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The variability and dynamics of the Asian monsoon (AM, hereafter indicates both of the summer and winter monsoons.) at orbital and millennial timescales has attracted wide interest. Chinese loess deposits, covering an area of ~500 × 103 km2 and with a thickness of several tens to more than three hundred meters, is an ideal continental archive to reconstruct AM variations during the Quaternary epoch. Over the past thirty years, since the earliest paper published in an international journal that linked the Asian monsoon and Chinese loess deposits, many studies have been undertaken focusing on this research topic. These results have greatly deepened our understanding of the variations of the AM climate and their driving mechanisms during the past ~2.6 Myr. In this paper, we emphasize recent progress on the AM variability and dynamics revealed by Chinese loess records; in particular, we discuss the reliability and precision of the timescale and the monsoon proxy indicators for the loess-paleosol sequences, which are two fundamental aspects for understanding AM behavior. We analyze what we know and discuss what we do not know about the AM. We refine the timescale for the typical loess-paleosol sequence in the central Chinese Loess Plateau (CLP), which can be used as a new timescale to study palaeoclimate and palaeoenvironmental changes in the monsoonal Asia. We conclude that low-latitude insolation changes induced by precession, and global ice volume, temperature at high-latitudes, as well as sea-level changes forced variations of the AM at orbital time scales. High-latitude cooling events and low-latitude hydroclimate process at millennial time scales, such as climate changes associated with Heinrich events and Dansgaard-Oeschger cycles in Northern Atlantic and Greenland, have also modulated AM variability. We suggest that high-latitude forcing of AM variations occurs through ocean and atmospheric circulation linkages, although the roles of atmospheric CO 2 , ocean and vegetation feedbacks need further investigation. In future study, high-resolution independent dating, novel proxy indices and transient numerical simulations are still basic tools to understand the loess deposition and AM variations that require considerably more work. Issues such as reliable spatial comparison and regional linkages of records (dependent on precise and accurate numerical chronologies), and quantitative reconstruction of the AM variations, should be given priority in the study the past climate change in Asia, and low-latitude hydroclimate process. [ABSTRACT FROM AUTHOR]

The high mountain regions of Asia contain more glacial ice than anywhere on the planet outside of the polar regions. Because of the large population living in the Indus watershed region who are reliant on melt from these glaciers for fresh water, understanding the factors that affect glacial melt along with the impacts of climate change on the region is important for managing these natural resources. While there are multiple climate data products (e.g., reanalysis and global climate models) available to study the impact of climate change on this region, each product will have a different amount of skill in projecting a given climate variable, such as precipitation. In this research, we develop a spatially varying mixture model to compare the distribution of precipitation in the High Mountain Asia region as produced by climate models with the corresponding distribution from in situ observations from the Asian Precipitation—Highly Resolved Observational Data Integration Towards Evaluation (APHRODITE) data product. Parameter estimation is carried out via a computationally efficient Markov chain Monte Carlo algorithm. Each of the estimated climate distributions from each climate data product is then validated against APHRODITE using a spatially varying Kullback–Leibler divergence measure. Supplementary materials accompanying this paper appear online. [ABSTRACT FROM AUTHOR]

Extreme climate events are hotspots in global change. However, research on the changes in future compound events and population exposure is still limited. Leveraging from the data of the sixth phase of the Coupled Model Intercomparison Project (CMIP6), this paper aims to analyze the temporal and spatial changes of global compound temperature and precipitation extreme events in the future. We also predict the risk of population exposure and quantify the contribution of different factors to exposure. The results show that: (1) In the next 80 years, compound hot-dry event (CHDE) will increase at a rate of 0.02, 0.03, and 0.08 days per decade under the three scenarios of SSP1–2.6, SSP2–4.5 and SSP5–8.5, respectively. By comparison, compound hot-humidity event (CHHE) shows a downward trend under the three scenarios, with a downward rate of 0.01, 0.02, and 0.11 days per decade, respectively. (2) Under the SSP1–2.6 and SSP2–4.5 scenarios, CHDE and CHHE have two or more mutation points. Under the SSP5–8.5 scenario, CHDE shows a significant upward and CHHE shows a significant downward trend in the middle and late 21st century. These two indices exhibit periodic changes in all three scenarios (3) South Asia, West Asia, and Northeast Africa have higher CHDE values, while regions with higher CHHE values are located in North Asia and Greenland. (4) Climate change is a major factor affecting population exposure. For CHDE, climate, population, and their synergistic effects contribute about 75%, 20%, and 5% to the exposure, respectively. For CHHE, the contributions of these three factors are 85%, 10%, and 5% respectively. These findings provide scientific guidance for the rational formulation of population policies, the effective avoidance of climate disaster risks and the protection of human health. • Frequency of hot-dry events and hot-humidity events will increase and decrease, respectively, in the future. • There are abrupt points and periodicity in the future time series of compound temperature and precipitation extremes. • Asia is projected to have the greatest exposure and climate change contributes the most to exposure. [ABSTRACT FROM AUTHOR]

The evolution of global temperature during Holocene is crucial for understanding the mechanisms of climate change and future climate trends. However, there is a discrepancy between the temperature trends reconstructed from proxy and model, which is attributed to the seasonal biases and the appearance of the Holocene thermal maximum was dominated by the temperature of the warm season. In this paper, fossil charcoal assemblages from the southern Chinese Loess Plateau were analysed to provide quantitative mean annual temperatures (MAT) and four-season temperature records during 6.55–3.45 cal ka BP. The results indicate that both the seasonal temperatures and MAT during the middle Holocene reached warm peaks between 5.55 and 5.35 cal ka BP. The similar trend between the winter temperature (WIT) and MAT denotes the highest contribution of WIT changes to the MAT in the study area since the mid-Holocene. • Flowering functional group was used to reconstruct spring-autumn temperature. • Nonhardy plants were used to reconstruct winter temperature. • Winter temperature contributed the most to the annual temperature since mid-Holocene. • Middle-Holocene temperature was not showing a long-term warming trend. [ABSTRACT FROM AUTHOR]

Soil erosion is part of the erosion-sedimentation cycle and a type of land degradation that can be caused by poor land management. This is expected to be exacerbated by climate change. The rainfall erosivity factor (R) of the Universal Soil Loss Equation (USLE) family of soil erosion models is one of the most important parameters being studied because it is heavily influenced by climate change. The determination of the R factor necessitates high-frequency precipitation data, which are unavailable for a significant portion of the globe. For decades, researchers in data-sparse regions have estimated the R factor using empirical equations that required only monthly or annual rainfall data. Unfortunately, many of these equations are outdated and susceptible to misuse. This study presents an empirical R equation based on the Modified Fournier Index (MFI) that has caused probably one of the most widespread and unnoticed errors in soil erosion research for at least 33 years. Our exhaustive literature search and analysis uncovered 125 papers with 28 incorrect R equation formulations. We discovered that the earliest incorrect publication dates back to 1989, and most of the studies were conducted in Asia (China and India). The 125 published papers have similar citation characteristics (three citations per year per paper) as other papers in the field of soil erosion modelling, and many of the 125 papers were published in well-known scientific journals. Together, they have been cited over 3300 times by international researchers. In addition, the number of incorrect papers has increased dramatically over the past few years (2015–2021), indicating that the equation is spreading more frequently than the general publication trend. Since using an incorrect R equation can result in a significant bias in estimating the R factor and, consequently, soil erosion, the incorrect use could significantly bias numerous studies. The inaccuracy also hinders global efforts like the "Global Applications of Soil Erosion Modelling Tracker (GASEMT)" to synthesize soil erosion studies worldwide to shed light on the global problem of soil erosion and to promote environmental education. Consequently, the primary objective of this paper is to contribute to the recognition of the use of incorrect R equations, thereby reducing or even preventing their further spread and thus limiting the number of studies publishing biased results. [ABSTRACT FROM AUTHOR]

Ancient irrigation systems (AISs) have been providing a multitude of ecosystem services to rural farming and urban communities in Asia and Africa, especially in arid and semi-arid climatic areas with low rainfall. Many AISs, however have now been degraded. A systematic analysis of AISs on their typologies, causes of degradation, and their ecosystem services is lacking. The objective of this review was to synthesize the knowledge on AISs on their typologies, status and causes of degradation, ecosystem services and functions, and identify gaps in research in Asia and Africa. A critical review of peer-reviewed journal papers, conference and workshop proceedings, book chapters, grey literature, and country reports was conducted. Qualitative and quantitative information from journal papers were used to conceptualize the typologies and analyze the status and causes of degradation, and ecosystems services and functions provided by the AISs. Based on the review, we classified AISs into three groups by source of irrigation water: Rainwater harvesting system (RHS) with small reservoirs, ground water based system, and floodwater based system. The RHSs, which used to receive reliable rainfall and managed by well cohesive social organizations for their maintenance and functioning in past, have now been silting due to extreme rainfall pattern and breakdown of the cohesive organizations in recent decades. In ground water based systems, indiscriminate development of deep tube wells causing siltation of channels has been a major challenge. In floodwater irrigation systems, irregular rainfall in the highlands and the breakage of irrigation structures by destructive floods were the main causes of degradation. Lack of maintenance and increased soil erosion, inadequate skilled manpower, and declining support from the government for repair and maintenance were the main causes of degradation of all AISs. The main ecosystem service provided by all AISs is water for agriculture. In tank- and pond-based systems, fish farming is also practiced. Tank irrigation systems provide various types of provisioning, regulatory, cultural and supporting services, especially in India and Sri Lanka. Ground water based systems provide water for domestic purposes and various cultural services. Floodwater based systems provide water for power generation and wildlife habitat maintenance and help in flood control. The knowledge generated through the review provide evidence-based information, and help aware governments, private sectors and development agencies for improved policy planning and decision making, and prioritizing the restoration, rehabilitation, and management of various AISs. Community Managed Ancient Irrigation Systems in Asia and Africa: Typologies, Degradation and Ecosystem services. [Display omitted] • Ancient irrigation systems (AISs) in Asia and Africa provide a multitude of benefits to mankind but are at a threat of degradation. • A systematic review conducted to identify typologies, status and causes of degradation of, and ecosystems services provided by, AISs. • Three typologies (rainwater harvesting, groundwater, and surface water based) and four ecosystems services identified. • Cascade tanks in Sri Lanka and India provide irrigation water for farming communities and ecosystem services for local communities and societies. • Rehabilitation of AISs needs urgent attention by governments, private sector, and development partners. [ABSTRACT FROM AUTHOR]

In the face of climate change, it is essential to rethink how we build to reduce the environmental impact of the construction industry. Timber construction can be a solution to reduce the use of concrete or steel, whose manufacture emits much CO 2. This paper proposes a method to reinterpret tenon and mortise joints for construction. Friction-based assemblies, particularly mortise and tenon wooden joints, have been studied for centuries in Asia and Europe and may offer promising constructive solutions, such as allowing disassembling rather than demolishing a structure. These assemblies can be complex; they initially required a great deal of craftsmanship, which robotics can now replace to manufacture and assemble them. Nevertheless, it is necessary to develop methods to produce these robotic joints. Our method uses non-sequential assemblies, which are by definition, opposed to sequential assemblies. An assembly is said to be sequential when the elements that compose it are assembled one after the other, in a defined order or not. For a non-sequential assembly, all the elements that compose it are in motion and assembled simultaneously. This assembly method has the particularity of being locked only by its kinematics, which makes it possible to easily (dis)assemble the elements by only knowing their motion. After an introduction and defining the terms and hypotheses of our research, we discuss the related word. In the fourth section, the developed method is explained. Then, we introduce the different parameters to control the assembly's design and kinematics. After that, we extend the previous method to the third dimension. Finally, a construction prototype demonstrates the method's efficiency. [Display omitted] • Generality: our method works for pure translation, in 2D or 3D. • Exhaustivity: any kinematic can be generate thanks to parallel transformation. • Control: calculations and parameters are given to choose the kinematics according to external factors. [ABSTRACT FROM AUTHOR]

Marine Isotope Stage (MIS) 3 is the latest interstadial to be a significant period for paleoclimate research. The mild interstadial climate in MIS 3 can shed light on studies of the current warming period. However, it is uncertain whether or not the humidity in MIS 3 exceeds that in Holocene level, and forcing mechanisms of paleoclimate evolution remains controversial. In this paper, we use pollen and AMS 14C dating data of a sediment core Ailike-2019 (4.49 m) recovered from Lake Ailike, Xinjiang in arid central Asia, to reconstruct the vegetation and climate changes in Lake Ailike over the last 40,000 years. The results show that Lake Ailike region has been dominated by desert vegetation since the middle MIS 3. The vegetation coverage shows that climate was arid in the middle MIS 3 (40.2-33.2 cal kyr BP), ameliorated during the late MIS 3 (33.2-26.7 cal kyr BP) but still dry, extremely dry during MIS 2 (26.7-12 cal kyr BP), and relatively wet during Holocene (12-0 cal kyr BP). The climate in the Holocene was wetter than in the mid-late MIS 3 in Lake Ailike, which is generally consistent with the paleoclimate records from arid central Asia and Europe. This climate pattern might be attributed to amounts of vapor transported by the westerlies and Siberian high pressure. Low/high Northern Atlantic sea-surface temperatures (SSTs) induced by decreased/increased Northern Hemisphere summer insolation resulted in westerlies transporting less/more amount of vapor to the arid central Asia during MIS 3/Holocene. Meanwhile, intensified/weakened Siberian high pressure resulting from the expanding/melting of ice sheet might induce dry/wet climate conditions in the mid-late MIS 3/the Holocene. • Fossil pollen records from Lake Ailike reveal vegetation and climate history since the middle MIS 3. • The climate was significantly wetter in the Holocene than in the mid-late MIS 3 in Lake Ailike. • This climate pattern is in general agreement with that in arid central Asia and Europe. • Eurasian ice volume and Northern Atlantic SSTs might be the driving factors of effective moisture in arid central Asia. [ABSTRACT FROM AUTHOR]