Academic Publications

2014
Sebastian D. Eastham, Debra K. Weisenstein, and Steven R. H. Barrett. 2014. “Development and evaluation of the unified tropospheric–stratospheric chemistry extension (UCX) for the global chemistry-transport model GEOS-Chem.” Atmospheric Environment, 89, Pp. 52-63. Publisher's VersionAbstract

Global chemistry-transport models (CTMs) typically use simplified parameterizations or relaxation to climatology to estimate the chemical behavior of the stratosphere only in the context of its impact on tropospheric chemistry. This limits investigation of stratospheric chemistry and interactions between tropospheric and stratospheric chemistry-transport processes. We incorporate stratospheric chemical and physical processes into the model GEOS-Chem in the form of a unified chemistry extension (UCX). The stratospheric chemistry framework from NASA’s Global Modeling Initiative (GMI) is updated in accordance with JPL 10-06 and combined with GEOS-Chem’s existing widely applied and validated tropospheric chemistry to form a single, unified gas-phase chemistry scheme. Aerosol calculations are extended to include heterogeneous halogen chemistry and the formation, sedimentation and evaporation of polar stratospheric clouds (PSCs) as well as background liquid binary sulfate (LBS) aerosols. The Fast-JX v7.0a photolysis scheme replaces a hybrid of Fast-J and Fast-JX v6.2, allowing photolytic destruction at frequencies relevant to the stratosphere and of species not previously modeled. Finally, new boundary conditions are implemented to cover both surface emissions of new species and mesospheric behavior. Results for four simulation years (2004-2007) are compared to those from the original, tropospheric model and to in situ and satellite-based measurements. We use these comparisons to show that the extended model is capable of modeling stratospheric chemistry efficiently without compromising the accuracy of the model at lower altitudes, perturbing mean OH below 250 hPa by less than 5% while successfully capturing stratospheric behavior not previously captured in GEOS-Chem such as formation and collapse of the Antarctic ozone hole. These extensions (with supporting validation and intercomparison) enable an existing and extensively validated tropospheric CTM to be used to investigate a broader set of atmospheric chemistry problems and leverages GEOS-Chem’s existing tropospheric treatment.

Eastham Weisenstein Barrett 2014
David Keith, Riley Duren, and Douglas MacMartin. 2014. “Field experiments on solar geoengineering: report of a workshop exploring a representative research portfolio.” Philosophical Transactions of the Royal Society A, 372. Publisher's Version 171.keith_.fieldexperimentsonsolargeoengineering.pdf
MacMartin, D. G., B. Kravitz, and D. W. Keith. 2014. “Geoengineering: the world’s largest control problem.” American Control Conference, Pp. 2401-2406. Publisher's Version 168.macmartin.controlproblem.pdf
Ben Kravitz, Douglas MacMartin, Alan Robock, Philip Rasch, Katharine Ricke, Jason Cole, Charles Curry, Pete Irvine, Duoying Ji, David Keith, Jon Egill Kristjánsson, John Moore, Helene Muri, Balwinder Singh, Simone Tilmes, Shingo Watanabe, Shuting Yang, and Jin-Ho Yoon. 2014. “A multi-model assessment of regional climate disparities caused by solar geoengineering.” Environmental Research Letters, 9. Publisher's Version kravitz_et_al._-_2014_-_a_multi-model_assessment_of_regional_climate_dispa.pdf
David Keith. 2014. “Not a superpower.” Policy Options, 35, Pp. 18-20. Publisher's Version 170.keith_.notasuperpower.pdf
Joshua Horton. 2014. “Solar Geoengineering: Reassessing Benefits, Costs, and Compensation.” Ethics, Policy & Environment. Publisher's Version
Douglas MacMartin, Ken Caldeira, and David Keith. 2014. “Solar geoengineering to limit rate of temperature change.” Philosophical Transactions of the Royal Society A, 372. Publisher's Version 172.macmartin.caldeira.keith_.solargeoengineeringtolimittherateoftemperaturechange.pdf
John Dykema, David Keith, James G. Anderson, and Debra Weisenstein. 2014. “Stratospheric controlled perturbation experiment (SCoPEx): a small-scale experiment to improve understanding of the risks of solar geoengineering.” Philosophical Transactions of the Royal Society A, 372. Publisher's Version dykema_et_al._-_2014_-_stratospheric_controlled_perturbation_experiment_.pdf
2013
Amanda Adams and David Keith. 2013. “Are global wind power resource estimates overstated?” Environmental Research Letters, 8. Publisher's Version 160.adams_.keith_.globalwindpowerestimates.e.pdf
Hossein Safaei, David Keith, and Ronald Hugo. 2013. “Compressed Air Energy Storage (CAES) with compressors distributed at heat loads to enable waste heat utilization.” Journal of Applied Energy, 103, Pp. 165-179. Publisher's Version 156.safaei.keith_.hugo_.caes_.e.pdf
Hossein Safaei and David Keith. 2013. “Compressed air energy storage with waste heat export: An Alberta case study.” Energy Conversion and Management, 78, Pp. 114–124. Publisher's Version 164.safaei.keith_.compressedairenergystor.p.pdf
Douglas MacMartin, Ben Kravitz, David Keith, and Andrew Jarvis. 2013. “Dynamics of the coupled human-climate system resulting from closed-loop control of solar geoengineering.” Climate Dynamics, 43, Pp. 243-258. Publisher's Version 165.macmartin.keith_.etal_.dynamicsofthecoupledhuman-climatesystem.pdf
Edward Parson and David Keith. 2013. “End the Deadlock on Governance of Geoengineering Research.” Science, 339, Pp. 1278-1279. Publisher's Version 163.parson.keith_.deadlockongonvernance.p.pdf
David Keith and Andy Parker. 2013. “The fate of an engineered planet.” Scientific American, 308, Pp. 34-36. Publisher's Version 161.keith_.parker.engineeredplanet.e.pdf
Wylie Carr, Christopher Preston, Laurie Yung, David Keith, Bronislaw Szerszynski, and Ashley Mercer. 2013. “Public Engagement on Solar Radiation Management and Why it Needs to Happen Now.” Nature Climate Change. Publisher's Version 157.carr_.etal_publicengageonsrm.p.pdf
Joshua Horton, Andy Parker, and David Keith. 2013. “Solar Geoengineering and the Problem of Liability.” Geoengineering Our Climate Working Paper and Opinion Article Series. Publisher's Version 166.horton_etal.solargeoliabilty.e.pdf
2012
Geoffrey Holmes and David Keith. 2012. “An Air-Liquid Contactor for Large-Scale Capture of CO2 from Air.” Philosophical Transactions of the Royal Society A – Mathematical, Physical & Engineering Sciences, 370, Pp. 4380-4403. Publisher's Version 148.holmes.keith_.contactorforlargescalecapture.e.pdf
Juan Moreno-Cruz and David Keith. 2012. “Climate Policy under Uncertainty: A Case for Geoengineering.” Climatic Change. Publisher's Version 117.moreno-cruz.climpoluncert-caseforgeoeng.e.pdf
Justin McClellan, David Keith, and Jay Apt. 2012. “Cost analysis of stratospheric albedo modification delivery systems.” Environmental Research Letters, 7. Publisher's Version 159.mcclellan.2012.costanalysisofstratosp.e.pdf
Douglas MacMartin, David Keith, Ben Kravitz, and Ken Caldeira. 2012. “Management of trade-offs in geoengineering through optimal choice of non-uniform radiative forcing.” Nature Climate Change, 3, Pp. 365-368. Publisher's Version 158.1macmartin.etal_.managingtradeoffsthroughnonradforc.e.pdf

Pages