The state of the protective ozone layer over the Russian Federation territory (more than 40 years of regular observations)
This paper presents the becoming of Roshydromet ozone network and shows how it was able to achieve high quality total ozone measurements based on a simple optical instrument and become an integral part of the WMO GAW ozone network. It is shown how the method of total ozone measurements was developed, mainly used the measurements of the clear and cloudy sky zenith. This method allowed monitoring of the ozone layer state over the Russian Federation territory throughout 42 years, including the polar and subpolar area. Based on the long-term series of measurements were obtained climatic total ozone rates for 5 regions of Russia, and identified trends and trend changes in the thickness of the protective ozone layer over the vast territory of the Russian Federation.