j@1040: Ozone Loss j@1040: ========== j@1040: j@1040: j@1040: Shown here is the chemical ozone loss in northern winter as well its j@1040: effects on mid latitudes in Europe. For example, in winter 2010/2011 j@1040: there was a very high ozone depletion in the area of the Arctic polar j@1042: vortex. In the frame of the `Knowledge Platform "Earth and Environment" (ESKP)`_ j@1040: the effects this ozone loss at mid latitudes are explained and j@1040: documented on a daily basis. An early warning system for such events j@1040: is thus established. The basis is simulations with the Jülich j@1040: chemical transport model `CLaMS`_, which uses innovative transport and j@1040: mixing algorithms to calculation of the exchange of air masses between j@1040: polar and mid Latitudes (e.g. interference of low-ozone air in j@1040: Europe). The realistic simulations are initialized by satellite j@1040: observations and driven by ECMWF meteorological analyzes. j@1040: j@1040: The ozone depletion in the polar vortex is determined by the j@1040: temperature. For polar ozone loss, the temperature must drop below a j@1040: threshold of approximately -78°C. For the Arctic winters of 2010-2020 j@1040: the `Calculations of ozone loss`_ and `Estimates from temperature`_ j@1040: are shown. To explain and assess the results, it is also explained j@1040: how the `UV increase`_ on the ground develops in the course of spring j@1040: for the case of different ozone losses. Calculated ozone loss and j@1040: ozone column as well as the calculated from it maximum UV index (at j@1040: noon with a clear sky) are considered `Map display`_ shown for the j@1040: individual days. j@1040: j@1040: Typically, the ozone columns in the Arctic are still higher than in j@1040: the Antarctic despite ozone depletion, so that in the Arctic spring j@1040: there is so far at most a moderate UV radiation at the ground. j@1040: j@1040: Current j@1040: -------- j@1301: In contrast to the previous winter, **the current winter 2021/2022** j@1301: so far shows rather low stratospheric temperatures. There is therefore j@1301: again the possibility of strong ozone depletion. j@1040: j@1410: In contrast to the previous winter, **the current winter 2021/2022** j@1410: again shows very low stratospheric temperatures. The ozone depletion j@1410: is very significant, already above 80 DU. However, this is not quite j@1410: as much as in the largest Arctic ozone depletion so far in the year j@1410: 2020. j@1410: j@1410: j@1040: j@1040: Previous years j@1040: -------------- j@1040: j@1301: In recent years, the winters 2010/2011, 2015/2016, and 2019/2020 were particularly j@1040: noteworthy, as they were characterized by a cold, stable polar vortex, j@1040: which with clear corresponding ozone depletion. This yielded only a j@1040: slight increase in UV radiation, which is typically low in our j@1040: latitudes in March. Extremely high UV values ​​like in the Antarctic j@1040: spring under the ozone hole did not occur so far in the Arctic. j@1040: j@1040: j@1301: j@1301: Winter 2019/2020: j@1301: ----------------- j@1301: The stratospheric temperatures in the winter of 2019/2020 were again j@1301: very low and the polar vortex was stable for a very long time. Both factors j@1301: led to the largest Arctic ozone loss to date. In the meantime j@1301: this is extensively documented in the scientific literature (`1`_, `2`_). j@1301: j@1301: j@1040: Winter 2015/2016: j@1040: ----------------- j@1040: The stratospheric temperatures in winter 2015/2016 were as low as j@1040: never seen in recent decades before with the result of a very high j@1040: ozone loss of over 100 DU. The lower ozone columns resulted in a j@1040: slight increase in UV radiation on the ground. However, the UV j@1040: radiation is in these latitudes is low at this time of year. When j@1040: these air masses of the polar vortex moved towards mid-latitudes, the j@1040: UV index in early March is as high as normally expected in late j@1040: March. Extremely high UV values ​​as in the Antarctic spring under the j@1040: ozone hole did not yet occur in the Arctic. j@1040: j@1040: j@1040: Winter 2010/2011: j@1040: ----------------- j@1040: The images below show the geographical distribution of the calculated j@1040: ozone column (top) and ozone loss (bottom) for March 28, 2011. Shown j@1040: is the total column between 12 and 22 km altitude in Dobson Units (DU). j@1040: j@1040: .. _Calculations of ozone loss: /ozoneloss/clams/2020 j@1040: .. _Estimates from temperature: /ozoneloss/vpsc/2020 j@1040: .. _UV increase: /ozoneloss/uvi j@1040: .. _Map display: /ozoneloss/uvmap/200119 j@1042: .. _Knowledge Platform "Earth and Environment" (ESKP): /eskp j@1040: .. _CLaMS: http://en.wikipedia.org/wiki/CLaMS