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Abstract Oil and gas production regions are significant sources of greenhouse gases and reactive pollutants such as nitrogen oxides (NO_x) and volatile organic compounds. Research has also shown that methane (CH₄) emissions reported to the Environmental Protection Agency's (EPA) Greenhouse Gas Reporting Program (GHGRP) are generally underestimated. The Arctic accounted for 5.5% of global oil and gas production in 2022 but is estimated to contain significant undiscovered resources. The emitted NO_xand volatile organic compounds can impact the composition and chemistry of the Arctic atmosphere. The Prudhoe Bay Oil Field in Alaska is one of the 10 largest oil fields in the US and has been approved for significant development expansion. However, only one recent study has reported measurements of its greenhouse gas emissions. We estimate the emission rates for carbon dioxide (CO₂), CH₄, and NO_xfrom the Prudhoe Bay Oil Field during the spring of 2022 using airborne mass balance methods and emission ratios. We also discuss emissions per energy produced and show an increase over time, with values higher than the national average for oil and gas producing regions, though within uncertainties. Our estimates are lower than the NO_xemission estimate reported in the National Emissions Inventory (NEI), as seen in other oil and gas studies, but fall within the uncertainty range of the greenhouse gases reported in the GHGRP. This work provides a valuable snapshot of emissions before further expansion of extraction activities. 

This flux-tower observational campaign occurred in Utqiagvik, AK. A 12-m tower was installed in February 2022 to collect turbulence data at a total of five heights (0.5 m, 1.5 m, 2.5 m, 3.5 m, and 7.5 m). At each height, a Campbell Scientific CSAT3B sonic anemometer was operated to measure three velocity components and virtual temperature at 50 Hz, and an R. M. Young temperature and relative sensor was operated to measure air temperature and relative humidity at 1 Hz. The effective data collection was during March--April 2022, until the tower was taken down in April 2022. This was the first dataset of Arctic turbulence collected at 50 Hz, a frequency substantially higher than previous measurements at 10 Hz and 20 Hz. Given the strongly stable conditions in the Arctic, increasing the sampling frequency to 50 Hz was critical to resolve near-surface turbulence within or at least close to the inertial subrange. 

Abstract We mapped tidal wetland gross primary production (GPP) with unprecedented detail for multiple wetland types across the continental United States (CONUS) at 16‐day intervals for the years 2000–2019. To accomplish this task, we developed the spatially explicit Blue Carbon (BC) model, which combined tidal wetland cover and field‐based eddy covariance tower data into a single Bayesian framework, and used a super computer network and remote sensing imagery (Moderate Resolution Imaging Spectroradiometer Enhanced Vegetation Index). We found a strong fit between the BC model and eddy covariance data from 10 different towers (r²= 0.83,p< 0.001, root‐mean‐square error = 1.22 g C/m²/day, average error was 7% with a mean bias of nearly zero). When compared with NASA's MOD17 GPP product, which uses a generalized terrestrial algorithm, the BC model reduced error by approximately half (MOD17 hadr²= 0.45,p< 0.001, root‐mean‐square error of 3.38 g C/m²/day, average error of 15%). The BC model also included mixed pixels in areas not covered by MOD17, which comprised approximately 16.8% of CONUS tidal wetland GPP. Results showed that across CONUS between 2000 and 2019, the average daily GPP per m²was 4.32 ± 2.45 g C/m²/day. The total annual GPP for the CONUS was 39.65 ± 0.89 Tg C/year. GPP for the Gulf Coast was nearly double that of the Atlantic and Pacific Coasts combined. Louisiana alone accounted for 15.78 ± 0.75 Tg C/year, with its Atchafalaya/Vermillion Bay basin at 4.72 ± 0.14 Tg C/year. The BC model provides a robust platform for integrating data from disparate sources and exploring regional trends in GPP across tidal wetlands.