【英文】A new more accurate description of ……

Cirrus clouds play an important role in the Earth’s radiation budget, they absorb long-wave outgoing radiation from Earth surface and reflect incoming solar radiation. So, Cirrus clouds are of vital significance to Earth's climate system. 

Recently, Dr. WANG Zhenzhu with his colleagues from the center of atmosphere optics in Anhui Institute of Optics and Fine Mechanics (AIOF M) and Prof. Anatoli Borovoi with his group from Institute of Atmospheric Optics (IAO) has made new improvement on theory of extinction matrix for cirrus clouds under international co-operation.

The extinction matrixes as the functions of the incident wavelength, incident direction, crystal size, and crystal orientation are numerically calculated for the first time. It is shown that the off-diagonal elements of the matrix are negligible. Therefore, the extinction in cirrus clouds is described with good accuracy by the scalar exponential law. The research could contribute to a more accurate analysis of Earth's climate system.

The results was published in OPTICS LETTERS. This work is funded by National Natural Science Foundation of China (NSFC) (41811530088), Chinese Academy of Sciences (CAS) President’s International Fellowship Initiative (PIFI) (2016VEA044), Youth Innovation Promotion Association of CAS (2017482) and Bureau of International Cooperation, CAS.

More information will be found in https://doi.org/10.1364/OL.43.003578

Figure 1. Extinction correction for the normal incidence on the ensemble of horizontally oriented crystals when μ = 1

(Image by WANG Zhenzhu)

Figure 2. Extinction correction for the oblique incidence θ = 30^o on the ensemble of horizontally oriented crystals

 (Image by WANG Zhenzhu)