A near-global multiyear climate data record of the submicrometer-mode and supermicrometer-mode components of atmospheric pure-dust

Significant is the complex role of atmospheric dust in the climate system, environmental conditions, and human health. However, the impact of dust layers residing in the atmosphere vary strongly based on the mineral dust physical and chemical properties as well as the particle size distribution, ranging from less than 0.1 μm to over 100 μm in diameter. More specifically, it is documented that larger mineral dust particles are more efficiently removed through dry deposition near the source regions and act more efficiently as CCN and/or IN, while fine dust particles are more prone to long-range transport, affecting air quality and human health over distances of thousands of kilometers downwind.Here, a new four-dimensional, multiyear, and near-global climate data record is introduced, established with the overarching objective to decouple the submicrometer and supermicrometer components in terms of diameter of atmospheric dust layers. More specifically, this separation is realized through a combination of (1) the total pure-dust product from the ESA-LIVAS database, and (2) the supermicrometer-mode component of atmospheric dust, as extracted through implementation of the first step of the two-step POLIPHON technique. Accordingly, the submicrometer-mode component of atmospheric dust is derived as the residual between the total pure-dust and supermicrometer-mode component of pure-dust.The decoupling scheme is applied to CALIPSO observations at 532nm, resulting in quality-assured profiles of backscatter coefficient at 532nm, extinction coefficient at 532nm, and mass concentration, for both submicrometer-mode and supermicrometer-mode of atmospheric pure-dust. These datasets are established with original CALIOP resolution along the CALIPSO orbit-path and in averaged profiles of 1ox1o spatial and seasonal temporal resolution, covering over 15 years of Earth Observation. This climate data record is considered unique, providing valuable insight into the characteristics of the atmospheric pure-dust components, thus contributing to a better understanding of their impact on climate, environment, and human health.Acknowledgements The research study was supported by the AXA Research Fund for postdoctoral researchers under the project entitled “Earth Observation for Air-Quality - Dust Fine-Mode (EO4AQ-DustFM)”.