First ozone-hole event over Ushuaia in 2010 (September 17, 2010)

On September 17, just after the Day for the Preservation of the Ozone Layer (September 16), the first signature of ozone hole over Ushuaia in 2010 has been recorded.

Vertical profiles of temperature and ozone on September 17 are shown in the graphic. Low ozone values (below 5 mPa) have been recorded between 17 and 20 km, where chemically-induced ozone destruction can be observed. These values are
coincident with very low temperatures (below -80ºC), below the temperature of nitric acid trihydrate (NAT) particles formation. Total column ozone for this day was 208 Dobson Units (DU) as recorded by the ECC ozonesonde. The Dobson spectrophotometer at Ushuaia confirmed the low ozone values with a record of 218 DU, lower than 220 DU, the threshold of ozone-hole event. On September 15 the ozonesonde profile recorded 339 DU when Ushuaia was out of the polar vortex influence.  The maximum Ultraviolet index (UVI) values recorded by our NILU radiometer at Ushuaia on September 15 and 17, was 2.0 and 3.4, respectively.

The ozonesonde launching on September 17 was performed because the Temis forecast warned us that Ushuaia would be under the influence of the ozone hole. That was a successful forecasting. This is a very good example of ozone depleted air affecting a region outside out Antarctica. You can follow daily ozone-hole forecasts at  www.temis.nl

The ozonesonde program carried out at the Ushuaia Global GAW station is a joint project of the National Meteorological Service (SMN, Argentina), the Government of Tierra del Fuego (Argentina), the National Institute for Aerospace Technology (INTA, Spain) and the Meteorological State Agency (AEMET, Spain). We thank Manuel Cupeiro, Ricardo Sanchez (SMN) and the Ushuaia team for their very nice job with the ozonesonde program.

Ozone hole forecast by TEMIS (MACC-ECMWF) for September 17, 2010.