AN INVESTIGATION OF PHOTOSYNTHETICALLY ACTIVE RADIATION AT PHRANAKHON RATJABHAT UNIVERSITY, THAILAND
Keywords:
Photosynthetically active radiation, measurement, Phranakhon Rajabhat UniversityAbstract
In this work, Photosynthetically active radiation (PAR) was measured at Phranakhon Rajabhat University (13.88°N 100.59°E), Bangkok Thailand. A one year period (2017) of the measurement data was analyzed. The diurnal and seasonal variation of photosynthetically active radiation were investigated. The diurnal pattern shows the maximum values of PAR at local noon time with the highest peak value in March. For the seasonal variation, the monthly average of PAR shows the higher values during the summer and the lower values during the winter. The PAR values ranged from 26.73 mol/m2 in January to the highest of 37.02 mol/m2 in April and the annual mean value is 31.34 mol/m2. Based on measurement data, the model for estimating photosynthetically active radiation from broadband solar radiation was also proposed.
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