RESUMO
Predicting radiative forcing due to Antarctic stratospheric ozone recovery requires detecting changes in the ozone vertical distribution. In this endeavor, the Limb Profiler of the Ozone Mapping and Profiler Suite (OMPS-LP), aboard the Suomi NPP satellite, has played a key role providing ozone profiles over Antarctica since 2011. Here, we compare ozone profiles derived from OMPS-LP data (version 2.5 algorithm) with balloon-borne ozonesondes launched from 8 Antarctic stations over the period 2012-2020. Comparisons focus on the layer from 12.5 to 27.5 km and include ozone profiles retrieved during the Sudden Stratospheric Warming (SSW) event registered in Spring 2019. We found that, over the period December-January-February-March, the root mean square error (RMSE) tends to be larger (about 20%) in the lower stratosphere (12.5-17.5 km) and smaller (about 10%) within higher layers (17.5-27.5 km). During the ozone hole season (September-October-November), RMSE values rise up to 40% within the layer from 12.5 to 22 km. Nevertheless, relative to balloon-borne measurements, the mean bias error of OMPS-derived Antarctic ozone profiles is generally lower than 0.3 ppmv, regardless of the season.
RESUMO
BACKGROUND: Over the past 15 years Punta Arenas, Chile, a medium-sized city located on the extreme southern tip of South America, has repeatedly been exposed to acute, sudden episodes of highly increased levels of ultraviolet B (UVB) 280-320 nm radiation because of the passage of the spring Antarctic "Ozone Hole" overhead, or nearby. OBJECTIVE: Our purpose was to observe the relationship between episodes of ozone depletion, increased UVB radiation, and sunburns and photosensitivity disorders in Punta Arenas, Chile, during spring. METHODS: Incidence of photosensitivity disorders and sunburns was registered by dermatologists during each of the past 15 springs. Local data of sudden, severe ozone depletions (<250 Dobson units) and the corresponding increase of UVB radiation were reviewed. RESULTS: Patients with sunburn increased significantly during the austral spring of 1999 (P <.01). This was especially noticeable (29/31 cases) on weekends with ozone depletion, and increased UVB radiation (P <.01) occurred on the Sundays Oct 31, Nov 21, and Dec 5, 1999. The incidence of photosensitivity disorders, although statistically not significant, increased 51% over the past 7 years. CONCLUSIONS: An acute impact on human health (sunburn) occurred because of abrupt ozone depletion and the accompanying increase in UVB during the mid and late austral spring of 1999. Most sunburns (93.5%) occurred on weekends. Ozone levels as well as seasonal and recreational factors played a mayor role in the increase in sunburns. The increase in radiation at 300 nm, the most carcinogenic wavelength, on days under the Antarctic ozone hole is a matter of special concern.
