Spatial distribution mapping of permafrost in Mongolia using TTOP

Abstract

This study presents the results of permafrost mapping in Mongolia based on the TTOP (temperature-on-top-of-permafrost) approach, which were validated against in situ measurements at various locations. In situ measurements indicated that the mean annual ground temperature (MAGT) ranged from 0.6 to 2.2 C interannually, showing the greatest variability when furthest from 0 C. The differences between the modeled and measured MAGTs exceeded ±1 C in locations where permafrost was in a nonequilibrium state and was controlled predominantly by local factors. It was estimated that permafrost occupies one-third of Mongolia. We divided the extent of the permafrost into five zones: continuous, discontinuous, sporadic, isolated, and seasonally frozen ground. In total, the permafrost zones cover $462.8 Â 10 3 km 2 , accounting for 29.3% of Mongolia. Of this total area, continuous permafrost accounted for 118.3 Â 10 3 km 2 (7.5%), discontinuous permafrost 127.7 Â 10 3 km 2 (8.1%), sporadic permafrost 112.4 Â 10 3 km 2 (7.1%), and isolated permafrost 104.4 Â 10 3 km 2 (6.6%).

Mountain Permafrost: A Reflection on the Periglacial Environment in Mongolia

“…Based on the 'Gravis Map,' the share per permafrost zone of the country's total territory in 1971 was as follows: 11.2% continuous and discontinuous, 22.4% island and sparsely island, and 29.4% sporadic [22,33,42] (Table 4). For 2013, the numbers by Jambaljav et al ( 2022) [20] were as follows: 7.5% continuous, 8.1% discontinuous, and 7.1% sporadic. Zorigt et al (2020) [38] calculated that of the total permafrost region in 2013, 33% were of continuous and 67% of discontinuous type; no other permafrost (sub-)zone was presented.…”

“…For example, when comparing the southern boundary of permafrost in Mongolia in several maps, the most extensive class that covered vast areas in 1971 but significantly receded by the 2010s was named either sporadic permafrost [22,23,31,36,42] or isolated permafrost [18,28] (Figure 5). Further-more, a comparison of results from Gravis et al (1971) [18] and Jambaljav et al (2022) [20] would reveal a change in the coverage of the continuous and discontinuous permafrost from 11.2% in 1971 to 15.6% in 2013, and a change of the sporadic permafrost coverage from 29.4% in 1971 to 7.1% in 2013. However, are these authors referring to the same zones?…”

“…Mongolia has the fifth largest permafrost area after Russia, Canada, China, and Alaska in the U.S. [20]. Sumgin (1927) [13] presented the first map of permafrost in Asia, in which the Siberian permafrost region reaches into Mongolia.…”

“…The permafrost coverage within Mongolia's territory was put at 63% in 1971 [22,30,41], 51% in 2009 [37], 29% in 2013 [20], 26% in 2013 [38]), and 29% in 2015 [29]. Based on the 'Gravis Map,' the share per permafrost zone of the country's total territory in 1971 was as follows: 11.2% continuous and discontinuous, 22.4% island and sparsely island, and 29.4% sporadic [22,33,42] (Table 4).…”

Surface temperature analysis on the eastern shore of Khuvsgul Lake

“…Гадаргын төрөл Харин FDD болон TDD утгууд нь тухайн газрын гадарга дээр зуны улиралд хэр их дулаан ирсэн болон сэрүүний улиралд хэр зэрэг хөрснийг ерөнхийд нь харуулдаг. Мөн дээрх утгуудын зөрүү нь нэмэх байх тусам газрын гадарга халалт их явагдаж цэвдэг байх нэг нөхцөл нь байхгүй болох бол хасах температуртай байх тусам тухайн газрын гадаргад хүйтний нөөц ихсэж цэвдгийн оршин тогтнох нөхцөл нэмэгддэг онцлогтой [10]. Онолын хувьд ургамал бүрхэвч багатай хээр, хуурай хээрийн ургамал зонхилсон газарт зуны улиралд халалт их явагддаг ба хүйтний улиралд цасан бүрхэвч багатай газарт бусад газраасаа илүү сэрүүн байдаг онцлогтой [4].…”