AEROCOM and AEROSAT AAOD and SSA study – Part 1: Evaluation and intercomparison of satellite measurements

• Published in: Atmospheric Chemistry and Physics
• Main Authors: N. Schutgens, O. Dubovik, O. Hasekamp, O. Torres, H. Jethva, P. J. T. Leonard, P. Litvinov, J. Redemann, Y. Shinozuka, G. de Leeuw, S. Kinne, T. Popp, M. Schulz, P. Stier
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2021
• Subjects: Physics; QC1-999; Chemistry; QD1-999; Aerosol Robotic Network
• Online Access: https://doi.org/10.5194/acp-21-6895-2021; https://doaj.org/article/ceced39c38f04da8a7990a40c0ee58ac

Global measurements of absorbing aerosol optical depth (AAOD) are scarce and mostly provided by the ground network AERONET (AErosol RObotic NETwork). In recent years, several satellite products of AAOD have been developed. This study's primary aim is to establish the usefulness of these datasets for AEROCOM (Aerosol Comparisons between Observations and Models) model evaluation with a focus on the years 2006, 2008 and 2010. The satellite products are super-observations consisting of <math xmlns="http://www.w3.org/1998/Math/MathML" id="M1" display="inline" overflow="scroll" dspmath="mathml"><mrow><mn mathvariant="normal">1</mn><msup><mi/><mo>∘</mo></msup><mo>×</mo><mn mathvariant="normal">1</mn><msup><mi/><mo>∘</mo></msup><mo>×</mo><mn mathvariant="normal">30</mn></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="57pt" height="11pt" class="svg-formula" dspmath="mathimg" md5hash="54d43dcfd45f49f6bd3e8b718d7a312d"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-21-6895-2021-ie00001.svg" width="57pt" height="11pt" src="acp-21-6895-2021-ie00001.png"/></svg:svg> min aggregated retrievals. This study consists of two papers, the current one that deals with the assessment of satellite observations and a second paper ( Schutgens et al. , 2021 ) that deals with the evaluation of models using those satellite data. In particular, the current paper details an evaluation with AERONET observations from the sparse AERONET network as well as a global intercomparison of satellite datasets, with a focus on how minimum AOD (aerosol optical depth) thresholds and temporal averaging may improve agreement between satellite observations. All satellite datasets are shown to have reasonable skill for AAOD (three out of four datasets show correlations with AERONET in excess of 0.6) but less skill for SSA (single-scattering albedo; only one ...