scholarly journals Analysis of aerosol composition data for western United States wildfires between 2005 and 2015: Dust emissions, chloride depletion, and most enhanced aerosol constituents

2017 ◽  
Vol 122 (16) ◽  
pp. 8951-8966 ◽  
Author(s):  
Joseph S. Schlosser ◽  
Rachel A. Braun ◽  
Trevor Bradley ◽  
Hossein Dadashazar ◽  
Alexander B. MacDonald ◽  
...  
Keyword(s):  
United States ◽  
Western United States ◽  
Aerosol Composition ◽  
Dust Emissions ◽  
Composition Data ◽  
Chloride Depletion

scholarly journals Model evaluation of NO<sub>3</sub> secondary organic aerosol (SOA) source and heterogeneous organic aerosol (OA) sink in the Western United States

2012 ◽  
Vol 12 (2) ◽  
pp. 5189-5223 ◽  
Author(s):  
J. L. Fry ◽  
K. Sackinger
Keyword(s):  
United States ◽  
Secondary Organic Aerosol ◽  
Organic Aerosol ◽  
Chemical Mechanism ◽  
Western United States ◽  
Urban Centers ◽  
Aerosol Composition ◽  
Organic Gases ◽  
Source And Sink ◽  
Loss Rates

Abstract. The relative importance of NO3-initiated source and heterogeneous sink of organic aerosol in the Western United States is investigated using the WRF/Chem regional weather and chemistry model. The model is run for the four individual months, representing the four seasons, of January, May, August, and October, to produce hourly spatial maps of surface concentrations of NO3, organic aerosol (OA), and reactive organic gases (ROG, a sum of alkene species tracked in the lumped chemical mechanism employed). These "baseline" simulations are used in conjunction with literature data on secondary organic aerosol (SOA) mass yields, average organic aerosol composition, and reactive uptake coefficients for NO3 on organic surfaces to predict SOA source and OA heterogeneous loss rates due to reactions initiated by NO3. We find both source and sink rates maximized downwind of urban centers, therefore with a varying location that depends on wind direction. Both source and sink terms are maximum in summer, and SOA source dominates over OA loss by approximately three orders of magnitude, with large day-to-day variability. The NO3 source of SOA is found to be atmospherically significant (peak production rates of 0.4–3.0 μg kg−1 h−1), while the heterogeneous sink of OA via NO3 surface reactions (peak loss rates of 0.11–2.3 × 10−3 μg kg−1 h−1) is likely too small to significantly impact the atmospheric lifetime of either organic aerosol or oxidized nitrogen (NOy).

scholarly journals Model investigation of NO<sub>3</sub> secondary organic aerosol (SOA) source and heterogeneous organic aerosol (OA) sink in the western United States

2012 ◽  
Vol 12 (18) ◽  
pp. 8797-8811 ◽  
Author(s):  
J. L. Fry ◽  
K. Sackinger
Keyword(s):  
United States ◽  
Secondary Organic Aerosol ◽  
Organic Aerosol ◽  
Chemical Mechanism ◽  
Western United States ◽  
Urban Centers ◽  
Aerosol Composition ◽  
Organic Gases ◽  
Source And Sink ◽  
Loss Rates

Abstract. The relative importance of NO3-initiated source and heterogeneous sink of organic aerosol in the western United States is investigated using the WRF/Chem regional weather and chemistry model. The model is run for the four individual months, representing the four seasons, of January, May, August, and October, to produce hourly spatial maps of surface concentrations of NO3, organic aerosol (OA), and reactive organic gases (ROG, a sum of alkene species tracked in the lumped chemical mechanism employed). These "baseline" simulations are used in conjunction with literature data on secondary organic aerosol (SOA) mass yields, average organic aerosol composition, and reactive uptake coefficients for NO3 on organic surfaces to predict SOA source and OA heterogeneous loss rates due to reactions initiated by NO3. We find both source and sink rates maximized downwind of urban centers, therefore with a varying location that depends on wind direction. Both source and sink terms are maximum in summer, and SOA source dominates over OA loss by approximately three orders of magnitude, with large day-to-day variability. The NO3 source of SOA (peak production rates of 0.4–3.0 μg kg−1 h−1) is found to be significantly larger than the heterogeneous sink of OA via NO3 surface reactions (peak loss rates of 0.5–8 × 10−4 μg kg−1 h−1).

Writing Time in Metaphors

2018 ◽  
Author(s):  
Jennifer J. Smith
Keyword(s):  
United States ◽  
The United States ◽  
Western United States ◽  
Entire System ◽  
Language And Culture ◽  
Space Race ◽  
Do So

Coherence of place often exists alongside irregularities in time in cycles, and chapter three turns to cycles linked by temporal markers. Ray Bradbury’s The Martian Chronicles (1950) follows a linear chronology and describes the exploration, conquest, and repopulation of Mars by humans. Conversely, Louise Erdrich’s Love Medicine (1984) jumps back and forth across time to narrate the lives of interconnected families in the western United States. Bradbury’s cycle invokes a confluence of historical forces—time as value-laden, work as a calling, and travel as necessitating standardized time—and contextualizes them in relation to anxieties about the space race. Erdrich’s cycle invokes broader, oppositional conceptions of time—as recursive and arbitrary and as causal and meaningful—to depict time as implicated in an entire system of measurement that made possible the destruction and exploitation of the Chippewa people. Both volumes understand the United States to be preoccupied with imperialist impulses. Even as they critique such projects, they also point to the tenacity with which individuals encounter these systems, and they do so by creating “interstitial temporalities,” which allow them to navigate time at the crossroads of language and culture.

Women's Studies in the Western United States

NWSA Journal ◽  
2004 ◽  
Vol 16 (2) ◽  
pp. 180-189
Author(s):  
Karen L. Salley ◽  
Barbara Scott Winkler ◽  
Megan Celeen ◽  
Heidi Meck
Keyword(s):  
United States ◽  
Women's Studies ◽  
Western United States ◽  
Women’S Studies
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