Search Results

You are looking at 1 - 8 of 8 items for :

  • Radiative fluxes x
  • The Cold Land Processes Experiment (CLPX) x
  • All content x
Clear All
Janet Hardy, Robert Davis, Yeohoon Koh, Don Cline, Kelly Elder, Richard Armstrong, Hans-Peter Marshall, Thomas Painter, Gilles Castres Saint-Martin, Roger DeRoo, Kamal Sarabandi, Tobias Graf, Toshio Koike, and Kyle McDonald

the LSOS consisted of a high sampling density within relatively uniform areas of the LSOS to facilitate a comparison of microwave remote sensing data, radiative transfer models, detailed physical models of the snow and the underlying soil, and ground observations. A network of footpaths was established throughout the LSOS to prevent the disruption of the specific measurement sites. 2. Summary of collected data parameters a. Canopy characterization In the fall of 2001, Cold Regions Research and

Full access
D. Marks, A. Winstral, G. Flerchinger, M. Reba, J. Pomeroy, T. Link, and K. Elder

; Pomeroy et al. 1998 ). In general, the energy balance of a snow cover is expressed as where Δ Q is change in snow cover energy, and R n , H , L υ E , G and M are net radiative, sensible, latent, conductive, and advective energy fluxes (all terms are in W m −2 ), respectively; L υ is the latent heat of vaporization or sublimation (J kg −1 ) and E is the mass flux by sublimation from or condensation to the snow surface (kg m −2 s −1 ). In this context, advected energy M is heat lost

Full access
Nick Rutter, Don Cline, and Long Li

fluxes to the snowpack than SNTHERM, which created less meltwater. The specific reasons for the different behaviors between energy fluxes and meltwater production in the two models are unknown. Although both were forced with the same hydrometeorological data over a wide range of physical settings influencing radiative and turbulent energy exchange, small differences between the model representations of liquid water, and perhaps differences in layer structure, were sufficient to cause divergence

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

1. Introduction Forest canopies strongly modify radiative fluxes reaching the underlying surface. This has important implications for hydrological and ecological processes, such as snowmelt and succession, in forested environments ( Pomeroy and Dion 1996 ; Battaglia et al. 2002 ; Hardy et al. 2004 ). Conversely, radiation reflected and emitted from trees complicates the retrieval of forest snow properties by remote sensing ( Chang et al. 1996 ; Klein et al. 1998 ). Land surface models and

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

temperature. The layer interfaces are assumed to be planar. The sandwich model, based on multiple scattering radiative transfer, is used ( Wiesmann et al. 1998 ) to combine internal scattering and reflections at the interfaces. Internal volume scattering is accounted for by a two-flux model (up- and downwelling streams) derived from a six-flux approach (fluxes in all spatial directions). The absorption and scattering coefficients are functions of the six-flux parameters. The absorption coefficient can be

Full access
Kelly Elder, Angus Goodbody, Don Cline, Paul Houser, Glen E. Liston, Larry Mahrt, and Nick Rutter

using up- and down-looking pyranometers and pyrgeometers for shortwave and longwave, respectively. Pyrgeometers were also deployed at 4 and 25 m above the ground surface to evaluate longwave radiative flux divergence. Soil measurements include three levels of temperature (0.025, 0.05, and 0.10 m), two levels of moisture (0.05 and 0.10 m), and a heat flux measurement at 0.10 m. A probe capable of measuring thermal properties of the soil was installed to determine heat capacity and thermal

Full access
Don Cline, Simon Yueh, Bruce Chapman, Boba Stankov, Al Gasiewski, Dallas Masters, Kelly Elder, Richard Kelly, Thomas H. Painter, Steve Miller, Steve Katzberg, and Larry Mahrt

(0.1 m). Observations were made in the ISAs, the local scale observation site (LSOS), and at a site adjacent to the National Center for Atmospheric Research (NCAR) flux tower (close to the southeast corner of the Potter Creek ISA; Fig. 1 ; Table 2 ). Data were collected on 8–9 April (snow-covered sites) and 18–19 September 2003 (snow-free sites). Data are available for all sites except for snow depth contours at the site adjacent to the NCAR flux tower. Elevation data were acquired from

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

) results from the Moderate Resolution Imaging Spectroradiometer (MODIS) snow-covered area and grain size (MODSCAG) model for the Cold Land Processes Field Experiment (CLPX) in the St. Louis Creek intensive study area (ISA) of the Fraser Experimental Forest. MODSCAG combines a radiative transfer model for snow spectral endmembers with a multiple endmember spectral mixture analysis approach in which the number of endmembers as well as the endmembers themselves may vary on a pixel by pixel basis. When

Full access