AUGUST 2005: First direct retrievals of tropospheric ozone columns from the GOME satellite instrument
The figure shows the first directly-retrieved global distributions of tropospheric column ozone from GOME satellite
UV measurements
during December 1996-November 1997, and compares to values simulated with the GEOS-CHEM global 3-D model of
atmospheric composition. The retrievals clearly show
signals due to convection, biomass burning, stratospheric influence, pollution, and
transport. They are capable of capturing regional structures such as the
1997-1998 El Nino, and synoptic-scale changes over time scales of a few days.
The
global distribution displays the well-known wave-1 pattern in the tropics, and reveals nearly zonal bands of
subtropical maxima as well as high spring-summer values at northern mid-latitudes.
Simulated values from the GEOS-CHEM model are consistent with the overall structures seen by GOME.
However, significant positive biases of 5-20 DU occur in some northern tropical and
subtropical regions such as the Middle East during summer. Comparison of GOME with
aircraft vertical profiles from the MOZAIC program usually shows good consistency.
A full description is given in Liu et al., 2005.
|