A global survey of the instantaneous linkages between cloud vertical structure and large-scale climate

• Published in: Journal of Geophysical Research: Atmospheres
• Main Authors: Li, Ying, Thompson, David W. J., Stephens, Graeme L., Bony, Sandrine
• Other Authors: Department of Atmospheric Science Fort Collins, Colorado State University Fort Collins (CSU), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X), Institut Polytechnique de Paris (IP Paris)-Institut Polytechnique de Paris (IP Paris)-École nationale des ponts et chaussées (ENPC)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS-PSL, École normale supérieure - Paris (ENS-PSL), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)
• Format: Article in Journal/Newspaper
• Language: English
• Published: CCSD 2014
• Subjects: [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology; Arctic
• Online Access: https://polytechnique.hal.science/hal-01074224; https://polytechnique.hal.science/hal-01074224v1/document; https://polytechnique.hal.science/hal-01074224v1/file/2013JD020669.pdf; https://doi.org/10.1002/2013JD020669

International audience The instantaneous linkages between cloud vertical structure and various large-scale meteorological parameters are investigated using 5 years of data from the CloudSat/CALIPSO instruments. The linkages are systemically explored and quantified at all vertical levels and throughout the global ocean in both the long-term mean and on month-to-month timescales. A number of novel large-scale meteorological parameters are used in the analysis, including tropopause temperatures, upper tropospheric stability, and storm track activity. The results provide a baseline for evaluating physical parameterizations of clouds in GCMs and a reference for interpreting the signatures of large-scale atmospheric phenomena in cloud vertical structure. In the long-term mean, upper tropospheric cloud incidence throughout the globe increases with (1) decreasing tropopause temperature (at a rate of ∼2–4% K−1), (2) decreasing upper tropospheric stability (∼5–10% per K km−1), and (3) increasing large-scale vertical motion (∼1–4% per 10 hPa d−1). In contrast, lower tropospheric cloud incidence increases with (1) increasing lower tropospheric stability (10% per K km−1) and descending motion (1% per 10 hPa d−1) in regions of subtropical regime but (2) decreasing lower tropospheric stability (4% per K km−1) and ascending motion (2% per 10 hPa d−1) over the Arctic region. Variations in static stability and vertical motion account for ∼20–35% of the month-to-month variance in upper tropospheric cloudiness but less than 10% of the variance in lower tropospheric clouds. Upper tropospheric cloud incidence in the storm track regions is strongly linked to the variance of large-scale vertical motion and thus the amplitude of baroclinic waves.