How Water-Development Nexus Can Reunite Central Asia?

The following article has been retracted due to the fact that it cannot be accepted by the author’s university as a scientific peer-reviewed publication. The Editorial Board takes a very strong respect to the author’s situation on this matter. This paper published in World Journal of Engineering and Technology Vol.2 No.3B, September 2014, has been removed from this site.

Climate change, water resources and sustainable development in the arid and semi-arid lands of Central Asia in the past 30 years

The countries of Central Asia are collectively known as the five "-stans": Uzbekistan, Kyrgyzstan, Turkmenistan, Tajikistan and Kazakhstan. In recent times, the Central Asian region has been affected by the shrinkage of the Aral Sea, widespread desertification, soil salinization, biodiversity loss, frequent sand storms, and many other ecological disasters. This paper is a review article based upon the collection, identification and collation of previous studies of environmental changes and regional developments in Central Asia in the past 30 years. Most recent studies have reached a consensus that the temperature rise in Central Asia is occurring faster than the global average. This warming trend will not only result in a higher evaporation in the basin oases, but also to a significant retreat of glaciers in the mountainous areas. Water is the key to sustainable development in the arid and semi-arid regions in Central Asia. The uneven distribution, over consumption, and pollution of water resources in Central Asia have caused severe water supply problems, which have been affecting regional harmony and development for the past 30 years. The widespread and significant land use changes in the 1990 s could be used to improve our understanding of natural variability and human interaction in the region. There has been a positive trend of trans-border cooperation among the Central Asian countries in recent years. International attention has grown and research projects have been initiated to provide water and ecosystem protection in Central Asia. However, the agreements that have been reached might not be able to deliver practical action in time to prevent severe ecological disasters. Water management should be based on hydrographic borders and ministries should be able to make timely decisions without political intervention. Fully integrated management of water resources, land use and industrial development is essential in Central Asia. The ecological crisis should provide sufficient motivation to reach a consensus on unified water management throughout the region.

Characteristics of Central Southwest Asian Water Budgets and Their Impacts on Regional Climate

Water budgets terms, evapotranspiration (E), precipitation (P), runoff (N), moisture convergence (MC) and both surface as well as atmospheric residual terms have been computed with National Centers for Environmental Prediction (NCEP) (1948-2007) and European Centre for Medium-Range Weather Forecasts (ECMWF) ERA-40 (1958-2001) reanalysis data sets for Central Southwest Asia (CSWA).The domain of the study is 45° - 75°E & 25° - 40°N. Only the land area has been used in these calculations. It is noted in the comparison of both reanalysis data sets with Global Precipitation Climatology Centre (GPCC) that all three data sets record different precipitation before 1970. The maximum is from NCEP and the minimum with ERA-40. However, after 1970 all the data sets record almost the same precipitation. ERA-40 computes two phases of MC. Before 1975, the domain acts as a moisture source, whereas after 1975 it behaves as a moisture sink. The region CSWA is divided into six sub areas with rotational principle factor analysis and we distinguish them by different approached weather systems acting on each area. Finally, NCEP yearly precipitation is further divided into seasons;winter (November to April) and summer (May to October) and two phases have been noted. The variation in winter precipitation is more than summer during last 60-year analysis.

Food security amid the COVID-19 pandemic in Central Asia:Evidence from rural Tajikistan

Food security has been long understudied in the context of Central Asia.We present an analysis examining household-level food demand for Tajikistan and assessing the magnitude of its food security changes during the COVID-19 pandemic.Based on an extensive household survey data set from Tajikistan,we estimate the expenditure,income,and price elasticities for nine food categories using the QUAIDS model.Then,we develop a microsimulation model using the estimated elasticities to assess the dual impact of declining remittance income and rising food prices stemming from the pandemic shock.There are significant differences in demand elasticities across food groups,with high elasticities observed for nutritious foods,such as meat,fruit,eggs,and milk,in rural households.Moreover,our findings show that changes in remittance income and food prices significantly negatively affected food security for rural households during the COVID-19 pandemic.These findings have important implications for policymakers concerned about rural livelihoods and food security in remittance-receiving economies during the post-pandemic period.

Low-carbon economic development in Central Asia based on LMDI decomposition and comparative decoupling analyses

Low-carbon economic development is a strategy that is emerging in response to global climate change. Being the third-largest energy base in the world, Central Asia should adopt rational and efficient energy utilization to achieve the sustainable economic development. In this study, the logarithmic mean Divisia index(LMDI) decomposition method was used to explore the influence factors of CO2 emissions in Central Asia(including Kazakhstan, Uzbekistan, Kyrgyzstan, Tajikistan and Turkmenistan) during the period 1992–2014. Moreover, decoupling elasticity and decoupling index based on the LMDI decomposition results were employed to explore the relationship between economic growth and CO2 emissions during the study period. Our results show that the total CO2 emissions decreased during the period 1992–1998, influenced by the collapse of the Soviet Union in 1991 and the subsequent financial crisis. After 1998, the total CO2 emissions started to increase slowly along with the economic growth after the market economic reform. Energy-related CO2 emissions increased in Central Asia, mainly driven by economic activity effect and population effect, while energy intensity effect and energy carbon structure effect were the primary factors inhibiting CO2 emissions. The contribution percentages of these four factors(economic activity effect, population effect, energy intensity effect and energy carbon structure effect) to the total CO2 emissions were 11.80%, 39.08%, –44.82% and –4.32%, respectively, during the study period. Kazakhstan, Uzbekistan and Turkmenistan released great quantities of CO2 with the annual average emissions of 189.69×106, 45.55×106 and 115.38×106 t, respectively. In fact, their economic developments depended on high-carbon energies. The decoupling indices clarified the relationship between CO2 emissions and economic growth, highlighting the occurrence of a ’’weak decoupling’’ between these two variables in Central Asia. In conclusion, our results indicate that CO2 emissions are still not completely decoupled from economic growth in Central Asia. Based on these results, we suggest four key policy suggestions in this paper to help Central Asia to reduce CO2 emissions and build a resource-conserving and environment-friendly society.

An Inquiry into the Approach to Asian Regional Trade Integration Under the Belt and Road Initiative——The Case of the Alignment of a China-Japan-South Korea Free Trade Area

It has been five years since the Belt and Road Initiative (BRI) was first introduced. Though there has been a growing body of literature on regional cooperation between covered countries, Japan and South Korea have been barely discussed. This paper starts with the consensus-based mechanism of a China-Japan-South Korea Free Trade Area (FTA) to probe the approach of its alignment with the BRI in terms of the sequence of “master plans,”“viability of cooperation,” and “embedding of rules.” This inquiry found that the three countries have a shared interest in cooperation in Central Asia to which China prefers a pragmatic approach, while Japan and South Korea an approach combining idealism with pragmatism. Given the huge potential of cooperation between the trio, it is suggested that a “Central Asia chapter” be incorporated in the negotiation framework of this trilateral FTA, and that the design feature three aspects;fundamental principles, specific rules, and an executive body with a view to functionally contributing to regional trade integration in Asia. This approach may also be applied to the alignment of other Asian areas with the BRI.

The Central Asian Regional Security Complex Revisited:Understanding the Implications of the US Retreat From Afghanistan

On February 29,2020,President Donald Trump announced the United States signed a peace agreement with the Taliban,signifying the United States‟intention of leaving Afghanistan in the near future.Though the global pandemic has altered US withdrawal plans,the question still remains:What will become of the Central Asian regional security complex following America‟s exit?Buffered by the presence of the United States since 2001,the Central Asian republics now once again find themselves at a crossroads to either rely on individual defense services or to develop increased military cooperation with interested states.Recognizing Central Asia‟s history of collaboration among its regional and near-regional countries,I argue that the Central Asian Republics of Afghanistan,Kazakhstan,Kyrgyzstan,Tajikistan,Turkmenistan,and Uzbekistan will seek to develop stronger security ties with neighboring regional security complexes(RSCs),namely the South Asian,Russian,and Chinese RSCs.With decreased American influence,each of the states in these RSCs is rushing to fill the void of influence in order to capitalize on Central Asia‟s geostrategic position in Eurasia as well as secure itself from the threat of non-state actors still prevalent in the region.I further argue that the states in the Central Asian RSC additionally seek these same benefits and security,but receive them to a much lesser extent than their more powerful regional neighbors.Understanding how the American withdrawal from Afghanistan will impact Central Asian RSC relations can provide insight into how great power vacuums are filled both by great powers and regional powers alike.

Potential distribution of Haloxylon ammodendron in Central Asia under climate change

Understanding the spatial distribution of plant species and their dynamic changes in arid areas is crucial for addressing the challenges posed by climate change.Haloxylon ammodendron shelterbelts are essential for the protection of plant resources and the control of desertification in Central Asia.Thus far,the potential suitable habitats of H.ammodendron in Central Asia are still uncertain in the future under global climate change conditions.This study utilised the maximum entropy(MaxEnt)model to combine the current distribution data of H.ammodendron with its growth-related data to analyze the potential distribution pattern of H.ammodendron across Central Asia.The results show that there are suitable habitats of H.ammodendron in the Aralkum Desert,northern slopes of the Tianshan Mountains,and the upstream of the Tarim River and western edge of the Taklimakan Desert in the Tarim Basin under the current climate conditions.The period from 2021 to 2040 is projected to undergo significant changes in the suitable habitat area of H.ammodendron in Central Asia,with a projected 15.0% decrease in the unsuitable habitat area.Inland areas farther from the ocean,such as the Caspian Sea and Aralkum Desert,will continue to experience a decrease in the suitable habitats of H.ammodendron.Regions exhibiting frequent fluctuations in the habitat suitability levels are primarily found along the axis stretching from Astana to Kazakhskiy Melkosopochnik in Kazakhstan.These regions can transition into suitable habitats under varying climate conditions,requiring the implementation of appropriate human intervention measures to prevent desertification.Future climate conditions are expected to cause an eastward shift in the geometric centre of the potential suitable habitats of H.ammodendron,with the extent of this shift amplifying alongside more greenhouse gas emissions.This study can provide theoretical support for the spatial configuration of H.ammodendron shelterbelts and desertification control in Central Asia,emphasising the importance of proactive measures to adapt to climate change in the future.

LARGEST ALTYN TAGH LITHOSPHERIC SHEAR FAULT IN CENTRAL ASIA

The Altyn Tagh fault (ATF) extending in NEE—SWW direction lying at the northwestern boundary of Qinghai—Tibet plateau is the largest strike\|slip fault in Central Asia. On the basis of recent geologic mapping and detailed study of lithotectonic characteristics for the paleotectonic units at the two sides of the Altyn Tagh Fault ( Altun Mt. to west and the Qilian Mt. to east ) we propose that the paleotectonic units in the Altun Mt. can be correlated with those in the Qilian Mt. assuming 400km left\|lateral displacement for the Altyn Tagh fault. Natural seismic data across the Altun Mt. indicate that the Altyn Tagh fault is a lithospheric shear fault and the lithospheric shearing is probably related to southward intracontinental oblique subduction of the Tarim terrane beneath the Altun Mt.1\ Comparison of the major paleotectonic units at the two sides of the Altyn Tagh fault\;(1) The Alxa\|Dunhuang Massif:The Alxa massif lying at the southern margin of the Sino\|Korean craton consists mainly of an Early Proterozoic basement including high\|grade and middle\|grade metamorphic rocks, which were intruded by granite at 1719Ma. The Paleozoic passive margin sediments is well developed. In the Altun Mt., the Early Proterozoic and late Archean basement of the Duhuang massif includes high\|grade and middle\|grade metamorphic rocks dating 2789Ma (Sm\|Nd method) and 2405Ma (U\|Pb method).

Population genetic insights into the conservation of common walnut(Juglans regia)in Central Asia

The common walnut(Juglans regia)is one of the most economically important nut trees cultivated worldwide.Despite its importance,no comprehensive evaluation of walnut tree population genetics has been undertaken across the range where it originated,Central Asia.In this study,we investigated the genetic diversity and population structure of 1082 individuals from 46 populations across Central Asia.We found moderate genetic diversity of J.regia across Central Asia,with 46 populations clustered into three groups with a weak relationship between genetic and geographic distance.Our findings reveal that the western Himalaya might be the core region of common walnut genetic diversity in Central Asia and that,except for two populations in Gongliu Wild Walnut Valley,humans might have introduced walnut populations to Xinjiang,China.The observed distribution of the genetic landscape has probably been affected by historical climate fluctuation,breeding system,and prolonged anthropogenic activity.We propose the conservation of the core genetic diversity resources in the western Himalaya and pay special attention to populations from Gongliu in Xinjiang.These findings enhance our understanding of the genetic variation throughout the distribution range of J.regia in Central Asia,which will provide a key prerequisite for evidence-based conservation and management.

Oil and gas cooperation between China and Central Asia in an environment of political and resource competition

This paper investigates Central Asia＇s oil and gas resources, special geopolitics and energy competition, and approaches, challenges and prospects in cooperation between China and Central Asia. The objective is to propose measures for oil and gas cooperation between China and Central Asia. Central Asia is rich in oil and gas resources. Its remaining recoverable reserves of crude oil and natural gas account for 1.9% and 10.6 %, respectively, of the world＇s total reserves. Moreover, there is great exploration and development potential. As a strategic channel connecting Eurasia, Central Asia has a prominent geopolitical status. Many powerful countries such as the United States, Russia and China, as well as Europe, have an intense energy competition in Central Asia. In the oil and gas cooperation with Central Asia, the China National Petroleum Corporation （CNPC） focuses on establishing a coordination group, promoting overall oil and gas business opportunities and sustainable development, innovating and applying specialty engineering technology and improving project economic benefits. Through its efforts over the last nearly two decades, the China National Petroleum Corporation has completed a 50-million-tonne a year oil and gas production centre in Central Asia and oil and gas pipelines passing through multiple countries, becoming an important channel for securing China＇s energy imports. If appropriate measures are taken in the ＇Thirteenth Five-Year Plan＇ period or later, the China National Petroleum Corporation will develop a 100-million-tonne p.a. oil and gas production centre in Central Asia and a strategic oil and gas import channel exceeding this amount of production. This cooperation between China and Central Asia is however faced with the following challenges： increasing multinational competition uncertainty, potential risks in the political systems of Central Asian countries, frequently occurring violence and also resource policy tightening in Central Asia. To further oil and gas cooperation with Central Asia, it is recommended that China should develop an energy acquisition strategy, assign a regional energy ambassador, enhance oil and gas supply by mergers and acquisitions, establish regional multinational subsidiaries and improve its risk prevention system.

Precipitation isotopes in the Tianshan Mountains as a key to water cycle in arid central Asia

The Tianshan Mountains is a wet island in arid central Asia, and precipitation amount across the mountains is much larger than that in the surrounding low-lying areas. To investigate the regional water cycle in arid central Asia, stable isotope composition in precipitation has received increased attention during the past decades. This paper reviewed current knowledge of observed and simulated stable isotope ratios in precipitation across the Tianshan Mountains. The temperature effect of stable isotopes in precipitation has been widely accepted in arid central Asia and can be applied to paleoclimate reconstruction using ice cores. The seasonality of precipitation isotopically enriched in summer months and depleted in winter months is usually attributed to westerly-dominated moisture, but different trajectory paths to the northern and southern slopes of the Tianshan Mountains can still be modelled. The proportional contribution and its uncertainty of surface evaporation and transpiration to local precipitation can be estimated using the isotope approach, and transpiration plays a dominant role in recycled moisture for oasis sites. The impact of below-cloud evaporation on precipitation stable isotopes on the southern slope is usually larger than that on the northern slope.

Precipitation trends and variability from 1950 to 2000 in arid lands of Central Asia

Climate warming will cause differences in precipitation distribution and changes in hydrological cycle both at regional and global scales. Arid lands of Central Asia （ALCA）, one of the largest arid regions at the middle latitudes in the world, is likely to be strongly influenced by climate warming. Understanding the precipitation varia- tions in the past is an important prerequisite for predicting future precipitation trends and thus managing regional water resources in such an arid region. In this study, we used run theory, displacement, extreme deviation theory, precipitation concentration index （PCI）, Mann-Kendall rank correlation and climatic trend coefficient methods to analyze the precipitation in wet and dry years, changes in precipitation over multiple-time scales, variability of precipitation and its rate of change based on the monthly precipitation data during 1950-2000 from 344 meteorological stations in the ALCA. The occurrence probability of a single year with abundant precipitation was higher than that of a single year with less precipitation. The average duration of extreme drought in the entire area was 5 years, with an average annual water deficit of 34.6 mm （accounting for 11.2% of the average annual precipitation over the duration）. The occurrence probability of a single wet year was slightly higher than that of a single dry year. The occurrence probability of more than 5 consecutive wet years was 5.8%, while the occurrence probability of more than 5 consecutive dry years was 6.2%. In the center of the study area, the distribution of precipitation was stable at an intra-annual timescale, with small changes at an inter-annual timescale. In the western part of the study area, the monthly variation of precipitation was high at an inter-annual timescale. There were clear seasonal changes in precipitation （PC1=12-36） in the ALCA. Precipitation in spring and winter accounted for 37.7% and 24.4% of the annual precipitation, respectively There was a significant inter-annual change in precipitation in the arid Northwest China （PC1=24-34）. Annual precipitation increased significantly （P=0.05） in 17.4% of all the meteorological stations over the study period. The probability of an increase in annual precipitation was 75.6%, with this increase being significant （P=-0.05） at 34.0% of all the meteorological stations. The average increasing rate in annual precipitation was 3.9 mm/10a （P=0.01） in the ALCA. There were significant increasing trends （P=0.01） in precipitation in Kazakhstan, Kyrgyzstan and Tajikistan, with rates of 2.6, 3.1 and 3.7 mm/10a, respectively.

Geological Characteristics and Metallogenic Setting of Representative Magmatic Cu-Ni Deposits in the Tianshan-Xingmeng Orogenic Belt, Central Asia

A great number of magmatic Cu-Ni deposits(including Kalatongke in Xinjiang and Hongqiling in Jilin) are distributed over a distance of almost 3000 km across the Tianshan-Xingmeng Orogenic Belt, from Tianshan Mountains in Xinjiang in the west, to Jilin in eastern China in the east. These deposits were formed during a range of magmatic episodes from the Devonian to the Triassic. Significant magmatic Cu-Ni-Co-PGE deposits were formed from the Devonian period in the Nalati arc(e.g. Jingbulake Cu-Ni in Xinjiang), Carboniferous period in the Puerjin-Ertai arc(e.g. Kalatongke Cu-Ni-Co-PGE in Xinjiang), Carboniferous period in the Dananhu-Touquan arc(e.g. Huangshandong, Xiangshan and Tulaergen in estern Tianshan, Xinjiang) to Triassic period in the Hulan arc(e.g. Hongqiling Cu-Ni in Jilin). In addition to the overall tectonic, geologic and distribution of magmatic Cu-Ni deposits in the Tianshan-Xingmeng Orogenic Belt, the metallogenic setting, deposit geology and mineralization characteristics of each deposit mentioned above are summarized in this paper. Geochronologic data of Cu-Ni deposits indicate that, from west to east, the metallogenic ages in the Tianshan-Xingmeng Orogenic Belt changed with time, namely, from the Late Caledonian(~440 Ma), through the Late Hercynian(300-265 Ma) to the Late Indosinian(225-200 Ma). Such variation could reflect a gradual scissor type closure of the paleo Asian ocean between the Siberia Craton and the North China Craton from west to east.

Applying the Moisture Availability Index (NTDI) over Vegetated Land in Central Asia: Mongolian Steppe

The intensity of recent droughts and the uncertainty of moisture variability in the context of increasing temperatures and decreasing precipitation have affected the Mongolian grassland. Mongolia typifies the steppe terrain and semiarid to arid continental climate that extends across much of Central Asia. In semi-arid areas like Mongolian steppe, vegetation type and distribution are directly relate to the amount of water that plants can extract from the soil. An index for assessment of moisture availability (ma: defined as the ratio of actual to reference evapotranspiration) was developed, namely NTDI [1] 08D0C9EA79F9BACE118C8200AA004BA90B02000000080000000E0000005F005200650066003400300031003800340037003500380031000000 . NTDI (Normalized Day-Night Surface Temperature Difference Index) is defined as the ratio of the difference between the maximum daytime surface temperature and the minimum nighttime surface temperature, to the difference between the maximum and minimum surface temperatures estimated from meteorological data by applying energy balance equations. A verification study conducted at Liudaogou River Basin of the Loess Plateau, China, indicated the capability of NTDI to estimate ma accurately, (R2=0.97,p<0.001) [1] 08D0C9EA79F9BACE118C8200AA004BA90B02000000080000000E0000005F005200650066003400300031003800340037003500380031000000 . In Bayan Unjuul, Mongolia, application of NTDI during the growing season showed a significant inverse exponential correlation with ma (R2=0.86,p<0.001). This result indicates that the NTDI is potent to be used as a surrogate of moisture availability in steppe terrain of Central Asia.

Analysis on exploitation status,potential and strategy of groundwater resources in the five countries of Central Asia

As an important part of water resources of the five countries of Central Asia,groundwater resources give critical supports to the regional economic development.Accompanied by rapid economic development,the demand of groundwater is increasing.As a result,the governments are paying more attention to groundwater resource development and utilization.However,there are noticeable issues and contradictions in water resource exploration in these countries.To be more specific,these countries lack the studies in development potential and conception planning,thus influencing the sustainable groundwater development.This paper mainly discusses groundwater development problems in the five countries of Central Asia,and briefly introduces volumes and distribution of transboundary groundwater.In addition,it analyzes the current exploitation status of groundwater and studies the potential in utilizing the resource.Most importantly,it proposes creative ways to address groundwater development issues:To make best of the resource,international cooperation is required.

Central Asia revealed as a key area in evolution of Eremurus (Asphodelaceae)

Eremurus was described at the beginning of the 19th century.However,due to limited sampling and the small number of gene markers to date,its phylogeny and evolution are largely unknown.In this study,we analyzed plastomes from 27 species belonging to 2 subgenera and 3 sections of Eremurus,which are found in Central Asia(its center of diversity)and China.We also analyzed nuclear DNA ITS of 33 species,encompassing all subgenera and sections of the genus in Central Asia,southwest Asia and China.Our findings revealed that the genus was monophyletic,although both subgenera Eremurus and Henningia were found to be paraphyletic.Both plastome and nrDNA-based phylogenetic trees had three clades that did not reflect the current taxonomy of the genus.Our biogeographical and time-calibrated trees suggest that Eremurus originated in the ancient Tethyan area in the second half of the Eocene.Diversification of Eremurus occurred from the early Oligocene to the late Miocene.Paratethys Sea retreat and several orogenetic events,such as the progressive uplift of the Qinghai-Tibet Plateau and surrounding mountain belts(Altai,Pamir,Tian Shan),caused serious topographic and climate(aridification)changes in Central Asia that may have triggered a split of clades and speciation.In this transformed Central Asia,speciation proceeded rapidly driven mainly by vicariance caused by numerous mountain chains and specialization to a variety of climatic,topographic and soil conditions that exist in this region.

Plastic-Flow/Seismic" Network Systems and Tectonic Units in Central-Eastern Asia

The study of the netlike earthquake distribution indicates that in the central-eastern part of Asia continent there are two network systems: the central-eastern Asia system and the southeastern China system.As interpreted by the multilayer tectonic model,they might be a manifestation of the plastic-flow network systems in the lower lithosphere,including the lower crust and the mantle lid.Each network system is enclosed by different types of boundaries,including one driving boundary and some constraining and releasing boundaries.The two plastic-flow network systems with the Himalayan and Taiwan arcs as their driving boundaries play the role of controlling the intraplate tectonic deformation,stress field,seismicity,and subdivision of tectonic units.

亚洲中东部岩石圈网状塑性流动控制下的多层应变速率场

根据“网状塑性流动”大陆动力学模型,岩石圈的变形方式由浅层脆性向深层延性的转变以及岩石圈下层网状塑性流动的控制作用,导致板块内部的多层构造变形。GPS方法或断层错动反演方法所测定的只是浅表地壳。多震层的应变速率可用“地震复发间隔法”,根据先后两次地震的复发间隔和后发地震的发震概率予以估计。基于岩石圈下层塑性流动网络共轭角与挤压变形之间的关系,可运用“共轭角法”估计该层的应变,并结合对于变形时间的估计,进一步推算网络的特征应变速率。文中给出了亚洲中东部地区岩石圈下层特征应变速率的等值线图,其数量级为10-15～10-14/s。控制多震层地震活动的主要是塑性流动网带,其应变速率大于网络的特征应变速率,除此以外,多震层的应变速率还受到驱动边界的直接作用、塑性流动波和上下层之间非连续分布软弱层的影响。根据青藏高原至华北平原11个潜在震源区所在地段多震层应变速率与岩石圈下层特征应变速率的对比分析,除临汾盆地1处偏差较大外,其余10处两者间表现出显著的线性相关,其比值β平均为1.75,分布范围为1.25～2.25。文中建议在进行中长期地震预测时,可根据岩石圈下层特征应变速率等值线图,结合比值β的引入,粗略地估计各潜在震源区的应变速率;同时,在β的取值上,尽可能地注意到驱动边界和相对稳定地块对该处各地段的影响。

The Global Energy and Water Exchanges(GEWEX)Project in Central Asia:The Case for a Regional Hydroclimate Project

Central Asia consists of the former Soviet Republics,Kazakhstan,Kyrgyz Republic,Tajikistan,Turkmenistan,and Uzbekistan.The region’s climate is continental,mostly semi-arid to arid.Agriculture is a significant part of the region’s economy.By its nature of intensive water use,agriculture is extremely vulnerable to climate change.Population growth and irrigation development have significantly increased the demand for water in the region.Major climate change issues include melting glaciers and a shrinking snowpack,which are the foundation of the region’s water resources,and a changing precipitation regime.Most glaciers are located in Kyrgyzstan and Tajikistan,leading to transboundary water resource issues.Summer already has extremely high temperatures.Analyses indicate that Central Asia has been warming and precipitation might be increasing.The warming is expected to increase,but its spatial and temporal distribution depends upon specific global scenarios.Projections of future precipitation show significant uncertainties in type,amount,and distribution.Regional Hydroclimate Projects(RHPs)are an approach to studying these issues.Initial steps to develop an RHP began in 2021 with a widely distributed online survey about these climate issues.It was followed up with an online workshop and then,in 2023,an in-person workshop,held in Tashkent,Uzbekistan.Priorities for the Global Energy and Water Exchanges(GEWEX)project for the region include both observations and modeling,as well as development of better and additional precipitation observations,all of which are topics for the next workshop.A well-designed RHP should lead to reductions in critical climate uncertainties in policy-relevant timeframes that can influence decisions on necessary investments in climate adaptation.