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Titel |
Impacts of different plant functional types on ambient ozone predictions in the Seoul Metropolitan Areas (SMAs), Korea |
VerfasserIn |
H.-K. Kim, J.-H. Woo, R. S. Park, C. H. Song, J.-H. Kim, S.-J. Ban, J.-H. Park |
Medientyp |
Artikel
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Sprache |
Englisch
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ISSN |
1680-7316
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Digitales Dokument |
URL |
Erschienen |
In: Atmospheric Chemistry and Physics ; 14, no. 14 ; Nr. 14, no. 14 (2014-07-22), S.7461-7484 |
Datensatznummer |
250118901
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Publikation (Nr.) |
copernicus.org/acp-14-7461-2014.pdf |
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Zusammenfassung |
Plant functional type (PFT) distributions affect the results of biogenic
emission modeling as well as O3 and particulate matter (PM) simulations using
chemistry-transport models (CTMs). This paper analyzes the variations of
both surface biogenic volatile organic compound (BVOC) emissions and O3 concentrations due to
changes in the PFT distributions in the Seoul Metropolitan Areas, Korea.
The Fifth-Generation NCAR/Pennsylvania State Meso-scale Model (MM5)/the Model of
Emissions of Gases and Aerosols from Nature (MEGAN)/the Sparse Matrix Operator
Kernel Emissions (SMOKE)/the Community Multiscale Air Quality (CMAQ)
model simulations were implemented over the Seoul
Metropolitan Areas in Korea to predict surface O3 concentrations for the
period of 1 May to 31 June 2008. Starting from a performance check of CTM
predictions, we consecutively assessed the effects of PFT area deviations on
the MEGAN BVOC and CTM O3 predictions, and we further considered the
basis of geospatial and statistical analyses. The three PFT data sets
considered were (1) the Korean PFT, developed with Korea-specific vegetation
database; (2) the CDP PFT, adopted from the community data portal (CDP) of US
National Center for Atmospheric Research in the United States (NCAR); (3)
MODIS PFT, reclassified from the NASA Terra and Aqua combined land cover
products. Although the CMAQ performance check reveals that all of the three
different PFT data sets are applicable choices for regulatory modeling
practice, noticeable primary data (i.e., PFT and Leaf Area Index (LAI)) was
observed to be missing in many geographic locations. Based on the assessed
effect of such missing data on CMAQ O3 predictions, we found that this
missing data can cause spatially increased bias in CMAQ O3. Thus, it
must be resolved in the near future to obtain more accurate biogenic emission
and chemistry transport modeling results.
Comparisons of MEGAN biogenic emission results with the three different PFT
data showed that broadleaf trees (BTs) are the most significant contributor,
followed by needleleaf trees (NTs), shrub (SB), and herbaceous plants (HBs)
to the total BVOCs. In addition, isoprene from BTs and terpene from NTs were
recognized as significant primary and secondary BVOC species in terms of BVOC
emissions distributions and O3-forming potentials in the study domain. A
geographically weighted regression analysis with locally compensated ridge
(LCR-GWR) with the different PFT data (δO3 vs. δPFTs)
suggests that addition of BT, SB, and NT areas can contribute to O3
increase, whereas addition of an HB area contributes to O3 decrease in
the domain.
Assessment results of the simulated spatial and temporal changes of O3
distributions with the different PFT scenarios reveal that hourly and local
impacts from the different PFT distributions on occasional inter-deviations
of O3 are quite noticeable, reaching up to 13 ppb. The simulated
maximum 1 h O3 inter-deviations between different PFT scenarios have an
asymmetric diurnal distribution pattern (low in the early morning,
rising during the day, peaking at 05:00 p.m., and decreasing during the
night) in the study domain. Exponentially diverging hourly BVOC emissions
and O3 concentrations with increasing ambient temperature suggest that
the use of different PFT distribution data requires much caution when modeling (or forecasting) O3
air quality in complicated urban atmospheric conditions in terms of whether uncertainties in O3 prediction results
are expected to be mild or severe. |
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