Temporal-spatial variability of modern climate in the Altai Mountains during 1970-2015

ecosystems [28–31]. They have the largest unbroken stretches of Siberian fir, pine and larch trees in the world. The particularly remarkable species is dark coniferous taiga. Glaciers mainly occupy in the central part of Altai Mountains, especially on the ranges of Katunsky, Taldur- insky, Ak-Turu, Munku-Sardyk, South and North Chuisky, Kryzin [32–37]. They give life to two largest rivers (e.g., Ob and Yenisei river) and several large lakes (e.g., Khuvsgul, Uvs, Tele- tskoe and Wulungu lake). The climate in the Altai Mountains is featured by the harsh conti- nental climate [31–37]. Due to the most of humid air masses transported by the westerlies from the west throughout a year, the Altai Mountains are featured by a strong northwest to southeast precipitation gradient [38–39]. The Siberian High controls the cold-season climate and prevents precipitation formation in the Altai Mountains [26–27, 38, 40]. Data resource and method Data resource The selected stations were showed in the Altai Mountains in Fig 1 and their detailed informa- tion was showed in Table 1. The eight stations are situated in the Russian Altai Mountains and they are Zmeinogorsk, Soloneshnoe, Kyzyl-Ozek, Yailu, Mugur-Aksy, Ust-Coksa, Kara- Tyurek and Kosh-Agach. The three stations are located in the Mongolian Altai Mountains and they are Olgyi, Yalalt, Khovd. The four stations are situated in the Chinese Altai Mountains and they are Habahe, Aletai, Fuyun and Qinghe. The data from Russia was obtained from the website (http://meteo.ru/english/data/) and the data from Mongolia was provided by Dr. Mar-

iia Andreeva. The data from China was downloaded from the website (http://cma.gov.cn). These meteorological data from three countries was both pre-disposed through the strict qual- ity control and homogenized. The data from Semipalatinsk and Zajsan meteorological station within Kazakhstan was selected and was just for calculating seasonal features of temperature and precipitation because of no long time-scale observed data. The seasonal changes were also taken into account and spring is from March to May, summer is from June to August, autumn is from September to November, and winter is from December to February in the next year. Table 1. Related information of meteorological stations in the Altai Mountains. No. Station Name Latitude (˚N) Longitude (˚E) Altitude (m) Annual temperature (˚C) Annual precipitation (mm) Interval 1 Zmeinogorsk 51.15 82.17 354 2.81 692.78 1966–2016 2 Soloneshnoe 51.63 84.33 409 1.86 581.20 1966–2016 3 Kyzyl-Ozek 51.90 86.00 331 2.07 745.00 1966–2016 4 Yailu 51.77 87.60 480 3.73 894.95 1966–2016 5 Mugur-Aksy 50.38 90.43 1850 -2.36 142.60 1966–2016 6 Ust-Coksa 50.30 85.60 978 0.62 472.23 1940–2017 7 Kara-Tyurek 50.00 86.40 2600 -5.54 601.41 1940–2017 8 Kosh-Agach 50.00 88.04 1760 -4.96 119.93 1936–2017 9 Yalalt 48.80 89.50 2148 2.75 134.16 1970–2015 10 Olgiy 48.96 89.98 1715 1.23 111.08 1961–2015 11 Khovd 48.08 91.35 1405 1.24 132.85 1961–2015 12 Qinghe 46.67 90.38 1220 0.72 125.01 1958–2017 13 Fuyun 46.98 89.52 826.6 2.88 177.71 1962–2017

14 Aletai 47.73 88.08 736.9 4.48 190.13 1958–2017 15 Habahe 48.05 86.40 534 4.77 199.93 1958–2017 16 Zajsan 47.47 84.92 603 4.12 294.53 1967–2000 17 Semipalatinsk 50.42 80.30 196 3.58 285.66 1940–2011 https://doi.org/10.1371/journal.pone.0230196.t001 PLOS ONE Modern climate characters in the Altai Mountains PLOS ONE | https://doi.org/10.1371/journal.pone.0230196 March 17, 2020 3 / 15