Identification

Title

Data- and model-based urban O3 responses to NOx changes in China and the United States

Abstract

Urban air pollution continues to pose a significant health threat, despite regulations to control emissions. Here we present a comparative analysis of urban ozone (O-3) responses to nitrogen oxide (NOx) changes in China and the United States (US) over 2015-2020 by integrating various data- and model-based methods. The data-based deep learning (DL) model exhibited good performance in simulating urban air quality: the correlation coefficients (R) of O-3 daily variabilities with respect to independent O-3 observations are 0.88 and 0.79 over N. China, 0.87 and 0.90 over S. China, and 0.87 and 0.49 over E. United States by the DL and GEOS-Chem chemical transport models, respectively. Furthermore, the data-based methods suggest volatile organic compound (VOC)-limited regimes in urban areas over northern inland China and transitional regimes over eastern US urban areas; in contrast, GEOS-Chem model suggests strong NOx-limited regimes. Sensitivity analysis indicates that the inconsistent O-3 responses are partially caused by the inaccurate representation of O-3 precursor concentrations at the locations of urban air quality stations in the simulations, while the data-based methods are driven by the variabilities in local O-3 precursor concentrations and meteorological conditions. The O-3 responses to NOx changes reported here provide a better understanding of urban O-3 pollution; for example, reductions in NOx emissions are suggested to have resulted in an increase in surface O-3 by approximately 7 ppb in the Sichuan Basin in 2014-2020.

Resource type

document

Resource locator

Unique resource identifier

code

https://n2t.org/ark:/85065/d7rj4pjf

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

2023-10-27T00:00:00Z

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