Identification

Title

Emissions of reactive nitrogen from Western U.S. wildfires during summer 2018

Abstract

Reactive nitrogen (N-r) within smoke plumes plays important roles in the production of ozone, the formation of secondary aerosols, and deposition of fixed N to ecosystems. The Western Wildfire Experiment for Cloud Chemistry, Aerosol Absorption, and Nitrogen (WE-CAN) field campaign sampled smoke from 23 wildfires throughout the western U.S. during summer 2018 using the NSF/NCAR C-130 research aircraft. We empirically estimate N-r normalized excess mixing ratios and emission factors from fires sampled within 80 min of estimated emission and explore variability in the dominant forms of N-r between these fires. We find that reduced N compounds comprise a majority (39%-80%; median = 66%) of total measured reactive nitrogen (Sigma N-r) emissions. The smoke plumes sampled during WE-CAN feature rapid chemical transformations after emission. As a result, within minutes after emission total measured oxidized nitrogen (Sigma NOy) and measured total Sigma NHx (NH3 + pNH(4)) are more robustly correlated with modified combustion efficiency (MCE) than NOx and NH3 by themselves. The ratio of Sigma NHx/Sigma NOy displays a negative relationship with MCE, consistent with previous studies. A positive relationship with total measured Sigma N-r suggests that both burn conditions and fuel N content/volatilization differences contribute to the observed variability in the distribution of reduced and oxidized N-r. Additionally, we compare our in situ field estimates of N-r EFs to previous lab and field studies. For similar fuel types, we find Sigma NHx EFs are of the same magnitude or larger than lab-based NH3 EF estimates, and Sigma NOy EFs are smaller than lab NOx EFs.

Resource type

document

Resource locator

Unique resource identifier

code

https://n2t.org/ark:/85065/d7g44tmc

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

geoscientificInformation

Keywords

Keyword set

keyword value

Text

originating controlled vocabulary

title

Resource Type

reference date

date type

publication

effective date

2016-01-01T00:00:00Z

Geographic location

West bounding longitude

East bounding longitude

North bounding latitude

South bounding latitude

Temporal reference

Temporal extent

Begin position

End position

Dataset reference date

date type

publication

effective date

2021-01-27T00:00:00Z

Frequency of update

Quality and validity

Lineage

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

Limitations on public access

None

Responsible organisations

Responsible party

contact position

OpenSky Support

organisation name

UCAR/NCAR - Library

full postal address

PO Box 3000

Boulder

80307-3000

email address

opensky@ucar.edu

web address

http://opensky.ucar.edu/

name: homepage

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact