ARL Weekly News – April 10, 2020

Recent Events

Research Flights: Xinrong Ren and Winston Luke submitted a project topic for a joint NESDIS-OAR collaborative effort to gather ideas for joint research projects that address impacts on the Earth system during the economic hiatus caused by the COVID-19 crisis, as well as during the eventual recovery. The proposal would fund a privately contracted Cessna that ARL operates in conjunction with the University of Maryland to measure levels of CO, CO2, CH4, O3, NOx, and SO2 in the Washington, D.C. and Baltimore metro areas. The specific goals of the project would be to conduct vertical profiles of aircraft O3, CO, SO2, NO2, CO4, CH4 and AOD from near the surface to up to ~20kft, for the evaluation of satellite observations; use the observed ratios of trace gases (like CO/CO2, CH4/CO2, BC (black carbon)/CO2, SO2/CO2, NOx/CO2, etc.) to compare to the same ratios observed by satellites; and to evaluate emission inventories. In addition to being used for satellite evaluation studies, the observations can be used for inverse modeling and for HYSPLIT evaluation and optimization studies. The timeline for project selection and funding is to be determined; however, the National Institute of Standards and Technology and Maryland Department of Environment are interested in similar research flights. The team plans to install aircraft instruments on the Cessna on April 13, after which they’ll be ready to begin flying during the week.


“Undercatch adjustments for tipping bucket gauge measurements of solid precipitation, by Kochendorfer, John; Earle, Michael E.; Hodyss, Daniel; Reverdin, Audrey; Roulet, Yves-Alain; Nitu, Rodica; Rasmussen, Roy; Landolt, Scott; Buisan, Samuel; and Laine, Timo was accepted for publication in the Journal of Hydrometeorology. This manuscript describes the derivation and testing of transfer functions for the improvement of tipping bucket precipitation gauge measurements. It was based on WMO-SPICE measurements from six different types of gauges, tested at five different precipitation testbeds. It also introduces a new approach to transfer function derivation that can be used for other types of precipitation measurements.

“The potential for uncertainty in Numerical Weather Prediction model verification when using solid precipitation observations, by Buisán, Samuel T.; Smith, Craig D.; Ross, Amber; Kochendorfer, John; Collado, José Luís; Alastrué, Javier; Wolff, Mareile; Roulet, Yves-Alain; Earle, Michael E.; Laine, Timo; Rasmussen, Roy; and Nitu, Rodica was accepted for publication in Atmospheric Research Letters. It describes the importance and shortcomings of solid precipitation gauge adjustments for validating weather forecast models.

“A multi-scale model analysis of ozone formation in the Bangkok Metropolitan Region, Thailand, by Pornpan Uttamang, Patrick C. Campbell, Viney P. Aneja and Adel F. Hanna, is published in Atmospheric Environment and available online at:

“Assessment of NO2 observations during DISCOVER-AQ and KORUS-AQ field campaigns, by Sungyeon Choi, Lok N. Lamsal, Melanie Follette-Cook, Joanna Joiner, Nickolay A. Krotkov, William H. Swartz, Kenneth E. Pickering, Christopher P. Loughner, Wyat Appel, Gabriele Pfister, Pablo E. Saide, Ronald C. Cohen, Andrew J. Weinheimer, and Jay R. Herman, was accepted for publication in Atmospheric Measurement Techniques.