Weak liquid water path response in ship tracks

• DOI: 10.5194/egusphere-2024-1479
• Publication Date: 2024-05-22T14:03:33Z
• Authors: Anna Tippett; Edward Gryspeerdt; Peter Manshausen; Philip Stier; Tristan W. P. Smith
• Keywords: Liquid water

Abstract. The assessment of aerosol-cloud interactions remains a major source uncertainty in understanding climate change, partly due to the difficulty making accurate observations aerosol impacts on clouds. Ships can release large numbers aerosols that serve as cloud condensation nuclei, which create artificially brightened clouds known ship tracks. These emissions offer "natural'', or "opportunistic'', experiment explore effects while disentangling meteorological influences. Utilising positions and reanalysis winds, we predict track locations, collocating them with satellite data depict temporal evolution properties after an perturbation. Repeating our analysis for null does not necessarily recover zero signal expected, but instead reveals subtleties between different methodologies. This study uncovers systematic bias prior research, assumption background gradients will, average, be linear. We correct this bias, is linked correlation wind fields properties, reveal true response. find liquid water path (LWP) response pertubation weak once corrected for. has important implications estimates radiative forcings LWP adjustments, previous responses unstable cases were overestimated. A noticeable only recovered specific cases, such marine stratocumulus clouds, where positive found precipitating clean work highlights isolated opportunistic experiments, reconciling differences reported studies.