In the study Ts was derived from band 6 TIR of Landsat TM5 using the model developed by Sobrino et al. in 2004:Ts=TB1+(��?TB/r)ln(?)(5)where �� is the wavelength of emitted radiance (��=11.5), r=h?c?�� equalling 1.438 10-2 mK, where h is Planck’s constant (6.626 10-34 J s), c the velocity of light (2.998 108 m s-1) and �� the Boltzman constant (1.38 10-23 JK-1); emissivity �� was estimated through [28]:?=fv?v+(1?fv)??s(6)where ��v and ��s denote emissivity of vegetation (0.985) and soil (0.960). The fractional vegetation cover fv is related to leaf area index (LAI), fv = 1 ? e?0.5?LAI [9]. By applying the inverse of Plank’s radiation equation, spectral radiance in the thermal band was converted to brightness temperature TB:TB=K2ln(K1L��+1)(7)where K1 and K2 are calibration constants (equal to 607.

76 W m-2 sr-1 ��m-1 and 1260.56 K respectively) defined for Landsat 5 TM sensor [29]; L�� is the pixel value as radiance (W m-2 sr-1 ��m-1), L��=G?(CVDN)+B, with CVDN the pixel value as digital number, G and B the gain and the
The correction of atmospheric path delays in high-resolution spaceborne synthetic aperture radar systems has become increasingly important with continuing improvements to the resolution of SAR systems surveying the Earth. Atmospheric path delays must be taken into account in order to achieve geolocation accuracies better than 1 meter. These effects are mainly due to ionospheric and tropospheric influences. Path delays through the ionosphere are frequency-dependent, proportional to the inverse square of the carrier [1, 2].

At frequencies higher than L-band under average solar conditions, the major contribution of the atmospheric path delay comes from the troposphere [2, 3]. The tropospheric delay is usually divided into hydrostatic, wet and liquid components [4]. The hydrostatic delay is mainly related to the dependency of the refractive index on the air pressure (i.e. target altitude) and the wet delay on the water vapour pressure. The liquid delay is due to clouds and water droplets. While the wet component can be highly variable, the hydrostatic delay normally only changes marginally because of the lack of significant pressure variations within the extent of a typical SAR scene [4].Interferometric radar meteorology produces high resolution maps of integrated water vapour for investigations in atmospheric dynamics and forecasting [4].

Using that knowledge, global and local atmospheric effects (e.g. vortex streets, heterogeneities, turbulences) can be detected or even removed using interferometric and multi-temporal data [5�C7], or by inclusion of global water Anacetrapib vapour maps from the ENVISAT Medium Resolution Imaging Spectrometer (MERIS) sensor [8]. In addition to interferometric applications, there is a growing interest in the correction of atmospheric influences within a single SAR image.