Abstract:
In this research work, assessments of the extent and spatial-temporal trends of outdoor bioclimatic
conditions in five selected Local Government Areas (LGAs) of Ondo state, Nigeria were executed.
The data used for this research work comprises air temperature, vapor pressure, wind speed and
cloud cover which were obtained from the archive of Climate Research Unit (CRU). The data span
through 1983 to 2012.
Bioclimatic indices of different sensitivities were utilized. Temperature Humidity Index (THI) and
Relative Strain Index (RSI) are the non-thermo-physiologically sensitive indices used while
Physiologically Equivalent Temperature (PET) and Predicted Mean Vote (PMV) are the thermophysiologically
sensitive ones. Radiation and human bioclimate (RayMan) model was used to
compute the thermo-physiologically sensitive indices (PET and PMV).
Thermal conditions had increasing trend patterns and they deteriorated the more as the years
progressed such that there were more defined levels of deterioration in comfort conditions at all
LGAs within the last decade than there were in the first two decades. Three epochs of thermal
conditions occurred in 1987, 1998 and 2010. Ondo State was characterized by cold stress, comfort
and heat stress conditions. The southern parts of the state were more comfortable than the northern
parts of the state. Thermal conditions were found to be more tolerable in wet season and less
tolerable in dry season. In addition, air temperature was discovered to be the meteorological
parameter that has highest percentage contribution to thermal conditions. The results of this
research work can be helpful in making heat forecasting more meaningful to the general public,
emergency responders and urban planners. Also, the results can help those performing physical
activities outdoors to know when optimum performance can be achieved.
