Inhomogeneity of the Land Surface and Problems in theParameterization of Surface Fluxes in Natural Conditions

Panin, G. N.; Tetzlaff, G.; Raabe, Armin

doi:10.1007/s007040050041

Cited by 84 publications

(49 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…If the landscape is very heterogeneous at a relevant scale, the budget cannot be closed at the small scales of typical local flux measurements but only at the landscape scale. This means that earlier studies of the heterogeneity aspect (Finnigan et al 2003;Panin et al 1998) showed the right direction, but these investigations basically suggested an influence of the heterogeneities in the immediate neighbourhood of the measurement site and not a contribution from larger heterogeneities at the landscape scale, which are necessary for the generation of secondary circulations.…”

Section: Discussionmentioning

confidence: 77%

“…The non-closure of the energy balance was also explained by the heterogeneity of the land surface (Panin et al 1998). These authors assumed that the heterogeneity in the vicinity of a flux-measurement site generates eddies at larger time scales, but such turbulent structures generated by heterogeneities close to the measuring tower can be measured with the eddy-covariance method Zhang et al 2007).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Energy balance closure for the LITFASS-2003 experiment

Foken

Mauder

Liebethal

et al. 2009

Theor Appl Climatol

140

108

View full text Add to dashboard Cite

In the first part, this paper synthesises the main results from a series of previous studies on the closure of the local energy balance at low-vegetation sites during the LITFASS-2003 experiment. A residual of up to 25% of the available energy has been found which cannot be fully explained either by the measurement uncertainty of the single components of the surface energy balance or by the length of the flux-averaging period. In the second part, secondary circulations due to heterogeneities in the surface characteristics (roughness, thermal and moisture properties) are discussed as a possible cause for the observed energy balance non-closure. This hypothesis seems to be supported from the fluxes derived from area-averaging measurement techniques (scintillometers, aircraft).

show abstract

Section: Discussionmentioning

confidence: 77%

mentioning

confidence: 99%

Energy balance closure for the LITFASS-2003 experiment

Foken

Mauder

Liebethal

et al. 2009

Theor Appl Climatol

140

108

View full text Add to dashboard Cite

show abstract

“…The lack of closure of the energy balance in the land surface experiments given in Table 1 was interpreted by Foken (1998) as an effect of the fractional coverage of vegetation and the influence of the soil heat storage. The imbalance was attributed by Panin et al (1998) to the influence of heterogeneities in the surrounding area and by Twine et al (2000) to unknown problems with the sensible and/or latent heat flux measurements. Finnigan et al (2003) focused on the problem of inadequate temporal averaging (which would lose low-frequency contributions) for the turbulent fluxes, perhaps related to non-homogeneous surfaces.…”

Section: Introductionmentioning

confidence: 99%

The Energy Balance Experiment EBEX-2000. Part I: overview and energy balance

Oncley

Foken

Vogt

et al. 2007

Boundary-Layer Meteorol

340

272

View full text Add to dashboard Cite

An overview of the Energy Balance Experiment (EBEX-2000) is given. This experiment studied the ability of state-of-the-art measurements to close the surface energy balance over a surface (a vegetative canopy with large evapotranspiration) where closure has been difficult to obtain. A flood-irrigated cotton field over uniform terrain was used, though aerial imagery and direct flux measurements showed that the surface still was inhomogeneous. All major terms of the surface energy balance were measured at nine sites to characterize the spatial variability across the field. Included in these observations was an estimate of heat storage in the plant canopy. The resultant imbalance still was 10%, which exceeds the estimated measurement error. We speculate that horizontal advection in the layer between the canopy top and our flux measurement height may cause this imbalance, though our estimates of

show abstract

“…It has been demonstrated that landscape heterogeneity has a significant impact on measurement and interpretation of atmospheric data at a single point in space. Panin et al (1998) and Panin and Tetzlaff (1999) related energy balance closure problems due to underestimation of turbulent fluxes to length scales of landscape inhomogeneity. Schmid and Lloyd (1999) showed potential errors in flux measurements over inhomogeneous terrain due to non-representative footprints, a sensor location bias that had to be taken into account to derive ecosystem scale fluxes from local measurements.…”

Section: Introductionmentioning

confidence: 99%

Quality control of CarboEurope flux data – Part 1: Coupling footprint analyses with flux data quality assessment to evaluate sites in forest ecosystems

et al. 2008

View full text Add to dashboard Cite

Abstract. We applied a site evaluation approach combining Lagrangian Stochastic footprint modeling with a quality assessment approach for eddy-covariance data to 25 forested sites of the CarboEurope-IP network. The analysis addresses the spatial representativeness of the flux measurements, instrumental effects on data quality, spatial patterns in the data quality, and the performance of the coordinate rotation method. Our findings demonstrate that application of a footprint filter could strengthen the CarboEurope-IP flux database, since only one third of the sites is situated in truly homogeneous terrain. Almost half of the sites experience a significant reduction in eddy-covariance data quality under certain conditions, though these effects are mostly constricted to a small portion of the dataset. Reductions in data quality of the sensible heat flux are mostly induced by characteristics of the surrounding terrain, while the latent heat flux is subject to instrumentation-related problems. The Planar-Fit coordinate rotation proved to be a reliable tool for the majority of the sites using only a single set of rotation angles. Overall, we found a high average data quality for the CarboEurope-IP network, with good representativeness of the measurement data for the specified target land cover types.

show abstract

Inhomogeneity of the Land Surface and Problems in theParameterization of Surface Fluxes in Natural Conditions

Cited by 84 publications

References 23 publications

Energy balance closure for the LITFASS-2003 experiment

Energy balance closure for the LITFASS-2003 experiment

The Energy Balance Experiment EBEX-2000. Part I: overview and energy balance

Quality control of CarboEurope flux data – Part 1: Coupling footprint analyses with flux data quality assessment to evaluate sites in forest ecosystems

Contact Info

Product

Resources

About