A5079891701- Atmospheric aerosols and clouds
- Atmospheric chemistry and aerosols
- Atmospheric Ozone and Climate
- Atmospheric and Environmental Gas Dynamics
- Calibration and Measurement Techniques
- Air Quality and Health Impacts
- Air Quality Monitoring and Forecasting
- Radiative Heat Transfer Studies
- Remote Sensing in Agriculture
- Arctic and Antarctic ice dynamics
- Advanced Aircraft Design and Technologies
- Oil Spill Detection and Mitigation
- Solar Radiation and Photovoltaics
- Meteorological Phenomena and Simulations
- Aeolian processes and effects
- Fire effects on ecosystems
- Cryospheric studies and observations
- Space exploration and regulation
- Infrared Target Detection Methodologies
- Hydrocarbon exploration and reservoir analysis
- Analytical Chemistry and Sensors
- Advanced Fiber Optic Sensors
- Winter Sports Injuries and Performance
- Gestational Diabetes Research and Management
- Radio Wave Propagation Studies
Bay Area Environmental Research Institute
2016-2025
Ames Research Center
2015-2025
National Aeronautics and Space Administration
2020
NASA Research Park
2019
Oak Ridge Associated Universities
2014-2016
Laboratory for Atmospheric and Space Physics
2012-2015
University of California, San Diego
2014
Associated Universities, Inc.
2014
Environmental Institute
2014
University of Colorado Boulder
2012
Abstract. Southern Africa produces almost a third of the Earth's biomass burning (BB) aerosol particles, yet fate these particles and their influence on regional global climate is poorly understood. ORACLES (ObseRvations Aerosols above CLouds intEractionS) 5-year NASA EVS-2 (Earth Venture Suborbital-2) investigation with three intensive observation periods designed to study key atmospheric processes that determine impacts aerosols. During Hemisphere winter spring (June–October), reaching 3–5...
Abstract. The total effect of aerosols, both directly and on cloud properties, remains the biggest source uncertainty in anthropogenic radiative forcing climate. Correct characterization intensive aerosol optical particularly conditions where absorbing is present, a crucial factor quantifying these effects. southeast Atlantic Ocean (SEA), with seasonal biomass burning smoke plumes overlying mixing persistent stratocumulus deck, offers an excellent natural laboratory to make observations...
Abstract. Southern Africa produces almost a third of the Earth’s biomass burning (BB) aerosol particles, yet fate these particles and their influence on regional global climate is poorly understood. ORACLES (ObseRvations Aerosols above CLouds intEractionS) five-year NASA EVS-2 (Earth Venture Suborbital-2) investigation with three Intensive Observation Periods designed to study key atmospheric processes that determine impacts aerosols. During Hemisphere winter spring (June-October), reaching...
Abstract. In the southeast Atlantic, well-defined smoke plumes from Africa advect over marine boundary layer cloud decks; both are most extensive around September, when of resides in free troposphere. A framework is put forth for evaluating performance a range global and regional atmospheric composition models against observations made during NASA ORACLES (ObseRvations Aerosols above CLouds their intEractionS) airborne mission September 2016. strength comparison focus on spatial distribution...
Abstract. The southeast Atlantic (SEA) region is host to a climatologically significant biomass burning aerosol layer overlying marine stratocumulus. We present the first results of directly measured above-cloud optical depth (ACAOD) from recent ObseRvations Aerosols above CLouds and their intEractionS (ORACLES) airborne field campaign during August September 2016. In our analysis, we use data Spectrometers for Sky-Scanning Sun-Tracking Atmospheric Research (4STAR) instrument found an...
Abstract. In southern Africa, widespread agricultural fires produce substantial biomass burning (BB) emissions over the region. The seasonal smoke plumes associated with these are then advected westward persistent stratocumulus cloud deck in southeast Atlantic (SEA) Ocean, resulting aerosol effects which vary time and location. Much work has focused on of plumes, but previous studies have also described an elevated free tropospheric water vapor signal SEA. Water influences climate its own...
Abstract. All-sky direct aerosol radiative effects (DARE) play a significant yet still uncertain role in climate. This is partly due to poorly quantified properties of above clouds (AAC). We compute global estimates shortwave top-of-atmosphere DARE over opaque water (OWCs), DAREOWC, using observation-based and cloud from combination A-Train satellite sensors transfer model. There are three major differences between our DAREOWC calculations previous studies: (1) we use the depolarization...
Abstract. Marine stratocumulus cloud properties over the Southeast Atlantic Ocean are impacted by contact between above-cloud biomass burning aerosols and tops. Different vertical separations (0 to 2000 m) aerosol layer tops were observed on six research flights in September 2016 during NASA ObseRvations of Aerosols above CLouds their intEractionS (ORACLES) field campaign. There 30 profiles, where an with concentration (Na) > 500 cm−3 was within 100 m tops, 41 separated Na located more...
Abstract The southeast Atlantic has expansive aerosol plumes overlying clouds for a third of each year. Aerosol optical depths (AODs) were measured from the airborne Sun photometer and lidar during 2016 NASA ObseRvations Aerosols above CLouds their intEractionS (ORACLES) field campaign. We compare these measurements with one another collocated Moderate Resolution Imaging Spectroradiometer (MODIS) observations at native spatial resolutions using <15‐min 3‐h temporal collocation criteria....
Abstract. Aerosol heating due to shortwave absorption has implications for local atmospheric stability and regional dynamics. The derivation of rate profiles from space-based observations is challenging because it requires the vertical profile relevant properties such as aerosol extinction coefficient single-scattering albedo (SSA). In southeastern Atlantic, this challenge amplified by presence stratocumulus clouds below biomass burning plume advected Africa, since cloud affect magnitude...
Abstract. Determining the direct aerosol radiative effect (DARE) of absorbing aerosols above clouds from satellite observations alone is a challenging task, in part because signal layer not easily untangled that below. In this study, we use aircraft measurements NASA ObseRvations CLouds Aerosols and their intEractionS (ORACLES) project southeastern Atlantic to derive it with as few assumptions possible. This accomplished by using spectral irradiance (Solar Spectral Flux Radiometer, SSFR)...
Abstract. Biomass burning aerosols (BBA) from agricultural fires in southern Africa contribute about one-third of global carbonaceous aerosol load. These particles have strong radiative effects the southeast Atlantic (SEA), which depend on contrast between layer free troposphere (FT) and underlying cloud layer. However, there is large disagreements model estimates aerosol-driven climate forcing due to uncertainties vertical distribution, optical properties, lifecycle these particles. This...
Abstract. In this paper, we use observations from the NASA ORACLES (ObseRvations of CLouds above Aerosols and their intEractionS) aircraft campaign to develop a framework by way two parameterizations that establishes regionally representative relationships between aerosol-cloud properties radiative effects. These rely on new spectral aerosol property retrievals single scattering albedo (SSA) asymmetry parameter (ASY). The capture natural variability study region as sampled, both were found...
Abstract. The NASA ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) airborne field campaigns deployed a 4STAR (Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research) instrument onboard P-3 aircraft to measure columnar optical properties biomass burning aerosol smoke plumes over the Southeast Atlantic Ocean from 2016 2018. Although 4STAR’s retrievals direct solar irradiances diffuse sky radiances were performed, analyzed, compared against other via Single...
Abstract. A new retrieval scheme for cloud optical thickness, effective radius, and thermodynamic phase was developed ground-based measurements of shortwave solar spectral transmittance. Fifteen parameters were derived to quantify variations in transmittance due absorption scattering liquid water ice clouds, manifested by shifts slopes, curvatures, maxima, minima. To retrieve thickness particle a weighted least square fit that matched the modeled applied. The this analysis made with Solar...
Abstract The National Aeronautics and Space Administration (NASA)’s Arctic Radiation-IceBridge Sea Ice Experiment (ARISE) acquired unique aircraft data on atmospheric radiation sea ice properties during the critical late summer to autumn minimum commencement of refreezing. C-130 flew 15 missions over Beaufort between 4 24 September 2014. ARISE deployed a shortwave longwave broadband radiometer (BBR) system from Naval Research Laboratory; Solar Spectral Flux Radiometer (SSFR) University...
Abstract Industry advances have greatly reduced the cost and size of ground-based shortwave (SW) sensors for ultraviolet, visible, near-infrared spectral ranges that make up solar spectrum, while simultaneously increasing their ruggedness, reliability, calibration accuracy needed outdoor operation. These collocated meteorological equipment are an important part U.S. Department Energy (DOE) Atmospheric Radiation Measurement (ARM) User Facility, which has supported parallel integrated...
Abstract. This study develops the use of spectral total and diffuse irradiance measurements, made from a prototype hyperspectral total-diffuse sunshine pyranometer (SPN-S), to retrieve layer fine-mode aerosol (τaer) optical depths airborne platforms. Additionally, we analysis in an attempt partition depth into its τaer cirrus cloud (τcld) components absence coarse-mode aerosols. Two retrieval methods are developed: one leveraging information other using characteristics transmitted direct...
Aging and HIV are both risk factors for memory deficits declines in real-world functioning. However, we know little about the profile of driving instrumental activities daily living (IADL) across lifespan HIV. This study examined 145 younger (<50 years) 119 older (≥50 adults with who completed California Verbal Learning Test-Second Edition (CVLT-II), Wechsler Memory Scale-Third Logical subtest (WMS-III LM), a modified Lawton Brody ADL questionnaire. No predictors IADL dependence emerged...
Abstract. This study presents and evaluates an updated algorithm for quantification of absorbing aerosols above clouds (AACs) from passive satellite measurements. The focus is biomass burning in the south-eastern Atlantic Ocean during 2016 2017 ObseRvations Aerosols CLouds their intEractionS (ORACLES) field campaign deployments. retrieves above-cloud aerosol optical depth (AOD) underlying liquid cloud applied to measurements Sea-viewing Wide Field-of-view Sensor (SeaWiFS), Moderate...
Abstract. To help satellite retrieval of aerosols and studies their radiative effects, we demonstrate that daytime aerosol optical depth over low-level clouds is similar to in neighboring clear skies at the same heights. Based on recent airborne lidar sun photometer observations above southeast Atlantic, mean (AOD) difference 532 nm between 0 −0.01, when comparing cloudy sides, each up 20 km wide, cloud edges. The not statistically significant according a paired t test. Systematic...
Abstract A field campaign at Siple Dome in West Antarctica during the austral summer 2019/20 offers an opportunity to evaluate climate model performance, particularly cloud microphysical simulation. Over Antarctic ice sheets and shelves, clouds are a major regulator of surface energy balance, warm season their presence occasionally induces melt that can gradually weaken shelf structure. This dataset from Dome, obtained using transportable solar-powered equipment, includes balance...
Abstract The representation of Arctic surface radiative fluxes in atmospheric models and reanalyses is integral to understanding relevant physical processes, yet testing these confounded by a scarcity situ observations near‐surface state profiles, cloud vertical structure, phase, properties. Here, airborne measurements obtained from the Radiation IceBridge Sea&Ice Experiment (ARISE) during fall 2014 are compared with concurrent products Modern‐Era Retrospective analysis for Research...