Spatial patterns of shallow clouds: Challenging the concept of defined regimes

article Spatial patterns of shallow clouds: Challenging the concept of defined regimes published yes Giovanni Biagioli author Giulio Mandorli author Lilli Johanna Freischem author Alejandro Casallas Garcia author 92081129-2d75-11ef-a48d-b04dd7a2385a0000-0002-1988-5035 Adrian Mark Tompkins author CaMu department IST-BRIDGE: International postdoctoral program project Tropical shallow clouds are a major source of uncertainty in Earth's climate sensitivity, especially through their spatial arrangement, which global climate models do not represent. Efforts to understand their organization have partly relied on classifying observed scenes, identifying four patterns as archetypal regimes. Here we analyze geostationary satellite imagery of the western tropical Atlantic using the L‐function, a tool based on point pattern theory that quantifies cloud organization across spatial scales. Classical examples of the four patterns show distinct L‐function fingerprints, revealing their characteristic clustering and regularity scales and aiding physical interpretation. Yet, when evaluating many scenes at fixed spatial scales, the L‐function distribution lacks the distinct modes expected from discrete regimes. This is corroborated by analyses of other organization indices employing diverse approaches, from inter‐cloud nearest‐neighbor distances to fractal analysis. Implications for the parameterization of mesoscale cloud organization in climate models are discussed. https://research-explorer.ista.ac.at/download/21755/21756/Gio_Casallas_2026.pdf application/pdfno Wiley2026 eng Geophysical Research Letters 0094-8276 1944-800710.1029/2025gl119921 538 Biagioli, G., Mandorli, G., Freischem, L. J., Casallas Garcia, A., & Tompkins, A. M. (2026). Spatial patterns of shallow clouds: Challenging the concept of defined regimes. Geophysical Research Letters. Wiley. <a href="https://doi.org/10.1029/2025gl119921">https://doi.org/10.1029/2025gl119921</a> Biagioli, Giovanni, Giulio Mandorli, Lilli Johanna Freischem, Alejandro Casallas Garcia, and Adrian Mark Tompkins. “Spatial Patterns of Shallow Clouds: Challenging the Concept of Defined Regimes.” Geophysical Research Letters. Wiley, 2026. <a href="https://doi.org/10.1029/2025gl119921">https://doi.org/10.1029/2025gl119921</a>. Biagioli G, Mandorli G, Freischem LJ, Casallas Garcia A, Tompkins AM. Spatial patterns of shallow clouds: Challenging the concept of defined regimes. Geophysical Research Letters. 2026;53(8). doi:<a href="https://doi.org/10.1029/2025gl119921">10.1029/2025gl119921</a> G. Biagioli, G. Mandorli, L.J. Freischem, A. Casallas Garcia, A.M. Tompkins, Geophysical Research Letters 53 (2026). Biagioli G, Mandorli G, Freischem LJ, Casallas Garcia A, Tompkins AM. 2026. Spatial patterns of shallow clouds: Challenging the concept of defined regimes. Geophysical Research Letters. 53(8), e2025GL119921. Biagioli, Giovanni, et al. “Spatial Patterns of Shallow Clouds: Challenging the Concept of Defined Regimes.” Geophysical Research Letters, vol. 53, no. 8, e2025GL119921, Wiley, 2026, doi:<a href="https://doi.org/10.1029/2025gl119921">10.1029/2025gl119921</a>. G. Biagioli, G. Mandorli, L. J. Freischem, A. Casallas Garcia, and A. M. Tompkins, “Spatial patterns of shallow clouds: Challenging the concept of defined regimes,” Geophysical Research Letters, vol. 53, no. 8. Wiley, 2026. 217552026-04-21T06:04:41Z2026-04-28T13:35:53Z