Multi-angular thermal infrared emission characteristics of Bohai Sea ice based on in situ measurements

Abstract

ABSTRACT. We report on the radiative transfer process and optical properties of sea ice in the thermal infrared (TIR) band, presenting two new linear kernel driver models (Relative Emissivity Distribution Function, REDF) that describe TIR emission characteristics of smooth and rough ice. In order to test the models and determine the necessary coefficients, in situ measurements from the Bohai Sea were carried out during the 2011/12 and 2012/13 boreal winters. The results show that the relative emissivity of smooth sea ice decreases along with increasing viewing zenith angle, and the shape of the relative emissivity curve is similar to that of an ideal plane. Affected by parameters such as roughness and surface temperature distribution, the anisotropy of relative emissivity of sea ice with a high degree of roughness is stronger relative to the cosine emitter. The model coefficients were also obtained using a robust regression method based on the measured data. The presented models are more practical than the numerical radiative transfer model and can be used for multi-angular TIR remote sensing.

Practical Model of Sea Ice Thickness of Bohai Sea Based on MODIS Data

“…Sea ice in winter is a major potential threat to production activities, coastal traffic safety, marine farming, and offshore oil platforms in the Bohai Sea (Li et al, 2004;Gu et al, 2013). According to the ongoing study results of sea ice desalination by Chinese researchers, it is possible to convert sea ice (brackish water) into fresh water by desalination to provide a new freshwater resource for the coastal areas of the Bohai Sea (Gu et al, 2012;Chao et al, 2015). The data of sea ice area, thickness and other parameters are important in the sea ice engineering design, sea ice disaster prevention and mitigation, and the utilization of sea ice resources in the Bohai Sea (Guo et al, 2008;Liu et al, 2013).…”

“…Optical remote sensing images (Xie et al, 2003;Luo et al, 2004;Wu et al, 2006;Ning et al, 2009;Su and Wang, 2012;Yuan et al, 2012;2017;Liu et al, 2016), thermal infrared remote sensing images (Wu et al, 2005;Chao et al, 2015), and microwave remote sensing images (Zhang, 2011;Zhang et al, 2013; have been widely used in the estimation of sea ice area and thickness in the Bohai Sea, especially for the optical remote sensing. The main reasons may be described as follows.…”