Constraining global aerosol emissions using POLDER/PARASOL satellite remote sensing observations

Abstract

We invert global black carbon (BC), organic carbon (OC) and desert dust (DD) aerosol emissions from POLDER/PARASOL spectral aerosol optical depth (AOD) and aerosol absorption optical depth (AAOD) using the GEOS-Chem inverse modeling framework. Our inverse modeling framework uses standard a priori emissions to provide a posteriori emissions that are constrained by POLDER/PARASOL AODs and AAODs. The following global emission values were retrieved for the three aerosol components: 18.4 Tg yr −1 for BC, 109.9 Tg yr −1 for OC and 731.6 Tg yr −1 for DD for the year 2010. These values show a difference of +166.7 %, +184.0 % and −42.4 %, respectively, with respect to the a priori values of emission inventories used in "standard" GEOS-Chem runs. The model simulations using a posteriori emissions (i.e., retrieved emissions) provide values of 0.119 for global mean AOD and 0.0071 for AAOD at 550 nm, which are +13.3 % and +82.1 %, respectively, higher than the AOD and AAOD obtained using the a priori values of emissions. Additionally, the a posteriori model simulation of AOD, AAOD, single scattering albedo, Ångström exponent and absorption Ångström exponent show better agreement with independent AERONET, MODIS and OMI measurements than the a priori simulation. Thus, this study suggests that using satellite-constrained global aerosol emissions in aerosol transport models can improve the accuracy of simulated global aerosol properties.

Retrieval of aerosol properties from Airborne Hyper-Angular Rainbow Polarimeter (AirHARP) observations during ACEPOL 2017

“…Overall, the performance of the AirHARP observations plus the GRASP retrieval algorithm gives a good agreement with the collocated AERONET observations, especially when the GRASP/Models kernel is used. The above tendency is well identified in the in-depth analysis of PARASOL data processing using different retrieval setups by Chen et al (2020).…”

“…The reduction of sought unknowns helps situations in lower information content (e.g., for low AOD) and makes the separation of the surface and aerosol signal much less complicated compared to a GRASP/Five mode kernel. This tendency is well identified in the in-depth analysis of PARASOL data processing using different retrieval setups by Chen et al (2020). Like the GRASP/Five mode kernel, the state vector a includes the information on aerosol layer height.…”

Synergy processing of diverse ground-based remote sensing and in situ data using GRASP algorithm: applications to radiometer, lidar and radiosonde observations

“…(8) illustrates a more complex (non-linear) internal mixture of refractive indices of different components. For example, Li et al (2019Li et al ( , 2020 used the approximations of volume mixture (Eq. 7) and 225…”

Validation of GRASP algorithm product from POLDER/PARASOL data and assessment of multi-angular polarimetry potential for aerosol monitoring

“…It should be noted that GRASP is a flexible inversion algorithm that can be applied to a wide variety of satellite, ground-based and laboratory observations. It has already been applied to ground-based AERONET photometers and LiDARs (Benavent-Oltra et al, 2017, 2019Hu et al, 2019;Lopatin et al, 2013;Titos et al, 2019;Tsekeri et al, 2017), sky cameras (Román et al, 2017), polar-nephelometer data (Espinosa et al, 2017(Espinosa et al, , 2019, and surface measurements of AOD (Torres et al, 2017). In addition, GRASP is being used for several satellite instruments; aerosol products were generated for POLDER observations (discussed here) and for MERIS/Envisat, and there are ongoing developments for producing GRASP aerosol products from Sentinel-3 and -5P observations and operational aerosol retrievals for future Sentinel-4 and 3MI/Metop missions.…”

“…PARASOL/GRASP aerosol products have already appeared in many studies, i.e. validation (Tan et al, 2019;Wei et al, 2019Wei et al, , 2020, data assimilation (Chen et al, 2018(Chen et al, , 2019, AOD products merging Sogacheva et al, 2020). Despite these preliminary applications of the products, no systematic evaluation of the global PARASOL/GRASP aerosol products has been published.…”