کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
8866474 | 1621185 | 2018 | 13 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
The influence of snow microstructure on dual-frequency radar measurements in a tundra environment
ترجمه فارسی عنوان
تأثیر ریز ساختار برف بر روی اندازه گیری رادار دو فریم در یک محیط تاندرا
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
موضوعات مرتبط
مهندسی و علوم پایه
علوم زمین و سیارات
کامپیوتر در علوم زمین
چکیده انگلیسی
Recent advancement in the understanding of snow-microwave interactions has helped to isolate the considerable potential for radar-based retrieval of snow water equivalent (SWE). There are however, few datasets available to address spatial uncertainties, such as the influence of snow microstructure, at scales relevant to space-borne application. In this study we introduce measurements from SnowSAR, an airborne, dual-frequency (9.6 and 17.2â¯GHz) synthetic aperture radar (SAR), to evaluate high resolution (10â¯m) backscatter within a snow-covered tundra basin. Coincident in situ surveys at two sites characterize a generally thin snowpack (50â¯cm) interspersed with deeper drift features. Structure of the snowpack is found to be predominantly wind slab (65%) with smaller proportions of depth hoar underlain (35%). Objective estimates of snow microstructure (exponential correlation length; lex), show the slab layers to be 2.8 times smaller than the basal depth hoar. In situ measurements are used to parametrize the Microwave Emission Model of Layered Snowpacks (MEMLS3&a) and compare against collocated SnowSAR backscatter. The evaluation shows a scaling factor (Ï) between 1.37 and 1.08, when applied to input of lex, minimizes MEMLS root mean squared error to <1.1â¯dB. Model sensitivity experiments demonstrate contrasting contributions from wind slab and depth hoar components, where wind rounded microstructures are identified as a strong control on observed backscatter. Weak sensitivity of SnowSAR to spatial variations in SWE is explained by the smaller contributing microstructures of the wind slab.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Remote Sensing of Environment - Volume 215, 15 September 2018, Pages 242-254
Journal: Remote Sensing of Environment - Volume 215, 15 September 2018, Pages 242-254
نویسندگان
Joshua King, Chris Derksen, Peter Toose, Alexandre Langlois, Chris Larsen, Juha Lemmetyinen, Phil Marsh, Benoit Montpetit, Alexandre Roy, Nick Rutter, Matthew Sturm,