WMO Aeronautical Meteorology Scientific Conference 2017

6 - 10 November 2017

Centre International de Conférences - Météo-France - Toulouse - France

Session 3 – Impacts of climate change and variability on aviation operations and associated science requirements 3.2 – Extreme weather events at , changes to established scenarios

On variation of several climatological characteristics at aerodromes in the Russian Federation in 2001-2015

Anna Ivanova, Hydrometeorological Research Centre of the Russian Federation [email protected] ------co-authors: Elena Skriptunova ------speaker: Anna Ivanova

The aeronautical climatological information required for the planning of flight operations should be prepared in the form of aerodrome climatological tables and aerodrome climatological summaries [1,2]. Amongst others, these tables and summaries contain the data on average and extreme values of temperature, QNH, on the occurrence frequency and duration of significant weather affecting airplane landing, take-off and terminal services operations. Depending on terminal location such weather phenomena as fog, blizzard, icing, dust storm, thunderstorm etc may be considered as significant weather. According to ICAO recommendation, a eronautical climatological information should be based on the observations performed during at least 5-year period [2]. Automated systems for acquisition, collecting, storage of information are installed not in every Russian just yet. It makes difficult a renewing of climatological information and an analysis of its variation. In this investigation we attempted to evaluate the possible climatic changes at Russian aerodromes based on METAR data archive for the period between 2001-2015. The archive was collected in the Aeronautical Meteorology Department of Hydrometeorological Research Centre of the Russian Federation. The observations at 51 large international airports were analyzed (26 in the European part, EPR, and 25 – in the Asian part of , APR). On the basis of hourly (half-hourly) terminal observation data between 2001-2015, some variations of several parameters from aeronautical climatological description were studied. The purpose of the study was to analyze the occurrence frequency and duration of significant weather as far as special ranges for temperature and wind parameters. The stated characteristics have been calculated for three consecutive 5-year periods (2001-2005, 2006-2010, 2011-2015), i.e. the minimum periods to get aeronautical climatological information. It was important to detect the monotonic trends for occurrence frequency of some parameters and to study an interannual variation of extreme values for several atmosphere parameters (temperature, wind speed and gusts, QNH).

WMO Aeronautical Meteorology Scientific Conference 2017

6 - 10 November 2017

Centre International de Conférences - Météo-France - Toulouse - France

Impact of temperature on take-off and landing should be considered particularly for extreme value. Very low temperatures (below -30 0C) make aerodrome operations difficult, 0 leading to cancelation or delay of many flights . At high temperatures (as a rule, above +30 C) the takeoff parameters (from Aircraft Flight Manual) are restricted. Air density decreases under increased temperature, therefore, an ascensional power generated on takeoff decreases too. For this reason the aircraft weight restrictions arise [3]. For each of the 51 aerodromes yearly the extreme values for maximum and minimum temperature have been analyzed. It was found that there were no trends for temperature extremes at each aerodrome. However, 15-year period is rather a short time distance to evaluate climate change effect. Therefore, it is important to clarify, how global warming trend is expressed as absolute extreme values of temperature. International airports, as a rule, are located close to settlements where meteorological observations have been made for many years. On the basis of this information, the places with temperature extreme values overtopping in the 21 st century have been found. It was detected that the temperature absolute maxima were renewed in the most part of the European part of Russia. At the same time, in the early 21 st century some absolute minima of temperature were renewed (in the south of the EPR; in the APR – in Barnaul, Khabarovsk, Tiksi). On the basis of terminal data during three consequential 5-year periods, the occurrence frequency of days with Т≥+30 0С and Т≤–30 0С (conditionally named as “hot” and “very cold”) is investigated. Hot and very cold day variations occur more often in the Asian part of Russia. Increase of number of days with Т≥+30 0С was observed in western area of the APR mainly. By contrast, the decrease of hot days as well as the increase of very cold days occurred in Eastern Siberia. Number of days with wind speed value more than 10 m/s, ND, and number of reports with wind gust value more than 15 m/s, NR, were studied. Monotonic trends of ND and NR were detected at 31% and 21% Russian aerodromes , respectively, spatial distribution of trend signs for ND and NR was rather varied. Both, ND and NR positive trends were observed in (UEEE) in the APR and in Rostov-on-Don (URRR) in the EPR. There were no QNH trends at the Russian aerodromes between 2001-2015. Absolute maximum of QNH – 1068 hPa – was recorded at Novosibirsk aerodrome (UNNT) in 2010, absolute minimum – 952 hPa – was at Syktyvkar aerodrome (UUYY) in 2011. As for significant weather , the event duration and ND (for fog, blizzard, thunderstorm, glaze, squalls, tornado) were studied. Maximum fog duration in the EPR was registered in Saratov airport for 77 hours. The most long-term event of fog in the APR were

WMO Aeronautical Meteorology Scientific Conference 2017

6 - 10 November 2017

Centre International de Conférences - Météo-France - Toulouse - France observed in (165 h in January 2006). In 2001-2015, the fog frequency decreased mainly at EPR aerodromes (in (UUWW,UUDD), Syktyvkar (UUYY), St.- Petersburg (ULLI), Volgograd (URWW), Astrakhan(URWA)), as well as at aerodromes in East Siberia (Tiksi (UEST), Yakutsk (UEEE), Ulan-Ude (UIUU)). Increase of fog occurrence frequency was typical for West Siberia and Southern Ural (Fig.1,a). At the same time, the average fog event duration increased at some aerodromes of Volga region (URWW,URWA), in Vnukovo (UUWW, Moscow), Pulkovo (ULLI, St.-Petersburg) and at aerodromes of Yakutiya (UEEE and UEST, for UEEE – by an average 2.5 h). In (UULI) near St.-Petersburg both average and maximum fog event duration increased. Trends of ND with blizzard leading to visibility down in cold months occurred at 43% of all aerodromes, the trends were predominantly negative (Fig.1,b). The most significant negative trend was detected at aerodromes of the EPR, especially in Domodedovo (UUDD) and in Syktyvkar (UUYY) – 4.5-fold and 3.1-fold respectively. Positive trends of ND with blizzard were registered at just three aerodromes – in Stavropol (URMT), Nikolaevsk-on-Amur (UHNN) and Kemerovo (UNEE). Glaze can negatively affect takeoff and landing because of decrease of runway surface friction and increase of aircraft weight. Glaze is caused by freezing precipitation (FP), its occurrence leads to flight delays due to runway snow removal and aircraft deicing procedures. Maximum FP occurrence frequency and maximum FP duration (68h) were observed in the EPR in airport (URMM). Monotonic trends of FP episodes between 2001-2015 were recorded mainly at the aerodromes of the EPR (Fig.1,c), these trends were predominantly negative except for aerodromes Simferopol (URFF) and Stavropol (URMT) in the southern part. Thunderstorm is a hazardous weather for aircraft for all phases of its flight. Apart from that, an approach of thunderstorm leads to revise of airport activities. Figure 1,d shows mainly a decrease of ND with thunderstorm at aerodromes of the EPR. Nevertheless, two Moscow aerodromes with the highest capacity – Sheremetyevo (UUEE) and Domodedovo (UUDD) – were characterized by some increase of ND with thunderstorm – 1.3-fold and 1.2-fold, respectively. The most growth of thunderstorm occurrence frequency was detected in Surgut (USRR) – 4.2-fold. The most decrease of ND with thunderstorm occurred in Vladivostok (UHWW) and in Rostov-on-Don (URRR): 9- and 7-fold respectively. As very hazardous weather as tornado is , was considered outside of other significant weather. Tornado can be experienced typical for vicinity of Sochi aerodrome (URSS) only, but not every year. The number of tornado events has reduced in the last few years (2 events in 2011-2015 vs 19 in 2006-2010 and 16 in 2001-2005).

WMO Aeronautical Meteorology Scientific Conference 2017

6 - 10 November 2017

Centre International de Conférences - Météo-France - Toulouse - France

Occurrence frequency of squalls (typically “in vicinity” too) was much more. Maximum number of squalls was observed in the south of the European part of Russia. So, at aerodrome Simferopol (URSS) 45 squalls were registered between 2001-2015 (25 of them – in 2006- 2010). Most long-term periods with squalls, accompanying very intense thunderstorms, were registered at Nizhniy Novgorod (UWGG) aerodrome, especially in 2006 (in June, 18 the squalls were detected every half-hour for 7 h, in September, 2 – for 4.5 h).

ULMM ULMM

UEST UEST ULLI ULLA UHMM ULLI ULLA UHMM UOOO UOOO UUEE UUYY USDD UUEE UUYY USDD UUDD UEEE UUDD UEEE UUWW UUWW UWGG UERR UWGG UERR UWKD UHNN UWKD UUOO UWLL USRR UUOO UWLL USRR UHNN UWKE USSS UELL UWKE USSS URFF URRR UWSS UWWW URFF UWSS UELL USTR URRR UWWW USTR URKA URWW UWUU USCC URKA URWW UWUU URKK UNOO UHSS URKK USCC UHSS UNEE UNKL UIBB UHHH UNOO UIBB URMT UHBB URMT UNEE UNKL UHBB UHHH URSS URWA UNNT URSS URWA UNNT URMM UNAA UIAA UNAA UIAA UNBB UIII URMM UNBB UIII UNWW UIUU UNWW UIUU UHWW a b UHWW

ULMM ULMM

UEST UEST ULLI ULLI ULLA UHMM ULLA UHMM UOOO UOOO UUEE UUYY USDD UUEE UUYY USDD UUDD UEEE UUDD UEEE UUWW UUWW UWGG UERR UWGG UERR UWKD UWKD UHNN UUOO UWLL USRR UHNN UUOO UWLL USRR UWKE UWKE USSS URFF UWSS USSS UELL URFF UWSS UELL URRR UWWW URRR UWWW USTR USTR URKA UWUU URKA URWW UWUU USCC URWW USCC UHSS URKK UHSS URKK UNOO UNOO UIBB UNEE UNKL UIBB UHHH URMT UNEE UNKL UHBB UHHH URMT UHBB URSS URWA UNNT URSS URWA UNNT UNAA UIAA URMM UNAA UIAA URMM UNBB UIII UNBB UIII UNWW UNWW UIUU UIUU UHWW c UHWW d

Figure 1. Trends (red is positive, blue is negative) in occurrence frequency of ND with a) fog, b) blizzard, c) freezing precipitation d) thunderstorm at aerodromes of the Russian Federation between 2001-2015.

Summarizing the above, one can conclude as follows. According to research, monotonic trends (of some atmosphere parameters or of significant weather frequency) occurred at ~25- 40% aerodromes, more often – located in the European part of Russia. On the whole, at each aerodrome of the EPR, except for Anapa (URKA) and Sochi (URSS), at least one of similar trends was observed. In accordance with global climate change, a decrease of hot days at some aerodromes as well as an increase of very cold days at others was detected between 2001-2015. The change of wind conditions at Russian aerodromes was characterized by heterogeneity. As for significant weather for landing, take-off, and terminal services

WMO Aeronautical Meteorology Scientific Conference 2017

6 - 10 November 2017

Centre International de Conférences - Météo-France - Toulouse - France operations (apart from thunderstorms), one can observe mainly negative trends of its occurrence frequency, especially in the European part of Russia. One can record multiple climatic variations at some aerodromes. So, at the Moscow aerodrome Domodedovo (UUDD) occurrence frequency of thunderstorm increased, at the same time the occurrence frequencies of fogs, blizzard and freezing precipitation decreased. At Yakutsk aerodrome (UEEE), apart from renewing of absolute temperature maximum in 2011, the number of very cold days increased as well as occurrence frequency of days with thunderstorms and with wind speed ≥10 m/s. The number of days with fog decreased here, but the fog duration was up by ~2 h. One can note the decrease of occurrence frequency of fog, blizzard, thunderstorm at aerodromes near St-Petersburg (ULLI) and Ulan-Ude (UIUU).

Referencies: 1. Technical Regulations. Basic documents No 2. Volume II – Meteorological Service for International Air Navigation – WMO-No.49, 2013 edition. 2. Meteorological Service for International Air Navigation – Annex 3 to the Convention on International Civil Aviation Nineteenth Edition, July 2016. 3. Coffel E., Horton R. Climate change and the impact of extreme temperature on aviation. – Weather. Climate and Society, 2015, vol.7, pp.94-102.