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

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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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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Long-Term Observations and High-Resolution Modeling of Midlatitude Nocturnal Boundary Layer Processes Connected to Low-Level Jets

Journal of Applied Meteorology and Climatology ◽

10.1175/jamc-d-17-0341.1 ◽

2018 ◽

Vol 57 (5) ◽

pp. 1155-1170 ◽

Cited By ~ 10

Author(s):

Tobias Marke ◽

Susanne Crewell ◽

Vera Schemann ◽

Jan H. Schween ◽

Minttu Tuononen

Keyword(s):

High Resolution ◽

Surface Flux ◽

Turbine Rotor ◽

Surface Fluxes ◽

Open Pit ◽

Intermittent Turbulence ◽

Low Level ◽

Energy Applications ◽

Turbulent Characteristics

AbstractLow-level-jet (LLJ) periods are investigated by exploiting a long-term record of ground-based remote sensing Doppler wind lidar measurements supported by tower observations and surface flux measurements at the Jülich Observatory for Cloud Evolution (JOYCE), a midlatitude site in western Germany. LLJs were found 13% of the time during continuous observations over more than 4 yr. The climatological behavior of the LLJs shows a prevailing nighttime appearance of the jets, with a median height of 375 m and a median wind speed of 8.8 m s−1 at the jet nose. Significant turbulence below the jet nose only occurs for high bulk wind shear, which is an important parameter for describing the turbulent characteristics of the jets. The numerous LLJs (16% of all jets) in the range of wind-turbine rotor heights below 200 m demonstrate the importance of LLJs and the associated intermittent turbulence for wind-energy applications. Also, a decrease in surface fluxes and an accumulation of carbon dioxide are observed if LLJs are present. A comprehensive analysis of an LLJ case shows the influence of the surrounding topography, dominated by an open pit mine and a 200-m-high hill, on the wind observed at JOYCE. High-resolution large-eddy simulations that complement the observations show that the spatial distribution of the wind field exhibits variations connected with the orographic flow depending on the wind direction, causing high variability in the long-term measurements of the vertical velocity.

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