Greenhouse Gas and Nitrogen Inventory Report for Municipal and School Operations

The City of Dover recognizes the many challenges that a changing climate presents and acknowledges that municipalities have a responsibility to lead adaptation and greenhouse gas reduction efforts at the local level. Through a University of New Hampshire Sustainability Fellowship undertaken by UNH doctoral student Jackson Kaspari, the City of Dover has become the first municipality in North America to complete a baseline footprint for both greenhouse gas (GHG) and nitrogen impacts of local government operations. This inventory informs Dover’s policymakers, residents, property owners, and business owners on how to best introduce mitigation measures, helping Dover contribute to a global effort. Conducting a GHG and nitrogen inventory serves the following purposes: allows for the development of a baseline to which further GHG and nitrogen analyses can be compared, leads to the identification of opportunities to improve energy efficiency, leads to the identification of opportunities to reduce nitrogen releases to the environment, demonstrates climate change leadership through the development of reduction targets, and increases the general transparency and consistency of GHG and nitrogen accounting and reporting among institutions. This carbon and nitrogen footprint baseline was compiled through the utilization of two online tools: the Environmental Protection Agency’s Portfolio Manager and the University of New Hampshire’s Sustainability Indicator Management and Analysis Platform (SIMAP). The inventory is organized into categories, or sectors, which represent the major sources of carbon and nitrogen emissions. Most sectors contribute to both types of emissions. The sectors analyzed in this report include: stationary fuels, purchased electricity, the municipal fleet, employee commuting, employee travel, fertilizer and animals, school cafeteria food, solid waste, paper use, transmission and distribution losses, and wastewater treatment. In addition to analyzing the energy use and GHG impacts for each sector, the City’s energy costs have also been calculated for both 2016 and 2017. Overall, municipal operations generated 9,896 metric tons of carbon dioxide equivalent (MT of C02e) in 2016 and 9,560 MT of C02e in 2017, representing a 3.4% reduction from year to year. Reactive nitrogen released to the environment was 40 MT and 42.3 MT in 2016 and 2017, respectively, a 5.4% increase. Figures for each sector and each year are included, and the likely causes of increases or reductions are presented. This inventory concludes with models of the impact of projects that are already underway as well as reduction scenarios that the City and schools may opt to pursue. It also includes recommendations for improving upon data collection in future years and appendices detailing energy use at each facility

Isotopic evidence for dominant secondary production of HONO in near-ground wildfire plumes

Nitrous acid (HONO) is an important precursor to hydroxyl radical (OH) that determines atmospheric oxidative capacity and thus impacts climate and air quality. Wildfire is not only a major direct source of HONO, it also results in highly polluted conditions that favor the heterogeneous formation of HONO from nitrogen oxides (NOx= NO + NO2) and nitrate on both ground and particle surfaces. However, these processes remain poorly constrained. To quantitatively constrain the HONO budget under various fire and/or smoke conditions, we combine a unique dataset of field concentrations and isotopic ratios (15N / 14N and 18O / 16O) of NOx and HONO with an isotopic box model. Here we report the first isotopic evidence of secondary HONO production in near-ground wildfire plumes (over a sample integration time of hours) and the subsequent quantification of the relative importance of each pathway to total HONO production. Most importantly, our results reveal that nitrate photolysis plays a minor role (\u3c5 %) in HONO formation in daytime aged smoke, while NO2-to-HONO heterogeneous conversion contributes 85 %–95 % to total HONO production, followed by OH + NO (5 %–15 %). At nighttime, heterogeneous reduction of NO2 catalyzed by redox active species (e.g., iron oxide and/or quinone) is essential (≥ 75 %) for HONO production in addition to surface NO2 hydrolysis. Additionally, the 18O / 16O of HONO is used for the first time to constrain the NO-to-NO2 oxidation branching ratio between ozone and peroxy radicals. Our approach provides a new and critical way to mechanistically constrain atmospheric chemistry and/or air quality models on a diurnal timescale

Fire Influence on Regional to Global Environments and Air Quality (FIREX‐AQ)

The NOAA/NASA Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) experiment was a multi-agency, inter-disciplinary research effort to: (a) obtain detailed measurements of trace gas and aerosol emissions from wildfires and prescribed fires using aircraft, satellites and ground-based instruments, (b) make extensive suborbital remote sensing measurements of fire dynamics, (c) assess local, regional, and global modeling of fires, and (d) strengthen connections to observables on the ground such as fuels and fuel consumption and satellite products such as burned area and fire radiative power. From Boise, ID western wildfires were studied with the NASA DC-8 and two NOAA Twin Otter aircraft. The high-altitude NASA ER-2 was deployed from Palmdale, CA to observe some of these fires in conjunction with satellite overpasses and the other aircraft. Further research was conducted on three mobile laboratories and ground sites, and 17 different modeling forecast and analyses products for fire, fuels and air quality and climate implications. From Salina, KS the DC-8 investigated 87 smaller fires in the Southeast with remote and in-situ data collection. Sampling by all platforms was designed to measure emissions of trace gases and aerosols with multiple transects to capture the chemical transformation of these emissions and perform remote sensing observations of fire and smoke plumes under day and night conditions. The emissions were linked to fuels consumed and fire radiative power using orbital and suborbital remote sensing observations collected during overflights of the fires and smoke plumes and ground sampling of fuels