[hal-00723168] Temperature profiles observed during an unusual depletion of ozone over NDACC station of Rio Gallegos (51° 55'S, 69° 14'W), Argentina on November 2009. (poster)

Since June 2005, the CEILAP group with the support of JICA (Japan International Cooperation Agency) and cooperation with French LATMOS and Japanese researches has carried out systematic measurements of ozone profile and UV radiation in the southern part of Argentina (51°55'S, 69°14'W) using a Differential Absorption lidar (DIAL), this place has been called Atmospheric Observatory of Southern Patagonia (OAPA). After 2006 other products were retrieved in addition to the ozone profiles from the DIAL measurements, such as stratospheric aerosols and temperature profiles using the off ¬wavelength signal at 355 nm. This work presents the improved algorithm used to retrieve temperature from the lidar signals and unusual temperature measurements obtained in November 9. In this work we present the incorporation of a digital filter called Savitky ¬Golay. We have evaluated the cut off frequency of the filter in relation with number of point (N) as a function of cutoff frequency. Through extensive simulations we have found a power law representative of the filter behavior. Also we have incorporated a new climatology temperature profiles database calculated from the model MSISE¬90. As a part the evaluation of this algorithm we have detected an unusual temperature profiles on November 2009 due a depletion of the ozone density. We present the comparison of these profiles measured during November 13¬14 2009, compared with the NCEP mean profiles in Río Gallegos for the period 2005¬2011. We have found a warming in the higher stratosphere with a temperature anomaly of 25 K around 36 km when the temperature profile was compared with the NCEP mean profile.



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