کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6337042 1620349 2015 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Influences of extinction coefficient profile on the estimation of Slant Visual Range
ترجمه فارسی عنوان
تأثیر ضریب انقباض مشخصات بر روی برآورد محدوده بصری اسلات
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات علم هواشناسی
چکیده انگلیسی
Slant Visual Range (SVR) is defined as the distance at which the contrast of a given object with respect to its background is just equal to the contrast threshold of an observer in slant direction. In this study, estimation methods and errors of SVR are explored in lidar-free circumstances where Extinction Coefficient Profile (ECP), vertical distribution of Single Scattering Albedo (SSA) and asymmetry parameter (ASY) cannot be acquired. Statistical characteristics of aerosol optical properties in the Taklimakan Basin for sand-dust weather are derived from the CALIPSO daytime aerosol product from 2011 to 2014. SSA and ASY are approximated as 0.92 and 0.7 because aerosol types are mainly dust and polluted dust throughout layers. Besides, ECP can be categorized into exponential, Gaussian and other patterns. Based on whether the determination of real ECP into one of the three patterns is feasible, two SVR estimation methods are introduced and termed the accurate estimation method (AEM) and the blind estimation method (BEM), both methods are performed using SBDART radiative transfer model. For the AEM, analysis of estimated SVR and real SVR reveals a minimum linear correlation coefficient of 0.98 and a maximum root mean square error of 0.07, and the hit rate (R) of SVR estimation increases from 86% to nearly 100% when the maximum allowable relative error (MARE) increases from 10% to 25%. Validation of the BEM shows that R varies from 78% to 100% for MARE of 25% and falls drastically with the decrease of MARE, with the highest R value in spring and summer for the Gaussian pattern and the lowest values in fall and winter for exponential and other patterns. This study is among the first to explore the feasibility and methodology of deriving SVR in lidar-free circumstances.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Atmospheric Environment - Volume 122, December 2015, Pages 484-492
نویسندگان
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