A5100613724- Climate variability and models
- Oceanographic and Atmospheric Processes
- Meteorological Phenomena and Simulations
- Atmospheric and Environmental Gas Dynamics
- Wind and Air Flow Studies
- Fluid Dynamics and Turbulent Flows
- Atmospheric chemistry and aerosols
- Atmospheric Ozone and Climate
- Tropical and Extratropical Cyclones Research
- Air Quality and Health Impacts
- Atmospheric aerosols and clouds
- Marine and coastal ecosystems
- Geophysics and Gravity Measurements
- Geology and Paleoclimatology Research
- Solar and Space Plasma Dynamics
- Particle Dynamics in Fluid Flows
- Arctic and Antarctic ice dynamics
- Ionosphere and magnetosphere dynamics
- Fluid Dynamics and Mixing
- Aerodynamics and Fluid Dynamics Research
- Characterization and Applications of Magnetic Nanoparticles
- Astro and Planetary Science
- Aerosol Filtration and Electrostatic Precipitation
- Heat Transfer and Optimization
- Force Microscopy Techniques and Applications
Zhejiang Zanyu Technology (China)
2023
Columbia University
2012-2022
Goddard Institute for Space Studies
2012-2022
Georgia Institute of Technology
2017-2021
Medgar Evers College
2019
City University of New York
2019
Earth Island Institute
2019
IIT@MIT
2005
Goddard Space Flight Center
1991
Abstract A full description of the ModelE version Goddard Institute for Space Studies (GISS) atmospheric general circulation model (GCM) and results are presented present-day climate simulations (ca. 1979). This is a complete rewrite previous models incorporating numerous improvements in basic physics, stratospheric circulation, forcing fields. Notable changes include following: top now above stratopause, number vertical layers has increased, new cloud microphysical scheme used, vegetation...
Abstract We present a description of the ModelE2 version Goddard Institute for Space Studies (GISS) General Circulation Model (GCM) and configurations used in simulations performed Coupled Intercomparison Project Phase 5 (CMIP5). use six variations related to treatment atmospheric composition, calculation aerosol indirect effects, ocean model component. Specifically, we test difference between models that have noninteractive where radiatively important aerosols ozone are prescribed from...
This paper describes the GISS-E2.1 contribution to Coupled Model Intercomparison Project, Phase 6 (CMIP6). model version differs from predecessor (GISS-E2) chiefly due parameterization improvements atmospheric and ocean components, while keeping resolution same. skill when compared modern era climatologies is significantly higher than in previous versions. Additionally, updates forcings have a material impact on results. In particular, there been specific representations of modes variability...
Ocean mixing processes have traditionally been formulated using one-point turbulence closure models, specifically the Mellor and Yamada (MY) which were pioneered in geophysics 1980 state-of-the-art modeling. These models widely applied over years, but underlying core physical assumptions hardly improved since 1980s; yet, meantime, modeling has made sufficient progress to allow four improvements be made. 1) The value of Ricr. MY-type yield a low for critical Richardson number, Ricr = 0.2 (the...
Second-order turbulence models of the Mellor and Yamada type have been widely used to simulate planetary boundary layer (PBL). It is, however, known that these several deficiencies. For example, assuming production turbulent kinetic energy equals its dissipation, they all predict a critical Richardson number is about four times smaller than large eddy simulation (LES) data in stably stratified flows are unable distinguish vertical lateral components neutral PBLs, height lower expected. In...
Abstract Observations of climate change during the CMIP5 extended historical period (1850–2012) are compared to trends simulated by six versions NASA Goddard Institute for Space Studies ModelE2 Earth System Model. The models constructed from three atmospheric general circulation model, distinguished their treatment composition and aerosol indirect effect, combined with two ocean models, HYCOM Russell. Forcings that perturb model described. Five‐member ensemble averages each simulate surface...
Abstract We examine the anthropogenically forced climate response for 21st century representative concentration pathway (RCP) emission scenarios and their extensions period 2101–2500. The experiments were performed with ModelE2, a new version of NASA Goddard Institute Space Sciences (GISS) coupled general circulation model that includes three different versions atmospheric composition components: noninteractive (NINT) prescribed tuned aerosol indirect effect (AIE), TCAD fully interactive...
Abstract Simulations of the CMIP6 historical period 1850–2014, characterized by emergence anthropogenic climate drivers like greenhouse gases, are presented for different configurations NASA Goddard Institute Space Studies (GISS) Earth System ModelE2.1. The GISS‐E2.1 ensembles more sensitive to gas forcing than their CMIP5 predecessors (GISS‐E2) but warm less during recent decades due a reduction that is attributed greater longwave opacity in pre‐industrial simulations. This results an...
Abstract This paper presents the response to anthropogenic forcing in GISS‐E2.1 climate models for 21st century Shared Socioeconomic Pathways emission scenarios within Coupled Model Intercomparison Project Phase 6 (CMIP6). The experiments were performed using an updated and improved version of NASA Goddard Institute Space Studies (GISS) coupled general circulation model that includes two different versions atmospheric composition: A non‐interactive (NINT) with prescribed composition a tuned...
A Reynolds stress–based model is used to derive algebraic expressions for the vertical diffusivities Kα(α = m, h, s) momentum, heat, and salt. The are expressed as KαRρN,Tϵ in terms of density ratio Rρ αs∂S/∂z(αT∂T/∂z)−1, Brunt–Väisälä frequency N2 −gρ−10∂ρ/∂z, Richardson number RiT N2/Σ2 (Σ shear), dissipation rate kinetic energy ϵ. valid both mixed layer (ML) below it. Here N computed everywhere using large-scale fields from an ocean general circulation while contributed by resolved...
Abstract Using the NASA Goddard Institute for Space Studies (GISS) climate model, it is shown that with proper choice of gravity wave momentum flux entering stratosphere and relatively fine vertical layering at least 500 m in upper troposphere‐lower (UTLS), a realistic stratospheric quasi‐biennial oscillation (QBO) modeled period, amplitude, structure down to tropopause levels. It furthermore specified controls QBO period whereas width phase speed spectrum amplitude. Fine required downward...
Abstract. Recent studies have shown that, in response to a surface warming, the marine tropical low-cloud cover (LCC) as observed by passive-sensor satellites substantially decreases, therefore generating smaller negative value of top-of-the-atmosphere (TOA) cloud radiative effect (CRE). Here we study LCC and CRE interannual changes sea temperature (SST) forcings GISS model E2 climate model, developmental version E3 12 other models, function their ability represent vertical structure SST...
The Smagorinsky–Lilly (SL) SGS model νt=(CSΔ)2S yields a constant CS=0.20–0.22 which is factor of 2 larger than what needed in LES calculations; addition, Deardorff and Hunt et al. suggested empirical corrections to the SL account for effects stratification shear. In this paper, we propose an that naturally includes shear (recovering two previous models) gives rise value CS∼0.11. three basic assumptions underlying are (1) Fickian approximation, b=−2νtS, where b Reynolds stress tensor S...
Abstract A large set of laboratory, direct numerical simulation (DNS), and eddy (LES) data indicates that in stably stratified flows turbulent mixing exists up to Ri ∼ O(100), meaning there is practically no Ri(cr). On the other hand, traditional local second-order closure (SOC) models entail a critical Ri(cr) O(1) above which turbulence ceases exist are therefore unable explain data. The authors suggest how modify recent SOC model Cheng et al. reproduce for arbitrary Ri.
Turbulent convection is inherently a nonlocal phenomenon and primary condition for successful treatment of the convective boundary layer reliable model nonlocality. In dynamic equations governing flux, turbulent kinetic energy, etc., nonlocality represented by third-order moments (TOMs). Since simplest form, so-called down gradient approximation (DGA), severely underestimates TOMs (up to an order magnitude), more physical needed. 1994, analytical was presented that derived directly from...
Abstract The standard approach to studying the planetary boundary layer (PBL) via turbulence models begins with first-moment equations for temperature, moisture, and mean velocity. These entail second-order moments that are solutions of dynamic equations, which in turn third-order moments, so on. How where terminate (close) has not been a generally agreed upon procedure variety differ precisely way they sequence. This can be viewed as bottom-up approach. In this paper, top-down is suggested,...
Abstract The response of cloud simulations to turbulence parameterizations is studied systematically using the GISS general circulation model (GCM) E2 employed in Intergovernmental Panel on Climate Change’s (IPCC) Fifth Assessment Report (AR5). Without parameterization, relative humidity (RH) and low cover peak unrealistically close surface; with dry convection or only local these two quantities improve their vertical structures, but transport water vapor still weak planetary boundary layers...
Abstract Strong correlations of O 3 ‐CH 2 O, ‐CO and CO‐CH were observed during the Deriving Information on Surface Conditions from Column Vertically Resolved Observations Relevant to Air Quality (DISCOVER‐AQ) aircraft experiment in July 2011 over Washington‐Baltimore area. The linear regression slopes ‐CO, do not vary significantly with time (11 a.m. 4 p.m.) or altitude boundary layer. These relationships are simulated well by a regional chemical transport model. Using tagged‐tracer...
A model is presented to compute the turbulent kinetic energy dissipation length scale lε in a stably stratified shear flow. The expression for derived from solving spectral balance equation energy. buoyancy spectrum entering such constructed using Lagrangian timescale with modifications due stratification. final result given algebraic form as function of Froude number Fr and flux Richardson Rf, = lε(Fr, Rf). predicts that Rf < Rfc, decreases stratification or shear; > which may occur...
Abstract Previous versions of GISS climate models have either used formulations Rayleigh drag to represent unresolved gravity wave interactions with the model-resolved flow or included a rather complicated treatment waves that, while being interactive, involved specification relatively large number parameters that were not well constrained by observations and also was computationally very expensive. Here, authors introduce simple efficient orographic nonorographic their interaction resolved...
Abstract Strong correlation between O 3 and CO was observed during the Deriving Information on Surface Conditions from Column Vertically Resolved Observations Relevant to Air Quality (DISCOVER‐AQ) aircraft experiment in July 2011 over Washington‐Baltimore area. The does not vary significantly with time or altitude boundary layer. observations are simulated well by a regional chemical transport model. We analyze model results understand factors contributing ‐CO regression slope, which has...
Abstract We formulate a new second-order closure turbulence model by employing recent for the pressure–temperature correlation at equation level. As result, we obtain heat flux equations that avoid long-standing issue of finite critical Richardson number. The new, structurally simpler improves on Mellor–Yamada and Galperin et al. models; key feature includes enhanced mixing under stable conditions facilitating agreement with observational, experimental, high-resolution numerical datasets....