Physical modeling of passive polarimetric microwave observations of the atmosphere with respect to the third Stokes parameter

Abstract

Abstract. Measurements of upwelling and downwelling rain brightness temperatures show significant differences between horizontal and vertical polarization, which depend on wavelength and rain rate. These measurements are related to the first and second Stokes parameter. Also, the third Stokes parameter of atmospheric microwave emission will have measurable values under certain conditions. A polarimetric model for the description of the microwave emission and scattering by hydrometeors, including all four Stokes parameters, is presented. This model is applied to the scenario of plane layers of ice crystals and rain above a rough surface. The magnitudes of the third Stokes parameter for microwave emission from oriented nonspherical rain drops and for scattering by ice crystals are estimated. It is shown that the third Stokes parameter for rain is dominated by the first azimuthal harmonic of the emission vector. Finally, an algorithm for the computation of polarized brightness temperatures emanating from cylindrical rain cells above a surface is developed.

Polarization of Atmospheric Millimeter Radiation in the Process of Precipitation Observed from Space

“…During the remote sensing at the angle, a polarization effect must occur [2]. Such an effect is due to the deformation of the raindrops (round drops become flatter) and it has not been investigated yet.…”

Millimeter and terahertz wave scattering diagrams in rains

“…В литературе их часто называют инди-катрисами рассеяния, а иногда, при использова-нии параметров Стокса и матричного представле-ния, именуют фазовыми функциями рассеяния [1]. В частности, для дистанционного зондирования [2,3] такие угловые характеристики необходимы при решении теоретических задач о переносе микро-волнового излучения в разнообразных рассеи-вающих средах, в том числе в дождях [4]. Одним из примеров практического применения сведений об индикатрисах рассеяния является использова-ние их при оценке влияния дождей на характери-стики сопровождения целей двухпозиционными радиолокационными станциями (РЛС) (в этом случае их называют бистатическими коэффици-ентами рассеяния), а также при оценке дополни-тельных помех в линиях связи.…”

Intensity and polarization of thermal radiation of three-dimensional rain cells in the microwave band

“…Due to this and other directions of research, interaction of microwave radiation with precipitations and clouds of various types is now extensively studied [3][4][5][6][7][8][9][10][11][12][13]. Many of them consist of non-spherical particles, having prevalent orientation like falling raindrops.…”