Worldwide efforts to contain spreading of the COVID-19 pandemic have reduced emissions from surface traffic by about 15% on average over the year 2020. Air-traffic (and emissions) went down by 40% on average.
Traffic is a main source of nitrogen oxides in the atmosphere, and much of the ozone in the troposphere is produced by photochemical reactions involving nitrogen oxides and volatile organic compounds (VOCs).
Congratulations to Dr. Ryan Stauffer for his appointment to a Civil Service position in the NASA Goddard Space Flight Center Atmospheric Chemistry and Dynamics Laboratory within the Earth Sciences Division! This appointment is effective 1 March 2021. Ryan is a member of the NDACC Steering Committee, and has been serving as Sonde Working Group Co-Chair since the 2020 annual meeting.
As previously announced, we currently are making plans to hold the 2021 NDACC Steering Committee meeting in College Park, MD, the week of 13-17 September 2021. With the ongoing restrictions associated with the COVID-19 pandemic, it remains unclear if we will be able to have a face-to-face meeting this year. We are going to make a decision in mid April regarding the meeting format. In the meantime, we ask that you note the dates on your calendar. Whether it be face-to-face or virtual, we hope that as many of you will participate in the meeting as possible.
Total columns of the trace gases nitric acid (HNO3) and hydrogen chloride (HCl) are sensitive to variations in the lower stratospheric age of air (AoA), a quantity that describes transport timescales in the stratosphere. We analyzed HNO3 and HCl columns from 9 NDACC FTIR sites spanning 77oS to 79oN and detected changes in the extratropical stratospheric transport circulation from 1994 to 2018.
The NDACC Steering Committee held its annual meeting 4-6 November 2020. Originally scheduled to take place at the NOAA Center for Weather and Climate Prediction (NCWCP) in College Park, MD, the meeting was changed to a virtual format because of ongoing COVID-19 restrictions. The agenda was compressed into three short sessions, but attendees still were able to discuss a wide variety of topics, including station and data submission status, implementation of Digital Object Identifiers (DOIs), changes to the NDACC Data Protocol, the addition of Data Versioning options, new relationships with