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Recent University of Toronto Papers

A complete list of publications related to MOPITT can be found on the NCAR website.

A detailed publication list from the Canadian Space Agency can be found here.

In this section a few of the University of Toronto publications will be introduced.


Quantifying Emissions of CO and NOx Using Observations From MOPITT, OMI, TES, and OSIRIS

Zhang, X., D. B. A. Jones, M. Keller, T. W. Walker, Z. Jiang, D. K. Henze, H. M. Worden, A. E. Bourassa, D. A. Degenstein, and Y. J. Rochon

Journal of Geophysical Research: Atmospheres, 124(2), 1170–1193, 2019

Summary: The GEOS-Chem four-dimensional variational data assimilation system was used to estimate emissions of carbon monoxide (CO) and nitrogen oxides (NOx) in November 2009 and July 2010. We assimilated CO retrievals from MOPITT, ozone retrievals from the TES and OSIRIS and Nitrogen Dioxide columns from OMI. By assimilating data for multiple chemical species with the four-dimensional variational scheme we obtain a consistent chemical state over the assimilation period. The modeled ozone bias was reduced to less than 3.5 ppbv everywhere, relative to independent aircraft ozone data, except in the high-latitude upper troposphere and lower stratosphere. We found that in November, the CO and NOx emission estimates obtained with the multiple species assimilation were generally comparable to those inferred from assimilating only MOPITT or OMI data, respectively, whereas in July the differences were larger. For the main anthropogenic source regions, the inferred North American and European emissions responded most strongly to the multispecies information in the assimilation. In July, North American and European CO emission estimates differed by 31% and 65% relative to the MOPITT-only estimates, respectively. We also found large differences for the North American and European NOx emission estimates, which differed by 27% and 16% relative to the OMI-only estimates, respectively. Our results highlight the potential benefit of exploiting the additional constraints offered by multispecies chemical data assimilation.

Large horizontal gradients in atmospheric CO at the synoptic scale as seen by spaceborne Measurements of Pollution in the Troposphere

Liu, J., J. R. Drummond, D. B. A. Jones, Z. Cao, H. Bremer, J. Kar, J. Zou, F. Nichitiu, and J. C. Gille

Journal of Geophysical Research: Atmospheres, 111(D2), 2006

Summary: In the MOPITT data, large horizontal gradients in CO, coherent at the synoptic scale, have been observed. The concentration of CO varies rapidly by as much as 50–100% across distances of ∼100 km, forming distinct boundaries in the CO distribution. These can last one to several days and span horizontal distances of 600–1000 km. On average, such events were observed in the MOPITT CO daily images once every 3–4 days over North America in spring and summer 2000. It was found that the large horizontal gradients typically reflect the differential vertical and horizontal transport of air with different chemical signatures. The results demonstrate that MOPITT can capture the influence of synoptic processes on the horizontal and vertical distribution of CO. The large gradients in CO observed on synoptic scales represent valuable information that can be exploited to improve our understanding of atmospheric CO. In particular, these results suggest that the MOPITT observations provide a useful data set with which to address a range of issues from air quality on local/regional scales to long‐range transport of pollution on continental/global scales.


Carbon monoxide (CO) maximum over the Zagros mountains in the Middle East: Signature of mountain venting?

Kar, J., J. R. Drummond, D. B. A. Jones, J. Liu, F. Nichitiu, J. Zou, J. C. Gille, D. P. Edwards, and M. N. Deeter

Geophysical Research Letters, 33(15), L15819, 2006

Summary: Enhanced CO is observed over the Zagros mountains of Iran, following the local topography over this region (25–40N, 40–60E). The MOPITT averaging kernels do not seem to indicate any data artifacts in this area. We argue that this feature likely forms by the process of mountain venting by thermal winds caused by strong daytime differential heating. This is consistent with an analysis of vertical velocity in the NCEP reanalysis data in this region. The phenomenon was observed in all the years of available MOPITT measurements and may have implications for the pollution episodes in the region and the Middle East ozone maximum that has been observed earlier.


Solar particle events seen by the MOPITT instrument

Florian Nichitiu, James R. Drummond , Jiansheng Zou , Robert Deschambault

Journal of Atmospheric and Solar-Terrestrial Physics, 66(18), pp 1797-1803, 2004

Summary: This paper reports on Device Single Events (DSEs) occurring in the Measurements Of Pollution In The Troposphere (MOPITT) space instrument piezoelectric accelerometers. It is found that DSEs correlate with the radiation environment, solar activity and high intensity Solar Proton Events.

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Evidence of vertical transport of carbon monoxide from Measurements of Pollution in the Troposphere (MOPITT)

Jayanta Kar, Holger Bremer, James R. Drummond, Yves J. Rochon, Dylan B. A. Jones, Florian Nichitiu, Jason Zou, Jane Liu, John C. Gille, David P. Edwards, Merritt N. Deeter, Gene Francis, Dan Ziskin, and Juying Warner

Geophysical Research Letters, 31, L23105

Summary: Vertical profiles of carbon monoxide (CO) mixing ratio retrieved from MOPITT measurements have been analyzed. It was find that variations in the vertical structure of CO can be detected in the MOPITT data. The Asian summer monsoon plume in CO is observed for the first time as a strong enhancement of CO in the upper troposphere (UT) over India and southern China indicating the effect of deep convective transport. Similarly, zonal mean height latitude cross‐sections for the months of September–December, 2002 indicate deep convective transport of CO from biomass burning in the southern tropics. These findings show that MOPITT CO can provide valuable information on vertical transport phenomena in the troposphere.