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Microphysical simulations of large volcanic eruptions: Pinatubo and Toba
Simulations of stratospheric clouds from eruptions ranging in size from the 1991 eruption of Mount Pinatubo to that of Toba 74,000 years ago have been completed using a 3D microphysical sectional
Ubiquitous low‐level liquid‐containing Arctic clouds: New observations and climate model constraints from CALIPSO‐GOCCP
Ground‐based observations show that persistent liquid‐containing Arctic clouds occur frequently and have a dominant influence on Arctic surface radiative fluxes. Yet, without a hemispheric multi‐year
Microphysical simulations of new particle formation in the upper troposphere and lower stratosphere
Abstract. Using a three-dimensional general circulation model with sulfur chemistry and sectional aerosol microphysics (WACCM/CARMA), we studied aerosol formation and microphysics in the upper
Microphysical simulations of sulfur burdens from stratospheric sulfur geoengineering
Abstract. Recent microphysical studies suggest that geoengineering by continuous stratospheric injection of SO2 gas may be limited by the growth of the aerosols. We study the efficacy of SO2, H2SO4
Contributions of Clouds, Surface Albedos, and Mixed-Phase Ice Nucleation Schemes to Arctic Radiation Biases in CAM5
AbstractThe Arctic radiation balance is strongly affected by clouds and surface albedo. Prior work has identified Arctic cloud liquid water path (LWP) and surface radiative flux biases in the
Implications of extinction due to meteoritic smoke in the upper stratosphere
Recent optical observations of aerosols in the upper stratosphere and mesosphere show significant amounts of extinction at altitudes above about 40 km where the stratospheric sulfate aerosol layer
Recent anthropogenic increases in SO2 from Asia have minimal impact on stratospheric aerosol
Observations suggest that the optical depth of the stratospheric aerosol layer between 20 and 30 km has increased 4–10% per year since 2000, which is significant for Earth's climate. Contributions to
Arctic Radiative Fluxes: Present-Day Biases and Future Projections in CMIP5 Models
AbstractRadiative fluxes are critical for understanding the energy budget of the Arctic region, where the climate has been changing rapidly and is projected to continue to change. This work
Development of a Polar Stratospheric Cloud Model within the Community Earth System Model using constraints on Type I PSCs from the 2010–2011 Arctic winter
Polar stratospheric clouds (PSCs) are critical elements of Arctic and Antarctic ozone depletion. We establish a PSC microphysics model using coupled chemistry, climate, and microphysics models driven
The Geoengineering Model Intercomparison Project Phase 6 (GeoMIP6): simulation design and preliminary results
A suite of new climate model experiment designs for the Geoengineering Model Intercomparison Project (GeoMIP), which has been expanded to address several further important topics, including key uncertainties in extreme events, the use of geoengineering as part of a portfolio of responses to climate change, and the relatively new idea of cirrus cloud thinning to allow more longwave radiation to escape to space.