The effect of climate change on the upper stratospheric ozone depletion from Umkehr measurements over Antarctica

第１回極域科学シンポジウム「極域大気圏を通して探る地球規模環境変動」ポスター発

Long term changes in the upper stratospheric ozone at Syowa, Antarctica

第2回極域科学シンポジウム/第35回極域宙空圏シンポジウム 11月15日（火） 国立極地研究所 2階大会議

Ozone recovery in the upper stratosphere from Umkehr measurement over Syowa, Antarctica

第3回極域科学シンポジウム/第35回極域気水圏シンポジウム 11月30日（金） 国立国語研究所 ２階ロビ

Inspection and assessment of concrete pipe culverts under highways in Tatarstan

The experience of examining small culverts of artificial structures, carried out by a number of specialized organizations, shows that on some highways of the country up to 80% of pipes have some degree of damage. This article provides data from field surveys of pipes located on the main highways of Tatarstan. Survey data is needed to identify common problems at concrete culverts in Tatarstan. Field data were also analyzed using statistical software to identify factors contributing to the degradation of concrete culverts. The article presents a method for assessing the risk of developing negative phenomena when maintaining concrete pipes. The proposed risk assessment method allows predicting and preventing the occurrence of such phenomena

What controls long-term Ozone changes other than Ozone-Depleting Substances in the Antarctic stratosphere?

In the upper stratosphere the inter-annual variability of ozone is mostly controlled by chemical reactions and is strongly influenced by the anthropogenic ozone-depleting substances (ODS). While at middle latitudes the ODS reached the maximum in the stratosphere by the end of 1990s, at high latitudes the turning in the growth rate of the ODS has been delayed by several years. Analysis of Umkehr observations helps to understand the influence of the ODS on ozone in the middle and upper stratosphere. We investigated the long-term trend in the upper stratospheric ozone over the Antarctic using re-processed Umkehr data at Syowa station (69.0 S, 39.5 E). The long-term variability and trend observed in Umkehr ozone profile data is in good agreement with the station’s overpass subset of the SBUV V8.6 Merged Ozone Dataset. The long-term trend is affected by the changes in the polar vortex position and its persistence relative to the geophysical location of Syowa station. We have found a high correlation between the Equivalent Latitude (EqLat) at 850K (10 hPa or 32 km) and stratospheric ozone. The Southern Hemisphere Annular Mode (SAM) is also considered as one of the explanatory parameters in our analysis of ozone variability over Syowa. High correlation is found between stratospheric ozone and SAM during high solar activity years (HS, 1978-1982, 1988-1992, and 1998-2002). The largest variability in the Antarctic stratosphere related to the SAM signal is observed from September to December. Since the SAM and upper stratospheric ozone are both affected by planetary wave propagation, their correlation reflects their response to the same mechanism, especially during HS.In this presentation, we describe attribution of ozone variability to the proxies and discuss differences in factors that affect upper, middle and lower stratospheric ozone over Syowa.第4回極域科学シンポジウム個別セッション：[OM] 気水圏11月14日（木） 統計数理研究所 ３階セミナー室１（D305

The Network for the Detection of Atmospheric Composition Change (NDACC): history, status and perspectives

The Network for the Detection of Atmospheric Composition Change (NDACC) is an international global network of more than 90 stations making high-quality measurements of atmospheric composition that began official operations in 1991 after 5 years of planning. Apart from sonde measurements, all measurements in the network are performed by ground-based remote-sensing techniques. Originally named the Network for the Detection of Stratospheric Change (NDSC), the name of the network was changed to NDACC in 2005 to better reflect the expanded scope of its measurements. The primary goal of NDACC is to establish long-term databases for detecting changes and trends in the chemical and physical state of the atmosphere (mesosphere, stratosphere, and troposphere) and to assess the coupling of such changes with climate and air quality. NDACC's origins, station locations, organizational structure, and data archiving are described. NDACC is structured around categories of ground-based observational techniques (sonde, lidar, microwave radiometers, Fourier-transform infrared, UV-visible DOAS (differential optical absorption spectroscopy)-type, and Dobson–Brewer spectrometers, as well as spectral UV radiometers), timely cross-cutting themes (ozone, water vapour, measurement strategies, cross-network data integration), satellite measurement systems, and theory and analyses. Participation in NDACC requires compliance with strict measurement and data protocols to ensure that the network data are of high and consistent quality. To widen its scope, NDACC has established formal collaborative agreements with eight other cooperating networks and Global Atmosphere Watch (GAW). A brief history is provided, major accomplishments of NDACC during its first 25 years of operation are reviewed, and a forward-looking perspective is presented

Formation of a comfortable transport infrastructure for cyclist traffic in the tourist area of Kazan

This article examines the issue of cycling in Russian cities on the example of the city of Kazan. The authors come to the conclusion that the existing bicycle zones in Kazan aren’t connected to each other and don’t intersect complex transport hubs with high traffic intensity, therefore, cycling around the city isn’t safe and comfortable. As a solution to this problem, the idea of a new combined overpass, combining a pedestrian and roadway for cyclists, is presented. In addition, it’s proposed to develop the street and road network of the city of Kazan, through the construction of new bicycle paths. The combined overpass will allow for a more rational redirection of the city's traffic flows, ensure the safety of high-speed traffic and create comfortable conditions for the city's population. The construction of a bicycle path will reduce the total traffic load on the city's roads, and ensure safe movement for citizens in the central part of the city. Thus, the need to introduce and develop bicycling in our city, which entails planning not only bicycle paths, but also the construction of other transport infrastructure facilities for comfortable crossing of transport hubs with high traffic intensity by cyclists, seems obvious

Updated trends of the stratospheric ozone vertical distribution in the 60 degrees S-60 degrees N latitude range based on the LOTUS regression model

This study presents an updated evaluation of stratospheric ozone profile trends in the 60∘&thinsp;S&ndash;60∘&thinsp;N latitude range over the 2000&ndash;2020 period using an updated version of the Long-term Ozone Trends and Uncertainties in the Stratosphere (LOTUS) regression model that was used to evaluate such trends up to 2016 for the last WMO Ozone Assessment (2018). In addition to the derivation of detailed trends as a function of latitude and vertical coordinates, the regressions are performed with the datasets averaged over broad latitude bands, i.e. 60&ndash;35∘&thinsp;S, 20∘&thinsp;S&ndash;20∘&thinsp;N and 35&ndash;60∘&thinsp;N. The same methodology as in the last assessment is applied to combine trends in these broad latitude bands in order to compare the results with the previous studies. Longitudinally resolved merged satellite records are also considered in order to provide a better comparison with trends retrieved from ground-based records, e.g. lidar, ozonesondes, Umkehr, microwave and Fourier transform infrared (FTIR) spectrometers at selected stations where long-term time series are available. The study includes a comparison with trends derived from the REF-C2 simulations of the Chemistry Climate Model Initiative (CCMI-1). This work confirms past results showing an ozone increase in the upper stratosphere, which is now significant in the three broad latitude bands. The increase is largest in the Northern and Southern Hemisphere midlatitudes, with &sim;2.2&thinsp;&plusmn;&thinsp;0.7&thinsp;% per decade at &sim;2.1&thinsp;hPa and &sim;2.1&thinsp;&plusmn;&thinsp;0.6&thinsp;% per decade at &sim;3.2&thinsp;hPa respectively compared to &sim;1.6&thinsp;&plusmn;&thinsp;0.6&thinsp;% per decade at &sim;2.6&thinsp;hPa in the tropics. New trend signals have emerged from the records, such as a significant decrease in ozone in the tropics around 35&thinsp;hPa and a non-significant increase in ozone in the southern midlatitudes at about 20&thinsp;hPa. Non-significant negative ozone trends are derived in the lowermost stratosphere, with the most pronounced trends in the tropics. While a very good agreement is obtained between trends from merged satellite records and the CCMI-1 REF-C2 simulation in the upper stratosphere, observed negative trends in the lower stratosphere are not reproduced by models at southern and, in particular, at northern midlatitudes, where models report an ozone increase. However, the lower-stratospheric trend uncertainties are quite large, for both measured and modelled trends. Finally, 2000&ndash;2020 stratospheric ozone trends derived from the ground-based and longitudinally resolved satellite records are in reasonable agreement over the European Alpine and tropical regions, while at the Lauder station in the Southern Hemisphere midlatitudes they show some differences. &nbsp;</p

Retrieving vertical ozone profiles from measurements of global spectral irradiance

A new method is presented to determine vertical ozone profiles from measurements of spectral global (direct Sun plus upper hemisphere) irradiance in the ultraviolet. The method is similar to the widely used Umkehr technique, which inverts measurements of zenith sky radiance. The procedure was applied to measurements of a high-resolution spectroradiometer installed near the centre of the Greenland ice sheet. Retrieved profiles were validated with balloonsonde observations and ozone profiles from the space-borne Microwave Limb Sounder (MLS). Depending on altitude, the bias between retrieval results presented in this paper and MLS observations ranges between -5 and + 3 %. The magnitude of this bias is comparable, if not smaller, to values reported in the literature for the standard Dobson Umkehr method. Total ozone columns (TOCs) calculated from the retrieved profiles agree to within 0.7 +/- 2.0% (+/- 1 sigma) with TOCs measured by the Ozone Monitoring Instrument on board the Aura satellite. The new method is called the "Global-Umkehr" method

Optimizing Umkehr Ozone Profile Retrievals

NOAA Dobson Umkehr ozone profile records have been collected since the 1970s. Umkehr ozone profiles are used to monitor stratospheric ozone recovery predicted to occur by the 2050s. Current operational Dobson Umkehr profile algorithms produce data that have uncertainty on the order of ~ 5 % in the stratosphere. However, when large volcanic eruptions inject aerosols into the stratosphere, the errors can be as large as 70 %. In order to evaluate Umkehr records for aerosol-related and instrumental artifacts, we compare observations with a Hindcast simulation of the NASA Merra-2 Global Modeling Initiative (GMI) Replay (M2GMI, Orbe et al, 2017; Wargan et al, 2018) and Chemistry Transport Model (GMI CTM, Strahan et al, 2013, Strahan et al, 2016). The biases found between the models and observations are summarized for each Dobson calibration and volcanic eruption period, thus providing a reference tool for homogenization of the Umkehr time series and removal of volcanic aerosol errors