Black carbon aerosol-induced Northern Hemisphere tropical expansion [electronic resource].
- Washington, D.C. : United States. Dept. of Energy. Office of Science, 2015.
Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy
- Physical Description:
- pages 4,964-4,972 : digital, PDF file
- Additional Creators:
- Oak Ridge National Laboratory, United States. Department of Energy. Office of Science, and United States. Department of Energy. Office of Scientific and Technical Information
- Restrictions on Access:
- Free-to-read Unrestricted online access
- Global climate models (GCMs) underestimate the observed trend in tropical expansion. Recent studies partly attribute it to black carbon (BC) aerosols, which are poorly represented in GCMs. In this paper, we conduct a suite of idealized experiments with the Community Atmosphere Model version 4 coupled to a slab ocean model forced with increasing BC concentrations covering a large swath of the estimated range of current BC radiative forcing while maintaining their spatial distribution. The Northern Hemisphere (NH) tropics expand poleward nearly linearly as BC radiative forcing increases (0.7° W-1 m2), indicating that a realistic representation of BC could reduce GCM biases. We find support for the mechanism where BC-induced midlatitude tropospheric heating shifts the maximum meridional tropospheric temperature gradient poleward resulting in tropical expansion. Finally, we also find that the NH poleward tropical edge is nearly linearly correlated with the location of the Intertropical Convergence Zone, which shifts northward in response to increasing BC.
- Report Numbers:
- E 1.99:1324138
- Other Subject(s):
- Published through SciTech Connect.
Geophysical Research Letters 42 12 ISSN 0094-8276 AM
Mahesh Kovilakam; Salil Mahajan.
- Funding Information:
View MARC record | catkey: 23777141