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Wayne H. Slade
,
Emmanuel Boss
,
Giorgio Dall’Olmo
,
M. Rois Langner
,
James Loftin
,
Michael J. Behrenfeld
,
Collin Roesler
, and
Toby K. Westberry

optical absorption, attenuation, and backscattering coefficients. These quantities can be used to validate remotely sensed optical parameters and to estimate biomass and, using variable fluorescence, the physiological state of phytoplankton (e.g., Mueller et al. 2003 ; Behrenfeld and Boss 2003 ), as well as to provide constraints on particulate and dissolved pools and properties in ecosystem models (e.g., Fujii et al. 2007 ). Spectral particulate absorption and attenuation have also been used to

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Mary K. Butwin
,
Sibylle von Löwis
,
Melissa A. Pfeffer
,
Pavla Dagsson-Waldhauserova
,
Johann Thorsson
, and
Throstur Thorsteinsson

Dagsson-Waldhauserova 2019 ; Butwin et al. 2019 ). Both dust storms and resuspension of ash are defined here as particulate matter (PM) events ( Arnalds et al. 2013 ). PM is composed of any solid material suspended in the atmosphere. These particles can come from pollen, sea salt, smoke, dust, and volcanic ash ( AMS 2012 ). The length of time following an Icelandic eruption that PM events occur, that contain mostly resuspended ash as opposed to the bulk material available for dust storms, is

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Stuart A. Young
and
Mark A. Vaughan

level 2 data products from the lidar are the locations of atmospheric regions containing particulate matter (clouds and aerosols), the identification of these particles according to type, and profiles and layer integrals of particulate backscatter and extinction in these regions. This paper focuses on the fully automated retrieval of profiles of particulate backscatter and extinction. Note that the level 2 algorithms covered here are applied to measurements made by a single instrument (CALIOP

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Xugeng Cheng
,
Jane Liu
,
Tianliang Zhao
,
Xiaoning Xie
,
Zhixiong Chen
,
Zhengguo Shi
,
Xinzhou Li
,
Hong Wang
,
Mengmiao Yang
, and
Nanjun Tang

1. Introduction Fine particulate matter with aerodynamic diameter less than 2.5 μ m is referred to as PM 2.5 , which is a major air pollutant. In recent years, significant declines in PM 2.5 concentrations occurred nationwide in China, after the implementation of the toughest-ever clean air policy. Regions that suffer mostly from PM 2.5 pollution in China include the North China Plain (NCP), Yangtze River delta in eastern China (EC), and the Sichuan basin (SC). Surface PM 2

Open access
C. Hogrefe
,
W. Hao
,
K. Civerolo
,
J.-Y. Ku
,
G. Sistla
,
R. S. Gaza
,
L. Sedefian
,
K. Schere
,
A. Gilliland
, and
R. Mathur

1. Introduction Many U.S. air quality forecasting programs for ozone (O 3 ) and fine particulate matter (PM 2.5 ) operated by federal, state, and local agencies are based on a combination of weather prediction, statistical analysis, and expert judgment ( Gaza 1998 ; Ryan et al. 2000 ; Dye et al. 2000 ; U.S. EPA 2003a ). The application of grid-based photochemical modeling systems to provide real-time air quality forecasts has been a fairly recent development and has been mostly restricted to

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George Kallos
,
Marina Astitha
,
Petros Katsafados
, and
Chris Spyrou

of air pollutants released from Europe toward the eastern Mediterranean and North Africa ( Katsoulis and Whelpdale 1990 ; Luria et al. 1996 ; Kallos et al. 1997 , 1998a , b ; Millán et al. 1997 , 2005 ; Peleg et al. 1997 ; Gangoiti et al. 2001 ). Recent studies focus on the importance of long-range transport patterns of particulate matter (PM) of anthropogenic and natural origin as shown by Prospero et al. (2001) , Uno et al. (2001) , Rodriguez et al. (2001) , Bardouki et al. (2003

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P. Goswami
and
J. Baruah

1. Introduction The solid particles suspended in open air, such as soot generated by combustion, dust, and exhaust from automobiles, with diameters of 30 μ m (1 μ m = 0.00l mm) or less are called suspended particulate matter (SPM). Sources of SPM can be categorized according to the type of emissions: natural and manmade. Natural sources include plant pollen, wind blown dust, volcanic eruptions, and lightning-generated forest fires. Manmade sources include transportation vehicles, industrial

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Andrey Pleskachevsky
,
Mikhail Dobrynin
,
Alexander V. Babanin
,
Heinz Günther
, and
Emil Stanev

-designed circulation and ocean-wave models to simulate long time series of basic hydrodynamic and oceanographic parameters with fine spatial and temporal resolution. Imprecision of the model physics and parameterizations, however, can produce visible structural instability ( McWilliams 2007 ) and in particular an imbalance when modeling variables that are able to accumulate the model inaccuracy [e.g., suspended particulate matter (SPM)]. Assimilation of data from different sources can improve the model results (e

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E. R. Walker

614 JOURNAL OF APPLIED METEOROLOGY VoLU~m4A Particulate Diffusion Experiment~ E. R. W^~cER2Su.~dd Experimental Station, Ralston, Alberta, Canada(]~Ianuscript received 4 June 1965) Results am presented from a series of field experiments at Sufeld Experimental Station. In these experiments, glass spheres were released from a continuous elevated point source above gently rolling

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J. Rosinski
and
R. H. Snow

736JOURNAL OF METEOROLOGYVOLUME 18SECONDARY PARTICULATE MATTER FROM METEOR VAPORSJo Rosinski and R. H. SnowAmour Research Foundation, Chicago.(Manuscript received 15 March 1961)ABSTRACTThe size distribution of secondary particulate matter, formed from condensing vapors in meteoric trainsin the meteoric evaporating zone, was calculated. The diameters of the particles were found to be approximately proportional to the size of the meteor. The particles were calculated to be below 100 A in diameter

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