Articles | Volume 8, issue 12
Atmos. Meas. Tech., 8, 5189–5211, 2015

Special issue: Atmospheric emissions from oil sands development and their...

Atmos. Meas. Tech., 8, 5189–5211, 2015

Research article 10 Dec 2015

Research article | 10 Dec 2015

Tropospheric Emission Spectrometer (TES) satellite observations of ammonia, methanol, formic acid, and carbon monoxide over the Canadian oil sands: validation and model evaluation

M. W. Shephard1, C. A. McLinden1, K. E. Cady-Pereira2, M. Luo3, S. G. Moussa1, A. Leithead1, J. Liggio1, R. M. Staebler1, A. Akingunola1, P. Makar1, P. Lehr1, J. Zhang1, D. K. Henze4, D. B. Millet5, J. O. Bash6, L. Zhu7, K. C. Wells5, S. L. Capps4,6, S. Chaliyakunnel5, M. Gordon1,8, K. Hayden1, J. R. Brook1, M. Wolde9, and S.-M. Li1 M. W. Shephard et al.
  • 1Environment Canada, Toronto, Ontario, Canada
  • 2Atmospheric and Environmental Research (AER), Lexington, Massachusetts, USA
  • 3Jet Propulsion Laboratory (JPL), California Institute of Technology, Pasadena, California, USA
  • 4Department of Mechanical Engineering, University of Colorado, Boulder, Colorado, USA
  • 5Department of Soil, Water, and Climate, University of Minnesota, Minneapolis-St. Paul, Minnesota, USA
  • 6US Environmental Protection Agency, Research Triangle Park, North Carolina, USA
  • 7Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado, USA
  • 8Department of Earth and Space Science Engineering, York University, Toronto, Ontario, Canada
  • 9National Research Council (NRC) of Canada, Ottawa, Ontario, Canada

Abstract. The wealth of air quality information provided by satellite infrared observations of ammonia (NH3), carbon monoxide (CO), formic acid (HCOOH), and methanol (CH3OH) is currently being explored and used for a number of applications, especially at regional or global scales. These applications include air quality monitoring, trend analysis, emissions, and model evaluation. This study provides one of the first direct validations of Tropospheric Emission Spectrometer (TES) satellite-retrieved profiles of NH3, CH3OH, and HCOOH through comparisons with coincident aircraft profiles. The comparisons are performed over the Canadian oil sands region during the intensive field campaign (August–September, 2013) in support of the Joint Canada–Alberta Implementation Plan for Oil Sands Monitoring (JOSM). The satellite/aircraft comparisons over this region during this period produced errors of (i) +0.08 ± 0.25 ppbv for NH3, (ii) +7.5 ± 23 ppbv for CO, (iii) +0.19 ± 0.46 ppbv for HCOOH, and (iv) −1.1 ± 0.39 ppbv for CH3OH. These values mostly agree with previously estimated retrieval errors; however, the relatively large negative bias in CH3OH and the significantly greater positive bias for larger HCOOH and CO values observed during this study warrant further investigation. Satellite and aircraft ammonia observations during the field campaign are also used in an initial effort to perform preliminary evaluations of Environment Canada's Global Environmental Multi-scale – Modelling Air quality and CHemistry (GEM-MACH) air quality modelling system at high resolution (2.5 × 2.5 km2). These initial results indicate a model underprediction of ~ 0.6 ppbv (~ 60 %) for NH3, during the field campaign period. The TES/model CO comparison differences are ~ +20 ppbv (~ +20 %), but given that under these conditions the TES/aircraft comparisons also show a small positive TES CO bias indicates that the overall model underprediction of CO is closer to ~ 10 % at 681 hPa (~ 3 km) during this period.

Short summary
This study provides direct validations of Tropospheric Emission Spectrometer (TES) satellite retrieved profiles against coincident aircraft profiles of carbon monoxide, ammonia, methanol, and formic acid, all of which are of interest for air quality. The comparisons are performed over the Canadian oil sands region during an intensive field campaign in support of the Joint Canada-Alberta Implementation Plan for the Oil Sands Monitoring (JOSM). Initial model evaluations are also provided.