Projected Response of Low‐Level Convergence and Associated Precipitation to Greenhouse Warming
preprintposted on 19.06.2019, 06:19 by Evan Weller, Christian Jakob, Michael J. Reeder
The parameterization of convection in climate models is a large source of uncertainty in projecting future precipitation changes. Here an objective method to identify organized low‐level convergence lines has been used to better understand how atmospheric convection is organized and projected to change, as low‐level convergence plays an important role in the processes leading to precipitation. The frequency and strength of convergence lines over both ocean and land in current climate simulations is too low compared to reanalysis data. Projections show a further reduction in the frequency and strength of convergence lines over the midlatitudes. In the tropics, the largest changes in frequency are generally associated with shifts in major low‐latitude convergence zones, consistent with changes in the precipitation. Further, examining convergence lines when in the presence or absence of precipitation results in large spatial contrasts, providing a better understanding of regional changes in terms of thermodynamic and dynamic effects.
"This is the pre-peer reviewed version of the following article: [Weller, E., Jakob, C., & Reeder, M. J. ( 2017). Projected response of low‐level convergence and associated precipitation to greenhouse warming. Geophysical Research Letters, 44, 10,682– 10,690. https://doi.org/10.1002/2017GL075489], which has been published in final form. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions."