Dew Formation, Eddy-Correlation Latent Heat Fluxes, and the Surface Energy Imbalance at Cabauw During Stable Conditions

Roode, Stephan R. de; Bosveld, Fred C.; Kroon, P.S.

doi:10.1007/s10546-010-9476-1

Cited by 30 publications

(22 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Upward radiation fluxes are derived from older instruments having somewhat higher uncertainties: 2 % for shortwave and 5 W m −2 for longwave radiation. Failure in closing the surface energy budget from micrometeorological observations (Oncley et al 2007;Foken 2008 andRoode et al 2010) forces us to attribute a large uncertainty to the observed surface heat fluxes. For daytime, the uncertainty is typically 10-15 % of the available energy.…”

Section: Models and Observationsmentioning

confidence: 99%

The Third GABLS Intercomparison Case for Evaluation Studies of Boundary-Layer Models. Part B: Results and Process Understanding

Bosveld

Baas

Steeneveld

et al. 2014

Boundary-Layer Meteorol

Self Cite

106

View full text Add to dashboard Cite

We describe and analyze the results of the third global energy and water cycle experiment atmospheric boundary layer Study intercomparison and evaluation study for F. C. Bosveld (B) · P. Baas · E. I. F. single-column models. Each of the nineteen participating models was operated with its own physics package, including land-surface, radiation and turbulent mixing schemes, for a full diurnal cycle selected from the Cabauw observatory archive. By carefully prescribing the temporal evolution of the forcings on the vertical column, the models could be evaluated against observations. We focus on the gross features of the stable boundary layer (SBL), such as the onset of evening momentum decoupling, the 2-m minimum temperature, the evolution of the inertial oscillation and the morning transition. New process diagrams are introduced to interpret the variety of model results and the relative importance of processes in the SBL; the diagrams include the results of a number of sensitivity runs performed with one of the models. The models are characterized in terms of thermal coupling to the soil, longwave radiation and turbulent mixing. It is shown that differences in longwave radiation schemes among the models have only a small effect on the simulations; however, there are significant variations in downward radiation due to different boundary-layer profiles of temperature and humidity. The differences in modelled thermal coupling to the land surface are large and explain most of the variations in 2-m air temperature and longwave incoming radiation among models. Models with strong turbulent mixing overestimate the boundary-layer height, underestimate the wind speed at 200 m, and give a relatively large downward sensible heat flux. The result is that 2-m air temperature is relatively insensitive to turbulent mixing intensity. Evening transition times spread 1.5 h around the observed time of transition, with later transitions for models with coarse resolution. Time of onset in the morning transition spreads 2 h around the observed transition time. With this case, the morning transition appeared to be difficult to study, no relation could be found between the studied processes, and the variation in the time of the morning transition among the models.

show abstract

Section: Models and Observationsmentioning

confidence: 99%

The Third GABLS Intercomparison Case for Evaluation Studies of Boundary-Layer Models. Part B: Results and Process Understanding

Bosveld

Baas

Steeneveld

et al. 2014

Boundary-Layer Meteorol

Self Cite

106

View full text Add to dashboard Cite

show abstract

“…ET act estimated with this method was on average 4 % higher than ET pot during well-watered conditions (meaning that the storage deficit was below 100 mm). Overestimation of the daily evapotranspiration sum may be caused by an underestimation of dew formation at night (De Roode et al, 2010). As a quick fix, we divided ET act by 1.04.…”

Section: C Brauer Et Al: Application Of Walrus To Two Contrastinmentioning

confidence: 99%

The Wageningen Lowland Runoff Simulator (WALRUS): application to the Hupsel Brook catchment and the Cabauw polder

Brauer

Torfs

Teuling

et al. 2014

Hydrol. Earth Syst. Sci.

View full text Add to dashboard Cite

Abstract. The Wageningen Lowland Runoff Simulator (WALRUS) is a new parametric (conceptual) rainfall-runoff model which accounts explicitly for processes that are important in lowland areas, such as groundwater-unsaturated zone coupling, wetness-dependent flowroutes, groundwatersurface water feedbacks, and seepage and surface water supply (see companion paper by Brauer et al., 2014). Lowland catchments can be divided into slightly sloping, freely draining catchments and flat polders with controlled water levels. Here, we apply WALRUS to two contrasting Dutch catchments: the Hupsel Brook catchment and the Cabauw polder. In both catchments, WALRUS performs well: Nash-Sutcliffe efficiencies obtained after calibration on 1 year of discharge observations are 0.87 for the Hupsel Brook catchment and 0.83 for the Cabauw polder, with values of 0.74 and 0.76 for validation. The model also performs well during floods and droughts and can forecast the effect of control operations. Through the dynamic division between quick and slow flowroutes controlled by a wetness index, temporal and spatial variability in groundwater depths can be accounted for, which results in adequate simulation of discharge peaks as well as low flows. The performance of WALRUS is most sensitive to the parameter controlling the wetness index and the groundwater reservoir constant, and to a lesser extent to the quickflow reservoir constant. The effects of these three parameters can be identified in the discharge time series, which indicates that the model is not overparameterised (parsimonious). Forcing uncertainty was found to have a larger effect on modelled discharge than parameter uncertainty and uncertainty in initial conditions.

show abstract

“…The eddy covariance water vapor flux was biased low in saturation conditions because of the poor frequency response of its open-path analyzer (Roode et al 2010). To circumvent the problem, we used the gradient diffusion method to determine the water vapor flux above the canopy.…”

Section: Nighttime Water Vapor Flux Under Saturation Conditionsmentioning

confidence: 99%

Dew water isotopic ratios and their relationships to ecosystem water pools and fluxes in a cropland and a grassland in China

et al. 2011

View full text Add to dashboard Cite

Dew formation has the potential to modulate the spatial and temporal variations of isotopic contents of atmospheric water vapor, oxygen and carbon dioxide. The goal of this paper is to improve our understanding of the isotopic interactions between dew water and ecosystem water pools and fluxes through two field experiments in a wheat/maize cropland and in a short steppe grassland in China. Measurements were made during 94 dew events of the D and (18)O compositions of dew, atmospheric vapor, leaf, xylem and soil water, and the whole ecosystem water flux. Our results demonstrate that the equilibrium fractionation played a dominant role over the kinetic fractionation in controlling the dew water isotopic compositions. A significant correlation between the isotopic compositions of leaf water and dew water suggests a large role of top-down exchange with atmospheric vapor controlling the leaf water turnover at night. According to the isotopic labeling, dew water consisted of a downward flux of water vapor from above the canopy (98%) and upward fluxes originated from soil evaporation and transpiration of the leaves in the lower canopy (2%).

show abstract

Dew Formation, Eddy-Correlation Latent Heat Fluxes, and the Surface Energy Imbalance at Cabauw During Stable Conditions

Cited by 30 publications

References 25 publications

The Third GABLS Intercomparison Case for Evaluation Studies of Boundary-Layer Models. Part B: Results and Process Understanding

The Third GABLS Intercomparison Case for Evaluation Studies of Boundary-Layer Models. Part B: Results and Process Understanding

The Wageningen Lowland Runoff Simulator (WALRUS): application to the Hupsel Brook catchment and the Cabauw polder

Dew water isotopic ratios and their relationships to ecosystem water pools and fluxes in a cropland and a grassland in China

Contact Info

Product

Resources

About