Focusing on the important role of ground-based sun radiation and aerosol observation in the fields of climate change

atmospheric environmental monitoring

and earth observation

we established a Sun-sky radiometer Observation NETwork（ SONET） in typical Chinese regions by applying multi-wavelength polarimetric observation techniques. We present the following in this paper:（ 1） the characteristics

measurement

principles

and functions of the multi-wavelength polarization radiometer and the establishment of SONET in typical Chinese regions with a brief introduction of the observation sites;（ 2） observation patterns of sun-sky radiation and polarization as well as measurement parameters under direct sun

solar principal plane

and almucantar geometries;（ 3） calibration of solar irradiance

sky radiance

and degree of linear polarization measurements and data processing methods for aerosol and water vapor

with illustrations of typical SONET observation under clear and hazy conditions;（ 4） establishment of urban

rural

and haze aerosol type models of the total column atmosphere based on long-term continuous remote sensing observation in typical sites in China. On the basis of extension of multi-wavelength polarization measurements

SONET was employed to develop operational techniques for the network of sun-sky radiometers

including automatic observation

fast data processing

and regular calibration and maintenance

which contribute to the construction of atmospheric aerosol type models

retrieval and validation of satellite aerosol products

and remote monitoring of the atmospheric environment.