Correlation between cloud optical thickness and solar radiation

In this paper, the correlation between cloud optical thickness and solar radiation is investigated. The clear-sky solar radiation model for Singapore region is applied to find the decrease of solar radiation (difference between the measured solar radiation and clear-sky solar radiation model). Four-month cloud optical thickness and solar radiation data located at Nanyang Technological University (NTU) are processed. The results show that the cloud optical thickness has a roughly exponential relationship with the decrease of solar radiation.