Spatiotemporal characteristics of aerosols and low clouds from MODIS and their implications for marine cloud brightening

[Geoengineering News]

https://link.springer.com/article/10.1007/s11430-025-1794-7

Authors: Liya Niu, Chuanfeng Zhao, Haotian Zhang, Yongen Liang & Annan Chen 

26 February 2026

Abstract

Marine cloud brightening (MCB), a regional solar radiation modification geoengineering approach, has drawn significant attention regarding its feasibility and risk assessment. Based on MODIS satellite remote sensing data from 2003 to 2024, this study analyzes the spatiotemporal distribution characteristics and correlations of aerosol optical depth (AOD), cloud droplet effective radius (CER), cloud optical thickness (COT), and cloud fraction (CF) globally. Building on these results, five representative regions were selected to quantify the sensitivity of low-cloud characteristics to AOD, followed by an assessment of the global MCB potential. The results indicate that in the North Pacific region, particularly during autumn (SON), CF, COT, and CER exhibit favorable synergistic enhancement effects. However, these regions demonstrate both high sensitivity in cloud characteristic responses and significant heterogeneity in responses across different areas. Furthermore, the study revealed decoupling phenomena in the responses of cloud macro- and micro-physical characteristics in certain sea areas, where CER did not decrease despite increases in CF and COT with AOD. Distinct physical pathways of cloud response are also identified, manifesting as either “cloud area expansion” or “cloud thickening”. Integrating these findings, this study provides a foundational understanding for elucidating aerosol-low cloud interaction mechanisms and advancing MCB geoengineering research. Specifically, an effective MCB potential assessment framework must transcend static climatological screening toward dynamic systems analysis of sensitivity and robustness, macro-micro response synergy, and evolving background climate states, thereby supporting more rigorous scientific evaluation of this geoengineering strategy.

Source: Springer Nature Link