ESTIMATING BLACK GLOBE TEMPERATURE FROM THE DRY BULB TEMPERATURE

Abstract

One disadvantage of bioclimatic diagnosis in certain region is non-availability of black globe temperatures (BGT) in the meteorological stations situated in different parts of the country. This study was done to propose a equation to estimate BGT from the dry bulb temperature (DBT), in confined and outdoors systems. Data of BGT and DBT were collected from inside and outside poultry sheds and analyzed using regression models to predict BGT from DBT data. A total of 5664 and 337 temperature readings were obtained from inside and outside poultry house, respectively. A statistical analysis was done with the use of statistical software R. A strong correlation was found between BGT and DBT. It was concluded that in chickens sheds with DBT between 0 and 35oC, BGT can be estimated using DBT readings. Adjusted linear regression model had R² of 0.9788 with correlation coefficient of 0.9893. The relationship was not so evident for temperatures outside the measured readings, due to strong effect of the solar radiation on black globe thermometer. It is possible to estimate BGT from DBT readings obtained from internal or external environment.