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21 results on '"Clement, Robert J."'

2. Mass and energy exchange of a plantation forest in Scotland using micrometeorological methods

Author

Clement, Robert J.

Subjects
551.5
Abstract

This thesis presents the energy, water, and carbon budgets of Sitka spruce plantation forest in Scotland over the period 1997 to 2001. The site microclimate is observed to be strongly influenced by the site’s oceanic climate, and canopy development. Atmospheric structure is observed to affect temporal patterns of microclimatological variables while topography is observed to affect microclimatological and flux measurements. Eddy covariance flux measurement theory and methods are examined and specific inadequacies are addressed. Theoretical aspects of eddy covariance that were examined include signal despiking, coordinate rotation, low frequency contributions, as well as correlations for density fluctuations, angle of attack errors, and sonic temperature determination. An analysis of frequency response correction methods was used to determined if superior methods could be identified. Fluxes of momentum were used to verify existing measures of atmospheric turbulence and analysed to identify canopy structure and growth. Sensible heat fluxes were found to have an unexpected negative bias, only a portion of which can be attributed to instrument error. This bias is found to depend upon topography and wind speed but is apparently unrelated to katabatic flow. Large errors in latent heat flux were caused by enhanced tube attenuation and were corrected using improved frequency response corrections. Interannual variability of momentum and sensible heat flux were closely associated with wind speed variability, while interannual variability of NEE was attributable primarily to radiation. The source of variability of latent heat flux was not clearly identifiable. Missing values of latent heat flux were modelled using a canopy conductance model, which incorporated effects of canopy evaporation.

Published
2004

6. Momentum, water vapor, and carbon dioxide exchange at a centrally located prairie site during FIFE

Author

Verma, Shashi B, Kim, Joon, and Clement, Robert J

Subjects
Meteorology And Climatology
Abstract

Eddy correlation measurements were taken of momentum, water vapor, sensible heat, and CO2 at a centrally located plateau site in the FIFE study area from May to October 1987. Approximately 82 percent of the vegetation at the site was composed of several C4 grass species, with the remainder being C3 grasses, forbs, wedges, and woody plants. Precipitation was about normal during the study period, except for a three week dry period in late July to early August that caused moisture stress conditions.

Published
1992

7. Carbon dioxide budget in a temperature grassland ecosystem

Author

Kim, Joon, Verma, Shashi B, and Clement, Robert J

Subjects
Geophysics
Abstract

Eddy correlation measurements of CO2 flux made during May-October 1987 and June-August 1989 were employed, in conjunction with simulated data, to examine the net exchange of CO2 in a temperature grassland ecosystem. Simulated estimates of CO2 uptake were used when flux measurements were not available. These estimates were based on daily intercepted photosynthetically active radiation, air temperature, and extractable soil water. Soil CO2 flux and dark respiration of the aerial part of plants were estimated using the relationships developed by Norman et al. (1992) and Polley et al. (1992) at the study site. The results indicate that the CO2 exchange between this ecosystem and the atmosphere is highly variable. The net ecosystem CO2 exchange reached its peak value (12-18 g/sq m d) during the period when the leaf area index was maximum. Drought, a frequent occurrence in this region, can change this ecosystem from a sink to a source for atmospheric CO2. Comparison with data on dry matter indicated that the aboveground biomass accounted for about 45-70 percent of the net carbon uptake, suggesting the importance of the below ground biomass in estimating net primary productivity in this ecosystem.

Published
1992

8. Job Satisfaction of Financial Aid Administrators in Illinois.

Author

Clement, Robert J. and White, Gordon W.

Abstract

A survey of financial aid administrators in Illinois studied the possible relationships of institutional type, job title, and years of experience on administrators' personal security, socialization, self-esteem, autonomy, self-actualization, and feeling of being knowledgeable. (MSE)

Published
1983

9. Nicholls Teacher Education Program.

Author

Nicholls State Univ., Thibodaux, LA. and Clement, Robert J.

Abstract

A teacher education course strongly emphasizing field work in classrooms, team teaching, and providing early opportunity for informed career choice is described. The following major objectives of the course are identified and their implementation described: (1) provide students with intensified field experiences very early in and throughout the teacher education program; (2) provide for more effective utilization of faculty through teaching teams; (3) provide for more program flexibility by using block scheduling of professional courses; (4) provide for early identification and counseling of prospective teachers; and (5) enhance individualization of instruction through the development and utilization of a learning resource center. (JD)

Published
1978

12. Quantifying landscape‐level methane fluxes in subarctic Finland using a multiscale approach

Author

Hartley, Iain. P., primary, Hill, Timothy. C., additional, Wade, Thomas. J., additional, Clement, Robert. J., additional, Moncrieff, John. B., additional, Prieto‐Blanco, Ana., additional, Disney, Mathias. I., additional, Huntley, Brian., additional, Williams, Mathew., additional, Howden, Nicholas. J. K., additional, Wookey, Philip. A., additional, and Baxter, Robert., additional

Published
2015
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13. Quality control of CarboEurope flux data - Part I: Footprint analyses to evaluate sites in forest ecosystems

Author

Göckede, Mathias, Foken, Thomas, Aubinet, Marc, Aurela, Mika, Banza, João, Bernhofer, Christian, Bonnefond, Jean Marc, Brunet, Yves, Carrara, Arnaud, Clement, Robert J., Dellwik, Ebba, Elbers, Jan A., Eugster, Werner, Fuhrer, Jürg, Granier, André, Grünwald, Thomas, Heinesch, Bernhard, Janssens, Ivan A., Knohl, Alexander, Koeble, Renate, Laurila, Tuomas, Longdoz, Bernard, Manca, Giovanni, Marek, Michal V., Markkanen, Tiina, Matteucci, Giorgio, Mauder, Matthias, Migliavacca, Mirco, Minerbi, Stefano, Moncrieff, John B., Montagnani, Leonardo, Moors, Eddy J., Ourcival, Jean-Marc, Papale, Dario, Pereira, João Santos, Pilegaard, Kim I.M., Pita, Gabriel P.A., Rambal, Serge, Rebmann, Corinna, Rodrigues, Abel D., Rotenberg, Eyal, Sanz-Sanchez, Maria José, Sedlák, Pavel, Seufert, Günther, Soussana, Jean-François, Valentini, Riccardo, Vesala, Timo, Verbeeck, Hans, and Yakir, Dan

Abstract

We applied a site evaluation approach combining Lagrangian Stochastic footprint modelling 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. ISSN:1810-6277 ISSN:1810-6285

Published
2007

15. How to build and maintain master files

Author

Clement, Robert J.

Subjects
Pharmacy management -- Methods, Computers -- Usage, Filing systems -- Planning, Pharmacists -- Records and correspondence, Business, Health care industry, Pharmaceuticals and cosmetics industries, Retail industry
Published
1985

16. Quality control of CarboEurope flux data - Part I: Footprint analyses to evaluate sites in forest ecosystems

Author

Göckede, Mathias, Foken, Thomas, Aubinet, Marc, Aurela, Mika, Banza, João, Bernhofer, Christian, Bonnefond, Jean Marc, Brunet, Yves, Carrara, Arnaud, Clement, Robert J., Dellwik, Ebba, Elbers, Jan A., Eugster, Werner, Fuhrer, Jürg, Granier, André, Grünwald, Thomas, Heinesch, Bernhard, Janssens, Ivan A., Knohl, Alexander, Koeble, Renate, Laurila, Tuomas, Longdoz, Bernard, Manca, Giovanni, Marek, Michal V., Markkanen, Tiina, Matteucci, Giorgio, Mauder, Matthias, Migliavacca, Mirco, Minerbi, Stefano, Moncrieff, John B., Montagnani, Leonardo, Moors, Eddy J., Ourcival, Jean-Marc, Papale, Dario, Pereira, João Santos, Pilegaard, Kim I.M., Pita, Gabriel P.A., Rambal, Serge, Rebmann, Corinna, Rodrigues, Abel D., Rotenberg, Eyal, Sanz-Sanchez, Maria José, Sedlák, Pavel, Seufert, Günther, Soussana, Jean-François, Valentini, Riccardo, Vesala, Timo, Verbeeck, Hans, and Yakir, Dan

Subjects
13. Climate action, 15. Life on land
Abstract

We applied a site evaluation approach combining Lagrangian Stochastic footprint modelling 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., Biogeosciences Discussions, 4 (6), ISSN:1810-6277, ISSN:1810-6285

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

Author

Göckede, Mathias, Foken, Thomas, Aubinet, Marc, Aurela, Mika, Banza, João, Bernhofer, Christian, Bonnefond, Jean Marc, Brunet, Yves, Carrara, Arnaud, Clement, Robert J., Dellwik, Ebba, Elbers, Jan A., Eugster, Werner, Fuhrer, Jürg, Granier, André, Grünwald, Thomas, Heinesch, Bernhard, Janssens, Ivan A., Knohl, Alexander, Koeble, Renate, Laurila, Tuomas, Longdoz, Bernard, Manca, Giovanni, Marek, Michal V., Markkanen, Tiina, Mateus, João A., Matteucci, Giorgio, Mauder, Matthias, Migliavacca, Mirco, Minerbi, Stefano, Moncrieff, John B., Montagnani, Leonardo, Moors, Eddy J., Ourcival, Jean-Marc, Papale, Dario, Pereira, João Santos, Pilegaard, Kim, Pita, Gabriel P.A., Rambal, Serge, Rebmann, Corinna, Rodrigues, Abel, Rotenberg, Eyal, Sanz-Sanchez, Maria José, Sedlák, Pavel, Seufert, Günther, Siebicke, Lukas, Soussana, Jean-François, Valentini, Riccardo, Vesala, Timo, Verbeeck, Hans, and Yakir, Dan

Subjects
13. Climate action, 15. Life on land
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., Biogeosciences, 5 (2), ISSN:1726-4170

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