A new method for determining the Angstrom turbidity coefficient from broadband filter measurements

In this work, a new method for determining Angstrom turbidity coefficients is presented. This method is based on broadband filter irradiance measureme nts. By combining measurements obtained with different filters it is possib le to obtain a single value of the turbidity coefficient representative of the whole measurement range of the pyrheliometer. The results provided by t his new method are compared with the original Angstrom method and turbidity coefficient values derived by spectroradiometric measurements. The results reproduce the actual values, as measured by a spectroradiometer, better th an the previous best correlation did, thus demonstrating the advantage of a nalyzing the optical thickness from bands covering the whole spectral range .