Identification

Title

Inferring ozone production in an urban atmosphere using measurements of peroxynitric acid

Abstract

Observations of peroxynitric acid (HO₂ NO₂ ) obtained simultaneously with those of NO and NO₂ provide a sensitive measure of the ozone photochemical production rate. We illustrate this technique for constraining the ozone production rate with observations obtained from the NCAR C-130 aircraft platform during the Megacity Initiative: Local and Global Research Observations (MILAGRO) intensive in Mexico during the spring of 2006. Sensitive and selective measurements of HO₂NO₂ were made in situ using chemical ionization mass spectrometry (CIMS). Observations were compared to modeled HO₂NO₂ concentrations obtained from the NASA Langley highly-constrained photochemical time-dependent box model. The median observed-to-calculated ratio of HO₂NO₂ is 1.18. At NOx levels greater than 15 ppbv, the photochemical box model underpredicts observations with an observed-to-calculated ratio of HO₂NO₂ of 1.57. As a result, we find that at high NOx, the ozone production rate calculated using measured HO₂NO₂ is faster than predicted using accepted photochemistry. Inclusion of an additional HOx source from the reaction of excited state NO₂ with H₂O or reduction in the rate constant of the reaction of OH with NO₂ improves the agreement.

Resource type

document

Resource locator

Unique resource identifier

code

https://n2t.org/ark:/85065/d7dj5gp1

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

2009-06-08T00:00:00Z

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