Fundamental puzzles of climate science remain unsolved because of our limited understanding of how clouds, circulation and climate interact. One example is our inability to provide robust assessments of future global and regional climate changes. However, ongoing advances in our capacity to observe, simulate and conceptualize the climate system now make it possible to fill gaps in our knowledge. We argue that progress can be accelerated by focusing research on a handful of important scientific questions that have become tractable as a result of recent advances. We propose four such questions below; they involve understanding the role of cloud feedbacks and convective organization in climate, and the factors that control the position, the strength and the variability of the tropical rain belts and the extratropical storm tracks.
LMD/IPSL, CNRS, Université Pierre et Marie Curie, 4 Place Jussieu, Paris, France; Max Planck Institute for Meteorology, Bundesstrasse 53, Hamburg, Germany; Department of Atmospheric Sciences, University of Washington, Seattle, WA, United States; School of Mathematical Sciences, Monash University, Clayton, VIC, Australia; LSCE/IPSL, CEA-CNRS-UVSQ, UMR 8212, Gif-sur-Yvette, France; University of Colorado,Boulder, CIRES, 216 UCB, Boulder, CO, United States; NOAA/Earth System Research Lab, Physical Sciences Division, Boulder, CO, United States; Department of Meteorology, University of Reading, Reading, United Kingdom; Climate Change Research Centre, ARC Centre of Excellence for Climate System Science, University of New South Wales, Sydney, Australia; KNMI, Postbus 201, De Bilt, Netherlands; Department of Applied Physics and Applied Mathematics, Columbia University, New York, NY, United States; Atmosphere and Ocean Research Institute, University of Tokyo, Chiba, Japan; Hadley Centre, Met Office, Exeter, United Kingdom