A5083311805- Atmospheric chemistry and aerosols
- Atmospheric and Environmental Gas Dynamics
- Atmospheric Ozone and Climate
- Oceanographic and Atmospheric Processes
- Atmospheric aerosols and clouds
- Ocean Waves and Remote Sensing
- Arctic and Antarctic ice dynamics
- Marine and coastal ecosystems
- Ocean Acidification Effects and Responses
- Air Quality and Health Impacts
- Meteorological Phenomena and Simulations
- Climate variability and models
- Methane Hydrates and Related Phenomena
- Oil Spill Detection and Mitigation
- Coastal and Marine Dynamics
- Tropical and Extratropical Cyclones Research
- Cryospheric studies and observations
- Mercury impact and mitigation studies
- Air Quality Monitoring and Forecasting
- Maritime Transport Emissions and Efficiency
- Odor and Emission Control Technologies
- Wind and Air Flow Studies
- Geological Studies and Exploration
- Isotope Analysis in Ecology
- Spectroscopy and Laser Applications
NOAA Physical Sciences Laboratory
2018-2025
University of Colorado Boulder
2016-2025
Cooperative Institute for Research in Environmental Sciences
2016-2025
National Oceanic and Atmospheric Administration
2015-2025
University of Colorado System
2015-2021
NOAA Earth System Research Laboratory
2016-2020
Physical Sciences (United States)
2017-2020
University of Notre Dame
2015-2017
Plymouth Marine Laboratory
2009-2016
University of Hawaii System
2001-2014
With the Arctic rapidly changing, needs to observe, understand, and model changes are essential. To support these needs, an annual cycle of observations atmospheric properties, processes, interactions were made while drifting with sea ice across central during Multidisciplinary Observatory for Study Climate (MOSAiC) expedition from October 2019 September 2020. An international team designed implemented comprehensive program document characterize all aspects system in unprecedented detail,...
The Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) was a yearlong expedition supported by icebreaker R/V Polarstern, following Transpolar Drift from October 2019 to 2020. campaign documented an annual cycle physical, biological, and chemical processes impacting atmosphere-ice-ocean system. Of central importance were measurements thermodynamic dynamic evolution sea ice. A multi-agency international team led University Colorado/CIRES NOAA-PSL observed...
The second Dynamics and Chemistry of Marine Stratocumulus (DYCOMS-II) field study is described. program consisted nine flights in marine stratocumulus west-southwest San Diego, California. objective the was to better understand physics a n d dynamics stratocumulus. Toward this end special flight strategies, including predominantly nocturnal flights, were employed optimize estimates entrainment velocities at cloud-top, large-scale divergence within boundary layer, drizzle processes cloud,...
Oceanic dimethylsulfide (DMS) emissions to the atmosphere are potentially important Earth's radiative balance. Since these driven by surface seawater concentration of DMS, it is understand processes controlling cycling sulfur in seawater. During third Pacific Sulfur/Stratus Investigation (PSI‐3, April 1991) we measured major reservoirs (total organic sulfur, total low molecular weight ester sulfate, protein dimethylsulfoniopropionate (DMSP), dimethylsulfoxide) and quantified many that cycle...
Abstract Emerging application areas such as air pollution in megacities, wind energy, urban security, and operation of unmanned aerial vehicles have intensified scientific societal interest mountain meteorology. To address needs help improve the prediction weather, U.S. Department Defense has funded a research effort—the Mountain Terrain Atmospheric Modeling Observations (MATERHORN) Program—that draws expertise multidisciplinary, multi-institutional, multinational group researchers. The...
Abstract The Coupled Air–Sea Processes and Electromagnetic Ducting Research (CASPER) project aims to better quantify atmospheric effects on the propagation of radar communication signals in marine environment. Such are associated with vertical gradients temperature water vapor surface layer (MASL) capping inversion boundary (MABL), as well horizontal variations these gradients. CASPER field measurements emphasized simultaneous characterization electromagnetic (EM) wave propagation,...
Abstract A variety of physical mechanisms are jointly responsible for facilitating air‐sea gas transfer through turbulent processes at the atmosphere‐ocean interface. The nature and relative importance these evolves with increasing wind speed. Theoretical modeling approaches advancing, but limited quantity observational data high speeds hinders assessment efforts. HiWinGS project successfully measured coefficients ( k 660 ) coincident wave statistics under conditions hourly mean up to 24 m s...
Abstract. We present air–sea fluxes of oxygenated volatile organics compounds (OVOCs) quantified by eddy covariance (EC) during the Atlantic Meridional Transect cruise in 2012. Measurements acetone, acetaldehyde, and methanol air as well water were made several different oceanic provinces over a wide range wind speeds (1–18 m s−1). The ocean appears to be net sink for acetone higher latitudes North but source subtropics. In South Atlantic, seawater was near saturation relative atmosphere,...
The rapid melt of snow and sea ice during the Arctic summer provides a significant source low-salinity meltwater to surface ocean on local scale. accumulation this on, under, around floes can result in relatively thin layers upper ocean. Due small-scale nature these upper-ocean features, typically order 1 m thick or less, they are rarely detected by standard methods, but nevertheless pervasive critically important summer. Observations Multidisciplinary drifting Observatory for Study Climate...
Abstract Fog constitutes a thick, opaque blanket of air hugging the Earth’s surface, laden with small water droplets or ice crystals. disrupts transportation, poses security threats, disorients human perception and impacts communications ecosystems. Collusion atmospheric, terrestrial hydrologic processes produces fog that pullulate over hygroscopic aerosols act as condensation nuclei. Marine is particularly complex, since underlying dynamic, thermodynamic (bio)physicochemical span fifteen...
Abstract The first research flight of the second Dynamics and Chemistry Marine Stratocumulus field study is analysed. This case attracted our interest because it showed a consistently deepening cloud layer despite macroscopic conditions which previous work has suggested should be an indication thinning or breakup. Detailed analysis data shows that cloud‐top entrainment instability parameter being well beyond its critical value did indeed deepen through night. Our best estimates show little...
Abstract Fast measurements of three scalars, ozone, dimethyl sulfide (DMS), and total water, are used to investigate the entrainment process in stratocumulus-topped boundary layer (STBL) observed over eastern subtropical Pacific during second Dynamics Chemistry Marine Stratocumulus Experiment (DYCOMS-II). Direct measurement flux profiles by eddy covariance is estimate velocity, average rate at which grows diabatically via incorporation overlying free tropospheric air. The velocities course...
We report the successful eddy‐correlation (EC) measurement of dimethyl sulfide (DMS) fluxes using an atmospheric pressure ionization mass spectrometer (APIMS). Calculated hourly transfer velocities span range two widely used parameterizations. The results suggest that factors in addition to wind speed also control flux, but some scatter each interval is no doubt due uncertainties. can at last measure flux a marine biogenic gas on time scale tens minutes, with accuracy percent. This enables...
[1] Updates for the Coupled Ocean-Atmosphere Response Experiment (COARE) physically based meteorological and gas transfer bulk flux algorithms are examined. The current versions summarized a generalization of codes to 79 gases is described. version COARE3.0 was compared with collection 26,700 covariance observations drag heat coefficients (compiled from three independent research groups). algorithm agreed on average within 5% wind speed range 2 18 m s−1. Covariance CO2 dimethyl sulfide (DMS)...
During the 2007 UK SOLAS Deep Ocean Gas Exchange Experiment in northeast Atlantic Ocean, we conducted first ever study of effect a deliberately released surfactant (oleyl alcohol) on gas transfer velocities ( k w ) open ocean. rates were estimated with 3 He/SF 6 dual tracer technique and from measured sea‐to‐air DMS fluxes surface water concentrations. A total seven estimates derived made, two which deemed to be influenced by surfactant. These exhibited suppression ∼5% 55% at intermediate...
[1] In the Southern Ocean Gas Exchange Experiment (SO GasEx), we measured an atmospheric dimethylsulfide (DMS) concentration of 118 ± 54 pptv (1σ), a DMS sea-to-air flux 2.9 2.1 μmol m−2 d−1 by eddy covariance, and seawater 1.6 0.7 nM. Dividing concurrent air-sea difference yields transfer velocity (kDMS). The kDMS in was significantly lower than previous measurements equatorial east Pacific, Sargasso Sea, northeast Atlantic, southeast Pacific. Normalizing for temperature dependence...
In the troposphere, methanol (CH3OH) is present ubiquitously and second in abundance among organic gases after methane. surface ocean, represents a supply of energy carbon for marine microbes. Here we report direct measurements air-sea transfer along ∼10,000-km north-south transect Atlantic. The flux was consistently from atmosphere to ocean. Constrained by aerodynamic limit measured rate sensible heat exchange, resembles one-way depositional process, which suggests dissolved concentrations...
Abstract We report simultaneous, underway eddy covariance measurements of the vertical flux isoprene, total monoterpenes, and dimethyl sulfide (DMS) over Northern Atlantic Ocean during fall. Mean isoprene monoterpene sea‐to‐air fluxes were significantly lower than mean DMS fluxes. While rare, intense observed, coincident with elevated mixing ratios. A statistically significant correlation between short wave radiation was not suggesting that photochemical processes in surface microlayer did...
Abstract Concurrent wavefield and turbulent flux measurements acquired during the Southern Ocean (SO) Gas Exchange (GasEx) High Wind Speed Study (HiWinGS) projects permit evaluation of dependence whitecap coverage W on wind speed, wave age, steepness, mean square slope, wind-wave breaking Reynolds numbers. The was determined from over 600 high-frequency visible imagery recordings 20 min each. Wave statistics were computed in situ remotely sensed data as well a WAVEWATCH III hindcast. first...
Abstract Predicting future climate hinges on our understanding of and ability to quantify air‐sea gas transfer. The latter relies parameterizations the transfer velocity k , which represents physical mass mechanisms is usually parameterized as a nonlinear function wind forcing. In an attempt reduce uncertainties in this study explores empirical that incorporate both speed sea state dependence via wave‐wind breaking Reynolds numbers, R H B . Analysis concurrent eddy covariance measured...
Abstract Unlike bromine, the effect of iodine chemistry on Arctic surface ozone budget is poorly constrained. We present ship-based measurements halogen oxides in high boundary layer from sunlit period March to October 2020 and show that enhances springtime tropospheric depletion. find chemical reactions between are second highest contributor loss over study period, after photolysis-initiated ahead bromine.
The air-sea gas transfer velocity ( K 660 ) is typically assessed as a function of the 10-m neutral wind speed U 10n ), but there remains substantial uncertainty in this relationship. Here CO 2 derived with eddy covariance (EC) technique from eight datasets (11 research cruises) are reevaluated consistent consideration solubility and Schmidt number inclusion ocean cool skin effect. shows an approximately linear dependence friction u * moderate winds, overall relative standard deviation...