A5009714564- Oceanographic and Atmospheric Processes
- Meteorological Phenomena and Simulations
- Climate variability and models
- Tropical and Extratropical Cyclones Research
- Ocean Waves and Remote Sensing
- Atmospheric aerosols and clouds
- Marine and coastal ecosystems
- Geophysics and Gravity Measurements
- Fluid Dynamics and Turbulent Flows
- Atmospheric and Environmental Gas Dynamics
- Wind and Air Flow Studies
- Arctic and Antarctic ice dynamics
- Ionosphere and magnetosphere dynamics
- Aerospace and Aviation Technology
- Methane Hydrates and Related Phenomena
- Geology and Paleoclimatology Research
- Marine and fisheries research
- Cryospheric studies and observations
- Geological formations and processes
- Planetary Science and Exploration
- Geomagnetism and Paleomagnetism Studies
- Atmospheric Ozone and Climate
- Solar and Space Plasma Dynamics
- Precipitation Measurement and Analysis
- Seismic Waves and Analysis
University of Colorado Boulder
2014-2024
University of Colorado System
2000-2020
Kyoto University
2018
Istituto di Scienze Marine del Consiglio Nazionale delle Ricerche
2010-2016
NSF National Center for Atmospheric Research
2016
Institute of Structure of Matter
2010
National Research Council
2010
Cooperative Institute for Research in Environmental Sciences
2009
NOAA Oceanic and Atmospheric Research
1997-2004
Stennis Space Center
1989-1990
The Mellor-Yamada hierarchy of turbulent closure models is reexamined to show that the elimination a slight inconsistency in their analysis leads quasi-equilibrium model somewhat simpler than level 2½ model. Also need impose realizability conditions restricting dependence exchange coefficients on shearing rates eliminated. therefore more robust while principal advantage model, namely solution prognostic equation for kinetic energy retained. Its performance shown be not much different from 2½.
An improved mixed layer model, based on second‐moment closure of turbulence and suitable for application to oceanic atmospheric layers, is described. The model tested against observational data from different locations in the global oceans, including high latitudes tropics. belongs Mellor‐Yamada hierarchy but incorporates recent findings research large eddy simulations closure. modified expansion Galperin, Kantha, Hassid Rosati (1988) that leads a much simpler more robust quasi‐equilibrium...
An ice model, an ocean and a method of coupling the models are described. The model is synthesis, with variations extensions, previous modeling ideas. Ice thickness, concentration, velocity, internal energy prognostic variables. thermodynamics represented by temperatures at snow surface, interior, bottom surface. Melting freezing rates calculated ice‐atmosphere, ice‐ocean, atmosphere‐ocean interfaces. A prescribed portion summer meltwater can be stored on surface refrozen in fall. includes...
In this study, a coupled atmosphere–ocean wave modeling system is used to simulate air–sea interaction under high wind conditions. This made of three well-tested model components: The Pennsylvania State University–National Center for Atmospheric Research regional atmospheric Mesoscale Model, the University Colorado version Princeton Ocean and ocean surface gravity developed by Wave Model Development Implementation Group. initialized using 9-month spinup simulation forced 6-hourly stresses...
Turbulent entrainment at the density interface of a stable two-layer stratified fluid is studied in laboratory, constant surface stress being applied free surface. Conservation mass requires that overall Richardson number Ri = Dgδρ/ρu*2 each experiment, where D depth mixed layer, gδρ/ρ buoyancy difference and u* friction velocity. If rate E ue/u* function only Ri, it therefore experiment can be measured with greater accuracy than has previously been attained. The functional dependence on...
A persistent difficulty in modeling continental shelf and estuarine circulations is that associated with the correct specification of conditions on open boundaries. This paper deals application a new form radiation condition boundaries, which permits mean subtidal tidal forcing to be prescribed and, yet, allow transients generated inside region transmitted outwards. numerical model circulation formulated, using vertically integrated equations, accounts for transient wind forcing, as well...
Abstract Mixing in the free atmosphere above planetary boundary layer is of great importance to fate trace gases and pollutants. However, direct measurements turbulent dissipation rate by situ probes are very scarce radar fraught with uncertainties. In this paper, turbulence scaling concepts, developed over past decades for application oceanic mixing, used suggest an alternative technique retrieving properties from high-resolution soundings. This enables radiosondes, which have become quite...
The 2005 hurricane season set many new records, including the most named storms (26) and hurricanes in a (14). Of four that made landfall U.S., three (Katrina, Rita, Wilma) reached Category 5, struck Gulf Coast, inflicted severe damage loss of life. Hurricane Wilma had an observed sealevel center pressure 882 millibar (mbar) at its peak is strongest ever recorded Atlantic Ocean. Katrina damaged vast areas along Mississippi coast, flooded large parts New Orleans, destructive on record
The observed and predicted response of the bulk – skin sea surface temperature difference (δT) to changes in wind speed net heat flux is analyzed. Observations δT from northern Atlantic tropical Pacific Oceans demonstrate that affects through turbulent mixing. Increased winds typically increase flux, which increases size δT. At same time, increased cause enhanced mixing, decreases To predict change δT, both effects must be properly modeled. theoretical development existing models for traced...
In this first part of a two‐part paper we present results from high‐resolution, data‐assimilative, fully nonlinear barotropic tidal model the global oceans that excludes Arctic. The assimilates, in waters deeper than 1000 m, altimetric tides derived analysis 2 years TOPEX data. It also assimilates tide gage data coastal gages. domain includes covered by altimeter and extends to Antarctic. for primary semidiurnal (M , S N K ) diurnal (K 1 O P Q constituents. second deals with applications...
The Shigaraki unmanned aerial vehicle (UAV)-Radar Experiment (ShUREX) is an international (USA-Japan-France) observational campaign, whose overarching goal to demonstrate the utility of small, lightweight, inexpensive, autonomous UAVs in probing and monitoring lower troposphere promote synergistic use very high frequency (VHF) radars. 2-week campaign lasting from June 1 14, 2015, was carried out at Middle Upper Atmosphere (MU) Observatory Shigaraki, Japan. During DataHawk UAV, developed...
A Lagrangian analysis of the transport and dispersal plumes observed in satellite‐derived ocean color images was conducted using a data‐assimilating model Gulf Mexico. The interaction between pervasive cyclonic anticyclonic eddies generated advective paths that connect remote shelf regions. These aligned remarkably well with plume events recorded chlorophyll‐a product from SeaWiFS. Two such were studied. In one event material transported thin strip northern wall Loop Current an adjacent...
We describe here a nowcast/forecast system for the entire Mediterranean Sea, designed real‐time forecasts and closely resembling operational numerical weather prediction systems. The core of is high‐resolution (10 km) three‐dimensional primitive equation‐based, sigma‐coordinate circulation model, assimilating remotely sensed multi‐channel sea surface temperature in situ expendable bathythermograph/conductivity‐temperature‐depth observational data, using an optimal‐interpolational scheme....
We describe the application of a nowcast/forecast system for three‐dimensional currents, temperature, and salinity to Red Sea. The modeling is constructed around high‐resolution (6×7 km) primitive‐equation numerical circulation model with complete thermodynamics an imbedded turbulence closure submodel. It coupled near‐real‐time databases containing meteorological forecasts remotely sensed in situ temperature data. data are ingested into daily using nudged objective analysis technique....
Recent observations that include an airborne expendable bathythermograph (AXBT) survey and coincident satellite altimeter measurements together with a high‐resolution numerical simulation indicate the Laccadive High, anticyclonic circulating feature forms off SW coast of India during NE monsoon, is comprised multiple eddies. It hypothesized in addition to local remote seasonal forcing, High region influenced by intraseasonal signal originates Bay Bengal.
Long‐period lunar fortnightly (Mf) and monthly (Mm) tides in the global oceans are of particular interest to geophysicists because their impact on Earth's rotation, they oceanographers from point view response characteristics low‐frequency forcing. have long been quite controversial, but precision altimetry is providing an accurate means measuring modeling them oceans. Here we describe Mf Mm extracted a 1° barotropic hydrodynamic tidal model, which assimilates ocean estimated cycles 10–130...
Observations in the Greenland Sea marginal ice zone suggest that when strong stratification occurs near surface, momentum flux into internal wave field of upper ocean can be a major component force balance governs drift. Since energy is radiated away by waves, turbulent mixing and heat are also affected. We investigate downward waves an ice‐covered ocean, with idealized model comprising mixed layer overlying deep, uniformly stratified layer. A buoyancy jump separates from pycnocline. Drag...
Rotational effects on turbulence structure and mixing are investigated using a second-moment closure model. Both explicit implicit Coriolis terms considered. A general criterion for rotational to be small is established in of local turbulent Rossby numbers. Characteristic length scales determined Monin–Obukhov type similarity theory developed rotating stratified flows. one-dimensional version the model then applied simulate oceanic mixed layer evolution. It shown that rotation depth tend...
Abstract In the Bay of Bengal, warm, dry boreal spring concludes with onset summer monsoon and accompanying southwesterly winds, heavy rains, variable air–sea fluxes. Here, we summarize 2018 using observations collected through multinational Monsoon Intraseasonal Oscillations in Bengal (MISO-BoB) program between United States, India, Sri Lanka. MISO-BoB aims to improve understanding intraseasonal variability, field effort captured coupled response during a transition from active-to-break...
A two‐dimensional coupled ice‐ocean model has been formulated and applied to the wintertime Bering Sea marginal ice zone. The oceanic component is a multilevel that incorporates second‐moment closure for turbulent mixing in water column. cover modeled as viscous‐plastic continuum. Melting at interface computed using well‐known law‐of‐the‐wall concepts boundary layer, with particular attention disparate momentum scalar transfer resistance coefficients over rough walls. thermodynamic dynamical...
We tested models commonly used for estimating turbulence kinetic energy dissipation rates $$\varepsilon$$ from very high frequency stratosphere–troposphere radar data. These relate the root-mean-square value $$\sigma$$ of radial velocity fluctuations assessed Doppler spectra to . For this purpose, we data collected middle and upper atmosphere (MU) during Shigaraki unmanned aerial vehicle (UAV)—radar experiment campaigns carried out at MU Observatory, Japan, in June 2016 2017. On these...