## 1 Introduction  
Observed and predicted changes in thermal and hydrology regimes lead to the redistribution of tree species and tree vigor and growth changes [1, 2]. Thus, conifers in the boreal zone have experienced large-scale decline and mortality caused by the combined influence of wildfires, droughts, and pathogen attacks. Conifer mortality has been observed in North America, where a synergy of droughts, fires, and bark-beethe attacks has caused pine stand mortality over vast areas [3, 4, 5]. Large-scale decline and mortality of spruce (_Pica abies_ L., _P.  
_obovata_ L.) in Western and Eastern Europe and in the European part of Russia is attributed to low precipitation and root-zone humidity in combination with bark-beetle attacks [6; 7; 8]. In the Mediterranean zone, the future of the endemic pines is strongly dependent on the combined effect of drought and fire [9]. Alongside conifers, softwood and hardwood species have also experienced negative consequences of climate warming in the boreal zone [10; 11].  
In Siberia, precipitation-sensitive Siberian pine (_Pinus sibirica_ Du Tour), fir (_Abies sibirica_ [PERSON]), and spruce (_Picea obovata_) have experienced growth decline and mortality within areas of low precipitation (i.e., taiga forests in the lowlands) [12; 13]. By contrast, rising air temperatures drive the uphill migration of those species to areas of sufficient moisture supply, e.g., into the mountain tundra [14].  
Scots pine (_Pinus sylvestris_ L.) can survive in habitats with limited water supply, including semi-desert areas. In addition, this pyrophytic species has adapted to periodic surface fires. However, recent data have indicated a negative influence of the burning rate on the growth and area of pine stands, especially within the southern range of pine [15; 16; 17; 18]. Similarly, other Siberian pyrophytic and drought-resistant species, e.g., larch (_Larix_ spp.), have experienced thinning and mortality of stands within the southern edge of their habitat in the TransBaikal area [19; 20; 21]. Most of the observed warming-driven negative and positive influences on trees refer to the so-called period of the \"warming restart\", i.e., a pronounced increase in the warming rate since ca. 1998 [22].  
Prognostic models suggest that the most pronounced changes in tree vigor and range should occur within the transitions (ecotones) between forest and non-forest communities [1]. This study focuses on Scots pine tree growth and pine forest burning during the \"warming restart\" in the 21 st century. For our study, we selected relict pine stands at the southern edge of the _Pinus sylvestris_ range in Siberia. We analyzed the dependence of the radial growth index (GI) of trees on climate variables and the influence of wildfires on pine forests.  
Checked hypothesis:  
1. Warming-driven air temperature increase stimulates the growth of _Pinus sylvestris_ in conditions of sufficient moisture supply;
2. Warming-driven increase in burning rate is a threat to the _Pinus sylvestris_ habitat within its southern range in Siberia.  
We are seeking answers to the following questions:  
1. How do changing hydrothermal regimes influence the growth index of pine trees?
2. How does the changing burning rate influence pine stands and pine regeneration?