Abstract
AbstractAerosol-cloud interactions are a major source of uncertainty in weather and climate models. These interactions and associated precipitation feedbacks are modulated by spatial distributions of aerosols on global and regional scales. Aerosols also vary on mesoscales, including around wildfires, industrial regions, and cities, but the impacts of variability on these scales are understudied. Here, we first present observations of covarying mesoscale aerosol and cloud distributions on the mesoscale. Then, using a high-resolution process model, we show that horizontal aerosol gradients of order 100 km drive a thermally-direct circulation we call an “aerosol breeze”. We find that aerosol breezes support initiation of clouds and precipitation over the low-aerosol portion of the gradient while suppressing their development on the high-aerosol end. Aerosol gradients also enhance domain-wide cloudiness and precipitation, compared with homogenous distributions of the same aerosol mass, leading to potential biases in models that do not adequately represent this mesoscale aerosol heterogeneity.
Funder
National Aeronautics and Space Administration
Publisher
Springer Science and Business Media LLC
Subject
General Physics and Astronomy,General Biochemistry, Genetics and Molecular Biology,General Chemistry,Multidisciplinary
Reference47 articles.
1. Boucher, O. et al. in Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change 571–658 (Cambridge University Press, 2013).
2. Kiehl, J. T. & Briegleb, B. P. The relative roles of sulfate aerosols and greenhouse gases in climate forcing. Science 260, 311–314 (1993).
3. Kim, D., Wang, C., Ekman, A. M. L., Barth, M. C. & Lee, D.-I. The responses of cloudiness to the direct radiative effect of sulfate and carbonaceous aerosols. J. Geophys. Res. Atmos. 119, 1172–1185 (2014).
4. Ramanathan, V. et al. Atmospheric brown clouds: impacts on South Asian climate and hydrological cycle. Proc. Natl Acad. Sci. USA 102, 5326–5333 (2005).
5. McCormick, R. A. & Ludwig, J. H. Climate modification by atmospheric aerosols. Science 156, 1358–1359 (1967).
Cited by
3 articles.
订阅此论文施引文献
订阅此论文施引文献，注册后可以免费订阅5篇论文的施引文献，订阅后可以查看论文全部施引文献