A5019602067- Geological Studies and Exploration
- Geology and Paleoclimatology Research
- Geological and Geophysical Studies
- Climate variability and models
- Geophysics and Gravity Measurements
- Geological and Geochemical Analysis
- Atmospheric Ozone and Climate
- Atmospheric chemistry and aerosols
- Atmospheric and Environmental Gas Dynamics
- Physics and Engineering Research Articles
- Chalcogenide Semiconductor Thin Films
- Gamma-ray bursts and supernovae
- Climate Change and Geoengineering
- Astronomy and Astrophysical Research
- Nuclear Materials and Properties
- Astro and Planetary Science
- Atmospheric aerosols and clouds
- Planetary Science and Exploration
- Ionosphere and magnetosphere dynamics
- Laser Design and Applications
- Methane Hydrates and Related Phenomena
- Solar and Space Plasma Dynamics
- Nuclear Issues and Defense
- Meteorological Phenomena and Simulations
- Space exploration and regulation
University of Arizona
2024
NSF National Center for Atmospheric Research
2014-2023
NOAA Earth System Research Laboratory
2014-2023
National Oceanic and Atmospheric Administration
1994-2023
Prism Eye Institute
2022-2023
James Graham Brown Foundation
2023
Climate and Global Dynamics Laboratory
2017-2022
High Altitude Observatory
2022
Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)
2022
Meteorological Research Institute
2022
An overview of the Community Earth System Model Version 2 (CESM2) is provided, including a discussion challenges encountered during its development and how they were addressed. In addition, an evaluation pair CESM2 long preindustrial control historical ensemble simulations presented. These performed using nominal 1° horizontal resolution configuration coupled model with both "low-top" (40 km, limited chemistry) "high-top" (130 comprehensive versions atmospheric component. contains many...
Abstract The NCAR Community Earth System Model (CESM) now includes an atmospheric component that extends in altitude to the lower thermosphere. This model, known as Whole Atmosphere Climate (WACCM), fully interactive chemistry, allowing, for example, a self-consistent representation of development and recovery stratospheric ozone hole its effect on troposphere. paper focuses analysis ensemble transient simulations using CESM1(WACCM), covering period from preindustrial era present day,...
Industrial chlorofluorocarbons that cause ozone depletion have been phased out under the Montreal Protocol. A chemically driven increase in polar (or "healing") is expected response to this historic agreement. Observations and model calculations together indicate healing of Antarctic layer has now begun occur during month September. Fingerprints September since 2000 include (i) increases column amounts, (ii) changes vertical profile concentration, (iii) decreases areal extent hole. Along...
Abstract The Whole Atmosphere Community Climate Model version 6 (WACCM6) is a major update of the whole atmosphere modeling capability in Earth System (CESM), featuring enhanced physical, chemical and aerosol parameterizations. This work describes WACCM6 some important features model. can reproduce many modes variability trends middle atmosphere, including quasi‐biennial oscillation, stratospheric sudden warmings, evolution Southern Hemisphere springtime ozone depletion over twentieth...
Abstract The Community Earth System Model version 2 (CESM2) includes a detailed representation of chemistry throughout the atmosphere in Atmosphere with and Whole Climate configurations. These model configurations use for Ozone Related chemical Tracers (MOZART) family mechanisms, covering troposphere, stratosphere, mesosphere, lower thermosphere. new MOZART tropospheric scheme (T1) has number updates over previous (MOZART‐4) CESM, including improvements to oxidation isoprene terpenes,...
Abstract The Community Earth System Model Version 2 (CESM2) has an equilibrium climate sensitivity (ECS) of 5.3 K. ECS is emergent property both feedbacks and aerosol forcing. increase in over the previous version (CESM1) result cloud feedbacks. Interim versions CESM2 had a land model that damped ECS. Part change results from evolving configuration to reproduce long‐term trend global regional surface temperature twentieth century response forcings. Changes made reduce aerosols also impacted...
Abstract Accurate representation of global stratospheric aerosols from volcanic and nonvolcanic sulfur emissions is key to understanding the cooling effects ozone losses that may be linked activity. Attribution climate variability activity particular interest in relation post‐2000 slowing rate average temperature increases. We have compiled a database SO 2 plume altitudes for eruptions 1990 2014 developed new prognostic capability simulating sulfate Community Earth System Model. used these...
[1] The hydrological impact of enhancing Earth's albedo by solar radiation management is investigated using simulations from 12 Earth System models contributing to the Geoengineering Model Intercomparison Project (GeoMIP). We contrast an idealized experiment, G1, where global mean radiative forcing kept at preindustrial conditions reducing insolation while CO2 concentration quadrupled a 4×CO2 experiment. reduction evapotranspiration over land with instantaneously increasing concentrations in...
This paper describes the Stratospheric Aerosol Geoengineering Large Ensemble (GLENS) project, which promotes use of a unique model dataset, performed with Community Earth System Model, Whole Atmosphere Climate Model as its atmospheric component [CESM1(WACCM)], to investigate global and regional impacts geoengineering. The simulations were designed achieve multiple simultaneous climate goals, by strategically placing sulfur injections at four different locations in stratosphere, unlike many...
We describe the first simulations of stratospheric sulfate aerosol geoengineering using multiple injection locations to meet simultaneous surface temperature objectives. Simulations were performed CESM1(WACCM), a coupled atmosphere-ocean general circulation model with fully interactive chemistry, dynamics (including an internally generated quasi-biennial oscillation), and sophisticated treatment formation, microphysical growth, deposition. The objectives are defined as maintaining three...
Abstract The Community Earth System Model version 2 (CESM2) includes three main atmospheric configurations: the Atmosphere 6 (CAM6) with simplified chemistry and a organic aerosol (OA) scheme, CAM6 comprehensive tropospheric stratospheric representation (CAM6‐chem), Whole Climate (WACCM6). Both, CAM6‐chem WACCM6 include more secondary aerosols (SOA) approach using Volatility Basis Set (VBS) scheme prognostic aerosols. This paper describes different OA schemes available in configurations of...
Abstract We present new insights into the evolution and interactions of stratospheric aerosol using an updated version Whole Atmosphere Community Climate Model (WACCM). Improved horizontal resolution, dynamics, chemistry now produce internally generated quasi‐biennial oscillation significant improvements to temperatures ozone compared observations. a validation WACCM column climate calculations against The prognostic treatment sulfate aerosols accurately represents optical depth...
Abstract Using volcanic sulfur dioxide emissions in an aerosol‐climate model, we derive a time series of global‐mean effective radiative forcing (ERF) from 1979 to 2015. For 2005–2015, calculate global multiannual mean ERF −0.08 W/m 2 relative the volcanically quiescent 1999–2002 period, due high frequency small‐to‐moderate‐magnitude explosive eruptions after 2004. large magnitude such as 1991 Mt. Pinatubo, our model‐simulated ERF, which accounts for rapid adjustments including aerosol...
Abstract. The enhancement of the stratospheric aerosol layer by volcanic eruptions induces a complex set responses causing global and regional climate effects on broad range timescales. Uncertainties exist regarding climatic response to strong forcing identified in coupled simulations that contributed fifth phase Coupled Model Intercomparison Project (CMIP5). In order better understand sources these model diversities, Volcanic (VolMIP) has defined coordinated idealized perturbation...
Abstract Geoengineering methods could potentially offset aspects of greenhouse gas‐driven climate change. However, before embarking on any such strategy, a comprehensive understanding its impacts must be obtained. Here, 20‐member ensemble simulations with the Community Earth System Model Whole Atmosphere Climate as atmospheric component is used to investigate projected hydroclimate changes that occur when warming, under high emissions scenario, stratospheric aerosol geoengineering. Notable...
Abstract. Stratospheric ozone and water vapour are key components of the Earth system, past future changes to both have important impacts on global regional climate. Here, we evaluate long-term in these species from pre-industrial period (1850) end 21st century Coupled Model Intercomparison Project phase 6 (CMIP6) models under a range emissions scenarios. There is good agreement between CMIP multi-model mean observations for total column (TCO), although there substantial variation individual...
Abstract. This paper quantifies the pre-industrial (1850) to present-day (2014) effective radiative forcing (ERF) of anthropogenic emissions NOX, volatile organic compounds (VOCs; including CO), SO2, NH3, black carbon, and concentrations methane, N2O ozone-depleting halocarbons, using CMIP6 models. Concentration emission changes reactive species can cause multiple in composition radiatively active species: tropospheric ozone, stratospheric water vapour, secondary inorganic aerosol, methane....
Abstract The January 2022 Hunga Tonga-Hunga Ha’apai volcanic eruption injected a relatively small amount of sulfur dioxide, but significantly more water into the stratosphere than previously seen in modern satellite record. Here we show that large resulted perturbations to stratospheric aerosol evolution. Our climate model simulation reproduces observed enhanced vapor at pressure levels ~30 hPa for three months. Compared with without injection, this additional source increases hydroxide,...
Hydrofluorocarbons, many of which contain a CF(3) group, are one the major substitutes for chlorofluorocarbons and halons that being phased out because they contribute to stratospheric ozone depletion. It is critical ensure groups do not cause significant The rate coefficients key reactions determine efficiency radical as catalyst loss in stratosphere have been measured used model calculate possible depletion ozone. From these results, it concluded potentials related presence group...
Abstract By injecting different amounts of SO 2 at multiple latitudes, the spatial pattern aerosol optical depth (AOD) can be partially controlled. This leads to ability influence climate response geoengineering with stratospheric aerosols, providing potential for design. We use simulations from fully coupled whole‐atmosphere chemistry model CESM1(WACCM) demonstrate that by appropriately combining injection just four locations, 30°S, 15°S, 15°N, and 30°N, then three degrees freedom AOD...
Abstract Injection of SO 2 into the stratosphere has been proposed as a method to, in part, counteract anthropogenic climate change. So far, most studies investigated injections at equator or region tropics. Here we use Community Earth System Model version 1 Whole Atmosphere Climate (CESM1(WACCM)) to explore impact continuous single grid point seven different latitudes and two altitudes on aerosol distribution climate. For each 14 locations, 3 constant emission rates were tested identify...
GaP films were grown on offcut Si(001) substrates using migration enhanced epitaxy nucleation followed by molecular beam epitaxy, with the intent of controlling and eliminating formation heterovalent (III-V/IV) nucleation-related defects—antiphase domains, stacking faults, microtwins. Analysis these via reflection high-energy electron diffraction, atomic force microscopy, both cross-sectional plan-view transmission microscopies indicate high-quality layers Si that portend a virtual substrate...
Abstract The Community Earth System Model 2 (CESM2) is the latest developed by National Center for Atmospheric Research in collaboration with university community and significantly advanced most components compared to its predecessor (CESM1). Here, CESM2's representation of large‐scale atmospheric circulation variability assessed. Further context providedthrough comparison CESM1 large ensemble other models from Coupled Intercomparison Project (CMIP5 CMIP6). This includes an assessment jet...
Abstract Radiative forcing (RF) time series for total ozone from 1850 up to the present day are calculated based on historical simulations of 10 climate models contributing Coupled Model Intercomparison Project Phase 6 (CMIP6). In addition, RF is fields prepared as an input CMIP6 without chemistry schemes and a chemical transport model simulation. A radiative kernel constructed used derive RF. The in 2010 (2005–2014) relative 0.35 W m −2 [0.08–0.61] (5–95% uncertainty range) with both...
Geoengineering with stratospheric sulfate aerosols can, to some extent, be designed achieve different climate objectives. Here we use the state-of-the-art Community Earth System Model, version 1, Whole Atmosphere Climate Model as its atmospheric component (CESM1(WACCM)), compare surface and effects of two geoengineering strategies. In one, SO2 is injected into tropical lower stratosphere at equator keep global mean temperature nearly constant under an RCP8.5 scenario, has been commonly...