Improving Chemical Mechanisms of Reactive Nitrogen from Snowpack and Transportation in a Global Chemical Transport Model

该奖项的全部或部分资金来自《2021年美国救援计划法案》(公法117-2)。该项目的目标是改善与积雪排放的全球氮氧化物(NOx)和亚硝酸(HONO)以及道路汽油和柴油部门的HONO排放相关的化学机制。PI假设，积雪中硝酸盐气溶胶的光解(阳光反应)导致大气中NOx和HONO的产生。这项工作将改进美国臭氧产生和空气质量的模拟。这项建议的目标是(1)将与积雪排放有关的NOx/HONO化学机制的表示参数化，以及与道路汽油和柴油分部门排放相关的HONO化学机制的表示，并在全球GEOS-Chem化学运输模式中实施；以及(2)量化全球从积雪和运输中的道路汽油和柴油分部门产生的NOx/HONO来源对大气氧化剂和空气质量的影响。GEOS-Chem中最新的NOx/HONO化学机制将根据全球表面HONO和二氧化氮(NO2)观测以及来自卫星观测的对流层NO2柱密度测量进行评估。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2). The goal of this project is to improve the chemical mechanisms associated with emissions of global nitrogen oxides (NOx) and nitrous acid (HONO) from snowpack and HONO from the on-road gasoline and diesel sectors. The PI hypothesizes that the photolysis (reaction by sunlight) of nitrate aerosols in the snowpack leads to the production of NOx and HONO in the atmosphere. This work will improve the modeling of ozone production and air quality in the US.The objectives of this proposal are to (1) parameterize representations of the NOx/HONO chemical mechanisms associated with snowpack emissions, and HONO chemical mechanisms associated with on-road gasoline and diesel subsector emissions and implement these in the global GEOS-Chem chemical transport model; and (2) quantify the impacts of global missing sources of NOx/HONO production from snowpack, and on-road gasoline and diesel subsectors in transportation on atmospheric oxidants and air quality. The updated NOx/HONO chemical mechanisms in GEOS-Chem will be evaluated against global surface HONO and nitrogen dioxide (NO2) observations, as well as tropospheric NO2 column density measurements from satellite observations.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.