The study of climate resilient urban environment formation background in the conditions of a mountain coast and monsoon climate: the case of Vladivostok.

Kazantsev Pavel Anatolievitch PhD in Architecture Professor; Department of Architecture and Design; Far Eastern Federal University 690922, Russia, Primorsky Krai, Vladivostok, Ajax str., 10, office C921 pal-antvlad@yandex.ru Other publications by this author     Berezina Anastasiya Aleksandrovna Master's Degree; Department of Architecture and Design; Far Eastern Federal University 690922, Russia, Primorsky Krai, Vladivostok, Ajax str., 10, office 921 bela_345@mail.ru Bolehivskaya Alena Yaroslavovna Master's Degree; Department of Architecture and Design; Far Eastern Federal University 690922, Russia, Primorsky Krai, Vladivostok, Ajax str., 10, office 921 alena-yarsk@yandex.ru Burdina Dar'ya Pavlovna Assistant; Department of Architecture and Design; Far Eastern Federal University 690922, Russia, Primorsky Krai, Vladivostok, Ajax str., 10, office C921 dariav93@yandex.ru Other publications by this author     Van-Ho-Bin Egor Aleksandrovich Senior Lecturer; Department of Architecture and Design; Far Eastern Federal University 690922, Russia, Primorsky Krai, Vladivostok, Ajax str., 10, office 921 van-kho-bin.ea@dvfu.ru

Marus Yana Viktorovna Assistant; Department of Architecture and Design; Far Eastern Federal University 690922, Russia, Primorsky Krai, Vladivostok, Ajax str., 10, office C921 vl_yana@mail.ru Other publications by this author

Introduction

The formation of greater Vladivostok is inevitably accompanied by the development of natural landscapes, with the transformation of the quality of their interaction with environmental factors. The loss of forest cover, high-rise buildings and the layout of the territory, the expansion of the road network and industrial zones, the engineering arrangement of the coastline radically change the initial wind, insolation and hydrological regime. The scale of the planned development of the coast of the Amur and Ussuri Bays, the adjacent territory, proposed by the developed master plan of Vladivostok and other urban planning documents (including plans for the development of the territory of Sputnik, Artyom and BUT Bolshoy Kamen) allow us to talk about a fundamental change in the landscapes of the South Primorsky agglomeration by 2030. Under these conditions, it is important to understand the changing climate-regulating properties of newly formed and preserved landscapes and their impact on the comfort of the urban environment, especially in connection with the observed climate dynamics in the region of the south of the Far East.

In modern urban planning practice, the resilience of cities to climatic changes, such as rising temperatures, rising sea levels, increasing intensity and duration of storm precipitation, recurring storm winds, is considered as a leading factor in maintaining the attractiveness of the urban environment for humans and ensuring high dynamics of territorial development. It is noted that without adaptation measures, these changes will lead to flooding on land and coast, damage from storms, increased stress on managed and natural systems and negative consequences for public health, such as overheating during an increase in summer temperatures. Along with social and economic sustainability, the importance of ensuring the spatial resilience of cities to climate change is emphasized ^[1,2]. Urban planning documentation on the formation of a climate-resilient environment is being developed or is in operation in more than 100 cities around the world, including such large coastal megacities as New York, Boston, Seattle, Melbourne, Copenhagen, Rotterdam. In this study, the cities of the Pacific coast with a monsoon or close to it climate and difficult terrain are identified – Hong Kong, Shenzhen, Xiamen, Busan, Wellington, Vancouver. The landscape and climatic conditions of the cities of this group allow us to consider them as possible prototypes for the development of a regional model of a climate-resistant urban environment.

The object of this study is the urban environment in combination of natural and anthropogenic landscapes in conditions of climate change. The subject of the study is the influence of the characteristics of anthropogenic and natural landscapes of the urban area on the stability of the urban environment to the dynamics of climate change in coastal mountainous areas with a temperate monsoon climate. The boundaries of the study are the territory of the main urban development spot of Vladivostok, located on the Muravyov–Amursky Peninsula south of the Sedanka River. The choice of this territory is due to the wide variety of anthropogenic and preserved natural landscapes typical of coastal towns of Primorye. The purpose of the study is to identify the specifics of the formation and determine the main parameters of an architectural and spatial model of a climate–resistant urban environment for the conditions of the southern coast of the Far East.

The main trends in changing climatic conditions in the south of the Far East

Global warming caused by human activity and related climate changes are obvious, and the scientific community is practically uncontested. In general, a common understanding of the consequences of global warming for the south of the Far Eastern region has been achieved in terms of the dynamics of the main climatic indicators. First of all, it is noted that the monsoon circulation of air masses will remain in the south of the region. Stable monsoon circulation has been observed here for several hundred thousand years, with variable intensification of the effects of continental or oceanic air masses, respectively, in cold and warm climatic epochs ^[3]. Despite the increase in temperatures, this gives reason to consider the regulation of the wind and insolation regime of the winter period as necessary components of the formation of an urban environment resistant to climatic changes. The prevailing north-north-west and south-east directions of continental and offshore winds in the Vladivostok area will also remain.

The dynamics of the climate will affect the increase in the duration of overheating conditions, the regime of atmospheric precipitation and the increase in the level of the Sea of Japan. If the trend towards climate warming continues, an increase in the average annual air temperature by 2.5 - 3.0 °C should be expected ^{[4, 5]}. In combination with the high humidity characteristic of the seashore and summer insolation warming, a significant increase in the duration of uncomfortable hot stuffy weather should be expected ^[6]. To preserve the comfort of the urban environment, this factor becomes equivalent to the previously prevailing uncomfortable combination of the winter monsoon and low temperatures ^[7]. In the last decade, in comparison with the previous one, an increase in the amount of summer precipitation has been recorded in the south of the Far East ^[8]. The generalized forecast of precipitation dynamics shows a possible doubling of their amount by the end of the century, with a twofold increase in the intensity of rainfall ^[9]. Given the steep, shallow slopes of the hills characteristic of the city, an increase in the number of cases of flooding of urban lowlands should be expected. In their low-lying estuaries, the repeated effects of storm precipitation will overlap with the flooding of the territory due to a gradual rise in the level of the world ocean to 2 m. by the end of the century, predicted due to the acceleration of melting of the Antarctic ice shelves (extreme forecasts up to 4-5 m) ^[10,11].

The state of the problem of accounting for the dynamics of climate change in the formation of the urban environment in areas with similar landscape and climatic conditions

In mountainous areas of the Pacific coast with a monsoon or close to it climate, the bioclimatic comfort of the urban environment primarily determines the orographic pattern of the territory and the degree of its anthropogenic transformation. Additional factors of changes in insolation warming, hydrological and humidity conditions, and aeration qualities of the territory are the properties of the surfaces forming urban landscapes and their vegetation cover. When developing models of a climatically stable urban environment, the selected characteristics of urban landscapes are evaluated according to the degree of their influence on environmental factors, in order to identify the territorial distribution of climate change risks.

In the reviewed cities of the Pacific coast (Hong Kong, Shenzhen, Xiamen, Busan, Wellington, Vancouver), the assessment was carried out in the following main areas: - identification of the boundaries of the preserved natural forest cover, usually tied to peaks, watersheds and upper elevations of mountain slopes, as a factor influencing the reduction of overheating and regulation of storm runoff (Hong Kong, Shenzhen)^[12,13]; - identification of territories available for expanding the canopy of urban forests in order to increase the possibilities of natural cooling (Vancouver, Wellington) ^[14,15]; - identification of wind corridors formed by natural terrain and subsequent assessment of changes in their permeability to summer wind during the formation of buildings of different storeys as a factor affecting the aeration of the territory (Hong Kong, Shenzhen) ^[16,17,22]; - assessment of the unevenness of precipitation in mountainous areas at a distance from the coast in order to identification of areas with a high risk of heavy precipitation (Busan, Xiamen) ^[18,19]; - analysis of the state of the river network, identification of a network of surface watercourses and areas flooded by storm precipitation (Hong Kong, Xiamen, Wellington) ^[12,13,15]; - identification of low-lying areas of the urban coastline prone to flooding in conditions of rising sea levels and storm surge (Hong Kong, Shenzhen, Busan, Vancouver, Wellington) ^[20,21,22]; - identification of the territorial distribution of density gradations of anthropogenic landscapes as a factor influencing overheating and redistribution of storm runoff (Hong Kong, Shenzhen, Busan, Xiamen) ^[22,23].

The Xiamen Climate Adaptation Plan was developed as a basic model for the introduction of sponge city technology in China, therefore, it focused on assessing the resilience of the urban area to floods with an average annual and storm precipitation distribution. Storm precipitation management is also seen as a key element of climate adaptation in Vancouver and Wellington. Due to the predominance of moderately comfortable winter weather for these cities, the problem of wind protection in winter was not considered, and the assessment of the aeration qualities of the building was focused on the summer wind regime. When assessing the influence of the topography of an urban area on climatic risks, the temperature gradient was also taken into account in connection with changes in the height of urban hills ^[22]. Due to the lower elevation of the Vladivostok relief, the high-altitude temperature gradient on its territory is not so obvious ^[24]. The identification and conservation of forests covering the peaks and watersheds of urban hills of coastal megacities in China dates back to the traditional practice of Feng Shui, formed in the conditions of anthropogenic development of mountain monsoon landscapes ^[25]. The dynamics of the formation of new forests in the city can be quite significant, for example, by 2050 in Vancouver it is planned to increase the canopy of urban forests by 30% ^[14]. The Wellington climate adaptation program, along with an increase in vegetation cover and engineering regulation of the coast, prescribes a "retreat" from vulnerable urban areas ^[15]. Based on the results of the assessment of climate risks in each of the cities under consideration, techniques for architectural and spatial adaptation of the urban environment to increased precipitation, sea level rise and air temperature increase were developed (Fig. 1).

Methodology for assessing the bioclimatic comfort of the territory in predicting the impact of climate change on the urban environment

The methodology for identifying climate risk zones in this study is based on an assessment of changes in the direction and intensity of the action of vector climatic factors – wind and solar radiation – by low-mountain terrain and urban development ^[26]. Due to the sharp climatic contrast of the sides of the horizon in mountainous coastal areas with a temperate monsoon climate, it is the change in the characteristics of the wind and insolation regime that significantly corrects the remaining meteorological parameters - precipitation mode, air temperature and humidity, degree of humidification and temperature of the earth's surface. As a result, thermal contrasts in relatively small areas between shaded and insolated slopes, blown peaks and wind-sheltered valleys can be equivalent to thermal contrasts between temperate and polar climatic zones ^[7,25]. Therefore, data on the territorial distribution of wind and insolation regime characteristics allow us to assess possible risks associated with climate dynamics and identify resources for their correction. The assessment of the flooding of the coastal marine area in this study is based on the predicted dynamics of the rise in the water level of the world ocean. The coast of the Ussuri Bay, windward of the southeastern monsoon, faces the sea with a high steep coast, and for such a landscape the impact of storm surge is relatively small.

Fig.1. Techniques of architectural and spatial adaptation of the urban environment to climate change (graphics Bolekhivskaya A.Ya., Kazantsev P.A.)

Fig. 1. Urban environment architectural and spatial climate change adaptation practices (graphics by Bolekhivskaya A.Ya., Kazantsev P.A.)

The initial materials for the analysis were maps of the zoning of the territory of Vladivostok according to the annual course of the wind and insolation regime, made by the authors of the article as part of a study of the bioclimatic comfort of the southern part of the Muravyov-Amursky peninsula ^[27,28], materials of the current General Plan of the city ^[29] and the master plan of Vladivostok being developed ^[30]. The article presents a final map of the bioclimatic comfort of Vladivostok landscapes, summarizing the results of assessing the interaction of vector climatic factors and the initial topography of the city, without taking into account its anthropogenic changes (Fig.2.a.). Modeling of the microclimate of the territory of Vladivostok was performed for the prevailing monsoon winds of the north-west and south-east directions, taking into account the dynamics of the insolation of the relief in winter and summer, on the characteristic days of the most frosty and warmest months - January 20 and July 20. The scheme of the Vladivostok master plan shows the main directions of the territorial development of the city until 2030, identifying new areas of the emerging anthropogenic landscapes (Fig.2.b.)

Fig.2. A map of the assessment of the bioclimatic comfort of the territory of Vladivostok (A); a diagram of the main development territories according to the master plan of Vladivostok (B) (here and further graphics Kazantsev P.A., Wang-Ho-Bin E.A., Marus Ya.V.)

Fig. 2. Vladivostok city area bioclimatic comfort assessment map (A); key development areas diagram (according to Vladivostok city master plan) (B) (hereinafter graphics by Kazantsev P.A., Van-Kho-Bin E.A., Marus Y.V.)

The influence of the orographic structure of the southern part of the Muravyov-Amursky peninsula on the boundaries of climate risk zones

To identify the general picture of the distribution of climate risk zones in the territory of Vladivostok, at the initial stage of the study, the assessment of the influence of the orographic structure of the southern part of the Muravyov-Amursky Peninsula on the formation of bioclimatic comfort was carried out without taking into account the anthropogenic component of urban landscapes. The mapping of the territory was carried out for the initial relief, based on an earlier assessment of the annual course of the wind and insolation regime of the Muravyov-Amur Peninsula south of the Sedanka River as part of the development of the spatial planning regulations of Vladivostok (2016 and 2023), and an assessment of the bioclimatic comfort of the main urban development spot of Vladivostok and its island territories (2006). ^[26].

The differentiation of the city's territory was carried out according to the effects of the following climatic factors: – Wind exposure in winter was assessed as an additional cooling factor at low temperatures (the duration of the period observed today with wind speeds above 4 m/s at temperatures below -5 ° C in 70-90 days suggests the need to take into account the uncomfortable cooling effects of the northern monsoon in in the near future) (Fig. 3). Additionally, zones favorable for the use of insolation resources in the cold season were allocated in the urban area (Fig.4). - Summer insolation overheating of urban landscapes during the movement of the sun in the southern, southwestern and western sectors of the sky, superimposed on calm zones in the southeastern The wind direction was assessed as the dominant factor in the future due to the observed temperature dynamics (Fig. 5). - Storm wind impact in the summer, despite the short duration of the impact, was assessed as a particularly unfavorable factor associated with a combination of an increase in precipitation intensity with a simultaneous increase in the wind pressure of the summer monsoon wind (a combination of strong monsoon winds and rains with a change in wind speed, the relief leads to uneven precipitation and the formation of storm drains on the territory of the city) (Fig. 6). When assessing the threat of flooding of low-lying territories, the landscapes of the seashore with marks below 2 and 5 meters, and the mouths of urban ravines and valleys flooded by rain storm drains were highlighted.

Fig.3. Assessment of the distribution of winter insolation (A) and wind (B) discomfort zones

Fig. 3. Winter insolation (A) and wind (B) discomfort areas distribution assessment

Fig.4. A comprehensive assessment of winter discomfort on the territory of the main urban development spot of the city.

Fig. 4. Comprehensive assessment of winter discomfort within the city’s main urban planning area.

Fig.5. Territories with summer insolation discomfort and calm zones (southern, southwestern and western slopes and plains, and landforms closed from the summer monsoon wind)

Fig.5. Territories with summer insolation discomfort and calm zones (southern, southwestern and western slopes and plains, and landforms protected from the summer monsoon wind)

Fig.6. Areas affected by stormy weather, including a combination of high south-easterly wind speed with precipitation, flooding of lowlands by storm precipitation, as well as a flooding zone when the world ocean level rises by 2 and 5 m.

Fig.6. Territories exposed to stormy weather, including a combination of high speed south-east winds with precipitation, flooding of lowlands with storm precipitation, as well as a flooding zone when the world sea level rises by 2 and 5 m.

A subsequent comparison of the boundaries of the territories of the prospective development of the city until 2030 ^[30], with the revealed distribution of climate risk zones, showed that:- The main array of territories for the prospective development of residential buildings falls on the summer storm zone from the Ussuri Bay. At the same time, these territories are well ventilated in summer overheating, due to the shallow depth and significant steepness of the slopes, they quickly dump storm precipitation into the marine area, are closed from winter winds and have good insolation resources in the cold season; - The territory with summer insolation discomfort has planned public, business and residential development along the shore of the Amur Bay and at the mouth of the valleys of the First and Second Rivers, in Kuperovaya Pad. Directly in the coastal zone, the insolation overheating of this territory is compensated by ventilation, but when moving from the sea along river valleys, the development extends to summer calm zones; - These sites located along the coast are open to winter monsoon winds, and at the mouths of the valleys are in the flood zone during storm precipitation and flooding of urban rivers. And due to the flatter terrain and a larger catchment area, the mouths of the valleys facing the Amur Bay may be subject to longer flooding during the rainy season.; - The flooding zone, taking into account the rise in the level of the world ocean, except for the mouths of river valleys, where the depth of seawater penetration can be quite significant, threatens only a narrow strip of port facilities and embankments, but this is the most valuable resource for the development of the city.

Dynamics of forest cover and its possible use as a means of correcting climate change

The role of vegetation cover in mountainous areas with a monsoon climate in the formation of thermal comfort and stable hydrological regime was well known in East Asia thousands of years ago and recorded in the canons of Feng Shui. The forest area on the peaks and watersheds protects from wind, reduces overheating, regulates the collection and distribution of storm precipitation, and maintains the water content of the river network in the dry season ^[24]. Therefore, a comparison of the forest cover of secondary forests preserved on urban hills in the early years of the construction of the "Greater Vladivostok" with the forest cover of the city in 2013 (following the completion of the construction program of the APEC Forum 2012), and with its possible change by 2030 (following the implementation of the master plan of Vladivostok 2023) can give more a complete understanding of the dynamics of the climatic stability of urban landscapes.

The assessment of forest cover in the early years of the construction of the Greater Vladivostok was carried out on the basis of aerial photography data from 1965 ^[31]. To a large extent, the forest cover was preserved in areas exposed to storm effects and, therefore, continued to play an important role in reducing the speed of South wind, regulated precipitation, and ensured a decrease in the intensity of storm floods. First of all, these were the forests that covered the peaks, watersheds and slopes of the Rich Mane ridge, overlooking the Ussuri Bay. At the same time, a significant part of the territory of the valleys and slopes of the southern, southwestern and western orientations of the southern part of the Muravyov-Amursky Peninsula was already deprived of forest cover and built up by this time, therefore, the forest cover in the territory under consideration by 1965 could no longer have a noticeable effect on reducing insolation overheating (Fig.7.).

By 2013, the forest cover of the territory had been significantly changed by the massive sectional development of the 1970s and 80s, and the construction program of the APEC Forum 2010-12. By this time, the forest cover was almost completely lost in areas with insolation overheating and calm zones, and it can be stated that in the city any noticeable role of natural forests in mitigating summer thermal discomfort was lost. But there were still forests – regulators of atmospheric precipitation and storm runoff on the peaks and watersheds in the upper reaches of the urban rivers of the Explanation, the First and Second rivers, in the windward part of the Muravyov-Amursky Peninsula (Fig.8.).

Fig.7. Comparison of the boundaries of the forest cover with territories with maximum insolation warming and stagnation of air in hot humid weather, and with territories of intense exposure to stormy weather as of 1965.

Fig. 7. Forest cover boundaries compared to areas with maximum insolation heating and air stagnation in hot, humid weather, and with areas of intense exposure to stormy weather as of 1965.

Figure 8. Comparison of overheating and storm discomfort zones with the boundaries of forest cover as of 2013

Fig. 8. Overheating and storm discomfort areas compared to the boundaries of forest cover as of 2013.

Forest cover by 2030 was estimated in accordance with the boundaries of the territories of prospective development of Vladivostok by 2030. By this time, forests in the boundary of the catchment basin of the river Explanations will completely disappear, there will be little forest cover in the upper reaches of the First and Second rivers, after the construction of the Ussuriysky district, the forest cover of the windward slopes facing the Ussuriysky Bay will be significantly reduced. The protective effect of storm regulation of forests for the main urban development area of Vladivostok will be almost completely lost. When assessing thermal discomfort, it is also clear that the same river valleys, which are characterized by stagnation of air in hot, humid weather, completely lose forest cover, and its compensatory effect on the temperature and humidity regime of the territories under consideration (Fig.9.). Formed over thousands of years and possessing a significant margin of stability and more diverse options In a short period of time, natural landscapes have been replaced by anthropogenic ones, requiring special study of spatial solutions for their adaptation to the observed climate dynamics.

Fig.9. Comparison of overheating and storm discomfort zones with the boundaries of forest cover as of 2030

Fig. 9. Hot areas and storm discomfort areas compared to forest cover boundaries as of 2030.

The influence of anthropogenic landscapes on the dynamics of climate change

Urban development of small-scale relief over time radically changes its spatial characteristics and forms a new topography of Vladivostok (Fig. 10). Panoramas of the development of the central part of the city in 1-3 floors at the end of the XIX century and a panorama of the central part of the city in the early 80s of the XX century show that with the bulk of the development up to 5 floors with the inclusion of separate 9-12 storey point buildings, the complexly dissected low-altitude relief of the peninsula retains its dominant character over urban development. But since the early 80s, during the transition to the mass construction of hills with sectional houses of 9 floors and, as can be seen on the panorama of the central part of the city in 2024, especially with the appearance of 20-25-storey high–rise buildings in the valleys and watersheds of the hills, the development subordinates the original relief of the Golden Horn Bay amphitheater. The spatial characteristics of the "watersheds" of linear sectional and "peaks" of high-rise point buildings, the slopes and retaining walls formed during the placement of buildings are comparable to the spatial characteristics of the forms of the original natural relief. The topography of multi-storey urban development is becoming an active factor in changing the wind, insolation and hydrological regime of anthropogenic landscapes of Vladivostok in its modern and planned borders.

To assess the dynamics of the microclimate in the process of urban development, a site was selected located on the Shkota Peninsula, within the boundaries of Verkhneportovaya and Lieutenant Schmidt streets. The ridge of the peninsula's shallow relief stretched from north to south, surrounded on three sides by the sea and open to monsoon winds, can be considered a reference territory when analyzing the landscape and climatic conditions of Vladivostok. Based on the mapping of the city's territory in the second half of the XIX century ^[33], the reconstruction of the microclimatic characteristics of the site in the pre-Urban period was carried out, and the subsequent assessment of their current state. As shown by computer modeling, the spatial characteristics of the initial shallow relief, smoothed by weathering and covered with forest, contributed to the uniform redistribution of wind and insolation conditions, with the formation of microclimatic zones significant in territory and clearly linked to the exposure of slopes (Fig.11). On the contrary, the microclimate of modern anthropogenic landscapes, including quarterly and lowercase 4 - 7 storey buildings, and a group of dotted 18-storey buildings has a mosaic character (Fig.12). The "spots" characteristic of the northern slopes, blown by the continental monsoon and experiencing a shortage of insolation in winter, extend to the southern slopes, previously closed from winter discomfort. Winter comfort zones appear on the northern slopes near the southern facades of linear buildings, gale-force winds of the south-east direction and oblique rains become characteristic of previously sheltered areas, etc. There is fragmentation and reduction of the area of microclimatic zones. In general, the climatic contrast within previously homogeneous zones increases, their mosaicism increases, and the contrast of the annual course of the wind and insolation regime between heterogeneous terrain areas is leveled. This trend reflects the change in the distribution boundaries and the area of the habitats of plant systems (Fig. 13).

Fig.10. Dynamics of changes in spatial characteristics of urban landscapes in the process of their anthropogenic development: Natural landscapes of the southern coast of O. Russian, Vladivostok, and panoramas of the northern shore of the Golden Horn Bay (the central part of the city) at the turn of the XIX–XX centuries ^[32], at the end of the XX century and in 2024 (graphics by Pavel Kazantsev)

Fig. 10. Urban landscapes spatial characteristics dynamics in the process of their anthropogenic development: Natural landscapes of the southern coast of the island. Russky, Vladivostok, and panoramas of the northern shore of the Golden Horn Bay (the central part of the city) at the turn of the 19th–20th centuries. ^[32], at the end of the 20th century and in 2024 (graphics by Pavel Kazantsev)

11. Microclimate of natural landscapes (Fig.11-13 graphics Berezina AA)

Fig. 11. Natural landscapes microclimate (Fig. 11 -13 graphics by Berezina A.A.)

Fig.12. Microclimate of anthropogenic landscapes

Fig. 12. Anthropogenic landscapes microclimate

Fig.13. Changes in the distribution of habitats of plant systems

Fig. 13. Plant systems distribution changes

The change in the area and boundaries of microclimatic zones will depend on the types of development of the initial relief. Typical for the initial stage of urban development of the Muravyov-Amursky Peninsula landscapes, low and medium-rise buildings are located in the high-rise zone of secondary deciduous forests of the peninsula and mainly complement the natural topography of urban hills, multi-storey buildings of 9 or more floors transform the climate-regulating properties of low-mountain terrain (Fig.14).

Fig.14. Panorama of the amphitheater of Diomede Bay, which includes the main types of urban development: 1-3, 5-7, 9 floors and high-rise buildings of 25-30 floors. In the background, the natural landscapes of Russian Island are visible. (photo and graphics by P.A. Kazantsev)

Fig. 14. Panorama of the Diomede Bay amphitheater, including the main types of urban development: 1-3, 5-7, 9 floors and high-rise buildings of 25-30 floors. In the background you can see the natural landscapes of Russky Island. (photo and graphics by Kazantsev P.A.)

Low-rise buildings of 1-3 floors can be almost completely hidden by secondary woodland, quarterly high-density and low-rise buildings up to 5-7 floors go to the border of the formation of the canopy of secondary deciduous forest. By forming a common "canopy" of roofs and tree crowns, buildings of these types preserve the dynamics of the annual course of the wind regime characteristic of natural landscapes. Low-rise buildings of 1-3 floors also have almost no effect on the annual course of the insolation regime characteristic of the natural relief. Quarterly high-density and low-rise buildings up to 5 floors form mosaic shadow zones in the adjacent territories in winter, in summer in combination with landscaping - solid shadow zones.

Buildings of 9 or more floors, in terms of their size and height, are comparable to the spatial characteristics of a small-scale relief, and are already capable of radically transforming its microclimate. Sectional buildings of 9 floors along the horizontal of the hills, characteristic of the 80s, formed wind corridors and zones of continuous winter shading on slopes and flat watersheds. Buildings of 25-30 floors typical for modern buildings, when placed in valleys previously sheltered from the wind, form a wind-catching effect, radically changing the winter and summer wind microclimate. The same buildings on the tops of the hills will throw the wind down. Stained glass windows of high-rise plates on the northern slopes create zones of comfortable winter intermia, on the southern and western borders there is an overlap of fields of direct and reflected solar radiation of the summer overheating zone.

The spots of multi-storey buildings form new spatial characteristics of the orographic framework, in terms of changing the structural pattern of watersheds and peaks, tallwegs, valleys and basins (Fig.15). The valleys are filled with high-rise buildings, "lifting" the bottom of the valleys to the marks of the watersheds that sheltered them (residential areas of Green Corner and Snowfall, buildings of Pigeon Fall). In pursuit of views, high-rise buildings are placed on the preserved voids of watersheds and peaks, increasing the high-rise contrast with the low-rise buildings of medium height (Tigrovaya Hills, Eagle's Nest, watersheds of the amphitheater of Diomede Bay). At the same time, the new anthropogenic topography, formed by rows of point buildings, as opposed to a merged quarterly one, forms landscapes permeable to wind, insolation and precipitation. But their intensity at the level of the lower tier of the building varies many times – from complete disappearance to an increase in the intensity of the impact by 2-3 times.

Fig.15. The new topography of the city: A. Zones of multi-storey buildings of 9-30 floors according to the current general plan of Vladivostok and proposed for development until 2030 according to the master plan of the city; B. Changing the orographic pattern of the city territory with multi-storey buildings (graphics Kazantsev P.A., Burdina D.P.)

Fig. 15. New topography of the city: A. Multi-storey development zones of 9-30 floors according to the current master plan of Vladivostok and proposed for development until 2030 according to the city master plan; B. Change in the orographic pattern of the city territory by multi-story buildings (graphics by Kazantsev P.A., Burdina D.P.)

Taking into account the geometric parameters of the planned and implemented high–rise buildings - a group of towers or plates of 20-30 floors (60-90 meters at the height of the main urban watersheds of 100-150 meters), the influence of such residential areas on the microclimate of neighboring urban areas will also be significant, and may be expressed in the imposition of vortex zones of secondary wind flows with a change in the speed and direction of the initial monsoon wind, changes in the direction and intensity of precipitation. This will be most typical for areas of multi-storey buildings on slopes and watersheds of the eastern coast exposed to summer storm effects (residential areas of Patroclus, Ussuriysky). The high-rise development of the coastline of the Amur Bay at the mouths of the valleys of the First and Second rivers, at the mouth of the valley of the river Explanation, will block their aeration corridors, turn the valleys into a kind of basins, exacerbating air stagnation in hot calm weather.

Thus, multi-storey buildings form a new spatial framework of the city, which becomes an integral part of the original orographic framework, and radically changes the microclimate of the original landscapes not only within its borders, but also in the surrounding area. Considering that in the current development and ongoing projects, the spatial characteristics of multi-storey buildings can no longer be used to correct negative climate dynamics, the zones of existing and projected multi-storey buildings should be classified as zones of increased climatic risk (Fig.16). According to the authors, the restoration of the climatic stability of new anthropogenic landscapes is possible only when they are formed as a single architectural and landscape system of buildings, vertical planning and green systems (the concept of a biotope city) ^[33].

Fig.16. The location of high-rise buildings relative to the zones of winter and summer wind discomfort (graph Kazantsev P.A.)

Fig. 16. Location of high-rise buildings relative to zones of winter and summer wind discomfort (graphics by Kazantsev P.A.)

An architectural and spatial model of the formation of a climate-resistant urban environment

Considering the coastal city in the conditions of the region in all the diversity of its preserved natural and formed anthropogenic landscapes interacting with climate factors, we can propose the following architectural and spatial model for the formation of an urban environment resistant to climate change (Fig. 17). The model is based on the initial orographic drawing of the territory, which is the basis of its natural framework, including: - peaks and watersheds (the main landforms affecting the redistribution of wind regime characteristics and precipitation regime), tallwegs and river valleys (the main directions of storm runoff formation), low-lying coast with adjacent shoals (the zone of flooding and storm effects in conditions of rising sea levels). Most of the territory, including slopes and flat surfaces, with various characteristics of exposure, porosity and reflectivity (albedo) can be attributed to the fabric forming the urban environment.

In modern conditions of continuous urban development of Muravyov-Amursky Peninsula, when, with the development of engineering and construction technologies, the initial shallow relief ceased to be an obstacle to the urban transformation of natural landscapes, the degree of their anthropogenic change can be estimated without reference to the original orographic pattern. Taking into account the leading role of the permeability properties of the surfaces forming urban spaces in changing their humidity and temperature conditions, their density as a ratio of porous and moisture–impermeable surfaces can be used as the basis for assessing the degree of anthropogenic change in landscapes, This approach is similar to the accepted method of forming a "porous" urban environment (WSUD - Water Sensitive Urban Design)^[34]. In this study, it is proposed to identify zones with high, medium and low levels of anthropogenic change for the structural elements forming the natural framework and fabric of the urban area according to the criterion of "density" of development and engineering improvement. Due to their spatial characteristics, multi-storey building zones in the conditions of a complexly dissected low-altitude relief peculiar to the region can be allocated to a separate group of anthropogenic landscapes, as a factor actively changing the initial orographic pattern of the territory (Fig.17.).

In regions with high wind speeds in combination with intense rainfall, the tiered structure of urban development and its altitude play an important role in the formation of bioclimatic comfort ^[35]. This fact confirms the well-known regularity of the distribution of properties of changes in wind, insolation, and precipitation modes between the tiers of the forest. To a large extent, the tiered structure of urban development coincides with the tiered structure of temperate forests (Fig.18.) Taking into account the redistribution of climate-regulating functions of buildings vertically and taking the tiered structure of temperate forests as an analogue of the vertical structure of each of the selected zones, we can propose the following differentiation of the urban environment vertically. The outer level is formed by multi–storey buildings, which include two main types of buildings of 9-16 floors, and 20-30 floors. The outdoor level interacts with wind currents passing over the urban landscape, and due to the "wind-catching" effect is the leading factor in the formation of a map of the aeration field and precipitation zones of varying intensity. The level of cover (canopy) is the level of roofs of medium–rise buildings corresponding to the crowns of deciduous trees of secondary forests and landscaping of the urban area. With successive landscaping of the territory over time, a plane is formed as a continuous following the natural topography of the territory, bringing the zone of wind exposure and insolation discomfort above the level of pedestrian traffic. The level of undergrowth corresponding to the level of formation of active facades of the lower floors of buildings and the level of pedestrian traffic acts as an additional layer of redistribution of climatic discomfort due to the placement of small architectural forms, shrubs, green screens and low trees. The litter level corresponds to the vertical layout of the territory, whose spatial characteristics and permeability of the forming surfaces affect the final redistribution of insolation heating and water flows.

The proposed tiered structure of the urban environment model during its formation will allow distributing the functions of regulating the dynamics of climate change vertically and neutralizing the adverse effects of the spatial characteristics of the existing and projected multi-storey buildings.

Fig.17. An architectural and spatial model of the formation of an urban environment resistant to climatic changes for the conditions of the southern coast of the Far East (graphics by Wang-Ho-Bin E.A., Marus Ya.V.)

Fig. 17. Climate resistant urban environment formation architectural and spatial model for the conditions of the southern coast of the Far East (graphics by Van-Kho-Bin E.A., Marus Y.V.)

Fig.18. The tiered structure of urban development corresponding to the tiers of temperate forests (graphics Kazantsev P.A., Smelovskaya A.M.)

Fig. 18. Urban development layered structure corresponding to the layers of temperate zone forests (graphics by Kazantsev P.A., Smelovskaya A.M.)

Conclusion

The results of the study showed that:

The main climatic risk zones in the considered territory of Vladivostok will be: - the slopes of the eastern coast of the Muravyov-Amursky peninsula exposed to the southeastern monsoon, as well as peaks and watersheds throughout the peninsula (wind exposure combined with heavy precipitation); - westward-oriented river valleys and built-up tallwegs (flooding by storm precipitation and excessive insolation heating in hot, stuffy weather); - estuaries of valleys, lowlands and alluvial territories of the western coast of the peninsula, port facilities and embankments of urban bays (flooding as a result of a gradual increase in the level of the world ocean). Due to the completion of its cutting south-west of the conventional line running along the Sedanka-Patroclus highway, by 2030 the forest cover will no longer be able to compensate for the risks associated with storm precipitation and overheating within the main development area of Vladivostok.

Since about the turn of the 70s and 80s, and especially since 2013, multi-storey buildings have been actively changing the initial orographic pattern of the urban area, forming a mosaic map of the wind, insolation field and precipitation distribution, with a contrasting change in the intensity of the action of these factors. The new topography of the city increases the area of climate risk zones not only within the newly formed territories of multi-storey buildings. When high-rise buildings are located at the mouths of valleys or on the tops and watersheds of hills, their influence can spread over large areas.

The proposed architectural and spatial model of the formation of an urban environment resistant to climatic changes considers it as a set of preserved natural and formed anthropogenic landscapes. According to the criterion of "density" of building and engineering improvement, zones with high, medium and low levels of anthropogenic change are identified for the structural elements forming the orographic framework and fabric of urban landscapes. The layered structure of the model will make it possible to distribute the functions of regulating the dynamics of climate change vertically and highlight the leading role of restoring such tiers of the urban environment as "undergrowth" and "cover", if it is impossible to change the spatial characteristics of the existing and projected multi-storey buildings.