Sulfur dioxide (SO<sub>2</sub>) vertical column density measurements by Pandora spectrometer over the Canadian oil sands
Vertical column densities (VCDs) of SO<sub>2</sub> retrieved by a Pandora spectral sun photometer at Fort McKay, Alberta, Canada, from 2013 to 2015 were analysed. The Fort McKay site is located in the Canadian oil sands region, approximately 20 km north of two major SO<sub>2</su...
Main Authors: | , , , , , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
Copernicus Publications
2016-07-01
|
Series: | Atmospheric Measurement Techniques |
Online Access: | http://www.atmos-meas-tech.net/9/2961/2016/amt-9-2961-2016.pdf |
_version_ | 1818265639346765824 |
---|---|
author | V. E. Fioletov C. A. McLinden A. Cede J. Davies C. Mihele S. Netcheva S.-M. Li J. O'Brien |
author_facet | V. E. Fioletov C. A. McLinden A. Cede J. Davies C. Mihele S. Netcheva S.-M. Li J. O'Brien |
author_sort | V. E. Fioletov |
collection | DOAJ |
description | Vertical column densities (VCDs) of SO<sub>2</sub> retrieved by
a Pandora spectral sun photometer at Fort McKay, Alberta, Canada, from
2013 to 2015 were analysed. The Fort McKay site is located in the Canadian oil
sands region, approximately 20 km north of two major SO<sub>2</sub> sources
(upgraders), with total emission of about 45 kt yr<sup>−1</sup>. Elevated SO<sub>2</sub>
VCD values were frequently recorded by the instrument, with the highest
values of about 9 Dobson Units (DU; DU = 2.69 × 10<sup>16</sup> molecules cm<sup>−2</sup>). Comparisons with co-located in situ
measurements demonstrated that there was a very good correlation between
VCDs and surface concentrations in some cases, while in other cases, elevated
VCDs did not correspond to high surface concentrations, suggesting the plume
was above the ground. Elevated VCDs and surface concentrations were observed
when the wind direction was from south to southeast, i.e. from the direction
of the two local SO<sub>2</sub> sources. The precision of the SO<sub>2</sub>
measurements, estimated from parallel measurements by two Pandora
instruments at Toronto, is 0.17 DU. The total uncertainty of Pandora
SO<sub>2</sub> VCD, estimated using measurements when the wind direction was away
from the sources, is less than 0.26 DU (1<i>σ</i>). Comparisons with
integrated SO<sub>2</sub> profiles from concurrent aircraft measurements support
these estimates. |
first_indexed | 2024-12-12T19:54:00Z |
format | Article |
id | doaj.art-83b2b981794146b19617fa5cd5f04854 |
institution | Directory Open Access Journal |
issn | 1867-1381 1867-8548 |
language | English |
last_indexed | 2024-12-12T19:54:00Z |
publishDate | 2016-07-01 |
publisher | Copernicus Publications |
record_format | Article |
series | Atmospheric Measurement Techniques |
spelling | doaj.art-83b2b981794146b19617fa5cd5f048542022-12-22T00:13:56ZengCopernicus PublicationsAtmospheric Measurement Techniques1867-13811867-85482016-07-01972961297610.5194/amt-9-2961-2016Sulfur dioxide (SO<sub>2</sub>) vertical column density measurements by Pandora spectrometer over the Canadian oil sandsV. E. Fioletov0C. A. McLinden1A. Cede2J. Davies3C. Mihele4S. Netcheva5S.-M. Li6J. O'Brien7Environment Canada and Climate Change Canada, Toronto, ON, CanadaEnvironment Canada and Climate Change Canada, Toronto, ON, CanadaNASA Goddard Space Flight Center, Greenbelt, MD, USAEnvironment Canada and Climate Change Canada, Toronto, ON, CanadaEnvironment Canada and Climate Change Canada, Toronto, ON, CanadaEnvironment Canada and Climate Change Canada, Toronto, ON, CanadaEnvironment Canada and Climate Change Canada, Toronto, ON, CanadaEnvironment Canada and Climate Change Canada, Toronto, ON, CanadaVertical column densities (VCDs) of SO<sub>2</sub> retrieved by a Pandora spectral sun photometer at Fort McKay, Alberta, Canada, from 2013 to 2015 were analysed. The Fort McKay site is located in the Canadian oil sands region, approximately 20 km north of two major SO<sub>2</sub> sources (upgraders), with total emission of about 45 kt yr<sup>−1</sup>. Elevated SO<sub>2</sub> VCD values were frequently recorded by the instrument, with the highest values of about 9 Dobson Units (DU; DU = 2.69 × 10<sup>16</sup> molecules cm<sup>−2</sup>). Comparisons with co-located in situ measurements demonstrated that there was a very good correlation between VCDs and surface concentrations in some cases, while in other cases, elevated VCDs did not correspond to high surface concentrations, suggesting the plume was above the ground. Elevated VCDs and surface concentrations were observed when the wind direction was from south to southeast, i.e. from the direction of the two local SO<sub>2</sub> sources. The precision of the SO<sub>2</sub> measurements, estimated from parallel measurements by two Pandora instruments at Toronto, is 0.17 DU. The total uncertainty of Pandora SO<sub>2</sub> VCD, estimated using measurements when the wind direction was away from the sources, is less than 0.26 DU (1<i>σ</i>). Comparisons with integrated SO<sub>2</sub> profiles from concurrent aircraft measurements support these estimates.http://www.atmos-meas-tech.net/9/2961/2016/amt-9-2961-2016.pdf |
spellingShingle | V. E. Fioletov C. A. McLinden A. Cede J. Davies C. Mihele S. Netcheva S.-M. Li J. O'Brien Sulfur dioxide (SO<sub>2</sub>) vertical column density measurements by Pandora spectrometer over the Canadian oil sands Atmospheric Measurement Techniques |
title | Sulfur dioxide (SO<sub>2</sub>) vertical column density measurements by Pandora
spectrometer over the Canadian oil sands |
title_full | Sulfur dioxide (SO<sub>2</sub>) vertical column density measurements by Pandora
spectrometer over the Canadian oil sands |
title_fullStr | Sulfur dioxide (SO<sub>2</sub>) vertical column density measurements by Pandora
spectrometer over the Canadian oil sands |
title_full_unstemmed | Sulfur dioxide (SO<sub>2</sub>) vertical column density measurements by Pandora
spectrometer over the Canadian oil sands |
title_short | Sulfur dioxide (SO<sub>2</sub>) vertical column density measurements by Pandora
spectrometer over the Canadian oil sands |
title_sort | sulfur dioxide so sub 2 sub vertical column density measurements by pandora spectrometer over the canadian oil sands |
url | http://www.atmos-meas-tech.net/9/2961/2016/amt-9-2961-2016.pdf |
work_keys_str_mv | AT vefioletov sulfurdioxidesosub2subverticalcolumndensitymeasurementsbypandoraspectrometeroverthecanadianoilsands AT camclinden sulfurdioxidesosub2subverticalcolumndensitymeasurementsbypandoraspectrometeroverthecanadianoilsands AT acede sulfurdioxidesosub2subverticalcolumndensitymeasurementsbypandoraspectrometeroverthecanadianoilsands AT jdavies sulfurdioxidesosub2subverticalcolumndensitymeasurementsbypandoraspectrometeroverthecanadianoilsands AT cmihele sulfurdioxidesosub2subverticalcolumndensitymeasurementsbypandoraspectrometeroverthecanadianoilsands AT snetcheva sulfurdioxidesosub2subverticalcolumndensitymeasurementsbypandoraspectrometeroverthecanadianoilsands AT smli sulfurdioxidesosub2subverticalcolumndensitymeasurementsbypandoraspectrometeroverthecanadianoilsands AT jobrien sulfurdioxidesosub2subverticalcolumndensitymeasurementsbypandoraspectrometeroverthecanadianoilsands |