ARL Weekly May 6, 2022

ARL Weekly News – May 6, 2022

Recent Events

NOAA has announced Dr. Ariel Stein is appointed the Director, Air Resources Laboratory (ARL) effective May 8, 2022. Dr. Stein is currently Director of NOAA’s Global Monitoring Laboratory. Ariel has agreed to serve as Acting Director of NOAA’s Global Monitoring Laboratory (GML) until the permanent GML position is filled.

In January 2022, Ariel was selected to the Senior Executive Service and was appointed as the Director of NOAA’s Global Monitoring Laboratory (GML) in Boulder, Colorado. Dr. Stein became Acting Deputy Director of ARL in 2017. In his career at ARL, Ariel led the development of hybrid dispersion modeling techniques, including the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model, a widely utilized atmospheric transport and dispersion model. His research with atmospheric transport and dispersion modeling includes the simulation of atmospheric tracer release experiments, radionuclides, smoke originated from wildfires, volcanic ash, and wind-blown dust.

Dr. LaToya Myles will remain the Acting Deputy Director at ARL, a role she has held since January 2022. Dr. Myles is an environmental chemist and has previously led ARL’s Atmospheric Turbulence and Diffusion Division in Oak Ridge, TN as Director. LaToya has demonstrated leadership of boundary layer R&D efforts, including observational campaigns and modeling of physical and chemical processes in the atmosphere. She began her 20-year tenure at ARL as a fellow of the NOAA Educational Partnership Program and has become a subject matter expert, invited speaker, and published author in surface-atmosphere exchange and biogeochemical cycling of reactive nitrogen.

International Science and Engineering Fair

On 5 May, Temple Lee served as a judge, in virtual capacity, for the International Science and Engineering Fair. Temple judged a total of ten projects in the Earth and Environmental Sciences section.

Recent Publications

Publication Accepted: The U.S. power sector emissions of CO2 and NOx during 2020: Separating the impact of the COVID-19 lockdowns from the weather and decreasing coal in fuel-mix profile

D.Y. Ahn, R.J. Salawitch, T.P. Canty, H. He, X.R. Ren, D.L. Goldberg, R.R. Dickerson, The U.S. power sector emissions of CO2 and NOx during 2020: Separating the impact of the COVID-19 lockdowns from the weather and decreasing coal in fuel-mix profile, Atmospheric Environment: X, Volume 14, 2022, 100168, https://doi.org/10.1016/j.aeaoa.2022.100168.

Abstract: In recent years, the United States power sector emissions of CO2 and NOx have decreased due to declining coal and increasing natural gas and renewables in the fuel-mix. In April 2020, the COVID-19 social restrictions in the United States led to a decline in electricity demand from the commercial and industrial sectors. In this study, we estimate the changes in the emissions of CO2 and NOx from the U.S. power sector due to three factors: 1) weather, 2) the fuel-mix change in the past five years, and 3) the COVID-19 social restrictions. We use a multivariate adaptive regression splines (MARS) model to separate the impacts of outdoor temperature and type-of-day from the COVID-19 on power generation, and the daily operation status of 3013 power units to account for the fuel-mix change. We find that electricity demand changes due to COVID occurred mostly from March to June 2020, with electricity demand generally returning to 2015–2019 levels starting in July 2020. We find the U.S. power sector CO2 emissions, reported by EPA, dropped by 29.8 MTCO2 (−26%) in April 2020, relative to the average April emissions between 2015 and 2019. Of that reduction, we attribute declines of 18.3 ± 4.0 MTCO2 (−18 ± 4%) to the COVID-19 lockdowns, declines of 13.7 ± 4.2 MTCO2 (−12 ± 4%) to a fuel-mix change, and increases of 2.3 ± 1.1 MTCO2 (+2 ± 1%) due to weather variability compared to the five prior years. For the same month, the power sector NOx emissions dropped by 27.6 thousand metric tons (−42%) in April 2020, relative to the past five-year monthly average. Of that reduction, we attribute declines of 10.5 ± 2.4 thousand metric tons (−22 ± 5%) to the COVID-19 lockdowns, declines of 18.5 ± 2.5 thousand metric tons (−28 ± 4%) to a fuel-mix change, and increases of 1.4 ± 0.6 thousand metric tons (+2 ± 1%) due to weather variability. This result highlights the importance of accounting for weather and fuel-mix changes when estimating the impact of COVID-19 on the power sector emissions.