Remote sensing of aerosols by using polarized, directional and spectral measurements within the A-Train: the PARASOL mission

Abstract

Abstract. Instruments dedicated to aerosol monitoring are recently available and the POLDER (POLarization and Directionality of the Earth's Reflectances) instrument on board the PARASOL (Polarization & Anisotropy of Reflectances for Atmospheric Sciences coupled with Observations from a Lidar) mission is one of them. By measuring the spectral, angular and polarization properties of the radiance at the top of the atmosphere, in coordination with the other A-Train instruments, PARASOL provides the aerosol optical depths (AOD) as well as several optical and microphysical aerosol properties. The instrument, the inversion schemes and the list of aerosol parameters are described. Examples of retrieved aerosol parameters are provided as well as innovative approaches and further inversion techniques.

Impact of cloud horizontal inhomogeneity and directional sampling on the retrieval of cloud droplet size by the POLDER instrument

“…For noise contributions larger than the 10 % of the signal, the RMSE values of the CDR estimate increase rapidly. The instrument-and calibrationrelated noise in the POLDER-measured polarized reflectance values is considered to be within 3 % (van Diedenhoven et al, 2012;Fougnie et al, 2007). These results confirm that the inversion is robust as long as the noise contributions do not exceed 10 % of the valid signal, even if the observations are limited.…”

“…It is a multi-spectral imaging polarimeter composed of a 2-D charged coupled device (CCD) detector array, a rotating wheel with spectral filters and polarizers, and wide field-of-view (1800 km) telecentric optics (Parol et al, 2004;Tanré et al, 2011). The CCD detector array provides a spatial resolution of approximately 6 km at nadir.…”

“…To analyze the noise sensitivity of the droplet size retrieval, we added Gaussian noise with increasing standard deviation to the simulated polarized reflectances (van Diedenhoven et al, 2012). Retrievals at 865 nm with actual CDR values of 5-20 µm and actual EV value of 0.05 were evaluated.…”

La contribution du spatial en France aux sciences de l'atmosphère et du climat

“…La carte globale d'ozone peut être présentée à la résolution des observations (niveau 2) ou sous forme de moyenne (niveau 3), avant d'être assimilée dans un modèle de chimie-transport (niveau 4). Clerbaux et al, 2009 ;Menut et al, 2017 pour les aspects composition atmosphérique), Polder et Calipso (aérosols et nuages, voir Tanré et al, 2011 ;Zeng et al, 2011et Winker et al, 2009 ; voir aussi encadré 6). De futures missions/ instruments sont aujourd'hui en phase A, B ou C, comme par exemple Iasi-NG (Crevoisier et al, 2014), Biomass (Scipal et al, 2010), Flex (Kraft et al, 2012), CFOsat (Caudal et al, 2014), Swarm (Mandéa, 2016), Swot (Gaultier et al, 2016), Merlin et Microcarb (voir Chevallier et al, 2017, pour plus …”

Role of Coarse and Fine Mode Aerosols in MODIS AOD Retrieval: a case study over southern India

“…Hence, spaceborne platforms are necessary to observe aerosol properties over global or continental scale. A considerable progress has been made to estimate AOD from space-borne platforms in past two decades (Martonchik et al, 1998;Ignatov et al, 2004;Remer et al, 2005Remer et al, , 2008Kokhanovsky et al, 2007;Laszlo et al, 2008;Livingston et al, 2009;Kahn et al, 2010;Tanré et al, 2011;Hsu et al, 2012). However, only few satellite sensors are able to provide AOD over land and the retrieval of other aerosol properties like size distribution, single scattering albedo or refractive-index remains to be a challenging task.…”