Determination of Heat and Momentum Fluxes Over Baghdad City

Mustafa Zihraw Mehson, Ahmed Fattah Hassoon

Abstract


In this study heat and momentum fluxes have been determined at Al-Mustansiriyah University, Baghdad, Iraq, by using eddy correlation method. It is one of the methods which determines heat and momentum fluxes and it is considered direct and accurate. This method depends on high response instruments like Ultrasonic Anemometer (model: 1590- PK- 020) which is used in this study. Observation period is about 53 days for 24 hours in months June, July and August from 15/06/2016 to 06//08/2016 and the observations included wind speed and temperature every second. MATLAB program has been used to process huge data to calculate heat and momentum fluxes (H and ). The maximum value of H equals 127.6 Wm-2 in 10:30 at 26/07/2016 and minimum value equals -58.9 Wm-2 in 07:30 at 29/06/2016, as well, the maximum value of  equals 0.134535 Nm-2 in 15:00 at 03/08/2016 and minimum value equals -0.4649 Nm-2 in 03:00 at 01/07/2016. It is found that there is an inverse relationship between H and. Also maximum frequency of friction velocity at unstable conditions.

Keywords


Momentum flux, Heat flux, Obukhov length, Stability.

Full Text:

PDF

References


Jegede O. O. and P. Lofstrom, "Fluxes of sensible heat flux and momentum in surface layer estimated from the profile measurements of wind and temperature at a tropical station", ATMOSFERA, Vol. 10, pp. 213-223, 1997.

Hsieh C. I., G. G. Katul, J. T. Sigmon and K. R. Knoerr, "Estimation of momentum and heat fluxes using dissipation and flux-variance methods in the unstable surface layer", Water Resources Research, Vol. 32, pp. 2453–2462, 1996.

User Manual, Wind Master (Part 1590-PK-020) & Wind Master Pro (Part 1561-PK-020), Ultrasonic Anemometer, Doc No. 1561-PS-0001, Issue 07, 2011.

Stull Roland B., "An Introduction to Boundary Layer Meteorology", Kluwer Academic Publishers, 670 pp., 1988.

Foken Thomas, "Micrometeorology", Springer, Berlin, 308 pp., 2008.

Arya S. P., "Introduction to Micrometeorology", Second edition, Vol. 79, Academic press, 420 pp, 2001.

Hutschemaekerrs J. J. W., "Comparison of classification systems to define Atmospheric Stability and their impact on Wind Turbine Design", M.Sc. Thesis, Faculty of Aerospace Engineering & Applied Physics, Delft University of Technology, 2014.

Sjo ̈blom A., "Turbulent fluxes of momentum and heat over land in the High-Arctic Summer: the influence of observation techniques", Citation: Polar Research, Vol. 33, 2014.

Sathe A., "Project Site Data - OWEZ data analysis", Delft University of Technology, Delft, p. 52, 2010.

Lee X., W. Massman and B. Law, editors, "Handbook of Micrometeorology: A guide for Surface Flux Measurements and Analysis", Volume 29 of Atmospheric and Oceanographic Sciences Library, Kluwer Academic Publishers, Dordrecht, 2005.

Novick K. A., J. Walker, W. S. Chan, A. Schmidt, C. Sobek and J. M. Vose, "Eddy covariance measurements with a new fast-response, enclosed-path analyzer: Spectral characteristics and cross-system comparisons", Agricultural and Forest Meteorology, Vol. 181, pp. 17-32, 2013.

Bottema M., "Aerodynamic roughness parameters for homogeneous building groups- part 2: Results. Document SUB-MESO#23", Ecole Centrale de Nantes, France, 1995.

Holtslag A. A. M., "Estimates of diabatic wind speed profiles from near-surface weather observations", Boundary Layer Meteorology, Vol. 29, pp. 225-250, 1984.

Romi T. A., "Estimation of the vertical distribution of wind speed and temperature within the lowest 100m above Baghdad", M.Sc. Thesis, College of Sciences, Al-Mustansiriyah University, Baghdad, Iraq, 2000.

Monin A. S. and A. M. Obukhov, "Osnovnye zakonomernosti turbulentnogo peremesivanija v prizemnom sloe atmosfery (Basic laws of turbulent mixing in the atmosphere near the ground)", Trudy geofiz inst AN SSSR 24 (151), pp. 163–187, 1954.

Panofsky H. A. and J. A. Dutton, "Atmospheric Turbulence: Models and Methods for Engineering Applications", New York, 389 pp., 1984.




DOI: http://dx.doi.org/10.23851/mjs.v30i1.146

Refbacks

  • There are currently no refbacks.


Copyright (c) 2019 Al-Mustansiriyah Journal of Science

Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.


Copyright (c) 2018 by Al-Mustansiriyah Journal of Science
ISSN: 1814-635X (Print), ISSN: 2521-3520 (online)