Open AccessGlobal tropospheric NO 2 column distributions: Comparing three‐dimensional model calculations with GOME measurements
Author(s) -
Velders Guus J. M.,
Granier Claire,
Portmann Robert W.,
Pfeilsticker Klaus,
Wenig Mark,
Wagner Thomas,
Platt Ulrich,
Richter Andreas,
Burrows John P.
Publication year - 2001
Publication title -
journal of geophysical research: atmospheres
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2000jd900762
Subject(s) - troposphere , tropospheric ozone , column (typography) , environmental science , atmospheric sciences , satellite , planetary boundary layer , chemical transport model , meteorology , climatology , geology , mathematics , geometry , physics , connection (principal bundle) , astronomy , turbulence
Tropospheric NO 2 columns derived from the data products of the Global Ozone Monitoring Experiment (GOME), deployed on the ESA ERS‐2 satellite, have been compared with model calculations from two global three‐dimensional chemistry transport models, IMAGES and MOZART. The main objectives of the study are an analysis of the tropospheric NO 2 data derived from satellite measurements, an interpretation of it and evaluation of its quality using global models, and an estimation the role of NO 2 in radiative forcing. The measured and modeled NO 2 columns show similar spatial and seasonal patterns, with large tropospheric column amounts over industrialized areas and small column amounts over remote areas. The comparison of the absolute values of the measured and modeled tropospheric column amounts are particularly dependent upon uncertainties in the derivation of the tropospheric NO 2 columns from GOME and the difficulty of modeling the boundary layer in global models, both of which are discussed below. The measured tropospheric column amounts derived from GOME data are of the same order as those calculated by the MOZART model over the industrialized areas of the United States and Europe, but a factor of 2–3 larger for Asia. The modeled tropospheric NO 2 columns from MOZART as well as the column amounts measured by GOME are in good agreement with NO 2 columns derived from observed NO 2 mixing ratios in the boundary layer in eastern North America. The comparison of the models to the GOME data illustrates the degree to which present models reproduce the hot spots seen in the GOME data. The radiative forcing of NO 2 has been estimated from the calculated tropospheric NO 2 columns. The local maxima in the radiative forcing of tropospheric NO 2 for cloud‐free conditions over the eastern United States and western Europe represent 0.1–0.15 W m −2 , while values of 0.04–0.1 W m −2 are estimated on a continental scale in these regions, of the same order of magnitude as the forcing of N 2 O and somewhat smaller than the regional forcing of tropospheric ozone. The globally averaged radiative forcing of tropospheric NO 2 is negligible, ∼0.005 W m −2 .