Elsevier

 Journal

 Comparing The Effect Of Trees On Thermal Conditions Of Two Typical Urban Buildings

 Tobi EnioluMorakinyo, Ahmed Adedoyin Baloguna, Olumuyiwa Bayode Adegun

 2005

An experimental investigation was carried out to determine the effect of trees on buildings' micro-climate. Parameters of thermal conditions were measured between September 2010 and February 2011 in and around two typical buildings located on a university campus. One of the buildings is shaded on the south eastern side by trees while the other is not. Indoor air temperature, outdoor air temperature and wall temperature were measured, while ancillary wind and solar radiation data were collected from the campus’ meteorological station. Comparisons on air temperature and wall temperature as measured inside and outside the shaded and un-shaded buildings were made. Air temperatures were higher and for longer hours throughout the study period inside the un-shaded building. Indoor–outdoor temperature differences show a peak of 5.4 °C for the un-shaded building while the tree-shaded did not exceed 2.4 °C. The results show that tree-shading constitutes an excellent passive cooling system for buildings, potentially enhances thermal control and conserves energy in buildings. 

 Taylor & Francis

 Journal

 Comparisons Of Urban And Rural Heat Stress Conditions In A Hot–humid Tropical City

 Ahmed A Balogun, Ifeoluwa A Balogun, Zachariah Debo Adeyewa

 2001

In recent years the developing world, much of which is located in the tropical countries, has seen dramatic growth of its urban population associated with serious degradation of environmental quality. Climate change is producing major impacts including increasing temperatures in these countries that are considered to be most vulnerable to the impact of climate change due to inadequate public health infrastructure and low income status. However, relevant information and data for informed decision making on human health and comfort are lacking in these countries. 

 Royal Meteorological Society

 Journal

 Predicting Monthly And Seasonal Rainfall, Onset And Cessation Of The Rainy Season In West Africa Using Only Surface Data

 J. Bayo Omotosho, A.A. Balogun And K. Ogunjobi

 2000

New empirical long?range schemes for the prediction of dates of onset and cessation and of the monthly and annual amounts of rainfall are developed for Kano, in the West African Sahel, using only surface synoptic data. They are based on variations in equivalent potential temperature, ?e, which occur as a result of the seasonal, monthly and daily variations of moisture in the summer monsoon flow over West Africa. Agricultural activities may begin about 72 days after the day the anomalies of ?e (i.e. ?') first become positive for at least 15 days, essentially signifying the beginning of adequate moisture supply associated with a well established monsoon flow. The new schemes ensure that both the cessation date and the annual amount of rainfall can be predicted prior to the onset of the rains, thus providing, in conjunction with the onset date, very important and useful information for reliable and effective planning of agricultural and water resource activities. Performance tests using an 11?year independent data set indicate that the schemes possess reliable skill. Because the weather over Nigeria is very typical of the entire West African region, being affected by the same wind regime and weather phenomena, these prediction schemes will provide tremendous assistance for enhanced and sustainable agriculture, as well as for efficient water resources management, if extended to the whole area. Furthermore, the methods have the important advantage that, bearing in mind the fact that the majority of West African countries have very sparse, if indeed, any upper?air data, the surface synoptic data needed for their use are readily available in all of the countries. 

 Springer

 Journal

 The Effect Of Atmospheric Stability On The Surface Layer Characteristics In A Low-wind Area Of Tropical West Africa

 Jegede, O.O., Fasheun, T.A., Adeyefa, Z.D., And Balogun, A.A.

 1997

This study details the observed effects ofatmospheric stability on characteristics of thesurface layer in a low wind speed (U = 1.5 m s-1)regime of tropical West Africa. Theaerodynamic roughness length, z0, anddisplacement height, d, obtained from profilewind-speed data at our bush land site (height ≈2 m)have values of 0.24 ± 0.10 m and 1.54 ± 0.04 mrespectively. In the unstable range (-2.5 < Ri < -0.1; Riis gradient Richardson number), thestandard deviation in wind speed fluctuations, σu, increased from 0.57 ± 0.19 m s-1 toa maximum of 0.7 ± 0.2 m s-1 in near-neutralconditions, and in the stable range, the parameterdecreased rapidly to 0.41 ± 0.15 m s-1 at Ri ≈ 0.2.In the same stability range, the horizontal winddispersion, σθ, decreased withincreasing stability from 19 ± 8 deg. to 13 ± 5 deg.The surface-layer integral quantity, σu/u*, when plottedas a function of stability, is in agreement with theempirical results. The ratio ofsensible heat flux (estimated) to the net radiationranged between 0.1 and 0.2 at nighttime,increasing to about 0.5 during the daytime, and showeda strong dependency on season.

 

 Kluwer Academic Publishers

 Journal

 The Effect Of Atmospheric Stability On The Surface-layer Characteristics In A Low-wind Area Of Tropical West Africa

 OO Jegede, TA Fasheun, ZD Adeyefa, AA Balogun

 1997

This study details the observed effects ofatmospheric stability on characteristics of thesurface layer in a low wind speed (U = 1.5 m s-1)regime of tropical West Africa. Theaerodynamic roughness length, z0, anddisplacement height, d, obtained from profilewind-speed data at our bush land site (height ?2 m)have values of 0.24 ± 0.10 m and 1.54 ± 0.04 mrespectively. In the unstable range (-2.5 < Ri < -0.1; Riis gradient Richardson number), thestandard deviation in wind speed fluctuations, ?u, increased from 0.57 ± 0.19 m s-1 toa maximum of 0.7 ± 0.2 m s-1 in near-neutralconditions, and in the stable range, the parameterdecreased rapidly to 0.41 ± 0.15 m s-1 at Ri ? 0.2.In the same stability range, the horizontal winddispersion, ??, decreased withincreasing stability from 19 ± 8 deg. to 13 ± 5 deg.The surface-layer integral quantity, ?u/u*, when plottedas a function of stability, is in agreement with theempirical results. The ratio ofsensible heat flux (estimated) to the net radiationranged between 0.1 and 0.2 at nighttime,increasing to about 0.5 during the daytime, and showeda strong dependency on season.