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Full-Text Articles in Physics
The Consistent Behavior Of Tropical Rain: Average Reflectivity Vertical Profiles Determined By Rain Top Height, Reuven H. Heiblum, Ilan Koren, Orit Altaratz, Alexander Kostinski
The Consistent Behavior Of Tropical Rain: Average Reflectivity Vertical Profiles Determined By Rain Top Height, Reuven H. Heiblum, Ilan Koren, Orit Altaratz, Alexander Kostinski
Department of Physics Publications
Sixteen years of Tropical Rain Measuring Mission (TRMM) reflectivity profile data are collected for oceanic, continental, and island tropical regions within the boreal winter intertropical convergence zone (ITCZ). When sorted by the rain top height (RTH), a consistent behavior emerges where the average reflectivity profiles originating at different RTHs form non-overlapping manifolds in the height–reflectivity space, excluding the brightband regions for stratiform type profiles. Based on reflectivity slope (dBZ km−1) profile characteristics and physical considerations, the profiles are divided into three classes: 1) cold profiles, which originate above the −20°C isotherm height and display convergence to a …
Shape-Induced Gravitational Sorting Of Saharan Dust During Transatlantic Voyage: Evidence From Caliop Lidar Depolarization Measurements, Weidong Yang, Alexander Marshak, Alexander Kostinski, Tamás Várnai
Shape-Induced Gravitational Sorting Of Saharan Dust During Transatlantic Voyage: Evidence From Caliop Lidar Depolarization Measurements, Weidong Yang, Alexander Marshak, Alexander Kostinski, Tamás Várnai
Department of Physics Publications
Motivated by the physical picture of shape‐dependent air resistance and, consequently, shape‐induced differential sedimentation of dust particles, we searched for and found evidence of dust particle asphericity affecting the evolution and distribution of dust‐scattered light depolarization ratio (δ). Specifically, we examined a large data set of Cloud‐Aerosol Lidar with Orthogonal Polarization (CALIOP) observations of Saharan dust from June to August 2007. Observing along a typical transatlantic dust track, we find that (1) median δ is uniformly distributed between 2 and 5 km altitudes as the elevated dust leaves the west coast of Africa, thereby indicating uniformly random mixing of particle …
Effect Of Coarse Marine Aerosols On Stratocumulus Clouds, Yoav Lehahn, Ilan Koren, Orit Altaratz, Alexander Kostinski
Effect Of Coarse Marine Aerosols On Stratocumulus Clouds, Yoav Lehahn, Ilan Koren, Orit Altaratz, Alexander Kostinski
Department of Physics Publications
In contrast to fine anthropogenic aerosols (radii ∼μm), large aerosol particles are thought to enhance cloud droplet growth, promote precipitation formation and reduce cloud albedo. While shown in cloud simulation models, the impact of coarse aerosols on marine stratocumulus clouds lacks observational evidence. Here, by combining data from AMSR‐E and MODIS, both aboard NASA's satellite Aqua, we link the amount of coarse marine aerosols emitted to the atmosphere through wind‐driven processes with the size of cloud droplets, at the world's largest deck of marine stratocumulus clouds over the southeastern Pacific. For constrained meteorological conditions, approximately 1/2 of the change in …
Monitoring Automotive Particulate Matter Emissions With Lidar: A Review, Claudio Mazzoleni, Hampden D. Kuhns, Hans Moosmüller
Monitoring Automotive Particulate Matter Emissions With Lidar: A Review, Claudio Mazzoleni, Hampden D. Kuhns, Hans Moosmüller
Michigan Tech Publications
Automotive particulate matter (PM) causes deleterious effects on health and visibility. Physical and chemical properties of PM also influence climate change. Roadside remote sensing of automotive emissions is a valuable option for assessing the contribution of individual vehicles to the total PM burden. LiDAR represents a unique approach that allows measuring PM emissions from in-use vehicles with high sensitivity. This publication reviews vehicle emission remote sensing measurements using ultraviolet LiDAR and transmissometer systems. The paper discusses the measurement theory and documents examples of how these techniques provide a unique perspective for exhaust emissions of individual and groups of vehicles.