Impact of geoengineered aerosols on the troposphere and stratosphere

Journal Article · Sat Jun 27 04:00:00 EDT 2009 · Journal of Geophysical Research. D. (Atmospheres), 114:Article No. D12305

DOI:https://doi.org/10.1029/2008JD011420· OSTI ID:1008259

Tilmes, S; Garcia, Rolando R; Kinnison, Douglas E; Gettelman, A; Rasch, Philip J

A coupled chemistry climate model, the Whole Atmosphere Community Climate Model was used to perform a transient climate simulation to quantify the impact of geoengineered aerosols on atmospheric processes. In contrast to previous model studies, the impact on stratospheric chemistry, including heterogeneous chemistry in the polar regions, is considered in this simulation. In the geoengineering simulation, a constant stratospheric distribution of volcanic-sized, liquid sulfate aerosols is imposed in the period 2020–2050, corresponding to an injection of 2 Tg S/a. The aerosol cools the troposphere compared to a baseline simulation. Assuming an Intergovernmental Panel on Climate Change A1B emission scenario, global warming is delayed by about 40 years in the troposphere with respect to the baseline scenario. Large local changes of precipitation and temperatures may occur as a result of geoengineering. Comparison with simulations carried out with the Community Atmosphere Model indicates the importance of stratospheric processes for estimating the impact of stratospheric aerosols on the Earth’s climate. Changes in stratospheric dynamics and chemistry, especially faster heterogeneous reactions, reduce the recovery of the ozone layer in middle and high latitudes for the Southern Hemisphere. In the geoengineering case, the recovery of the Antarctic ozone hole is delayed by about 30 years on the basis of this model simulation. For the Northern Hemisphere, a onefold to twofold increase of the chemical ozone depletion occurs owing to a simulated stronger polar vortex and colder temperatures compared to the baseline simulation, in agreement with observational estimates.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1008259
• Report Number(s): PNNL-SA-69985
• Journal Information: Journal of Geophysical Research. D. (Atmospheres), 114:Article No. D12305, Journal Name: Journal of Geophysical Research. D. (Atmospheres), 114:Article No. D12305 Vol. 114
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
AEROSOLS
CHEMISTRY
CLIMATE MODELS
CLIMATES
DISTRIBUTION
GREENHOUSE EFFECT
NORTHERN HEMISPHERE
OZONE
OZONE LAYER
POLAR REGIONS
PRECIPITATION
SIMULATION
SOUTHERN HEMISPHERE
STRATOSPHERE
SULFATES
TRANSIENTS
TROPOSPHERE