A5009879317- Atmospheric Ozone and Climate
- Climate variability and models
- Atmospheric chemistry and aerosols
- Atmospheric and Environmental Gas Dynamics
- Ionosphere and magnetosphere dynamics
- Solar and Space Plasma Dynamics
- Tropical and Extratropical Cyclones Research
- Meteorological Phenomena and Simulations
- Atmospheric aerosols and clouds
- Geophysics and Gravity Measurements
- Arctic and Antarctic ice dynamics
- Ocean Waves and Remote Sensing
- Air Quality Monitoring and Forecasting
- Methane Hydrates and Related Phenomena
- Oceanographic and Atmospheric Processes
- Cryospheric studies and observations
- Fire effects on ecosystems
- Solar Radiation and Photovoltaics
- Water Quality Monitoring and Analysis
- Climate change and permafrost
- Geological Studies and Exploration
- Hydrology and Watershed Management Studies
- Island Studies and Pacific Affairs
- Stellar, planetary, and galactic studies
- Spaceflight effects on biology
NSF National Center for Atmospheric Research
2015-2024
National Oceanic and Atmospheric Administration
2024
Climate and Global Dynamics Laboratory
2018-2023
Lamont-Doherty Earth Observatory
2018
Columbia University
2018
University of Colorado Boulder
1990-2008
Atmospheric and Environmental Research
2003-2008
University of Colorado System
1990-2004
Previous studies have extensively investigated the impact of Arctic sea ice anomalies on midlatitude circulation and associated surface climate in winter. However, there is an ongoing scientific debate regarding whether how retreat results observed cold anomaly over adjacent continents. We present a robust "cold Siberia" pattern winter following loss Barents-Kara seas late autumn advanced atmospheric general model, with well-resolved stratosphere. Additional targeted experiments reveal that...
Abstract It is the purpose of this paper to provide a comprehensive documentation new NCAR (National Center for Atmospheric Research) version spectral element (SE) dynamical core as part Community Earth System Model (CESM2.0) release. This differs from previous releases SE in several ways. Most notably hybrid sigma vertical coordinate based on dry air mass, condensates are dynamically active thermodynamic and momentum equations (also referred condensate loading), continuous motion conserve...
A new configuration of the Community Earth System Model (CESM)/Community Atmosphere with full chemistry (CAM-chem) supporting capability horizontal mesh refinement through use spectral element (SE) dynamical core is developed and called CESM/CAM-chem-SE. Horizontal in CESM/CAM-chem-SE unique novel that pollutants such as ozone are accurately represented at human exposure relevant scales while also directly including global feedbacks. down to ∼14 km over conterminous US (CONUS) beginning...
© 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
Evidence of the solar cycle in stratospheric polar temperature rests on a connection to quasi-biennial oscillation (QBO) equatorial wind. New evidence reported here establishes mechanism for how signature follows from QBO, which itself is shown vary with cycle. Equatorial westerlies below 30 mb systematically activity, as do easterlies above mb. Changes their duration introduce systematic drift into QBO's phase relative winter months, when vortex sensitive Corresponding changes polar-night...
Abstract General circulation models display a wide range of future predicted changes in the Northern Hemisphere winter stratospheric polar vortex. The downward influence this uncertainty on troposphere has previously been inferred from regression analyses across and is thought to contribute model spread tropospheric change. Here we complement such with idealized experiments using one where different zonal-mean vortex are artificially imposed mimic extreme ends change simulated by phase 5...
Abstract The spectral element (SE) variable‐resolution (VR) mesh dynamical core is tested in developmental versions of the Community Earth System Model version 2 (CESM2). SE baroclinic wave, aquaplanet and full physics configurations to evaluate simulations against uniform high low‐resolution simulations. Different physical parameterization suites are also evaluated gauge their sensitivity resolution. Dry cases compare well high‐resolution tests. More recent atmospheric physics, including...
Abstract. Specified dynamics schemes are ubiquitous modeling tools for isolating the roles of and transport on chemical weather climate. They typically constrain circulation a chemistry–climate model to in reanalysis product through linear relaxation. However, recent studies suggest that these create divergence climate meridional between models do not accurately reproduce trends circulation. In this study we perform systematic assessment specified scheme Community Earth System Model version...
Abstract Model intercomparison studies often report a large spread in simulation results, but quantifying the causes of these differences is hindered by fact that several processes contribute to model simultaneously. Here we use Multi‐Scale Infrastructure for Chemistry and Aerosols (MUSICA) version 0 investigate resolution dependencies simulated chemical species, with focus on between global uniform grid regional refinement simulations same modeling framework. We construct two (ne30 [∼112...
The 2-day wave is a prominent feature of the middle and upper atmosphere, amplifying twice-yearly around solstice. Its period, structure, reproducibility have led to its association with gravest planetary normal mode zonal wavenumber 3, so-called Rossby-gravity mode. On other hand, amplification solstice has also baroclinic instability summer easterlies. To explore relationship between instability, calculations are performed linearized primitive equations that been generalized account for...
Abstract A series of idealized prescribed soil moisture experiments is performed with the atmosphere/land stand-alone configuration Community Earth System Model, version 1, in an effort to find sources predictability for high-impact stationary wave anomalies observed recent boreal summers. We arbitrarily prescribe water have a zero value at selected domains continental United States and run 100-member ensembles examine monthly seasonal mean response. Contrary lack substantial response...
Satellite measurements reveal the distribution of ozone column abundance to be complex and highly dynamic, with fluctuations as large 100% common in both hemispheres. Observations total from Nimbus 7 mapping spectrometer (TOMS) together contemporaneous analyses circulation are used investigate origin these fluctuations. A component variability is explained by quasi‐columnar motion air along isentropic surfaces lower stratosphere. The vertical such introduces anomalous through compression...
Interannual changes of stratospheric dynamical structure and ozone are explored in observed variations over the Northern Hemisphere during 1980s 1990s. Changes consistent with a strengthening weakening residual mean circulation stratosphere. It varies Eliassen–Palm (E–P) flux transmitted upward from troposphere and, to lesser degree, quasi-biennial oscillation (QBO). These two influences alone account for almost all interannual variance wintertime temperature decades, even unusually cold...
A three‐dimensional model of dynamics and photochemistry is used to investigate the influence planetary wave activity on seasonal evolution wintertime stratosphere, which dictates springtime conditions. The final warming ozone are each found depend strongly upon during disturbed season. integrations reproduce their observed dependence, enters through anomalous upward Eliassen‐Palm (EP) flux from troposphere equatorial wind associated with Quasi‐Biennial Oscillation (QBO). Of those major...
Abstract. It is the purpose of this paper to document NCAR global model topography generation software for unstructured grids (NCAR_Topo (v1.0)). Given a grid, computes fraction grid box covered by land, grid-box mean elevation (deviation from geoid that defines nominal sea level surface), and associated sub-grid-scale variances commonly used gravity wave turbulent mountain stress parameterizations. The supports regular latitude–longitude as well grids, e.g., icosahedral, Voronoi,...
The diurnal cycle present in many climate properties is undersampled asynoptic data, which, through aliasing, introduces a bias into time-mean behavior derived from satellite measurements. This source of systematic error investigated high-resolution Global Cloud Imagery (GCI), which provides proxy, with realistic space–time variability, for several to be observed space. GCI, resolves mesoscale and variability on global basis, sampled asynoptically according orbital viewing characteristics...
NCEP reanalyses are used to isolate systematic variations in the stratosphere that operated coherently over last four decades with 11-yr variation of UV irradiance. Only a small is visible at low frequency, which would reflect simple linear response drifts solar flux, Fs. However, manifests itself prominently high involves changes between neighboring years. Corresponding interannual variability, frequency reflects more complex, nonlinear It analogous similar found earlier quasi-biennial...
Records of analyzed dynamical structure indicate a correlation with the 11‐year variation solar flux F s . In monthly record, anomalous temperature maximizes in stratosphere, symmetry about equator. However, even there, signature is weak and scarcely significant. Sampling same record around solstice during extremal phases QBO sharply enhances strength, significance, signature. tropics follows from decadal modulation frequency quasi‐biennial oscillation (QBO). instantaneous power spectra...
Mesospheric inversions are studied in vertical soundings from the French lidar at Observatoire de Haute‐Provence and synoptic global structure that was observed simultaneously by UARS satellite. The latter provides instantaneous three‐dimensional (3‐D) of circulation accompanies mesospheric inversions. A numerical simulation with a 3‐D primitive equation model is then shown to reproduce major features behavior. Both reveal an extensive pattern inverted thermal structure. behavior closely...
Interannual variations in the tropical and polar stratosphere are investigated monthly mean records of north temperature equatorial zonal wind. The spectrum possesses discrete components associated with quasi‐biennial oscillation (QBO), as well a biennial (BO) that figures prominently record north‐polar temperature. BO, fact, accounts for much variance QBO. running correlation between wind oscillates on decadal timescale, resembling 11‐year sunspot cycle [ Kodera , 1993]. This is shown to...
Abstract Evidence of the solar cycle in stratospheric polar temperature rests on a connection to quasi-biennial oscillation (QBO) equatorial wind. New evidence reported here establishes mechanism for how signature follows from QBO, which itself is shown vary with cycle. Equatorial westerlies below 30 mb systematically activity, as do easterlies above mb. Changes their duration introduce systematic drift into QBO's phase relative winter months, when vortex sensitive Corresponding changes...
Abstract Interannual changes of the stratospheric circulation are studied in relation to coherent tropospheric circulation. Emerging over winter pole is a clear signature adiabatic warming and anomalous downwelling. Reflecting an intensification Brewer–Dobson circulation, downwelling extends from levels into troposphere. Compensating for it at subpolar latitudes cooling upwelling. Equally coherent, upwelling occupies same as Inside tropical troposphere, replaced by warming. It reflects...
Interannual changes of springtime ozone over the Arctic follow from anomalous transport and chemical depletion, two mechanisms that control wintertime increase ozone. Attempts to disentangle these contributions rest upon isolation air Arctic. To elucidate between warm cold winters, their latitude‐height structure is investigated in solar backscatterd ultraviolet record then related contemporaneous dynamical National Centers for Environmental Prediction record. Structural differences winters...
Integrations with the nonlinear primitive equations are used to study 3D diabatic structure underlying Brewer–Dobson circulation of middle atmosphere. Such reveals zonally asymmetric contributions mean downwelling over winter hemisphere. It is evaluate w* from mechanical dissipation planetary waves, associated irreversible eddy dispersion, and thermal heat transfer. Zonal-mean follows disproportionately those longitudes where air deflected across contours radiative equilibrium. This...
Thermal and humidity structures near the tropical tropopause are studied using microwave satellite retrievals of water vapor, along with contemporaneous dynamical structure in ECMWF analyses cold clouds high-resolution global cloud imagery. Examined during November 1991–February 1992, these fields all vary coherently outflow from convective centers—in upper troposphere as well lowermost stratosphere. The outbreak deep convection is accompanied by diabatic heating below a level between 250...