A small non-research vessel as a platform for lake surface flux measurements

Abstract The flux of water vapor due to advection is measured using high-resolution Raman lidar that was orientated horizontally across a land–lake transition. At the same time, a full surface energy balance is performed to assess the impact of scalar advection on energy budget closure. The flux of water vapor due to advection is then estimated with analytical solutions to the humidity transport equation that show excellent agreement with the field measurements. Although the magnitude of the advection was not sufficient to account for the total energy deficit for this field site, the analytical approach is used to explore situations where advection would be the dominant transport mechanism. The authors find that advection is at maximum when the measurement height is 0.036 times the distance to a land surface transition. The framework proposed in this paper can be used to predict the potential impact of advection on surface flux measurements prior to field deployment and can be used as a data analysis algorithm to calculate the flux of water vapor due to advection from field measurements.

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Novel meteorological methods for measuring trace gas fluxes

Philosophical Transactions of the Royal Society of London Series A Physical and Engineering Sciences ◽

10.1098/rsta.1995.0041 ◽

1995 ◽

Vol 351 (1696) ◽

pp. 383-396 ◽

Cited By ~ 51

Keyword(s):

Diffusion Theory ◽

Animal Experiments ◽

Surface Flux ◽

Test Plot ◽

Plant Canopies ◽

Gradient Diffusion ◽

Gas Fluxes ◽

Trace Gas Fluxes ◽

Flux Measurements ◽

Source Sink

The paper deals with flux measurements in two contexts: small plots and plant canopies. Mass balance methods have been developed for small experimental plots with lateral dimensions of tens of metres rather than the 1 m typical of chambers or the hundreds of metres required for conventional micrometeorological estimates. The general method relies on the conservation of mass to equate the differences in horizontal fluxes across upwind and downwind boundaries of a test plot with the surface flux within the plot along the line of the wind. Applications to soil and animal experiments are discussed. Lagrangian descriptions of transport now supplant older, but inappropriate gradient-diffusion theory for inferring fluxes and source-sink distributions of scalars in plant canopies. An inverse Lagrangian theory due to M. R. Raupach provides a relatively simple observational and computational scheme for making such inferences from measurements of mean concentration profiles and canopy turbulence. The scheme and a range of applications are described.

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Surface Flux Measurements at King Sejong Station in West Antarctica: I. Turbulent Characteristics and Sensible Beat Flux

Ocean and Polar Research ◽

10.4217/opr.2004.26.3.453 ◽

2004 ◽

Vol 26 (3) ◽

pp. 453-463 ◽

Cited By ~ 3

Author(s):

Tae-Jin Choi ◽

Bang-Yong Lee ◽

Hee-Choon Lee ◽

Jae-Seol Shim

Keyword(s):

Surface Flux ◽

West Antarctica ◽

Turbulent Characteristics ◽

Flux Measurements

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Workshop on Instrumental and Methodical Problems of Land Surface Flux Measurements

Bulletin of the American Meteorological Society ◽

10.1175/1520-0477-76.7.1191 ◽

1995 ◽

Vol 76 (7) ◽

pp. 1191-1224 ◽

Cited By ~ 61

Author(s):

Thomas Foken ◽

Steven Oncley

Keyword(s):

Energy Balance ◽

Land Surface ◽

Additional Data ◽

State Of The Art ◽

Surface Flux ◽

The State ◽

General Assembly ◽

Atmospheric Physics ◽

Atmospheric Research ◽

Flux Measurements

This report summarizes presentations and discussions that occurred at a workshop held in conjunction with the XIXth General Assembly of the European Geophysical Society (EGS) from 22 to 24 April 1994. The purpose of this workshop was to define the state of the art of micrometeorological flux measurements, to identify problem areas, and to define any additional data that must be taken to solve these problems. This workshop was organized in response to a proposal made at the 1993 EGS conference by T. Foken, T. Delany (National Center for Atmospheric Research), S. Oncley, and L. Tsvang (Institute of Atmospheric Physics, Russia) for a new experiment to investigate the problem of the “unclosed” energy balance. Sixty-one scientists from 14 countries participated in the workshop.

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