Japan Geoscience Union Meeting 2021

Presentation information

[J] Oral

A (Atmospheric and Hydrospheric Sciences ) » A-AS Atmospheric Sciences, Meteorology & Atmospheric Environment

[A-AS05] Atmospheric Chemistry

Sun. Jun 6, 2021 3:30 PM - 5:00 PM Ch.08 (Zoom Room 08)

convener:Tomoki Nakayama(Graduate School of Fisheries and Environmental Sciences, Nagasaki University), Naoko Saitoh(Center for Environmental Remote Sensing), Sakae Toyoda(Department of Chemical Science and Engineering, Tokyo Institute of Technology), Risa Uchida(Japan Automobile Research Institute), Chairperson:Naoko Saitoh(Center for Environmental Remote Sensing), Shigeyuki Ishidoya(Advanced Industrial Science and Technology)

4:30 PM - 4:45 PM

[AAS05-21] Signal of CO2 emitted from 2020 Western U. S. wildfire captured by commercial airliner observations

*Kentaro Ishijima1, Toshinobu Machida2, Taku Umezawa2, Yosuke Niwa2,1, Kazuhiro Tsuboi1, Ryo Fujita1, Hidekazu Matsueda3,1, Taichu Y Tanaka1, Takashi Maki1, Takashi Nakamura4 (1.Meteorological Research Institute, 2.National Institute for Environmental Studies, 3.Dokkyo University, 4.Japan Meteorological Agency)

Keywords:wildfire, co2, aircraft observation

In 2020, the Western United States experienced a series of serious wildfires, ignited in August across California, Oregon, and Washington, followed by expansion of the burning in early September. In the early September, the color of the sky turned orange due to huge aerosols emitted from the wildfires in those regions. The preliminary estimate of the annual wildfire emission of CO2 in California by the California Air Resources Board is more than twice of the largest emission in the past 20 years.

The Comprehensive Observation Network for TRace gases by AIrLiners (CONTRAIL) with Continuous Measuring Equipment (CME) onboard aircraft of Japan Airlines can continuously obtain atmospheric CO2 mole fraction on the flight path. In 2020, considerable number of measurement flights to Los Angeles (~40 profiles) were carried out in September compared to previous years. Vertical profiles of CO2 mole fraction obtained by CONTRAIL-CME over Los Angeles showed high magnitude of variability throughout the troposphere, in comparison to those in September of the preceding years. This resulted in exceptionally large median and mean values of the CO2 mole fraction calculated from all profiles in September of 2020.

We also tried model simulations using the latest biomass burning emission inventory of GFED and GFAS. Preliminary simulations by an on-line atmospheric tracer transport model (GSAM-TM) reproduces some of CO2 enhancement observed in relatively wide altitude range of more than a few kilometers in the vertical profile. More detailed analysis results will be prepared in our presentation.