A5076884167- Atmospheric aerosols and clouds
- Atmospheric chemistry and aerosols
- Cryospheric studies and observations
- Meteorological Phenomena and Simulations
- Climate change and permafrost
- Atmospheric Ozone and Climate
- Climate variability and models
- Hydrology and Watershed Management Studies
- Arctic and Antarctic ice dynamics
- Aeolian processes and effects
- Polar Research and Ecology
- Atmospheric and Environmental Gas Dynamics
- Fire effects on ecosystems
- Ionosphere and magnetosphere dynamics
- Icing and De-icing Technologies
- Precipitation Measurement and Analysis
- Earthquake Detection and Analysis
- Air Quality Monitoring and Forecasting
- Geophysics and Gravity Measurements
- Landslides and related hazards
- Hydrological Forecasting Using AI
- Environmental Impact and Sustainability
- Solar Radiation and Photovoltaics
- Climate Change and Geoengineering
- Aerospace Engineering and Energy Systems
NSF National Center for Atmospheric Research
2010-2024
Research Applications (United States)
2010-2022
Research Applications Laboratory
2015-2022
Colorado State University
2008-2010
University of Wyoming
2004-2008
Knowledge of cloud and precipitation formation processes remains incomplete, yet global is predominantly produced by clouds containing the ice phase. Ice first forms in warmer than -36 °C on particles termed nuclei. We combine observations from field studies over a 14-year period, variety locations around globe, to show that concentrations nuclei active mixed-phase conditions can be related temperature number larger 0.5 μm diameter. This new relationship reduces unexplained variability at...
Abstract Aerosols influence cloud and precipitation development in complex ways due to myriad feedbacks at a variety of scales from individual clouds through entire storm systems. This paper describes the implementation, testing, results newly modified bulk microphysical parameterization with explicit droplet nucleation ice activation by aerosols. Idealized tests high-resolution, convection-permitting, continental-scale, 72-h simulation five sensitivity experiments showed that increased...
Abstract WRF-Solar is a specific configuration and augmentation of the Weather Research Forecasting (WRF) Model designed for solar energy applications. Recent upgrades to WRF contribute making model appropriate power forecasting comprise 1) developments diagnose internally relevant atmospheric parameters required by industry, 2) improved representation aerosol–radiation feedback, 3) incorporation cloud–aerosol interactions, 4) cloud–radiation feedback. The are presented together with...
Many soil‐derived particles dominated by insoluble material, including Saharan dusts, are known to act as ice nuclei. If, however, dust can compete with other atmospheric particle types form liquid cloud droplets, they have a greater potential change climate through indirect effects on radiative properties and affect the hydrological cycle precipitation changes. By directly collecting analyzing residual nuclei of small we demonstrate that do commonly condensation (CCN) in eastern North...
Abstract The initiation of ice in an isolated orographic wave cloud was compared with expectations based on nucleating aerosol concentrations and predictions from new nucleation parameterizations applied a parcel model. Measurements crystal number were found to be good agreement both measured nuclei feeding the clouds determined residual particles collected by counterflow virtual impactor. Using lognormal distributions fitted size chemical compositions, reasonably well predicted 1D model...
Abstract The 2020 wildfire season (May through December) in the United States was exceptionally active, with National Interagency Fire Center reporting over 10 million acres ( <?CDATA $\gt$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mo>></mml:mo> </mml:math> 40 000 km 2 ) burned. During September events, large concentrations of smoke particulates were emitted into atmosphere. As a result, responsible for ∼10%–30% reduction solar power production...
© 2024 American Meteorological Society. This published article is licensed under the terms of default AMS reuse license. For information regarding this content and general copyright information, consult Copyright Policy (www.ametsoc.org/PUBSReuseLicenses). Corresponding author: Francina Dominguez, francina@illinois.edu
A liquid‐phase Lagrangian parcel model was expanded to include nucleation and growth of ice crystals. Intercomparisons between three heterogeneous parameterizations that link aerosol type number crystal concentration were conducted. Results indicate large differences in the prediction formation modestly supercooled clouds susceptibility cirrus for same assumed distribution. Only one parameterization has an observational constraint limits maximum concentrations be a fraction total potential...
Abstract Aerosol‐cloud interactions (ACI) in warm clouds are the primary source of uncertainty effective radiative forcing (ERF) during historical period and, by extension, inferred climate sensitivity. The ERF due to ACI (ERFaci) is composed changes cloud microphysics and adjustments microphysics. Here, we examine processes that drive ERFaci using a perturbed parameter ensemble (PPE) hosted CAM6. Observational constraints on PPE result substantial response macrophysics anthropogenic...
Abstract. This paper documents the methodology and preliminary results from a perturbed parameter ensemble (PPE) technique, where multiple parameters are varied simultaneously values determined with Latin hypercube sampling. is done Community Atmosphere Model version 6 (CAM6), atmospheric component of Earth System 2 (CESM2). We apply PPE method to CESM2–CAM6 understand climate sensitivity physics parameters. The initial simulations vary 45 in microphysics, convection, turbulence aerosol...
Abstract. This paper documents the methodology and preliminary results from a Perturbed Parameter Ensemble (PPE) technique, where multiple parameters are varied simultaneously parameter values determined with Latin hypercube sampling. is done Community Atmosphere Model version 6 (CAM6), atmospheric component of Earth System 2 (CESM2). We apply PPE method to CESM2-CAM6 understand climate sensitivity physics parameters. The initial simulations vary 45 in microphysics, convection, turbulence...
Abstract The sensitivity of cloud feedbacks to atmospheric model parameters is evaluated using a CAM6 perturbed parameter ensemble (PPE). PPE perturbs 45 across 262 simulations, 206 which are used here. spread in the total feedback and its six components comparable CMIP6 AMIP ensembles, indicating that parametric uncertainty mirrors structural uncertainty. However, high-cloud altitude generally larger than WCRP assessment, CMIP6, values. We evaluate influence each on components. also explore...
ABSTRACT Glacier mass balance and runoff are simulated from 1955 to 2014 for the catchment (46% glacier cover) containing Chhota Shigri (Western Himalaya) using gridded data three regional climate models: (1) Rossby Centre atmospheric model v.4 (RCA4); (2) REgional atmosphere MOdel (REMO); (3) Weather Research Forecasting Model (WRF). The input downscaled simulation grid (300 m) calibrated with point measurements of temperature precipitation. Additional is daily potential global radiation...
Abstract. Detailed measurements of ice crystals in cirrus clouds were used to compare with results from the Community Atmospheric Model Version 5 (CAM5) global climate model. The observations are two different field campaigns contrasting conditions: Radiation Measurements Spring Cloud Intensive Operational Period 2000 (ARM-IOP), which was characterized primarily by midlatitude frontal and cirrus, Tropical Composition, Climate Coupling (TC4), dominated anvil cirrus. Results show that model...
Abstract This paper describes a new approach for representing ice microphysics in climate models. In contrast with most previous schemes, this does not include separate categories cloud and precipitating instead uses single two-moment category to represent all solid hydrometeors. Thus, there is no need an “autoconversion” size threshold parameter, which has critical impact on simulated the Community Atmosphere Model (CAM5) yet poorly constrained by theory or observations. Further, treatment,...
Abstract. Aerosol–cloud interactions (ACIs) are the largest source of uncertainty in inferring magnitude future warming consistent with observational record. The effective radiative forcing due to ACI (ERFaci) is dominated by liquid clouds and composed two terms: change cloud albedo redistributing over a larger number droplets (Nd) macrophysical properties changes microphysics. These terms are, respectively, referred as (RFaci) aerosol–cloud adjustments. While RFaci uncertain, its sign...
Abstract We present a new additive method, referred to as sage for Simplified Additive Gaussian processes Emulator, emulating climate model Perturbed Parameter Ensembles (PPEs). estimates the value of output sum terms. Each term is mean Process, and corresponds impact parameter or group on variable interest. This design caters sparsity PPEs, which are characterized by limited ensemble members high dimensionality space raise issue sensitivity in emulator design. quantifies variability...
Abstract. Variations in the chemical composition of atmospheric aerosols alter their hygroscopicity and can lead to changes cloud-active fraction aerosols, or cloud condensation nuclei (CCN) number concentration. To investigate importance this effect under different conditions, droplet formation was simulated with a Lagrangian parcel model. Initial values updraft speed temperature were systematically varied along aerosol concentration, size (represented by parameter, κ). A previous study...
We use the WRF system to study impacts of biomass burning smoke from Central America on several tornado outbreaks occurring in US during spring. The model is configured with an aerosol-aware microphysics parameterization capable resolving aerosol-cloud-radiation interactions a cost-efficient way for numerical weather prediction (NWP) applications. Primary aerosol emissions are included and constrained using inverse modeling technique satellite-based AOD observations. Simulations turning off...
Abstract A Perturbed Parameter Ensemble (PPE) with the Community Atmosphere Model version 6 (CAM6) is used to better understand sensitivity of aerosol forcing and cloud feedbacks changes in model processes. Aerosol through aerosol‐cloud interactions mostly negative (a cooling) due shortwave radiation, while are positive or different regions contrasting longwave effects. Both related mean climate state. Higher magnitude radiative effects generally larger net feedback. broadly susceptibility...
ABSTRACT Meltwater runoff in the catchment area containing Chhota Shigri glacier (Western Himalaya) is simulated for period 1951–2099. The applied mass-balance model forced by downscaled products from four regional climate models with different horizontal resolution. For future scenarios we use high resolution time series of 5 km grid spacing, generated using newly developed Intermediate Complexity Atmospheric Research Model. meteorological input to 300 m an ice flow provides annually...
A twin angle optical particle counter (TAOPC) that measures forward scattering at 40° and 74° was developed to determine the index of refraction atmospheric particles. An error analysis indicates measurement uncertainties for size are between 4 10% particles >1.5 μ m 5 15% 74°. For determination, lead 1 2.5%. The instrument tested on nonabsorbing spherical known composition in laboratory. majority estimated indices were within ±1% expected indices, determination acceptable error. also...
Abstract Orographic precipitation depends on the environmental conditions and barrier shape. In this study we examine sensitivity of efficiency (i.e., drying ratio ( DR )), defined as to incoming water flux, mountain shape, temperature, stability, horizontal velocity air mass. Furthermore, explore how Colorado ranges might change under warmer moister in future. For given conditions, find be primarily dependent upwind slope for wider than about 70 km both width narrower ranges. Temperature is...