Summer Air Temperature Research Articles

Natural Intertidal Oyster Reef Growth Across Two Landscape Settings and Tidal Ranges

Intertidal oyster reefs are typically restored to offset the loss of reef-associated ecosystem services (e.g., improved water quality, shoreline stabilization, and fish habitat), but the scale of enhanced services is predicated on the health and growth of the restored reef. Previous work on young (<15 years) restored reefs showed the highest growth rates along the sides of reefs where they are aerially exposed 20–40% of the time, but much is still unknown about how those positions in the tidal frame change with landscape setting, tidal range, and reef maturity. This study compared the area of maximum growth among 12 natural intertidal reefs in coastal North Carolina that range between 1395 and 62 years old. The reefs include fringing and patch landscape settings in each of two estuaries with tidal ranges of 0.94 m and 1.51 m. Peak growth rates were similar among landscape and tidal settings and were faster than the rate of sea-level rise (SLR) indicating intertidal reef resilience to accelerating SLR. Flow baffling associated with fringing reefs and higher summer air temperatures in the southern estuary likely contributed to a lower position of the optimal growth zone, where growth rates are highest, in the tidal frame. Intertidal reef growth manifests differently across the range of aerial exposures at varying stages of maturity. Once reefs reached ~50 years old, the elevation of the reef crests equilibrated to ~60–70% aerial exposure and peak growth rates stabilized between 2 and 4 cm year−1 at ~50% aerial exposure. These results are a useful guide for identifying areas and cultch configurations that optimize reef growth rates, enhancing the probability for self-sustaining restored reefs.

Зонирование административных районов российской Арктики по степени опасности разрушения скотомогильников в результате деградации многолетней мерзлоты

Climatic changes have already resulted and will continue to result in gradual degradation of active upper layers in permafrost due to increased average air temperature in summer. Anthrax is an example of a climate-depending bacterial infection; anthrax agent creates spores that remain viable for a long period of time they spend in cryptobiosis in permafrost. Apparent permafrost degradation is already detected in most arctic regions in Russia and it can lead to anthrax burials decay thus creating elevated risks of the infection among farm animals and people who live on these territories. Our research goal was to create specific zones in municipal districts via combining data on permafrost, number of anthrax cattle burials, ascending trends in average long-term temperatures, and population density. We developed two relative hazard coefficients for characterizing anthrax outbreaks probability for animals and local population. Basing on numeric values obtained for these two coefficients, 70 administrative districts located in 15 RF subjects in the Arctic zone were listed in a descending order as per risks of the infection occurrence. We created two score scales showing relative hazard; they indicated that the highest population risk was typical for urban districts as population density there was much high than in rural ones. Our calculations should be helpful for determining priorities when preventive activities are developed on arctic and sub-arctic territories that are endemic as per anthrax. It is also important to obtain an actual list of cattle burials and to develop spatial-time models showing anthrax outbreaks occurrence taking into account climatic warming and permafrost degradation.

Creating zones in administrative districts located in the Russian arctic region specific as per threats of cattle burials decay due to permafrost degradation

Climatic changes have already resulted and will continue to result in gradual degradation of active upper layers in permafrost due to increased average air temperature in summer. Anthrax is an example of a climate-depending bacterial infection; anthrax agent creates spores that remain viable for a long period of time they spend in cryptobiosis in permafrost. Apparent permafrost degradation is already detected in most arctic regions in Russia and it can lead to anthrax burials decay thus creating elevated risks of the infection among farm animals and people who live on these territories. Our research goal was to create specific zones in municipal districts via combining data on permafrost, number of anthrax cattle burials, ascending trends in average long-term temperatures, and population density. We developed two relative hazard coefficients for characterizing anthrax outbreaks probability for animals and local population. Basing on numeric values obtained for these two coefficients, 70 administrative districts located in 15 RF subjects in the Arctic zone were listed in a descending order as per risks of the infection occurrence. We created two score scales showing relative hazard; they indicated that the highest population risk was typical for urban districts as population density there was much high than in rural ones. Our calculations should be helpful for determining priorities when preventive activities are developed on arctic and sub-arctic territories that are endemic as per anthrax. It is also important to obtain an actual list of cattle burials and to develop spatial-time models showing anthrax outbreaks occurrence taking into account climatic warming and permafrost degradation.

An overview of Holocene climate reconstructions in northernmost Fennoscandia

An overview of climate reconstructions considering summer air temperatures and effective precipitation is provided for northernmost Fennoscandia. During the earliest part of the Holocene (11,700–10,000 cal. BP), temperatures rose rapidly and were followed by mild, wet and variable conditions. An early major warming peaked around 9500 cal. BP, although many records indicate that the main Holocene warming first occurred about c. 8000 cal. BP. The sub-regional pattern of climate change suggests a defining influence of the westerlies and the North Cape Current. Non-analog climatic conditions and lags in vegetation responses to climate change may explain some of the discrepancies seen in the early Holocene between proxies. In contrast to the perceivable variable onset of the main Holocene warm period, maximum temperatures are relatively consistent between the records, indicating temperatures 1.5±0.5°C above present. Precipitation was generally high from 10,000 cal. BP but decreased towards 8000 cal. BP when dry climatic conditions became predominant. After a stable period 8000–6000 cal. BP a gradual cooling was initiated, with a more abrupt period of change 4500–3800 cal. BP when the warm and dry climate of the mid-Holocene changed into the cool, wet and unstable climate of the late Holocene. Modern conditions were reached c. 2800 cal. BP. The Holocene Thermal Maximum may be defined several different ways: as temperatures distinctly above modern delimited to 9500–4000 cal. BP; as peak temperatures 9500–6000 cal. BP; and/or as climax vegetation in the period 8000–4000 cal. BP. Prior to 8000 cal. BP vegetation probably lagged behind the warming, whereas in the period 8000–4000 cal. BP an equilibrium between climate and vegetation was established.

Distributed summer air temperatures across mountain glaciers in the south-east Tibetan Plateau: temperature sensitivity and comparison with existing glacier datasets

Abstract. Near-surface air temperature (Ta) is highly important for modelling glacier ablation, though its spatio-temporal variability over melting glaciers still remains largely unknown. We present a new dataset of distributed Ta for three glaciers of different size in the south-east Tibetan Plateau during two monsoon-dominated summer seasons. We compare on-glacier Ta to ambient Ta extrapolated from several local off-glacier stations. We parameterise the along-flowline sensitivity of Ta on these glaciers to changes in off-glacier temperatures (referred to as “temperature sensitivity”) and present the results in the context of available distributed on-glacier datasets around the world. Temperature sensitivity decreases rapidly up to 2000–3000 m along the down-glacier flowline distance. Beyond this distance, both the Ta on the Tibetan glaciers and global glacier datasets show little additional cooling relative to the off-glacier temperature. In general, Ta on small glaciers (with flowline distances &lt;1000 m) is highly sensitive to temperature changes outside the glacier boundary layer. The climatology of a given region can influence the general magnitude of this temperature sensitivity, though no strong relationships are found between along-flowline temperature sensitivity and mean summer temperatures or precipitation. The terminus of some glaciers is affected by other warm-air processes that increase temperature sensitivity (such as divergent boundary layer flow, warm up-valley winds or debris/valley heating effects) which are evident only beyond ∼70 % of the total glacier flowline distance. Our results therefore suggest a strong role of local effects in modulating temperature sensitivity close to the glacier terminus, although further work is still required to explain the variability of these effects for different glaciers.

Temperature and water depth effects on brGDGT distributions in sub-alpine lakes of mid-latitude North America

Branched glycerol dialkyl glycerol tetraethers (brGDGTs) in lake sediments are increasingly being used to reconstruct past temperatures. However, recent studies suggest that brGDGT distributions and concentrations vary with lake size and environmental conditions, such as seasonality and its effects on water column temperature and chemistry. To test their use as a paleothermometer in high-altitude environments of mid-latitude North America, we analyzed brGDGT distributions in lake surface sediments across a range of lake depths and elevations in the Rocky Mountains of Wyoming and Colorado. Our results suggest that brGDGT distributions and the MBT′5Me index correlate with water column temperatures, which are sensitive to both lake water depth and air temperatures. Based on these relationships, we developed a calibration to mean summer air temperatures using a Bayesian regression model that incorporates the MBT′5Me index and lake water depth. We applied our calibration to lake sediments from Lower Paintrock Lake in northern Wyoming to test its use as a paleothermometer. Reconstructed temperature trends are consistent with pollen-inferred temperatures at the same site and with known regional climate history, demonstrating that our calibration can be successfully applied to infer temperatures in high-altitude environments of mid-latitude North America.

Long-term ice-rich permafrost coast sensitivity to air temperatures and storm influence: lessons from Pullen Island, Northwest Territories, Canada

Response of erosive mechanisms to climate change is of mounting concern on Beaufort Sea coasts, which experience some of the highest erosion rates in the Arctic. Collapse of intact permafrost blocks and slumping within sprawling retrogressive thaw complexes are two predominant mechanisms that manifest as cliff retreat in this region. Using aerial imagery and ground survey data from Pullen Island, Northwest Territories., Canada, from 13 time points between 1947 and 2018, we observe increasing mean retreat rates from 0 ± 4.8 m a−1 in 1947 to 12 ± 0.3 m a−1 in 2018. Mean summer air temperature was positively correlated with cliff retreat over each time step via block failure (r2 = 0.08; p = 0.5) and slumping (r2 = 0.41; p = 0.05), as was mean storm duration with cliff retreat via block failure (r2 = 0.84; p = 0.0002) and slumping (r2 = 0.34; p = 0.08). These data indicate that air temperature has a greater impact in slump-dominated areas, whereas storm duration has greater control in areas of block failure. Increasingly, heterogeneous cliff retreat rates are likely resulting from different magnitudes of response to climate trends depending on mechanism, and on geomorphological variations that prescribe occurrences of retrogressive thaw slumps.

Evaluation of the carrot gene pool for yield and quality indicators at Volgograd Experiment Station of VIR

The Volga-Akhtuba Floodplain is among the areas with insufficient rainfall, where high air temperatures in summer are coupled with low humidity. An urgent task is to select carrot cultivars adapted to irrigated cultivation conditions. For this purpose, 101 carrot accessions of diverse origin were studied at Volgograd Experiment Station. The study was accomplished according to the guidelines developed by VIR.The tested carrot accessions demonstrated different responses to abrupt changes in the temperature and water regimes. At the same time, differences were found in the yield and quality of roots. An important indicator was the stability of root yield. High-yielding cultivars with relatively stable yields were identified: ‘Nesravnennaya’ (k-1528, Russia), ‘Leninakanskaya’ (k-1936, Armenia), ‘Asmer Early market’ (k-2304, UK), and ‘Konservnaya-63’ (k-2320, Moldova). High yields and good marketability were shown by cvs. ‘Nantes’ (k-1438, Bulgaria), ‘Leninakanskaya’ (k-1936, Armenia), ‘Danvers’ (k-2167, USA), ‘Konservnaya-63’ (к2320, Moldova), ‘All Season’ (k-2598, Australia), and ‘Rogneda’ (k-2611, Russia). These cultivars originated mostly from arid areas. The content of chemical compounds in roots was highly variable, depending on the cultivar (hybrid) and, in particular, on the growing conditions. For example, the sugar content ranged from 3.0 to 6.85%, ascorbic acid from 7.9 to 12.2 mg/100 g, and carotene from 9.5 to 17.9 mg/100 g. The tests revealed a considerable variability in main agronomic characters of the carrot accessions, especially when high-yielding cultivars were concerned: they were the most sensitive to cultivation in arid environments and suffered a decrease in marketability. As a result of the study, carrot accessions combining high yield, good marketability and beneficial chemical composition were identified. They are promising for breeding programs aimed at the development of cultivars adaptable to high summer temperatures and low humidity.

Оптимизация продуктивности гибридов подсолнечника с применением различных доз минеральных удобрений в рисовых чеках Калмыкии

In the issue of increasing yield of sunflower seeds, the correct selection of hybrids in relation to specific soil and climatic conditions is of great concern. Each hybrid under study has its own productivity potential determined by its genotypic features. The soil and climate conditions of the Republic of Kalmykia allow to obtain 0.98...1.71 tons of hybrid sunflower seeds per hectare in terms of residual moisture after rice (280-300mm) with the correct combination of basic agricultural techniques. It is detected that there are patters of the influence of various doses of mineral fertilizers on the growth, development and formation of sunflower seed yield are established Keywords: RICE CROP ROTATION, SUNFLOWER, MINERAL FERTILIZERS, SUM OF ACTIVE AIR TEMPERATURES, VIABILITY, CROP YIELD, OIL CONTENT

SANATORIUM-PREVENTION «MOUNTAIN WATER» (TO THE QUESTION OF DEVELOPMENT OF THE HEALTH RESORT BASE OF PRIMORSKY KRAI)

The article provides a mention of the Russian Soviet geographer and traveler V. K. Arsenyev about mineral springs in the Ussuri taiga, briefly outlines the history of the opening of a sanatorium in Gornovodny (Sandagou). The role of the command of the Vladimir-Olginsky military naval base of the Pacific Fleet in the opening of the sanatorium is highlighted (information from the book of the graduate of the Naval Medical Academy, captain of the medical service A. M. Kopanev was used), as well as the study and application in the treatment of patients with mineral water by a naval doctor the therapeutic department of the 18th Naval Hospital of the 750th Logistics Department of the Pacific Fleet, Lieutenant Colonel of the Medical Service I. F. Andreev. The main characteristics, chemical formula and chemical composition of mineral water from the Gornovodnoye spring are given. The medical base, profiles of diseases, accommodation, nutrition, recreation, summer and winter outdoor air temperatures are presented.

Indoor Daylighting and Thermal Response of a Passive Solar Building to Selective Components of Solar Radiation

Solar radiation provides the most significant natural energy in buildings for space heating and daylighting. Due to atmospheric interference, solar radiation received at the Earth’s surface consists of direct beam and diffuse radiation, where diffuse can be further broken down into longwave and visible radiation. Although each of these components co-occurs, their influence on the indoor visual and thermal conditions of a building differ. This study aims to analyze the influence of the various components of solar radiation on the indoor thermal and daylighting of a passive solar building. Thus, a pyrheliometer, pyranometer, shaded-pyranometer, and pyrgeometer mounted on a SOLYS 2 (Kipp &amp; Zonen, Delft, Netherlands) dual Axis sun tracker, were used to monitor direct, global horizontal, diffuse and downward longwave radiation, respectively. The seasonal indoor air temperature and relative humidity were measured using an HMP 60 temperature relative humidity probe. A Li-210R photometric sensor was used to monitor the indoor illuminance. The summer and winter indoor air temperature, as well as relative humidity, were found to be influenced by diffuse horizontal and global horizontal irradiance, respectively. In summer, the indoor air temperature response to diffuse horizontal irradiance was 0.7 °C/ħW/m2 and 1.1 °C/ħW/m2 to global horizontal irradiance in winter, where ħ is 99.9 W/m2. The indoor daylighting which was found to be above the minimum office visual task recommendation in most countries, but within the useful daylight illuminance range was dominated by direct normal irradiance. A response of 260 lux/ħW/m2 was observed. The findings of the study support the strategic locating of the windows in passive solar design. However, the results show that north-facing clerestory windows without shading device could lead to visual discomfort.

Experimental Study of Thermal Comfort Based on Driver Physiological Signals in Cooling Mode under Summer Conditions

In this study, electroencephalogram (EEG), photo-plethysmography (PPG), and surface temperature measurements of subjects were taken while performing a driving simulation when the cabin and vent discharge air temperature in summer were changed from discomfort to comfort conditions. Additionally, subjective questionnaires were used to analyze the subject’s thermal comfort under the various driving environments. As a result, the surface temperatures of the forehead, left hand, right hand, and abdomen of the subject during driving were reduced by 2, 0.97, 2.18, and 5.86 °C, respectively, by operating a 12.5 °C vent cooling function at a cabin temperature of 35 °C. As a comprehensive analysis of the subjective survey, PPG, and EEG results, total power (TP), the standard deviation of N-N interval (SDNN), and the root mean square of successive differences (RMSSD) of subjects increased and stress index decreased at cabin and vent discharge air temperatures of 30–27.5 °C and 16.5–18.5 °C, respectively. Furthermore, the relative sensory motor rhythm (SMR) wave and concentration index (CI) of the frontal lobe tended to increase under the same temperature conditions. Accordingly, it was confirmed that these temperature conditions provided a pleasant driving environment for the driver and increased concentration on driving.

Resilience in Greenland intertidal Mytilus: The hidden stress defense

The Arctic is experiencing particularly rapid rates of warming, consequently invasive boreal species are now able to survive the less extreme Arctic winter temperatures. Whilst persistence of intertidal and terrestrial species in the Arctic is primarily determined by their ability to tolerate the freezing winters, air temperatures in the Arctic summer can reach 36 °C in the intertidal, which is beyond the upper thermal limits of many marine species. This is normally lethal for the conspicuous ecosystem engineer Mytilus edulis. Transcriptomic analyses were undertaken on both in situ collected and experimentally warmed animals to understand whether M. edulis is able to tolerate these very high summer temperatures. Surprisingly there was no significant enrichment for Gene Ontology terms (GO) when comparing the inner and outer fjord intertidal animals with outer fjord subtidal (control) animals, representing animals collected at 27 °C, 19 °C and 3 °C respectively. This lack of differentiation indicated a wide acclimation ability in this species. Conversely, significant enrichment for processes such as signal transduction, cytoskeleton and cellular protein modification was identified in the expression profiles of the 22 °C and 32 °C experimentally heated animals. This difference in gene expression between in situ collected and experimentally warmed animals was almost certainly due to the former being acclimated to a fluctuating, but predictable, temperature regime, which has increased their thermal tolerances. Interestingly, there was no evidence for enrichment of the classical cellular stress response in any of the animals sampled. Identification of a massive expansion of the HSPA12 heat shock protein 70 kDa gene family presented the possibility of these genes acting as intertidal regulators underpinning thermal resilience. This expansion has resulted in a modified cellular stress response, as an evolutionary adaptation to the rigour of the invasive intertidal life style. Thus, M. edulis appear to have considerable capacity to withstand the current rates of Arctic warming, and the very large attendant thermal variation.

Detecting Tree Species Effects on Forest Canopy Temperatures with Thermal Remote Sensing: The Role of Spatial Resolution

Canopy temperatures are important for understanding tree physiology, ecology, and their cooling potential, which provides a valuable ecosystem service, especially in urban environments. Linkages between tree species composition in forest stands and air temperatures remain challenging to quantify, as the establishment and maintenance of onsite sensor networks is time-consuming and costly. Remotely-sensed land surface temperature (LST) observations can potentially acquire spatially distributed crown temperature data more efficiently. We analyzed how tree species modify canopy air temperature at an urban floodplain forest (Leipzig, Germany) site equipped with a detailed onsite sensor network, and explored whether mono-temporal thermal remote sensing observations (August, 2016) at different spatial scales could be used to model air temperatures at the tree crown level. Based on the sensor-network data, we found interspecific differences in summer air temperature to vary temporally and spatially, with mean differences between coldest and warmest tree species of 1 °C, and reaching maxima of up to 4 °C for the upper and lower canopy region. The detectability of species-specific differences in canopy surface temperature was found to be similarly feasible when comparing high-resolution airborne LST data to the airborne LST data aggregated to 30 m pixel size. To realize a spatial resolution of 30 m with regularly acquired data, we found the downscaling of Landsat 8 thermal data to be a valid alternative to airborne data, although detected between-species differences in surface temperature were less expressed. For the modeling of canopy air temperatures, all LST data up to the 30 m level were similarly appropriate. We thus conclude that satellite-derived LST products could be recommended for operational use to detect and monitor tree species effects on temperature regulation at the crown scale.

Restoration of woodland belts and sustainable development of agroecosystems of steppe zone of the Orenburg oblast (Russia)

Orenburg oblast is situated in the steppe zone. The climate is continental, characterized by a large amplitude of fluctuations in both summer and winter air temperatures, and insufficient precipitation. Due to such low climate potential, the development of agricultural production in the region needs constant improvement (increasing soil fertility, erosion control, planting sustainable crops). Therefore, optimization of agricultural production in order to restore the productive potential of land is one of the most actual problems in the region. Orenburg oblast due to its geographical location is characterized by dry winds, which not only dry up the soil, but also sharply reduce its fertility, effect on the water balance, and reduce yield. Therefore, the creation of forest protection treestands in this case is a priority method that contributes to the preservation of soil fertility in the region and, consequently, to the increased rate of agricultural production. In this article, we consider some species of plants belonging to the genera Sorbus L., Crataegus L., Aronia Pers., Syringa L., which have a number of positive ecological and biological characteristics, compared to plants that are widely used in forest protection plantations in the region today (Betula pendula Roth., Pinus sylvestris L., etc.). Using plants that have significant advantages in creating protective forests, it becomes possible to solve the problem of sustainable development of the land fund, and, consequently, to increase the rate of agricultural production. This will allow regulating land use processes not only at the regional level, but also at the state level.

РЕКОНСТРУКЦИЯ БАЛАНСА МАССЫ ЛЕДНИКА САРЫ-ТОР ПО МЕТЕОРОЛОГИЧЕСКИМ ДАННЫМ

Mass balance bn is the most important indicator of a glacier evolution. However, after the decay of the USSR direct measurements of bn performed in 1985–1989 in the Inner Tien Shan, including the Sary-Tor Glacier in Ak-Shiyrak Massif, had been desisted. As a result the available series of the data were limited 1989. Measurements in this area were renewed only in 2015. This paper is devoted to restoring the continuity of the mass-balance series over the period of the gap in measurements and extending this series down to 1929, i.e. to the beginning of regular meteorological observations on the reference HMS Tien Shan (3660 m a.m.s.l.). Accumulation was reconstructed using a linear relationship of bn with the air temperature and precipitation sum. Reconstruction of ablation was based on its cubic relationship with the temperature (modified Krenke– Khodakov formula) or on two-parameter linear approximation using the air temperature and wind velocity. Thereby, the decade of direct instrumental measurements (1984/85–1988/89 and 2014/15–2018/19) resulted in deriving and analyzing continuous 90-year-long series of annual values of bn and its constituents, analytical type of referent glacio-meteorological equations being assumed unchanged in time. Reconstruction for the Sary-Tor Glacier reveals a dominant trend towards the mass loss with rare and short-time episodes of retarding the negative tendencies. The comparison made with the long series of mass balance of other glaciers in Asia indicates a certain degree of synchronicity, which is slightly disturbed in recent years: the degradation of Sary Tor Glacier tends to progress more intensively. Conclusions about its evolution are particularly relevant in connection with the assumption about the impact of the Kyrgyz-Canadian gold mining company «Kumtor Gold Company» on local ecosystems against the background of its interest in expanding the mining zone to the bowels of the Earth under the tongue of this glaciological object.

Past Warmth and Its Impacts During the Holocene Thermal Maximum in Greenland

Higher boreal summer insolation in the early to middle Holocene drove thousands of years of summer warming across the Arctic. Modern-day warming has distinctly different causes, but geologic data from this past warm period hold lessons for the future. We compile Holocene temperature reconstructions from ice, lake, and marine cores around Greenland, where summer temperatures are globally important due to their influence on ice sheet mass balance, ocean circulation, and sea ice. Highlighting and accounting for some key issues with proxy interpretation, we find that much of Greenland experienced summers 3 to 5°C warmer than the mid-twentieth century in the early Holocene—earlier and stronger warming than often presumed. Warmth had dramatic consequences: Many glaciers disappeared, perennial sea ice retreated, plants and animals migrated northward, the Greenland Ice Sheet shrank rapidly, and increased meltwater discharge led to strong marine water stratification and enhanced winter sea ice in some areas. ▪ Summer air temperatures and open ocean temperatures around much of Greenland peaked in the early Holocene in response to elevated summer insolation. ▪ Peak summer air temperatures ranged from 3 to 5°C warmer than the mid-twentieth century in northwest and central Greenland to perhaps 1 to 2°C warmer in south Greenland. ▪ Many differences between records can be explained by proxy seasonality, ice sheet elevation changes, vegetation analogs and lags, and the nearshore effects of ice sheet meltwater. ▪ Early Holocene warmth dramatically affected glaciers and the Greenland Ice Sheet; meltwater discharge, nearshore ocean salinity, and sea ice; and diverse flora and fauna.

New insights into lake responses to rapid climate change: the Younger Dryas in Lake Gościąż, central Poland

The sediment profile from Lake Gościąż in central Poland comprises a continuous, seasonally resolved and exceptionally well‐preserved archive of the Younger Dryas (YD) climate variation. This provides a unique opportunity for detailed investigation of lake system responses during periods of rapid climate cooling (YD onset) and warming (YD termination). The new varve record of Lake Gościąż presented here spans 1662 years from the late Allerød (AL) to the early Preboreal (PB). Microscopic varve counting provides an independent chronology with a YD duration of 1149+14/–22 years, which confirms previous results of 1140±40 years. We link stable oxygen isotopes and chironomid‐based air temperature reconstructions with the response of various geochemical and varve microfacies proxies especially focusing on the onset and termination of the YD. Cooling at the YD onset lasted ~180 years, which is about a century longer than the terminal warming that was completed in ~70 years. During the AL/YD transition, environmental proxy data lagged the onset of cooling by ~90 years and revealed an increase of lake productivity and internal lake re‐suspension as well as slightly higher detrital sediment input. In contrast, rapid warming and environmental changes during the YD/PB transition occurred simultaneously. However, initial changes such as declining diatom deposition and detrital input occurred already a few centuries before the rapid warming at the YD/PB transition. These environmental changes likely reflect a gradual increase in summer air temperatures already during the YD. Our data indicate complex and differing environmental responses to the major climate changes related to the YD, which involve different proxy sensitivities and threshold processes.

Stable isotopes in cave ice suggest summer temperatures in east-central Europe are linked to Atlantic Multidecadal Oscillation variability

Abstract. The climate of east-central Europe (ECE) is the result of a combination of influences originating in the wider North Atlantic realm, the Mediterranean Sea, and the western Asian and Siberian regions. Previous studies have shown that the complex interplay between the large-scale atmospheric patterns across the region results in strongly dissimilar summer and winter conditions on timescales ranging from decades to millennia. To put these into a wider context, long-term climate reconstructions are required, but, largely due to historical reasons, these are lacking in ECE. We address these issues by presenting a high-resolution, radiocarbon-dated record of summer temperature variations during the last millennium in ECE, based on stable isotope analysis of a 4.84 m long ice core extracted from Focul Viu Ice Cave (Western Carpathians, Romania). Comparisons with both instrumental and proxy-based data indicate that the stable isotope composition of cave ice records the changes in summer air temperature and has a similar temporal evolution to that of the Atlantic Multidecadal Oscillation on decadal to multidecadal timescales, suggesting that changes in the North Atlantic are transferred, likely via atmospheric processes towards the wider Northern Hemisphere. On centennial timescales, the data show little summer temperature differences between the Medieval Warm Period (MWP) and the Little Ice Age (LIA) in eastern Europe. These findings are contrary to those that show a marked contrast between the two periods in terms of both winter and annual air temperatures, suggesting that cooling during the LIA was primarily the result of wintertime climatic changes.

Outdoor environmental investigation of old communities during summer in hot summer and cold winter regions

The outdoor physical environments of many old communities are unable to meet modern living requirements and require improvement urgently. This is especially true for communities in regions with extremely hot summers and cold winters, which may cause additional difficulties. This study used measurements and questionnaire data to investigate outdoor environment (the thermal, sound, light environments and air quality) and resident sensations in four such communities. Results revealed some key factors affecting outdoor environmental comfort, including summer shading, winter sunlight, air temperature, air quality, the sound environment and odour. The results also revealed that the main problems were noise, insufficient illumination and high air temperatures in summer, all of which had seriously affected comfort during outdoor activities. Specifically, noise values during the most unfavourable periods were between 57.4 and 80.6 dB(A), while average air temperatures were between 32.3°C and 35.8°C, and average illuminances were below 2.9 lx. As such, this paper proposes improvement measures such as sound barriers and greening. Further, we propose a method for prioritizing these factors for such improvements based on a combination of subjective and objective factors. This study provides data and technical references for the reconstruction of old communities in regions with hot summers and cold winters.