Characterization of Atmospheric Nitrogen Oxides Deposition over the Meadowlands

Participants: MERI, Rutgers University – Newark

Problem:

Nitrogen Oxides, which mainly come from burning fossil fuel at a high temperature, are precursor molecules for the production of ozone. Despite the critical role of NOx in air quality, the concentration levels and temporal variations of NO/NO2/Nox over the Meadowlands have not been studied.

Objective:

Generate new data on the ambient levels of NOx over the Meadowlands District
Contribute to the understanding and control of air pollution in the District to maintain the health of the Meadowlands

Strategy:

To measure the concentrations of atmospheric NO/NO2/NOx in order to assess the current levels of NOx in the ambient air
To generate temporal variation, in particular daily and seasonal trends of NOx in the ambient air

Activities:

Collect meteorological data (temperature, humidity, wind direction and speed).
To integrate the data set of NOx, environmental factors and ozone concentration to investigate the relationships and process that may control the ambient concentration of NOx
Contact with PI for the final data analysis and preparation of paper.

Deliverable:

This project will complement MERI’s ongoing air quality monitoring on VOC, EC/OC and trace elements
Results from this project can be used in the development of regional air pollution models to improve understanding of regional pollution

On November of 2006, we began operations to monitor the air above the Meadowlands District. According to the preliminary data we collected and analyzed on the spring 2007, the NO, NO2 and O3 levels at this location are within the ranges of both primary and secondary standards by NAAQS (http://www.epa.gov/air/criteria.html). The daily/8-hours averages of NO (13.8/23.9 ppb), NO2 (21.3/25.9 ppb) and O3 (24/32.5 ppb) in the spring season were smaller than other urban and other suburban site studies. Most NOx production occurred from 4 am to 8 am in a diurnal pattern that is explained by high traffic volume during the principal commute periods. On the other hand, higher ozone concentration derived by photochemical reaction between NOx and O3-O3 was produced in the afternoon by consuming of NOx. The nitrate dry deposition of 0.432kg N/ha per year, is higher than other studies.

Results from this project will help assess the current air quality over the Meadowlands and serve as a scientific base for the development of effective air pollution control strategies and new policies in the District. The results can also be used in the development of regional air pollution models. The improved models, based on these in situ measurements, offer a more accurate projection on the impact of future development on air quality in the NJMC District.