Modern Climate Warming Research Articles

CLIMATIC AND PHENOLOGICAL INDICATORS OF MODERN WARMING IN THE TERRITORY OF THE UDMURT REPUBLIC (A CASE STUDY OF IZHEVSK)

The article presents the results of the assessment of the dynamics of climatic and phenological indicators from the point of view of the processes of modern climate warming in the territory of Izhevsk (Udmurt Republic). It is established that the pronounced warming trend has been manifested since 1988, taking an unambiguous character since the 2000s. Relative to the base period of 1961-1990, the average annual air temperature in Izhevsk increased from 2.5 °C to 3.3 °C for the climatic period of 1991-2020. The main increase in temperatures can be traced in the cold season, in the winter months, at the beginning of the calendar spring and in the second half of autumn. According to the data presented, the duration of the periods with temperatures of 0, 5 and 10 °C changed upwards by 12, 12 and 6 days, respectively. The average long-term sum of active temperatures above 10 °C for the period 1991-2020 was 2160.9 °C, corresponding to the values of the indicator of the biological efficiency of the climate in the area of the ecological optimum of the functioning of zonal landscapes of the temperate zone. When comparing the current timing of the onset of phenological phenomena in Izhevsk with the period of the 50s-70s of the XX century, their advance by 4-10 days for the spring and summer seasons and a delay of 9-10 days in autumn-winter conditions was established. This affected the change in the length of the seasons with an increase in spring, summer and autumn by 1, 10 and 6 days, respectively, and a shortening of winter by 17 days.

СТОК РЕКИ ЛАНЬ: СОВРЕМЕННОЕ СОСТОЯНИЕ И ПРОГНОЗ

The results of the study of the water regime of the Lan River, a typical small river of the Belarusian Polesye, are presented. The Lan River is represented by three monitoring sites (Lognovichi, Loktyshi and Mokrovo) with drainage areas A = 480 km2, A = 909 km2 and A = 2550 km2, respectively, with different observation periods and the degree of anthropogenic impact. In addition to large-scale reclamation in the river basin, carried out in the middle of the last century, in 1977, a reservoir was built in the river bed for fish farming and agricultural use. Using the method of analogies, the series of observations of annual, maximum, minimum summer-autumn and winter water discharges are reduced to a single calculated period of 68 years from 1948 to 2015. Assessment of the influence of anthropogenic impacts and natural factors on the runoff, the initial time series, the averaging intervals were analyzed: from 1948 to 2015. (the entire observation period length is 68 years); from 1948 to 1977 (29 years period before the commissioning of the Loktyshi reservoir); from 1978 to 2015 (38 years of reservoir operation period); from 1978 to 1987 (10 years period of the reservoir functioning before the beginning of the modern climate warming,); from 1988 to 2015 (27 years period of the reservoir functioning under the current climate warming). Statistical heterogeneity was found as a result of intensive economic activity, which significantly disrupts the natural hydrological regime. It was revealed that for the average annual runoff there is a decrease along the Lognovichi site and an increase along the Loktyshi site; for the maximum runoff, a decrease is observed along all the stations under consideration; for the minimum summer-autumn discharge, an increase is observed along the Loktyshi site; for the minimum winter runoff, an increase is observed along all stations. Based on the hydrological and climatic hypothesis, predictive estimates of the average discharge values for the period of 2050 are given, which are expressed in a certain decrease in it and a shift in the peak of spring flood to earlier dates.

THE STATE OF WATER RESOURCES IN KYRGYZSTAN IN CONDITIONS OF MODERN CLIMATE WARMING

THE STATE OF WATER RESOURCES IN KYRGYZSTAN IN CONDITIONS OF MODERN CLIMATE WARMING

EVALUATION OF THE DURATION OF THE EXTRACTION CYCLE OF LUMP PEAT BY THE CALCULATION METHOD AND ON THE BASIS OF PRODUCTION DATA

The results of the determination of the duration of the cycle of the extraction of lump peat by the calculation method and on the basis of the data obtained in production conditions are presented. The dynamics of drying of lump peat with a diameter of 40 mm under conditions of a radiation-convective regimes is studied. The influence of the intensity of precipitation on the technological and operational indicators of the production of molded products is shown. It was revealed that the coefficient of variation of the number of cycles, one of the main indicators, for a three-year observation period was 33,0 %, which, according to the accepted gradation, is a significant value.
 As a result of a review of published works, it was found that the average long-term climatic data obtained in the 1960s–1970s and used in the calculations of drying of lump peat in a radiation-convective regimes differ significantly
 from the data observed during modern climate warming.

Influence of Modern Climate Warming on the Terms of Basic Phenological Phases in the Population of Spermophilus pygmaeus Pallas, 1778 (Rodentia, Mammalia) on the Territory of the Yergenin Uplands

The results of a comparative analysis of the terms and duration of phenological phases in the population of the little ground squirrel in the central part of the Yergenin Uplands in the years 1926–1932, 1972–1982, and 2000–2015 are presented. It is noted that in the years 1926–1932 all the main phenological life phases of populations of the little ground squirrel took place exclusively during the spring–summer period (March–August). It is proved that in the period 2000–2015, under the influence of modern climate warming, the emergence of the population of the small gopher out of hibernation began to be noted during the winter months (January–February) compared to 1926–1932. The beginning and end of the pregnancy period was recorded between the first ten-day period of February and the third ten-day period of March. Accordingly, preparation for hibernation (fattening) of adult animals began to occur also at an earlier date (March, April) and ended mainly in May. The first appearance of young of the little ground squirrel on the surface and their dispersal began to take place in April–May. The mass hibernation of young ground squirrels was recorded in late June–early July. At the same time, a tendency to increase was noted in comparison with the period 1926–1932 of the total duration of the hibernation period of young animals (July–January or February). A decrease in the intensity of fodder migrations of adult ground squirrels to lowering of the relief was also noted.

Colonization of the young glaciofluvial deposits at the period of the modern climate warming in the North-Chuya glaciation center

We have investigated the early colonization of plants on the highly disturbed glaciofluvlial deposits of the Aktru valley. The modern colonization of the deposits are occurs in their middle part. It was impossible until the modern climate changes because of harsh disturbance regime which was prevented any colonization in this area by regular destruction of both plants and habitats. Now the regime is milder. 100 species from 31 family and 64 genera are participating in colonization now. The most of involved species are high-mountain ones and belong to Poaceae, Asteraceae and Salicaceae families. Most common growth forms of these plants are perennial hers and shrubs. The colonizing Larix trees are exist only as shrub growth form. The formed communities are underdeveloped and may be considered as existing on the pioneer stage of succession. The plant communities development is slow because of harsh disturbance regime thus forming of young forest similar to those in the higher part of the deposits will require a lot of time.

Modern warming, medieval and ancient optimums as the result of orbital changes in the Earth-Moon-Sun system

The root cause of modern climate warming is the influence of gravitational forces on the geospheres of our planet, determined by the orbital configuration of the Earth-Moon-Sun system. The annual changes in the position of the total vector of gravitational forces in space visually reflects the movement of the shadow cone of solar eclipses around the globe. The aim and novelty of the study is to identify the relationship between the number of years with four to five polar eclipses (in periods of pessimums, their number reaches 15-17 years, and in periods of optimums – 2-7 years in a century) and glaciation processes, such as the Fernau fluctuation, Late Antique Little Ice Age, or processes of warming and degradation of glaciers in the Roman and Medieval optimums. The research methods were study, generalization of materials, data synthesis, logical and graphical analysis. The anthropogenic causes of modern warming, which will last until the middle of the 22nd century, are secondary. In the second half of the 22nd century, and throughout the entire 24th century, the advance of the alpine glaciers will be associated with the conditions of the climatic pessimum. Solar activity, planetary factors and processes - volcanic activity, current intensity, heat transfer with the World Ocean – can noticeably strengthen or weaken both the manifestation of optimums and pessimums. The results of the study, taking into account other factors, can be used in the retroanalysis of the periods of glaciation in centuries before the Common Era and the prediction of them in the future.

Formation of frost boils in peat plateau of the Pur-Taz interfluve at the background of modern climate warming

In 2016-2017, we have detected numerous organic frost boils on the surface of khasyrey peat plateau in the southern tundra part of Pur-Taz interfluve (the north of West Siberia). They are related to the microrelief depressions in polygons and to the swales between tussocks. Cross-sections, cryogenic structure, properties of peat in active layer (moisture, density, heaving, chemical composition) and peat distribution within the khasyreys were studied. In the active layer, we distinguished soil and vegetation cover, upper and middle solid layers of weakly decomposed peat, lower layer of a well decomposed peat. Under the microrelief depressions, the top of permafrost is lowered, thickness and moisture of decomposed peat is increased due to the recent thawing in comparison to the elevated parts of polygons. In the cross-sections of seasonally thawing peat, we determined injections of organic matter from the lower layer of peat to the surface. We propose the mechanism of organic frost boils formation in peat plateau due to the injections during the summer seasons of 2016-2018 against the increase of a thaw depth without freezing. During the observation period, the amount of frost boils on polygonal peat plateau was found to increase.

Assessment of Modern Changes in Maximum River Flow in Russia

The long-term changes in annual maximum flow for the unregulated rivers of the Russian Federation are analyzed using data from 513 Roshydromet gaging stations. The following are evaluated: linear trends in the series of maximum river flow for the period of 1950–2016 and its statistical characteristics (mean values, variance, the number of years with the exceeding of the 10% probability maximum runoff) for two multiyear periods (the modern climate warming and the previous one). As a result, the zoning of the Russian territory is made according to the direction and intensity of modern changes in these parameters. The probability of historical maxima registered for the rivers at the beginning of the 21st century is estimated.

Влияние современных температурных колебаний на хозяйственную деятельность населения в Байкальском регионе

<span>В работе рассмотрена динамика ряда характеристик отопительного периода в многолетнем и межгодовом режиме на юге Байкальского региона. Выявлено сокращение продолжительности отопительного периода последних десятилетий (с 1991 по 2017 гг.) относительно многолетних данных до 1960 г. на 6–10 дней. Показан значительный рост температуры наружного воздуха в течение отопительного сезона на 3,9 °C в Чите, 4,1</span><span class="myHorizontalScaleForEmDashSpaceBefore"> </span><span>–</span><span class="myHorizontalScaleForEmDashSpaceAfter"> </span><span>в Иркутске и 5,0 °C</span><span class="myHorizontalScaleForEmDashSpaceBefore"> </span><span>–</span><span class="myHorizontalScaleForEmDashSpaceAfter"> </span><span>в Улан-Удэ. Совокупное изменение этих показателей повлияло на снижение индекса потребления топлива на 15–19%. Анализ межгодовых колебаний характеристик отопительного периода с 1991 г. по 2017 г. выявил, что аномально низкие температуры выше по модулю и отмечаются чаще по сравнению с аномально теплыми зимами. Изменение межгодовых колебаний индекса потребления топлива составило от 14–20%, что сопоставимо с многолетними колебаниями (до 1960 г.). Показано, что резкие межгодовые колебания температуры воздуха на фоне современного потепления демонстрируют неоднозначность их влияния на хозяйственную деятельность в Байкальском регионе.</span>

Evolution of the thermal state of permafrost under climate warming in Central Yakutia

The relevance of the problem under review is explained by the need to study the thermal response of permafrost to the modern climate change. Evolution of the thermal state of grounds has been studied with a view to evaluate the effects of modern climate warming on permafrost in Central Yakutia. The leading method to study this problem is the arrangement and performance of long-term monitoring observations of the permafrost thermal state that enable quantitative evaluation of the thermal response of upper permafrost layers to climatic fluctuations of recent decades. The analysis of long-term records from weather stations in the region has clearly revealed one of the highest increasing trends in the mean annual air temperature in northern Russia. Quantitative relationships in the long-term variability of ground thermal parameters, such as ground temperature at the bottom of the active layer, at the bottom of the annual heat exchange layer, and active thaw depth, have been established. The thermal state dynamics of the annual heat exchange layer under climate warming indicates that both warm and cold permafrost are thermally stable. Short-term variability of the snow accumulation regime is the main factor controlling the thermal state of the ground in permafrost landscapes. The active-layer thickness is characterized by low interannual variability and exhibits little response to climate warming, with no statistically meaningful increasing or decreasing trend. The results of ground thermal monitoring can be extended to similar landscapes in the region, providing a reliable basis for predicting heat transfer in natural landscapes.

Universal thermal climate index in Russia

The paper uses the universal thermal climate index (UTCI) to estimate the bioclimate in Russia, initiated by the Commission of the International society of Biometeorology. The UTCI index can be described as equivalent environment temperature (°C), which provides the same physiological impact on humans as the actual environment. Assessment of bioclimatic conditions is shown for the territory of Russia in the period of modern climate change (2001–2015). Cold stress conditions (from low to extreme) were observed in the almost all territory of Russia for about 8–11 months a year. During the rest of the year, the conditions are neutral or comfortable. The period of extreme and very high cold stress is reduced during the modern climate warming (compared to the period 1961–1990), especially in the Arctic, in the European part of Russia, in Western and Eastern Siberia. At the same time, the period with neutral and comfortable thermal conditions increases.

Empirical Predictability of Community Responses to Climate Change

Robust predictions of ecosystem responses to climate change are challenging. To achieve such predictions, ecology has extensively relied on the assumption that community states and dynamics are at equilibrium with climate. However, empirical evidence from Quaternary and contemporary data suggest that species communities rarely follow equilibrium dynamics with climate change. This discrepancy between the conceptual foundation of many predictive models and observed community dynamics casts doubts on our ability to successfully predict future community states. Here we used community response diagrams to empirically investigate the occurrence of different classes of disequilibrium responses in plant communities during the Late Quaternary, and bird communities during modern climate warming in North America. We documented a large variability in types of responses, suggesting that equilibrium dynamics are not the most common type of response to climate change. Bird responses appeared less predictable to modern climate warming than plant responses to Late Quaternary climate warming. Furthermore, we showed that baseline climate gradients were a strong predictor of disequilibrium states, while ecological factors such as species’ traits had a substantial, but inconsistent effect on the deviation from equilibrium. We conclude that (1) complex temporal community dynamics including stochastic responses, lags, and alternate states are common; (2) assuming equilibrium dynamics to predict biodiversity responses to future climate changes may lead to unsuccessful predictions

Natural and Bioclimatic Life Conditions of the Population of the Murmansk Oblast

Assessment of natural conditions and climatic resources of Murmansk oblast for the present time and climate modeling for the middle of the 21st century is provided. The trend of improvement of climatic conditions of population life under modern climate warming as well as for predicted climate change is shown. At mountains this improvement of climatic conditions will be slower than at plain. A decrease of bioclimatic conditions inclemency and an increase in the number of days suitable for active recreation (both in winter and in summer) will be observed. Murmansk oblast provides a wide variety of sanitary resources for urban development throughout the year, as well as recreational resources in the winter.

СОВРЕМЕННОЕ ПОТЕПЛЕНИЕ КЛИМАТА СЕВЕРНОГО И СЕВЕРО-ЗАПАДНОГО КЫРГЫЗСТАНА

СОВРЕМЕННОЕ ПОТЕПЛЕНИЕ КЛИМАТА СЕВЕРНОГО И СЕВЕРО-ЗАПАДНОГО КЫРГЫЗСТАНА

Ecological tree line history and palaeoclimate – review of megafossil evidence from the Swedish Scandes

The postglacial tree line and climate history in the Swedish Scandes have been inferred from megafossil tree remains. Investigated species are mountain birch (Betula pubescens ssp. czerepanovii), Scots pine (Pinus sylvestris) and grey alder (Alnus incana). Betula and Pinus first appeared on early deglaciated nunataks during the Lateglacial. Their tree lines peaked between 9600 and 9000 cal. a BP, almost 600 m higher than present‐day elevations. This implies (adjusted for land uplift) that early Holocene summer temperatures may have been 2.3°C above modern ones. Elevational tree line retreat characterized the Holocene tree line evolution. For short periods, excursions from this trend have occurred. Between c. 12 000 and 10 000 cal. a BP, a pine‐dominated subalpine belt prevailed. A first major episode of descent occurred c. 8200 cal. a BP, possibly forced by cooling and an associated shift to a deeper and more persistent snow pack. Thereafter, the subalpine birch forest belt gradually evolved at the expense of the prior pine‐dominated tree line ecotone. A second episode of pine descent took place c. 4800 cal. a BP. Historical tree line positions are viewed in relation to early 21st century equivalents, and indicate that tree line elevations attained during the past century and in association with modern climate warming are highly unusual, but not unique, phenomena from the perspective of the past 4800 years. Prior to that, the pine tree line (and summer temperatures) was consistently higher than present, as it was also during the Roman and Medieval periods, c. 1900 and 1000 cal. a BP, respectively.

Using paleolimnology to track Holocene climate fluctuations and aquatic ontogeny in poorly buffered High Arctic lakes

Fossil diatom assemblages, and spectrally-inferred dissolved organic carbon (DOC) and sedimentary chlorophyll-a (SedChla) were analysed on lake sediment cores from two poorly buffered lakes on Pim Island (High Arctic Canada) to assess their responses to Holocene climate changes and to document lake ontogeny. Following deglaciation, diatom assemblages were dominated by small benthic Fragilaria sensu lato taxa. During the mid-Holocene, there was an abrupt shift to more circumneutral and slightly acidophilous taxa dominated by Achnanthes and Navicula taxa. In the most recent sediments, we recorded an increase in the planktonic taxon Cyclotella radiosa. This shift of the last century is the most ecologically unique in the Holocene record and is indicative of longer ice-free summers consistent with modern climate warming. Inferred DOC and SedChla track some of the main Holocene climatic trends documented in the region, including the Holocene Thermal Maximum and Neoglacial period; however, changes in lakewater DOC did not likely drive any of the recorded shifts in diatom assemblages. Compared to nearby well-buffered sites, our poorly buffered lakes recorded a more dynamic diatom response to Holocene environmental change. The decreasing trend in diatom-inferred pH is likely due to changes in the acid neutralizing capacity (ANC) driven by the release of alkalinizing base cations from the easily weathered glacial deposits in the early Holocene and later by climate-driven pH dynamics and within-lake dissolved inorganic carbon (DIC) dynamics. The diatom community composition in our study lakes is different and undergoes greater changes than in nearby well-buffered lakes suggesting that softwater lakes in the high Arctic may respond most sensitively to climate and other environmental stressors.

The characteristics and regularities of the climate change over the past millennium in China

Research on global climate change has been at the frontier of the contemporary sciences. Discussion and debate about climate warming in the recent century has attracted the attention of the world. Debate has focused on whether the greenhouse effect produced by human activities is a major factor responsible for modern climate warming and whether the warming trend will persist in the future.

Seasonality of European warming: Influence of the tropics

This paper describes seasonal peculiarities of modern climate warming in the European region. It is shown that warming scenarios considerably differ in cold and warm periods of the year. The warming is accompanied with growth and considerable change in the phase of the yearly cycle in solarity data. A strong half-year cycle is recognized in seasonal variation of long-term trends over the last few years. Peculiarities of climate change in Europe and the increased influence of the tropics are discussed in view of the results obtained.

Indirect uptake of atmospheric CO2 by the ocean

During the last ten years, the reasons for modern global climate warming have been actively discussed. Many scientists consider the strengthening of the greenhouse effect to be the result of СО 2 introduction into the atmosphere, which is formed by burning of fuel mineral. At the end of the twentieth century and beginning of the twentyfirst century, the volume of anthropogenic СО2 outburst reached 7 billion tons C per year, which corresponds to 1% of the total СО 2 in the Earth's atmosphere. Observations demonstrate a lower rate of СО2 concentration increase in the atmo� sphere, and it is considered that the ocean absorbs 30- 50% of the anthropogenic outbursts of carbon dioxide (8, 9). In addition, there are arguments supporting the opposite point of view, according to which the ocean does not absorb, but, on the contrary, releases СО2 into the atmosphere (2, 7). The solution of this contra� diction should determine the direction and intensity of СО 2 exchange between the atmosphere and the ocean, which also may be directly applied to one of the funda� mental problems of geochemistry related to the study of the geochemical cycle of carbon in the biosphere. As a rule, СО2 exchange between the ocean and the atmosphere is studied on the basis of measurements and calculations of flows at the water-air boundary, without account for one more onesided relationship, including the transport of atmospheric СО2 to the ocean through a number of processes occurring on land and in totality called land runoff in the broad sense of this term. In this study we make an attempt to consider the geochemical mechanism of this process and its quantitative characteristics. The estimations given below are based on calcula� tions of the geochemical carbon balance in the ocean (2) confirmed indirectly in (3). Although the character of geochemical information available does not allow us to apply the methods of mathematical statistics to determine the accuracy of estimations of carbon flows, their accuracy may be judged from comparison of the results of different works. Calculations of carbon flows (2) providing the most complete account of the terrig� enous carbon runoff are usually consistent with esti� mations of flow values obtained by other authors (10) within 30-50%, which may most likely be considered as their accuracy. The land runoff of dissolved and solid compounds is one of the main incoming positions of the carbon geochemical balance in the ocean, and various carbon forms have different geneses. Dissolved organic carbon and most of the sus� pended organic carbon are the products of photosyn� thesis of land plants using atmospheric СО2 trans� formed to one degree or another: