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Full-Text Articles in Physics
Calipso Observations Of Transatlantic Dust: Vertical Stratification And Effect Of Clouds, W. Yang, A. Marshak, T. Varnai, O. V. Kalashnikova, A. Kostinski
Calipso Observations Of Transatlantic Dust: Vertical Stratification And Effect Of Clouds, W. Yang, A. Marshak, T. Varnai, O. V. Kalashnikova, A. Kostinski
Department of Physics Publications
We use CALIOP nighttime measurements of lidar backscatter, color and depolarization ratios, as well as particulate retrievals during the summer of 2007 to study transatlantic dust properties downwind of Saharan sources, and to examine the influence of nearby clouds on dust. Our analysis suggests that (1) under clear skies, while lidar backscatter and color ratio do not change much with altitude and longitude in the Saharan Air Layer (SAL), depolarization ratio increases with altitude and decreases westward in the SAL; (2) the vertical lapse rate of dust depolarization ratio, introduced here, increases within SAL as plumes move westward; (3) nearby …
Molecule For Electronics: A Myriad Of Opportunities Comes With Daunting Challenges, Ranjit Pati
Molecule For Electronics: A Myriad Of Opportunities Comes With Daunting Challenges, Ranjit Pati
Department of Physics Publications
Since the invention of Integrated Circuit (IC) in 1958, we have seen an unprecedented growth in Si-based electronics industry; ICs are currently used in almost all electronic gadgets. However, it is now very much clear that this era of growth we have been witnessing for the last five decades will soon hit the brick wall, once the transistor size reaches the physical limit of miniaturization.
Measurements Of Ice Nucleation By Mineral Dusts In The Contact Mode, Kristopher W. Bunker, Swarup China, C. Mazzoleni, A. B. Kostinski, Will Cantrell
Measurements Of Ice Nucleation By Mineral Dusts In The Contact Mode, Kristopher W. Bunker, Swarup China, C. Mazzoleni, A. B. Kostinski, Will Cantrell
Department of Physics Publications
Formation of ice in Earth's atmosphere at temperatures above approximately −20 °C is one of the outstanding problems in cloud physics. Contact nucleation has been suggested as a possible mechanism for freezing at relatively high temperatures; some laboratory experiments have shown contact freezing activity at temperatures as high as −4 °C. We have investigated Arizona Test Dust and kaolinite as contact nuclei as a function of size and temperature and find that the fraction of submicron particles that are active as contact ice nuclei is less than 10−3 for −18 °C and greater. We also find that the different dusts …
Absorbing Aerosols At High Relative Humidity: Linking Hygroscopic Growth To Optical Properties, J. Michel Flores, R. Z. Bar-Or, N Bluvshtein, A. Abo-Riziq, A. B. Kostinski, S. Borrmann, Ilan Koren, Y Rudich
Absorbing Aerosols At High Relative Humidity: Linking Hygroscopic Growth To Optical Properties, J. Michel Flores, R. Z. Bar-Or, N Bluvshtein, A. Abo-Riziq, A. B. Kostinski, S. Borrmann, Ilan Koren, Y Rudich
Department of Physics Publications
One of the major uncertainties in the understanding of Earth's climate system is the interaction between solar radiation and aerosols in the atmosphere. Aerosols exposed to high humidity will change their chemical, physical, and optical properties due to their increased water content. To model hydrated aerosols, atmospheric chemistry and climate models often use the volume weighted mixing rule to predict the complex refractive index (RI) of aerosols when they interact with high relative humidity, and, in general, assume homogeneous mixing. This study explores the validity of these assumptions. A humidified cavity ring down aerosol spectrometer (CRD-AS) and a tandem hygroscopic …
Bounds On Spectral Dispersion From Fermi-Detected Gamma Ray Bursts, Robert J. Nemiroff, Ryan Connolly, Justin Holmes, Alexander Kostinski
Bounds On Spectral Dispersion From Fermi-Detected Gamma Ray Bursts, Robert J. Nemiroff, Ryan Connolly, Justin Holmes, Alexander Kostinski
Department of Physics Publications
Data from four Fermi-detected gamma-ray bursts (GRBs) are used to set limits on spectral dispersion of electromagnetic radiation across the Universe. The analysis focuses on photons recorded above 1 GeV for Fermi-detected GRB 080916C, GRB 090510A, GRB 090902B, and GRB 090926A because these high-energy photons yield the tightest bounds on light dispersion. It is shown that significant photon bunches in GRB 090510A, possibly classic GRB pulses, are remarkably brief, an order of magnitude shorter in duration than any previously claimed temporal feature in this energy range. Although conceivably a>3σ fluctuation, when taken at face value, these pulses lead to …
Discernible Rhythm In The Spatio/Temporal Distributions Of Transatlantic Dust, Y. Ben-Ami, I. Koren, O. Altaratz, A. B. Kostinski, Y. Lehahn
Discernible Rhythm In The Spatio/Temporal Distributions Of Transatlantic Dust, Y. Ben-Ami, I. Koren, O. Altaratz, A. B. Kostinski, Y. Lehahn
Department of Physics Publications
The differences in North African dust emission regions and transport routes, between the boreal winter and summer, are thoroughly documented. Here we re-examine the spatial and temporal characteristics of dust transport over the tropical and subtropical North Atlantic Ocean, using 10 yr of satellite data, in order to better characterize the different dust transport periods. We see a robust annual triplet: a discernible rhythm of "transatlantic dust weather".
The proposed annual partition is composed of two heavy loading periods, associated here with a northern-route period and southern-route period, and one light-loading period, accompanied by unusually low average optical depth of …
Observational Bounds On Atmospheric Heating By Aerosol Absorption: Radiative Signature Of Transatlantic Dust, Amit Davidi, Alexander Kostinski, Ilan Koren, Yoav Lehahn
Observational Bounds On Atmospheric Heating By Aerosol Absorption: Radiative Signature Of Transatlantic Dust, Amit Davidi, Alexander Kostinski, Ilan Koren, Yoav Lehahn
Department of Physics Publications
[1] Aerosols absorb solar radiation thus changing the atmospheric temperature profile but the overall magnitude of this effect is not known. To that end, Saharan dust emissions over the Atlantic Ocean provide an opportunity to examine aerosol‐related heating via satellite imaging. A major difficulty, however, is disentangling a straightforward heating signal caused by the absorbing dust from a meteorological signal, which originates from correlation between dust concentration and air temperature. To tackle the problem, we combine temperature (T) soundings, from the atmospheric infrared sounder (AIRS), with aerosol optical depth (τ) measurements, from the moderate resolution imaging …