Deriving tropospheric ozone from assimilated profiles
<p>We derived global tropospheric ozone (<span class="inline-formula">O<sub>3</sub></span>) columns from GOME-2A (Global Ozone Monitoring Experiment) and OMI (Ozone Monitoring Instrument) <span class="inline-formula">O<sub>3</sub>&l...
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2019-06-01
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| Series: | Atmospheric Chemistry and Physics |
| Online Access: | https://www.atmos-chem-phys.net/19/8297/2019/acp-19-8297-2019.pdf |
| _version_ | 1819078458935869440 |
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| author | J. C. A. van Peet J. C. A. van Peet R. J. van der A R. J. van der A |
| author_facet | J. C. A. van Peet J. C. A. van Peet R. J. van der A R. J. van der A |
| author_sort | J. C. A. van Peet |
| collection | DOAJ |
| description | <p>We derived global tropospheric ozone (<span class="inline-formula">O<sub>3</sub></span>) columns from GOME-2A (Global Ozone Monitoring Experiment) and OMI (Ozone Monitoring Instrument) <span class="inline-formula">O<sub>3</sub></span> profiles, which were simultaneously assimilated into the TM5 (Tracer Model, version 5) global
chemistry transport model for the year <span class="inline-formula">2008</span>.
The horizontal model resolution has been increased by a factor of <span class="inline-formula">6</span> for more accurate
results. To reduce computational cost, the number of model layers
has been reduced from <span class="inline-formula">44</span> to <span class="inline-formula">31</span>. The model ozone fields are used to
derive tropospheric ozone, which is defined here as the partial column
between mean sea level and <span class="inline-formula">6</span> <span class="inline-formula">km</span> altitude. Two methods for
calculating the tropospheric columns from the free model run and
assimilated <span class="inline-formula">O<sub>3</sub></span> fields are compared. In the first method, we
calculate the residual between assimilated total columns and the partial
model column between <span class="inline-formula">6</span> <span class="inline-formula">km</span> and the top of atmosphere. In the
second method, we perform a direct integration of the assimilated
<span class="inline-formula">O<sub>3</sub></span> fields between the surface and <span class="inline-formula">6</span> <span class="inline-formula">km</span>. The results
are validated against tropospheric columns derived from ozone sonde
measurements. Our results show that the residual method has too large a variation to be used reliably for the determination of tropospheric
ozone, so the direct integration method has been used instead. The
median global bias is smaller for the assimilated <span class="inline-formula">O<sub>3</sub></span> fields than
for the free model run, but the large variation makes it difficult to
make definitive statements on a regional or local scale. The monthly
mean ozone fields show significant improvements and more detail when
comparing the assimilated <span class="inline-formula">O<sub>3</sub></span> fields with the free model run,
especially for features such as biomass-burning-enhanced <span class="inline-formula">O<sub>3</sub></span>
concentrations and outflow of <span class="inline-formula">O<sub>3</sub></span> rich air from Asia over the
Pacific.</p> |
| first_indexed | 2024-12-21T19:13:25Z |
| format | Article |
| id | doaj.art-5bca2052e52841a0b2944ac27b38c0e3 |
| institution | Directory Open Access Journal |
| issn | 1680-7316 1680-7324 |
| language | English |
| last_indexed | 2024-12-21T19:13:25Z |
| publishDate | 2019-06-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Atmospheric Chemistry and Physics |
| spelling | doaj.art-5bca2052e52841a0b2944ac27b38c0e32022-12-21T18:53:08ZengCopernicus PublicationsAtmospheric Chemistry and Physics1680-73161680-73242019-06-01198297830910.5194/acp-19-8297-2019Deriving tropospheric ozone from assimilated profilesJ. C. A. van Peet0J. C. A. van Peet1R. J. van der A2R. J. van der A3Royal Netherlands Meteorological Institute (KNMI), De Bilt, the NetherlandsDepartment of Earth Sciences, Vrije Universiteit Amsterdam, Amsterdam, the NetherlandsRoyal Netherlands Meteorological Institute (KNMI), De Bilt, the NetherlandsNanjing University of Information Science & Technology (NUIST), Nanjing, China<p>We derived global tropospheric ozone (<span class="inline-formula">O<sub>3</sub></span>) columns from GOME-2A (Global Ozone Monitoring Experiment) and OMI (Ozone Monitoring Instrument) <span class="inline-formula">O<sub>3</sub></span> profiles, which were simultaneously assimilated into the TM5 (Tracer Model, version 5) global chemistry transport model for the year <span class="inline-formula">2008</span>. The horizontal model resolution has been increased by a factor of <span class="inline-formula">6</span> for more accurate results. To reduce computational cost, the number of model layers has been reduced from <span class="inline-formula">44</span> to <span class="inline-formula">31</span>. The model ozone fields are used to derive tropospheric ozone, which is defined here as the partial column between mean sea level and <span class="inline-formula">6</span> <span class="inline-formula">km</span> altitude. Two methods for calculating the tropospheric columns from the free model run and assimilated <span class="inline-formula">O<sub>3</sub></span> fields are compared. In the first method, we calculate the residual between assimilated total columns and the partial model column between <span class="inline-formula">6</span> <span class="inline-formula">km</span> and the top of atmosphere. In the second method, we perform a direct integration of the assimilated <span class="inline-formula">O<sub>3</sub></span> fields between the surface and <span class="inline-formula">6</span> <span class="inline-formula">km</span>. The results are validated against tropospheric columns derived from ozone sonde measurements. Our results show that the residual method has too large a variation to be used reliably for the determination of tropospheric ozone, so the direct integration method has been used instead. The median global bias is smaller for the assimilated <span class="inline-formula">O<sub>3</sub></span> fields than for the free model run, but the large variation makes it difficult to make definitive statements on a regional or local scale. The monthly mean ozone fields show significant improvements and more detail when comparing the assimilated <span class="inline-formula">O<sub>3</sub></span> fields with the free model run, especially for features such as biomass-burning-enhanced <span class="inline-formula">O<sub>3</sub></span> concentrations and outflow of <span class="inline-formula">O<sub>3</sub></span> rich air from Asia over the Pacific.</p>https://www.atmos-chem-phys.net/19/8297/2019/acp-19-8297-2019.pdf |
| spellingShingle | J. C. A. van Peet J. C. A. van Peet R. J. van der A R. J. van der A Deriving tropospheric ozone from assimilated profiles Atmospheric Chemistry and Physics |
| title | Deriving tropospheric ozone from assimilated profiles |
| title_full | Deriving tropospheric ozone from assimilated profiles |
| title_fullStr | Deriving tropospheric ozone from assimilated profiles |
| title_full_unstemmed | Deriving tropospheric ozone from assimilated profiles |
| title_short | Deriving tropospheric ozone from assimilated profiles |
| title_sort | deriving tropospheric ozone from assimilated profiles |
| url | https://www.atmos-chem-phys.net/19/8297/2019/acp-19-8297-2019.pdf |
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