臭氧吸收参数数据库精度检验和验证

CHECKING AND VALIDATING THE ABSORPTIONCOEFFICIENTS OF OZONE IN THE UV BAND

利用国际权威期刊上发表的臭氧吸收截面观测数据,检验和验证了现有的紫外正演模式TOMRAD臭氧吸收参数数据库。结果表明,在Hartley臭氧吸收带上,观测数据与数据库参数吻合状况很好;而在Huggins臭氧吸收带上,观测数据与数据库参数在部分波长上存在较大偏差,某些波长上的偏差超过50%。鉴于此,FY-3紫外臭氧探测仪资料处理计算中,选取臭氧吸收参数,必须特别慎重。

The knowledge of the absorption coefficients of ozone in the UV band is of major importance for the monitoring of the atmospheric ozone layer using the solar backscattering ultraviolet technique. In order to gain significant measurements of atmospheric ozone, accurate ozone absorption coefficients should be derived from the high accurate laboratory measurements of absorption cross-section of ozone. To make sure the absorption coefficients are be precise, it was checked and validated the now existing ozone coefficients bank in the American TOMRAD model using these high accurate and high resolution laboratory measurements data published in the international journals in the past few years. From 1980s, many papers on laboratory absorption cross of ozone measurement data with different spectrum resolution and measurement accuracy were published in all kinds of international journals. Among these, data from French Brion, et al. have much more higher spectrum resolution and measurement accuracy than others. First, some wavelengths were radnomly selected from Hartley and Huggins band respectively. For every wavelength, the regression model of the ozone absorption cross-section to temperature was built with the widely used polynomial formulas and the ozone absorption coefficients for these wavelengths were obtained. To check the now existing ozone absorption coefficients, the calculated coefficients were compared with that from the American TOMRAD model coefficient bank. Second, to validate the coefficients of the TOMRAD model, at these randomly selected wavelengths,the ozone absorption cross-section under the same temperature were calculated with that of Ozone UV Spectroscopy Ⅱ Absorption cross-sections and temperature dependence, and the calculated data were compared with the laboratory measurement data in Ozone UV Spectroscopy Ⅱ Absorption cross-sections and temperature dependence. The results show that the calculated cross-section at Hartley band using coefficients from the TOMRAD model is quite consistent with that laboratory measurement from Ozone UV Spectroscopy Ⅱ Absorption crosssections and temperature dependence, the variance at most randomly selected wavelengths is smaller than 3 %. However, in the Huggins band, the variance at most wavelengths is much more bigger, at some wavelengths, the variance is bigger than 50%. Since, data from Ozone UV Spectroscopy Ⅱ Absorption cross-sections and temperature dependence have higher spectrum resolution and accurate than that data by Bass and Paur, from which the now existing ozone absorption coefficients were drawn. It is reasons to suspect the validity of the now existing ozone absorption coefficients at some wavelength in Huggins band.