optical properties of deposited LAP were determined from hemispherical reflectance and particle size distributions using a novel inversion technique ( Skiles et al. 2017 ). We use these measurements in combination with a snow and aerosol radiative transfer model, updated with the site specific dust optical properties, to determine spectral and spectrally integrated radiative forcing by dust and BC in snow

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H. Lievens, A. Al Bitar, N. E. C. Verhoest, F. Cabot, G. J. M. De Lannoy, M. Drusch, G. Dumedah, H.-J. Hendricks Franssen, Y. Kerr, S. K. Tomer, B. Martens, O. Merlin, M. Pan, M. J. van den Berg, H. Vereecken, J. P. Walker, E. F. Wood, and V. R. N. Pauwels

-observed TBs ( Reichle et al. 2001 ; Balsamo et al. 2006 ; Han et al. 2013 ), which circumvents the need for processing soil moisture retrievals. Moreover, this bypasses the need for ancillary parameters (e.g., surface temperature) and allows for the use of consistent parameters (e.g., soil and vegetation) between the LSM and radiative transfer model (RTM). The assimilation of TB observations directly requires the use of an RTM as a forward operator, to simulate the top of the atmosphere (TOA) TB. An

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Gabriëlle J. M. De Lannoy, Rolf H. Reichle, and Valentijn R. N. Pauwels

earlier missions (e.g., AMSR-E at 10.7 GHz). The benefit of using satellite soil moisture retrievals in large-scale data assimilation systems has been shown in multiple studies ( Liu et al. 2011 ; Pan et al. 2012 ). However, only a few studies discussed the direct assimilation of satellite-based Tb at larger scales ( Reichle et al. 2001 ; Balsamo et al. 2006 ). One of the reasons is the complexity of representing radiative transfer processes at the global scale, which will be addressed in this paper

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Matthias Drusch, Thomas Holmes, Patricia de Rosnay, and Gianpaolo Balsamo

this computation are also required in NRT and should be consistent with the first-guess state variables. In the current operational data assimilation system, approximately 18 million satellite observations are used, and the radiative transfer calculations for the model first guess are based on short-range forecasts. Because of the limited time available and the high computational costs of an advanced variational data assimilation system, operational analyses are often produced at a low spatial

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Phillip Harder, Warren D. Helgason, and John W. Pomeroy

surface schemes. The strength of the land–atmosphere coupling has consequences for the radiative terms of the energy balance as changes with snowmelt. The exchange between the snow and stubble surface with the atmosphere demonstrates large energy balance differences with and without stubble ( Fig. 15 ). Exposed stubble increases shortwave absorption, which translates into greater longwave emittance and sensible heat transfer from the surface to the atmosphere. Wheat stubble has a greater stubble

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Clare Webster, Nick Rutter, Franziska Zahner, and Tobias Jonas

‐thinning treatments in a northern mountain headwater basin . Water Resour. Res. , 49 , 936 – 949 , doi: 10.1002/wrcr.20089 . Essery, R. , Pomeroy J. , Ellis C. , and Link T. , 2008a : Modelling longwave radiation to snow beneath forest canopies using hemispherical photography or linear regression . Hydrol. Processes , 22 , 2788 – 2800 , doi: 10.1002/hyp.6930 . Essery, R. , and Coauthors , 2008b : Radiative transfer modeling of a coniferous canopy characterized by airborne remote sensing . J

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Jongyoun Kim and Terri S. Hogue

(see Table 4 ). Particularly, three of the sites (Bondville, Goodwin Creek, and Westville) show a higher correlation ( R 2 = 0.89) and small bias of 0.34 mm day −1 (6% of the mean) at the daily time step. However, performance at the Audubon site (semiarid biome) is less satisfactory ( R 2 = 0.86 and bias = −2.05 mm day −1 at the daily time step). Since this negative bias is transferred from the instantaneous PET estimation, we attribute it to the overestimation of ground heat flux that was

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Ted M. Uecker, Susan D. Kaspari, Keith N. Musselman, and S. McKenzie Skiles

from the air. Raw data were collected using Droplet Measurement Technologies’ SP2 Acquisition Software Version 4.1. Between 5000 and 50 000 particles were recorded to a data file for each sample depending on the sample incandescent concentration (number of particles per cm 3 of sample). BC concentrations were determined using the SP2 toolkit 4000 (Paul Scherrer Institute, Villigen, Switzerland). d. Radiative transfer modeling for albedo and radiative forcing Snow albedo measurements were not made

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