Warm Humid Climate Research Articles

Thermal performance of green balconies of residential buildings: A Case Study in Wari, Dhaka

This study investigates the impact of green balconies on the thermal performance and indoor environmental quality of residential buildings in Dhaka, Bangladesh, which experiences a warm-humid climate year-round. Green balconies, incorporating vertical landscaping or potted plants are evaluated for their potential to reduce indoor temperatures, enhance thermal comfort, and contribute to energy savings. Field measurements were conducted in a high-rise residential building, with data collected on indoor temperatures, relative humidity, and solar radiation for both green and non-green balconies. Results show that green balconies can reduce indoor air temperatures by up to 6.5 °C, with an average reduction of 3.0°C in room temperature, compared to non-green balconies. The presence of greenery effectively mitigates heat gain, particularly through evapotranspiration and shading, improving thermal comfort and reducing reliance on mechanical cooling systems. Additionally, green balconies contribute to energy efficiency, with potential energy savings of up to 20%. The study further emphasizes the importance of optimal design, including the use of densely arranged potted plants, to maximize the cooling effect. This research highlights the effectiveness of green balconies as a passive cooling strategy for tropical climates, offering sustainable solutions for residential buildings by improving both environmental and occupant well-being.

Design optimisation for embodied carbon and thermal performance of a courtyard house in the warm–humid climate of Ghana

Design optimisation for embodied carbon and thermal performance of a courtyard house in the warm–humid climate of Ghana

MINERALOGICAL, PETROGRAPHIC, AND LITHOCHEMICAL FEATURES OF THE UPPER JURASSIC–LOWER CRETACEOUS SECTION OF THE NORDVIK PENINSULA (NORTH OF EASTERN SIBERIA)

Some intervals of the Jurassic–Cretaceous strata of the Anabar-Lena sedimentary basin have a certain oil and gas production potential, which can be realized in the synchronous offshore horizons of the adjacent territories of the Arctic shelf. Among the most representative objects in this regard are the outcrops of Upper Jurassic and Lower Cretaceous formations of the Nordvik Peninsula. The main data on the composition and structure of this section were obtained mainly at the beginning of the second half of last century. The results of complex mineralogical, petrographic, and lithochemical studies of the Urdyuk-Khaya and Paksa formations of Cape Urdyuk-Khaya of the Nordvik Peninsula presented in here enabled us to identify 10 boundaries for changing of sedimentation regimes of the paleobasin. It was found that the Urdyuk-Khaya Formation was formed mainly in the conditions of the shelf transition zone (moderate deep water) with low rates of terrigenous material intake, some depletion of oxygen in bottom waters, and a trend towards an increase in the depths of the basin. The basal stratum of the Paksa Formation was formed in offshore conditions with periodically occurring dioxic conditions in bottom waters and extremely low rates of terrigenous material intake. The overlying part of the formation was formed in various parts of offshore transition conditions with a gradual decrease in the depths of the basin, an increase in the oxygen content in the bottom layer of water, and the rate of terrigenous material intake. The main provenance area was igneous rocks of mafic, possibly intermediate composition. There was some influence of felsic igneous rocks, or ancient sedimentary rocks rich in quartz. The parent strata were subjected to moderate and severe chemical weathering, in a warm humid climate. The revealed features of the studied strata are similar to the characteristics of the same-age sediments of the lower reaches of the Anabar River, which determines their high correlation potential and allows us to judge the evolution of the western part of the Anabar-Lena basin.

Traditional and contemporary building thermal sensations prediction models in a warm-humid climate

ABSTRACT Passive ways of providing thermal comfort have been intensively researched in many nations. Despite researchers’ strenuous efforts, most studies on thermal comfort concerns are centred on continents such as Asia, America, Europe, and Africa, with a handful of studies comparing building types in the sub-Saharan area. However, none has focused on statistical models to predict the thermal sensations of occupants in traditional and modern structures during the dry season. Hence, this study investigated interior relative humidity, air temperature, and occupants’ thermal feelings in traditional and modern structures in the dry season in Okigwe, Nigeria. The data for this investigation was collected by physically measuring relative humidity and air temperature using data loggers. A longitudinal survey technique was also used to elicit answers from the residents of the selected traditional and modern structures on the thermal feeling of comfort temperature. To predict the inhabitants’ thermal sensations in the building types investigated, two statistical models were developed: ‘TSVt = 0.65 (MITt) – 13.5’ for traditional structures and ‘TSVc = 0.74 (MITc) – 16’ for modern. The comfort range and neutral temperature of ‘3.15 ≤ TSV ≤ 4.85’ 1–7 yielded 26.8°C as the neutral temperature for the occupants of traditional buildings, with the comfort ranging between 25.6°C and 28.2°C. Contemporary building occupants’ neutral temperature and comfort ranges from 25.9°C to 28.2°C. The study therefore recommended the use of the developed models by Architects, Planners, and Designers for predicting the occupants’ sensations of the building types before preliminary investigations and design sketches, as with such information, the designer possesses the necessary tools for providing buildings that are thermally comfortable for maximum comfort and minimal consumption of energy.

Correction: Kurian et al. Estimation of Carbon Footprint of Residential Building in Warm Humid Climate of India through BIM. Energies 2021, 14, 4237

There was an error in the original publication [...]

PASSIVE DESIGNS AND THERMAL PERFORMANCE OF THE TEMPLES IN THE WARM-HUMID CLIMATIC ZONE OF SOUTH INDIA

Religious beliefs, traditional wisdoms, rituals, and cultural practices all play an important part in environmental and biodiversity protection. Conservation of environment and natural resources has long been an element of cultural ethics that can be observed in the vernacular architecture of India, practiced in different parts of the country. The Indian Temple architecture is a manifestation of these socio-cultural-environmental values which are conceptualized and constructed in unique ways integrating passive features which keeps on educating and inspiring generations after generations. These timeless Temples through their passive architectural elements and harmonic aesthetic qualities enable the societies to perceive themselves as part of a spiritual network and to connects them to their biophysical surroundings. Hence, the present research explores the passive architectural features and thermal performance of the naturally ventilated south Indian Temples, located in warm and humid climate zone, and how these passive features can be implemented in the present day’s buildings to achieve thermal comfort. The research deploys a qualitative descriptive comparative analysis method. It delves into case studies of two Temples located in Kerala, having warm-humid climate, to investigate the passive architectural features and thermal performance. Data collection is done through field visits to these two Temples: Iringole Kaavu Bhagavathy Temple (old) and Thottuva Temple (new). Measurements of environmental parameters are also collected during field-surveys. The study concludes that the adaptation of passive architectural features, in response to the local climatic conditions, are paramount and beneficial to improve the thermal performance of the structures and thermal comfort of the users. Hence, it is argued that the passive climate-responsive architectural features of the south Indian Temples, suitable to the local geoclimatic and cultural conditions, need to be continued to follow in the present and future generation of buildings.

Response of aquatic ammonia-oxidizing archaea to thermal stratification and nutrient levels since the Last Glacial Maximum in the deep lake Fuxian, southwestern China

Ammonia-oxidizing archaea (AOA) are the critical nitrifier in lake ecosystems and participate in the global nitrogen cycle. However, the response of aquatic AOA to long-term climate change remains unclear. Here, we obtained a continuous sediment record from a deep, oligotrophic lake (Lake Fuxian, China) and reconstructed changes in AOA productivity over the past 26 thousand years (cal ka BP) using a multi-proxy approach. AOA productivity (estimated using diagnostic archaeal lipids) was low during the Last Glacial Maximum (LGM) before peaking during the cold-dry Heinrich event 1 (H1, 17.7–15.9 cal ka BP). As the Indian Summer Monsoon (ISM) intensified and the climate became warmer and wetter, aquatic AOA productivity progressively declined. We show that a combination of factors modulates millennial-scale AOA productivity. In particular, low lake levels under cold-dry climate conditions strengthen lake mixing and nutrient upwelling, promoting AOA productivity; in contrast, high lake levels during warm-humid climate conditions weaken upwelling, resulting in reduced AOA blooms. Changes in terrestrial nutrient availability also exert a secondary control on aquatic primary production and by extension, AOA productivity. We also show that anthropogenic human activities can potentially alter AOA productivity levels due to climate and land-use change.

Relationship between human activities and environmental changes in the southern Tibetan Plateau since the Little Ice Age

The Tibetan Plateau (TP) is one of the most challenging areas for human long-term settlement due to its extreme living environment. Understanding the relationship between human activities and environmental changes in this extreme environment is important and can provide a historical reference for adapting to future climate change. In this study, we took the Angren Basin in the southern TP as a case study to elucidate the relationship since Little Ice Age (LIA). Using fecal stanol in feces, lake and river surface sediments, surface soils, and sediment core, we found that specific indices S1 and S2 from the composition of coprostanol, epicoprostanol, 5β-ethylcoprostanol and 5β-ethylepicoprostanol can reflect changes in human population and herbivores, respectively. Through the comparison between environmental changes determined by grain size, elements, sedimentation rate, and other climate records, the relationship between human activities and environmental changes was interpreted. Our results indicate that: (i) during 1480–1820 CE, the fecal stanols in lake sediments mainly originated from livestock, and the human population was low. In contrast, during 1820–2021 CE, the proportion and flux of S1 have been continuously increasing, indicating significant population growth. (ii) During the middle LIA, the cold-dry climate inhibited the development of agriculture and farming. However, the increased precipitation during the late LIA promoted that development, resulting in an increase in human population and livestock in a short term. (iii) Since 1951, people have reclaimed wasteland and developed husbandry, leading to increased soil erosion. (iv) Over the past 40 years, with a warm-humid climate and good policy support, human activities, such as agriculture and husbandry, have rapidly increased, but soil erosion has declined in the recent 20 years due to good soil-water conservation efforts. This study sheds light on the relationship between human activities and environmental changes and provides insights into future climate change responses.

Impact of semi-private open spaces on outdoor thermal comfort in a residential neighbourhood in warm humid climate

ABSTRACT Semi-private open spaces are indispensable as they enhance society’s growth and contribute to individuals’ health and well-being, thereby improving the quality of life in residential neighbourhoods. However, at present, the integration of such open spaces into the planning of housing projects is often neglected and results in incidental open spaces in the built environment. These incidental open spaces, if designed and integrated carefully, can enhance thermal comfort and community activities significantly. Therefore, this study aims to assess the impact of semi-private open spaces on outdoor thermal comfort in a residential neighbourhood in Kochi, India. A low-rise residential neighbourhood was selected for the study, and the semi-private open spaces were categorized into six typologies based on location, shape, proportions, orientation, aspect ratio, sky view factor, and albedo. Further, the outdoor thermal comfort conditions of these typologies were assessed through simulations in Envi-Met software for a critical summer day. The comfort conditions were assessed through comfort indices namely physiological equivalent temperature and mean radiant temperature (MRT) and were compared to arrive at appropriate design recommendations for semi-private open spaces. The study found a significant correlation between orientation, aspect ratio, sky view factor, and shading with outdoor thermal comfort. The study found a sky view factor of 0.3–0.5, an aspect ratio greater than 1.5, orientation of open spaces in the N-S axis, and shading by trees with canopies above 2.5 m height as appropriate design strategies to reduce the heat stress in semi-private open spaces in low-rise residential neighbourhoods. The study recognizes the importance of integrating planned semi-private open spaces in the local building regulations which can improve the quality of open spaces and enhance public health and well-being while contributing to a better microclimate.

Geochemical and depositional environment of an Upper Cretaceous greensand giant (Münsterland Cretaceous Basin, Germany)

Based on integrated geochemical, mineralogical and stratigraphic-sedimentological analyses of core section KB 4507/1001 Essen-Bedingrade from the Münsterland Cretaceous Basin (northern Germany), the geochemical and depositional environment of a Late Cretaceous greensand giant has been elucidated. The >100-m-thick Cretaceous succession comprises the Essen Greensand (Cenomanian), Büren (lower Turonian), Duisburg (middle Turonian to lower Coniacian) and Emscher formations (middle to upper Coniacian), essentially consisting of alternating greensand and marl lithofacies. X-ray diffraction analyses showed that the abundant green grains undoubtedly constitute glauconitic minerals with high-order, 1M-type layer stacking. The depositional environment can be characterized as a shallow-marine setting in which nearshore greensands interfingered with mid-shelf marls. Inorganic geochemical analyses normalized to Al and compared to average shale (AS) show that most element/Al (E/Al) ratios are higher than AS values, including the chemical index of alteration (CIX). This suggest that an intensely chemically weathered wet hinterland provided for a constant supply of essential elements required for nearshore glaucony authigenesis under variably reducing or oxidizing conditions and slightly increased palaeoproductivity. The leaching of paleosols and swamp-like coastal wetlands during transgressive phases related to eustatic early Late Cretaceous sea-level changes was an important source for trace metals and nutrients while the considerable influx of terrestrial organic matter suggests a significant input of K related to plant decay. In a nutshell, our new integrated data from the Münsterland Cretaceous Basin provide important novel insights into the formative processes of authigenic glauconitic minerals during warm-humid climate phases of Earth history.

Biophysical landscapes of the Río La Virgen watershed in the Ocosingo municipality, Chiapas, Mexico

ABSTRACT The Río La Virgen watershed is located in the northwestern end of the municipality of Ocosingo, Chiapas, Mexico. This hydrographical unit is home to the city of Ocosingo. The objective of this research was to characterize the Biophysical landscapes that constitute the basin at the scale of 1:50 000. To achieve this goal, data on the biophysical components was compiled. This research defined five taxonomic typological levels: 3 classes, 10 subclasses, 22 localities, 52 land areas, and 213 sub-land areas. The main differentiating factors of the landscapes are the tectonics processes, which generate tectonic-karstic and tectonic-accumulative mountains; however, the inventory also reports landscapes of fluvio-torrential and fluvio-accumulative origin in temperate humid, semi-warm humid, and warm humid climates. The landscapes of tectonic-karstic and tectonic-accumulative origin cover over 85.42% of the surface area of the basin; by contrast, the Biophysical Landscapes of fluvial-accumulative and fluvial-torrential cover only 14.85%.

Calibration of simulation model to analyze hospital building energy performance

This research paper addresses the calibration of an energy simulation model for a naturally ventilated hospital building located in Mangalore, Karnataka, India, in a warm, humid climatic zone. The study aims to enhance the accuracy of energy consumption calculations through a calibration process by developing the energy model of a reference hospital building using EnergyPlus software. The required architectural design data, construction details, occupancy and schedule data and services are collected through documents, energy audits and documentation, measured drawings, and semi-structured interviews. Calibration parameters are systematically identified and adjusted through an iterative process. The monthly electricity bill is used to validate the simulation model. The simulation model reached during the validation process has an excellent Coefficient of Variation-Root Mean Squared Error of 4.24% and a Normalized Mean Bias Error of −4.42%, both of which meet the ASHRAE-approved accuracy standards. The paper also discusses the challenges and emphasizes the need for a nuanced approach to modeling healthcare facilities. Notwithstanding the challenges faced, the study offers insightful information about how to calibrate simulation models for hospital energy usage with the significant influence of scheduling for artificial lighting and equipment usage. By pioneering a manual calibration approach tailored to hospital simulation models in the warm humid climate of India, this paper offers a novel and practical solution to address the challenges of energy performance analysis in resource-constrained environments. The calibrated simulation model presented in this study is a valuable tool for assessing and improving the energy performance of naturally ventilated healthcare facilities. By creating alternative space layouts, the research findings aim to foster the development of hospital infrastructure that is both ecologically friendly and energy-efficient in a specific climatic context. This research is assured to make a substantial contribution to the advancement of sustainable hospital design in warm-humid climates, with implications for both academia and industry.

Influence of building orientation and thermal mass configuration on the prediction of Natural Ventilation Potential (NVP) of various climates of India.

Natural ventilation potential (NVP) of a climate is a theoretical basis, and it gains importance due to the promising need for building energy conservation while conceding required thermal comfort conditions. A modified NVP analytical model is proposed by considering parameters involved in the earlier models (Yang et al., Build Environ 40:738-746, 2005; Luo et al., Build Environ 42:2289-2298, 2007). The effect of the dynamic thermal behavior of the wall/roof and building orientation on the indoor air temperature has been evaluated. The analytical model is applied to 11 major cities of India that belong to composite, hot-dry, temperate, and warm-humid climates. Five different envelope configurations are analyzed to envisage the NVP of concern climate (ED-I to ED-V). The results show that the effect of dynamic thermal response factors on the NVP is significant, and optimization of thermal response factors in addition to the U-value is mandatory. The impact of wind frequency on the selection of building orientation is substantial since it influences the total heat gained by the building envelope. Moreover, it is perceived that the optimum building orientation is independent of the climate and weather conditions. ED-II and ED-III are energy-efficient envelopes for composite, temperate, warm-humid, and hot-dry climates. The results revealed that the Mumbai climate has the highest NVP of 66% while the building is oriented in an E-W direction, and the lowest is observed for Jodhpur, i.e., 44% of the year when the building is in the NE-SW direction. The model helps the building architectural designers envisage the true NVP and assess the suitability of the building for natural ventilation.

Genesis of gray sandstone within the red beds in HLJ-DL uranium deposit, southwest Songliao Basin and its relationship with uranium mineralization

The search for uranium deposits in the red beds is currently a hotspot in China's sandstone-type uranium exploration efforts. The typical occurrence of uranium deposits is within gray sandstone layers amidst the red beds, where the distribution of these gray sand bodies dictates the presence of uranium deposits. Hence, delving into the genesis of gray sandstone within the red beds proves beneficial for both uranium exploration and unraveling the ore-forming mechanisms. However, there is currently significant controversy surrounding the genesis of gray sandstone in the red beds. This paper focuses on the typical uranium deposit in the red beds—the HLJ-DL uranium deposit in the southwestern part of the Songliao Basin. It investigates the genesis of gray sandstone within uranium-bearing rock series and its relationship with uranium mineralization. The lithology of representative drill cores, including the red sandstone for comparative study, is methodically examined, along with their elemental geochemistry as well as carbon and oxygen isotope characteristics. The petrological characteristics suggest that both the gray and red sandstone share similar compositions of clastic particles, indicating minimal influence of the source rock on the sandstone color. The gray sandstone displays comparable TOC content (averaging around 0.05 %) and δ18OPDB values (averaging around −16 ‰) to the red sandstone. However, it exhibits relatively higher δ13CPDB values (averaging −0.26 ‰), whereas the average δ13CPDB value for the red beds is −1.61 ‰. The data indicate that the gray sandstone is less affected by hydrothermal or hydrocarbon fluids. Compared to the red sandstone, which has relatively higher Cu/Al values (averaging 1.09) and Fe3+/Fe2+ ratios (averaging 3.37), the gray sandstone exhibits low Cu/Al values (averaging 0.44) and a low Fe3+/Fe2+ ratio (averaging 0.36), suggesting its formation in a relatively reducing environment. The reducing conditions necessary for the formation of gray sandstone may stem from the climate becoming relatively warm and humid, irrespective of whether it originates from the original sedimentary environment or is induced by the reducing pore water discharged from dark mudstones. The chemical weathering index of fine-grained sediments indicates that, the gray sandstones were commonly configured in relatively humid-warm climate with fairly low dissolved oxygen content in the bottom water. Additionally, the deposition of the uranium-bearing rock series experienced alternating climatic changes, rather than consistently being in a humid-warm climate. This resulted in the sand bodies with low TOC content, insufficient reducing potential, and uranium mineralization primarily occurring in the interior of the basin. Organic matter has a relatively weak control over uranium mineralization, whereas uranium mineralization shows a certain correlation with iron reduction. The ore-forming fluid was uranium-rich oxygenated atmospheric water. Dark-colored mudstones, formed under humid-warm climatic condition, contain relatively high TOC contents (avg. 0.43 %) and exhibit a strong reducing capacity. The reducing pore water in dark-colored mudstones excreted into the adjacent sandstones under compaction during the early diagenesis, is able to serve as a vital reducing agent in later-stage uranium mineralization. Additionally, certain dark-colored mudstones with high uranium content (up to 944 ppm) undergo significant uranium pre-enrichment, providing a partial uranium source for uranium mineralization.

Hydrothermal and eco-environmental evolution on the southeastern Chinese Loess Plateau since the last deglaciation: evidence from terrestrial mollusk records

The ongoing global warming is altering hydrothermal patterns and eco-environments. However, it is unclear how they would respond under a natural warming scenario. Terrestrial mollusks in loess-paleosol sequences could serve as natural biological archives to explore this issue. In this study, terrestrial mollusk records from two loess-paleosol profiles on the southeastern Chinese Loess Plateau (CLP) were analyzed. Our results show that the cold-aridiphilous species decreased and the overall biodiversity increased gradually during the last deglaciation (∼19.0–11.5 ka BP), which was accompanied with the shift from cold-dry to warm-humid climate. Moreover, the mollusk communities reacted to Heinrich event 1 (H1) cooling. In the early-middle Holocene (∼11.5–5.5 ka BP), mollusk communities were dominated by the thermo-humidiphilous species, characterized by stable community composition, increased species richness and evenness with warm-humid climate. Thereafter, there was a noticeable decrease in species diversity and increase in the cold-aridiphilous species in the mid-late Holocene (∼5.5–0 ka BP), associated with a gradual shift towards a cold-dry climate. On the whole, it is noteworthy that the count of thermo-humidiphilous species increased remarkably at ∼16 ka BP, which is synchronous with a significant increase in the Northern Hemisphere summer insolation. Interestingly, this change of terrestrial mollusks preceded the formation of the Holocene paleosol at ∼8 ka as indicated by the pronounced increase in magnetic susceptibility and decrease of mean grain size. This suggests that the substantial East Asian summer monsoon (EASM) precipitation lagged the onset of deglacial warming on the southeastern CLP. Furthermore, this delay may be attributed to the negative feedback of North Atlantic meltwater, which caused a decline in the intensity of Atlantic Meridional Overturning Circulation (AMOC) and inhibited the rapid enhancement of EASM precipitation during the last deglaciation. Altogether, this provides crucial geological background evidence for exploring the potential regional hydrothermal and biodiversity responses to global warming in the near future.

Geochemical constraints on the Gano karst bauxite deposit, eastern Alborz Mountains, northern Iran: Implications for provenance, elemental mobility, and distribution of critical metals

The Gano karst bauxite deposit is located in the eastern Alborz Mountains, 90 km NE of Semnan city, northern Iran. The layers and lenticular patches of bauxite are hosted in the Triassic karstified carbonate rocks interbedded with calcareous shale of the Elika Formation, unconformably overlain by siliciclastics of the early Jurassic Shemshak Formation. The bauxite ores have a mineral assemblage dominated by diaspore and hematite, with lesser kaolinite, illite, chlorite, goethite, anatase, dolomite, and quartz. In the Gano area, intrusions range from monzonite to quartz monzonite in composition with an alkaline composition that generated in an extensional regime within a plate tectonic setting. Geochemical signatures of the Gano bauxite ores suggest a derivation from the monzonite intrusions at the base of the Elika Formation, although a contribution of interbedded calcareous shale of the Elika Formation cannot be excluded. Based on the variation of Ce anomaly across the studied profile and the integration of petrographic evidence and mineralogical and geochemical data, the Gano deposit formed in an oxidized environment under warm-humid climates, significantly linked to rainfall seasonality and groundwater-level fluctuations. Gallium, Nb, and V median values of the Gano bauxite ores are a bit above the maximum value of these critical metals in the northwestern Iranian and Alborz bauxite data set, making diaspore-, anatase-, and hematite-rich layers and lenses valuable for further exploration of these critical metals.

Tree species with potential for reforestation in coastal zones of the humid tropics

Aim of study: The native species of warm humid climates Ceiba pentandra, Tabebuia rosea, Gliricidia sepium, Enterolobium cyclocarpum and Brosimum alicastrum are often included in Mexican reforestation programs. We evaluated the growth response in sandy soils of these species that could serve as pioneers in the restoration of coastal areas. Area of study: Alluvial plain in Frontera, Tabasco, Mexico. Material and methods: A total of 1080 plants were planted in 2014 and evaluated for 23 months in 30 plots under a randomized block design with six replications. The sample plots each occupied 36 m2 (each with 16 plants). Survival percentage, stem height (SH), basal diameter (BD) and basal area (BA) were quantified. Survival and growth variables were analyzed using logistic regression and ANOVA for repeated measures, respectively. Main results: At the end of the experiment (2016), high survival was demonstrated in G. sepium (88 %) and in C. pentandra (86 %), while B. alicastrum presented total mortality at six months. The highest values of SH and BD were presented in C. pentandra (2.9 m and 7.8 cm, respectively) and in G. sepium (2.6 m and 4.2 cm, respectively). Gliricidia sepium differed significantly from C. pentandra in terms of BA (5.9 vs. 23 m2 ha-1, respectively). Research highlights: The native species C. pentandra and G. sepium presented high survival and growth in the sandy soils; G. sepium showed strong adaptation to the environment and C. pentandra offered suitable coverage, characteristics that are necessary for the success of reforestation and restoration programs.

Strength Characteristics of Carbon Fiber Reinforced Plastic in Shear and Cyclic Extension-Compression after 7 Years of Climate Exposure

The results of studies of carbon fiber reinforced plastic (CFRP) for aviation purposes based on the Cycom 977-2 epoxy binder and Tenax® IMS carbon fibers after 7 years of exposure under a canopy and on an open atmospheric stand in the warm humid climate of Sochi are presented. The influence of climatic aging is determined by the change in strength parameters during interlaminar shear and cyclic tension – compression. After exposure under a canopy, the strength characteristics during interlaminar shear and cyclic tension–compression increase by 7–13 %. If the plate is under the direct influence of solar radiation, then the strength characteristics of the material are slightly reduced, but remain at the level of the original values. The kinetic concept of fracture was used to interpret the results. The thermal activation analysis showed that the characteristics of the inelasticity of the plate specimens, both in terms of the relaxation and hysteresis parts of energy absorption, correspond to their strength characteristics.

Weathering Intensity, Paleoclimatic, and Progressive Expansion of Bottom-Water Anoxia in the Middle Jurassic Khatatba Formation, Southern Tethys: Geochemical Perspectives

The Jurassic Period was a significant phase of variable organic matter accumulation in paleo-shelf areas of the southern Tethys (Egypt). Reconstructing the paleoredox conditions, paleoclimate, and weathering intensity, along with the role of terrigenous sediment flux and mineralogical maturity, is important for understanding basin infill history and prevalent paleoenvironmental conditions. Here, inorganic geochemical data are presented from the Middle Jurassic Khatatba Formation and two samples from the underlying Ras Qattara and the overlying Masajid formations in the Jana-1x well, Shushan Basin, Western Desert. Twenty-four (24) whole-rock samples were analyzed for their major and trace element composition and carbonate content. The Khatatba Formation represents one of the major hydrocarbon source rocks in the North Western Desert, Egypt. Redox conditions were assessed based on enrichment factors of redox-sensitive elements Mo, V, U, and Co. Results revealed that the Khatatba Formation was deposited under predominant anoxic bottom and pore water conditions, in contrast to the oxic settings that were prevalent during the deposition of the Ras Qattara and Masajid formations. Continental weathering intensity and paleoclimate were reconstructed based on several proxies, such as the chemical index of alteration (CIA), K2O/Rb, Rb/Sr, Ln(Al2O3/Na2O), and Al/K ratios, indicating that the studied succession was deposited during alternating phases between weak and moderate weathering intensity under arid and warm-humid climates, respectively. Periods of enhanced continental weathering were associated with high values of clastic ratios such as Si/Al, Ti/Al, and Zr/Al, suggesting increased terrigenous sediment supply during intensified hydrological cycling. These ratios further provided inferences about the changes in sediment grain size, such as a change from shale to coarse silt- and sand-size fractions.

High-resolution climate change during the Marine Isotope Stage 3 revealed by Zhouqu loess in the eastern margin of the Tibetan Plateau

A consensus has not yet been reached on effects of climate change and driving mechanisms between the Tibetan Plateau (TP) and adjacent monsoonal areas during the Marine Isotope Stage 3 (MIS 3). Loess–paleosol sequences from the TP provide valuable information about the MIS 3 environmental history. Detailed color index and a diffuse reflectance spectral (DRS) analysis of Zhouqu (ZQ) loess from the Western Qinling Mountains were conducted to investigate climate change on the eastern margin of the TP during the MIS 3. Our results show that the variations in color index and iron oxide content in ZQ loess are mainly caused by the pedogenesis and climate conditions. The lightness (L*) value and hematite (Hm) content were used to reconstruct the precipitation history and temperature changes, respectively. The reconstructed records revealed that climate change during the MIS 3 was characterized by high frequency and large amplitude, with millennial-scale changes superimposed on orbital-scale changes. Warm–humid climate occurred in the late MIS 3, while the early climate of MIS 3 was relatively cold–dry. The Indian summer monsoon (ISM) and temperature variations during the MIS 3 mainly occurred due to obliquity and precession. The North Atlantic cooling led to the southward movement of the Intertropical Convergence Zone, and the downstream cooling of the atmosphere by the westerly jet could result in events on a millennial-scale in the eastern margin of the TP. The interhemispheric forcing may play an important role in driving the strong summer monsoon in the late MIS 3.