Marie McGrawPhD Candidate, Barnes Research Group
email: mmcgraw at atmos dot colostate dot edu
Impact of Volcanic Eruptions on ClimateWe used over 200 model runs from CMIP5 and the NCAR CESM Large Ensemble to evaluate the Southern Hemisphere circulation response to volcanic eruptions. Observations of volcanic eruptions are limited, so we can use models to understand the observed responses in the context of internal climate variability, and of the El Nino-Southern Oscillation.
- McGraw, Marie C., Elizabeth A. Barnes, and Clara Deser: Reconciling the Observed and Modeled Southern Hemisphere Circulation Response to Volcanic Eruptions.** Geophys. Res. Lett., doi:10.1002/2016GL069835.
- This research was also featured in an Eos research spotlight.
Seasonal Sensitivity of the Midlatitude Jet to Heating
Idealized ModelsWe used an idealized model (the publicly-available GFDL dry dynamical core) to explore the seasonal sensitivity of the eddy-driven jet to tropospheric heating. We kept the heating constant and allowed the atmosphere to vary according to season by adjusting the relaxation temperature. You can see some of the heating experiments we performed here.
Bug in Some Versions of GFDL Source CodeWhile performing our experiments, we stumbled across a bug in our version of the GFDL dry dynamical core. We used the troposphere-only model configuration, which imposes a minimum temperature of 200 K on the tropospheric equilibrium temperature profile. Our version of the model allowed this minimum temperature to vary with season, and this seasonal variation had an enormous impact on the jet dynamics. The Appendix and Figure A1 in McGraw and Barnes (2016) discusses this issue in more detail. Note that this error only affects the troposphere-only configuration.
- McGraw, Marie C., and Elizabeth A. Barnes: Seasonal Sensitivity of the Eddy-Driven Jet to Tropospheric Heating in an Idealized AGCM.* J. Climate, 29, doi:10.1175/JCLI-D-15-0723.1
* Downloads courtesy of the American Meteorological Society (AMS), who owns sole rights to them. The downloads are subject to AMS copyright laws and statutes. For more information, visit the AMS Journals website.
** Downloads courtesy of the American Geophysical Union (AGU), who owns sole rights to them. The downloads are subject to AGU copyright laws and statutes. For more information, visit the AGU website.