2009-05-14: Ozone hole tomography with GOME-2
The evolution and three dimensional structure of the Antarctic ozone hole can now be studied on a day-to-day basis using the latest data from the GOME-2 satellite instrument, as shown in a new study that just has been accepted for publication in Geophysical Research Letters.Van Peet et al. 2009
show that GOME-2 offers accurate vertical profiles of ozone with a high enough horizontal and vertical reolution to capture the compex dynamics of the yearly occuring phenomenon in the South Pole stratosphere. Three years after launch on the MetOp mission of EUMETSAT, GOME-2 algorithms are now in place to deliver operational data on ozone and other atmospheric trace gasses. Analysis of the data for 2008 has shown the presence of ozone depleted laminae below the ozone maximum at the edge of the Antarctic vortex, possibly caused by a combination of lower stratospheric vortex dynamics and middle and upper stratospheric transport of ozone rich air from mid-latitudes.
Time series of the ozone concentration over the Neumayer Station. Grey areas indicate missing data.
Around 26 October, air masses with elevated ozone concentrations start to appear between 50 and
20 hPa altitude and a few days later the concentrations suddenly drop by approximately a factor of two. This behavior
recurs a couple of times in the rest of the time series. The air masses with elevated ozone concentration slowly descend
during the latter half of the ozone hole period. This downward movement replenishes part of the ozone depleted air
in the Antarctic ozone hole, eventually leading to its disappearance.
North-South (top) and East-West (middle)
cross sections of ozone concentrations for 13 October 2008. Grey areas indicate missing data. In
the top plot we show the ozone concentration for constant longitude (8.26.W) with the South Pole to the left and
the North Pole to the right. The lower plot shows the cross section for constant latitude (70.65.S) with 180.W to
the left and 180.E to the right. In both plots, the location of ozone ground station Neumayer is indicated by the
arrows and the thermal tropopause (based on the climatology) has been indicated by a white line for reference.
GOME-2 total ozone columns integrated from the ozone profile retrievals (in DU) for the Southern Hemisphere (left)
and the Northern Hemisphere (right) and the exact location of the cross sections of the above figures.