TY - JOUR AU - Sally Newman AU - Seongeun Jeong AU - Marc L Fischer AU - Xiaomei Xu AU - Christine L Haman AU - Barry Lefer AU - Sergio Alvarez AU - Bernhard Rappenglueck AU - Eric A Kort AU - Arlyn E Andrews AU - Jeffrey Peischl AU - Kevin R Gurney AU - Charles E Miller AU - Yuk L Yung AB -

Attributing observed CO2 variations to human or natural cause is critical to deducing and tracking emissions from observations. We have used in situ CO2, CO, and planetary boundary layer height (PBLH) measurements recorded during the CalNex-LA (CARB et al., 2008) ground campaign of 15 May–15 June 2010, in Pasadena, CA, to deduce the diurnally varying anthropogenic component of observed CO2 in the megacity of Los Angeles (LA). This affordable and simple technique, validated by carbon isotope observations and WRF-STILT (Weather Research and Forecasting model – Stochastic Time-Inverted Lagrangian Transport model) predictions, is shown to robustly attribute observed CO2 variation to anthropogenic or biogenic origin over the entire diurnal cycle. During CalNex-LA, local fossil fuel combustion contributed up to ~50% of the observed CO2 enhancement overnight, and ~100% of the enhancement near midday. This suggests that sufficiently accurate total column CO2 observations recorded near midday, such as those from the GOSAT or OCO-2 satellites, can potentially be used to track anthropogenic emissions from the LA megacity.

BT - Atmospheric Chemistry and Physics DA - 04/2013 DO - 10.5194/acp-13-4359-2013 IS - 8 N2 -

Attributing observed CO2 variations to human or natural cause is critical to deducing and tracking emissions from observations. We have used in situ CO2, CO, and planetary boundary layer height (PBLH) measurements recorded during the CalNex-LA (CARB et al., 2008) ground campaign of 15 May–15 June 2010, in Pasadena, CA, to deduce the diurnally varying anthropogenic component of observed CO2 in the megacity of Los Angeles (LA). This affordable and simple technique, validated by carbon isotope observations and WRF-STILT (Weather Research and Forecasting model – Stochastic Time-Inverted Lagrangian Transport model) predictions, is shown to robustly attribute observed CO2 variation to anthropogenic or biogenic origin over the entire diurnal cycle. During CalNex-LA, local fossil fuel combustion contributed up to ~50% of the observed CO2 enhancement overnight, and ~100% of the enhancement near midday. This suggests that sufficiently accurate total column CO2 observations recorded near midday, such as those from the GOSAT or OCO-2 satellites, can potentially be used to track anthropogenic emissions from the LA megacity.

PY - 2012 SP - 4359 EP - 4372 ST - Atmos. Chem. Phys. T2 - Atmospheric Chemistry and Physics TI - Diurnal tracking of anthropogenic CO2 emissions in the Los Angeles basin megacity during spring 2010 UR - http://www.atmos-chem-phys.net/13/4359/2013/ VL - 13 ER -