Climate change is the phrase used to describe long-term changes in temperatures and weather patterns. Changes in the atmosphere and their interactions with diverse geologic, chemical, biological, and geographic variab...Climate change is the phrase used to describe long-term changes in temperatures and weather patterns. Changes in the atmosphere and their interactions with diverse geologic, chemical, biological, and geographic variables are the main contributors to this cyclical adjustment of the Earth’s climate. Such changes may be induced purposefully, because of burning fossil fuels, clearing forests, and raising animals, or they may be natural, brought on by significant volcanic eruptions or variations in the sun’s activity. By significantly increasing the amount of greenhouse gases already in the atmosphere, this heightens the greenhouse effect and contributes to global warming. This work includes several additional theoretical and practical explanations of sustainable development. The theoretical work encompasses hundreds of researches that identify requirements for how development routes might satisfy sustainable development (SD) criteria using economic theory, complex systems approach, ecological science, and other techniques. The agreements made by the Parties in various nations across the world will consider a wide range of perspectives about what would be considered undesirable effects on the environment, the climate system, sustainability, economic growth, or food production.展开更多
This paper examines possible connections between volcanic eruptions and their consequences on the weather. Gas emissions, such as CO<sub>2</sub> and SO<sub>2</sub>, are vital in the troposphere...This paper examines possible connections between volcanic eruptions and their consequences on the weather. Gas emissions, such as CO<sub>2</sub> and SO<sub>2</sub>, are vital in the troposphere and change temperatures on Earth’s surface. The water vapor discharges can be moved for three atmospheric layers creating extra atmospheric rivers and disrupting the Polar vortex. All those deviations will bring consequences to the weather. It depends on the intensity, the emission type, the kind of volcano, and the location. Then, eruptions can change the atmospheric layers with sudden fluctuations unexpected for the season.展开更多
Central Asia is located in the hinterland of Eurasia,comprising Kazakhstan,Uzbekistan,Kyrgyzstan,Turkmenistan,and Tajikistan;over 93.00%of the total area is dryland.Temperature rise and human activities have severe im...Central Asia is located in the hinterland of Eurasia,comprising Kazakhstan,Uzbekistan,Kyrgyzstan,Turkmenistan,and Tajikistan;over 93.00%of the total area is dryland.Temperature rise and human activities have severe impacts on the fragile ecosystems.Since the 1970s,nearly half the great lakes in Central Asia have shrunk and rivers are drying rapidly owing to climate changes and human activities.Water shortage and ecological crisis have attracted extensive international attention.In general,ecosystem services in Central Asia are declining,particularly with respect to biodiversity,water,and soil conservation.Furthermore,the annual average temperature and annual precipitation in Central Asia increased by 0.30℃/decade and 6.9 mm/decade in recent decades,respectively.Temperature rise significantly affected glacier retreat in the Tianshan Mountains and Pamir Mountains,which may intensify water shortage in the 21st century.The increase in precipitation cannot counterbalance the aggravation of water shortage caused by the temperature rise and human activities in Central Asia.The population of Central Asia is growing gradually,and its economy is increasing steadily.Moreover,the agricultural land has not been expended in the last two decades.Thus,water and ecological crises,such as the Aral Sea shrinkage in the 21st century,cannot be attributed to agriculture extension any longer.Unbalanced regional development and water interception/transfer have led to the irrational exploitation of water resources in some watersheds,inducing downstream water shortage and ecological degradation.In addition,accelerated industrialization and urbanization have intensified this process.Therefore,all Central Asian countries must urgently reach a consensus and adopt common measures for water and ecological protection.展开更多
[Objective] The aim was to study the characteristics of climate changes in the surrounding area of Qinghai Lake.[Method] Based on the data of temperature,precipitation and sunshine hours from 5 representative meteorol...[Objective] The aim was to study the characteristics of climate changes in the surrounding area of Qinghai Lake.[Method] Based on the data of temperature,precipitation and sunshine hours from 5 representative meteorological stations in the surrounding area of Qinghai Lake during 1961-2007,the annual,seasonal and decadal variation of meteorological factors were analyzed.[Result] In recent 47 years,temperature showed obvious increase trend in the surrounding area of Qinghai Lake,and annual average temperature increased with the climatic tendency of ≥0.30 ℃/10 a,while annual average minimum temperature increased more significant than annual average temperature and annual average maximum temperature;annual mean precipitation decreased with the climatic tendency of-3.67 mm/10 a,and precipitation in spring and autumn reduced obviously,while precipitation in summer and winter increased slightly;annual sunshine hours also showed decrease trend with the climatic tendency of-1.79 h/10 a,while sunshine hours decreased most obviously in summer,and next came winter,while there was no obvious decrease in spring and autumn.[Conclusion] The study could provide theoretical references for the effective prevention of meteorological disasters in the surrounding area of Qinghai Lake.展开更多
The future global climate changes induced by the increased atmospheric CO2 concentration is receiving much attention from the scientific community as well as the public. Model simulations and palaeoclimatic data studi...The future global climate changes induced by the increased atmospheric CO2 concentration is receiving much attention from the scientific community as well as the public. Model simulations and palaeoclimatic data studies show an evident change in temperature and precipitation over China will occur under conditions of the global warming. Possible scenarios of the future climates are given here for China on the basis of synthesizing model simulations and palaeoclimatic data. Most parts of China will experience an increase in temperature, but the warming may be more remarkable in winter in h1e northern half of the country. Increase in precipitation will be seen in nearly every parts of the eastern China, and it will be larger in North and Northeast China. Impacts of the climate changes on the national tourism are assessed. Regions suitable for tourisin development in terms of climate comfortable index will shift northward. Some scenic spots and toruism facilities will be damaged due to sea level rise and increased rainfall. Some regions will benefit from the dimate change, but the tourism industry as a whole will be negatively affected.展开更多
In this study, the climate changes over Arid Central Asia(ACA) during the mid-Holocene(approximately 6,000 calendar years ago, MH) and the Last Glacial Maximum(approximately 21,000 calendar years ago, LGM) were invest...In this study, the climate changes over Arid Central Asia(ACA) during the mid-Holocene(approximately 6,000 calendar years ago, MH) and the Last Glacial Maximum(approximately 21,000 calendar years ago, LGM) were investigated using multimodel simulations derived from the Paleoclimate Modelling Intercomparison Project Phase 3(PMIP3). During the MH, the multimodel median(MMM) shows that in the core region of ACA, the regionally averaged annual surface air temperature(SAT) decreases by 0.13°C and annual precipitation decreases by 3.45%, compared with the preindustrial(PI) climate. The MMM of the SAT increases by 1.67/0.13°C in summer/autumn, whereas it decreases by 1.23/1.11°C in spring/winter. The amplitude of the seasonal cycles of the SAT increases over ACA due to different MH orbital parameters. For precipitation, the regionally averaged MMM decreases by 5.77%/5.69%/0.39%/5.24% in spring/summer/autumn/winter, respectively. Based on the analysis of the aridity index(AI), compared with the PI, a drier climate appears in southern Central Asia and western Xinjiang due to decreasing precipitation. During the LGM, the MMM shows that the regionally averaged SAT decreases by 5.04/4.36/4.70/5.12/5.88°C and precipitation decreases by 27.78%/28.16%/31.56%/27.74%/23.29% annually and in the spring, summer, autumn, and winter, respectively. Robust drying occurs throughout almost the whole core area. Decreasing precipitation plays a dominant role in shaping the drier conditions, whereas strong cooling plays a secondary but opposite role. In response to the LGM external forcings, over Central Asia and Xinjiang, the seasonal cycle of precipitation has a smaller amplitude compared with that under the PI climate. In the model-data comparison, the simulated MH moisture changes over ACA are to some extent consistent with the reconstructions, further confirming that drier conditions occurred during that period than during the PI.展开更多
[Objective] The response of surface water resources on climate changes was studied.[Method] By dint of monthly average temperature and precipitation in 45 meteorological stations in Jilin Province from 1960 to 2000,mo...[Objective] The response of surface water resources on climate changes was studied.[Method] By dint of monthly average temperature and precipitation in 45 meteorological stations in Jilin Province from 1960 to 2000,monthly runoff in 56 hydrological stations in Songhuajiang and Liaohe region,the surface runoff change and the response of surface water resources to climate change in 41 years were expounded.[Result] The runoff of Songliao region was limited during 1960s and 1970s.It began to increase slowly in the early 1980s.Since 1990s,there were distinct fluctuation of annual runoff and it was decreasing in general.EOF analysis suggested that the runoff of Songliao region was decreasing gradually from south to the north.The central gradient was small and runoff was evenly distributed.MK test result showed that the annual runoff in Songliao region had large fluctuation before 1980s and after 1990s.The response of surface runoff on climate and precipitation changes in Jilin Province was distinct and had strong relevance as well as certain lagging.Based on the analysis of the relation of rivers runoff and meteorological elements changes,statistics forecast model between river surface runoff and meteorological elements was constructed.Runoff prediction value and measured value had good relation.The corresponding river surface runoff changes can be assessed based on the changes of meteorological elements.[Conclusion] The study provided theoretical basis for the development and utilization of surface water resources in Jilin.展开更多
Agriculture received most direct influences from climate changes. Because of climate changes, agricultural climate resources changed and thus influenced climate adaptability of agricultural products. The growth and ou...Agriculture received most direct influences from climate changes. Because of climate changes, agricultural climate resources changed and thus influenced climate adaptability of agricultural products. The growth and output of crops were finally affected. The calculation method and application of agricultural products in recent years were summarized. Several questions about the response of agricultural crops to climate elements were proposed for attention.展开更多
Comprehensive assessments of ecosystem services in environments under the influences of human activities and climate change are critical for sustainable regional ecosystem management. Therefore,integrated interdiscipl...Comprehensive assessments of ecosystem services in environments under the influences of human activities and climate change are critical for sustainable regional ecosystem management. Therefore,integrated interdisciplinary modelling has become a major focus of ecosystem service assessment. In this study, we established a model that integrates land use/cover change(LUCC), climate change, and water retention services to evaluate the spatial and temporal variations of water retention services in the Loess Plateau of China in the historical period(2000–2015) and in the future(2020–2050). An improved Markov-Cellular Automata(Markov-CA) model was used to simulate land use/land cover patterns, and ArcGIS 10.2 software was used to simulate and assess water retention services from 2000 to 2050 under six combined scenarios, including three land use/land cover scenarios(historical scenario(HS), ecological protection scenario(EPS), and urban expansion scenario(UES)) and two climate change scenarios(RCP4.5 and RCP8.5, where RCP is the representative concentration pathway). LUCCs in the historical period(2000–2015) and in the future(2020–2050) are dominated by transformations among agricultural land, urban land and grassland. Urban land under UES increased significantly by 0.63×10^(3) km^(2)/a, which was higher than the increase of urban land under HS and EPS. In the Loess Plateau, water yield decreased by 17.20×10^(6) mm and water retention increased by 0.09×10^(6) mm in the historical period(2000–2015),especially in the Interior drainage zone and its surrounding areas. In the future(2020–2050), the pixel means of water yield is higher under RCP4.5 scenario(96.63 mm) than under RCP8.5 scenario(95.46mm), and the pixel means of water retention is higher under RCP4.5 scenario(1.95 mm) than under RCP8.5 scenario(1.38 mm). RCP4.5-EPS shows the highest total water retention capacity on the plateau scale among the six combined scenarios, with the value of 1.27×10^(6) mm. Ecological restoration projects in the Loess Plateau have enhanced soil and water retention. However, more attention needs to be paid not only to the simultaneous increase in water retention services and evapotranspiration but also to the type and layout of restored vegetation. Furthermore, urbanization needs to be controlled to prevent uncontrollable LUCCs and climate change. Our findings provide reference data for the regional water and land resources management and the sustainable development of socio-ecological systems in the Loess Plateau under LUCC and climate change scenarios.展开更多
This paper is a study to understand how climate changed last fifty years. There are two theories: the first one considers the solar variability and the influence of those alterations on climate;the second one blames h...This paper is a study to understand how climate changed last fifty years. There are two theories: the first one considers the solar variability and the influence of those alterations on climate;the second one blames human activity and the consequences on temperatures and disruption on the environment created by humans. Our conclusions pointed out that dimensions involved between Earth and Sun, and Earth/Atmosphere, the second one can disturb the temperature on Earth’s surface and make seasonality variations impossible to be explained only by Sun/Earth connections.展开更多
Reconstructions of past climatic changes on the northeastern Tibetan Plateau(NETP) can provide insights into the Asian summer monsoon(ASM) variability. However, the regional climate changes on both orbital and suborbi...Reconstructions of past climatic changes on the northeastern Tibetan Plateau(NETP) can provide insights into the Asian summer monsoon(ASM) variability. However, the regional climate changes on both orbital and suborbital time scales since the late Glacial remain controversial. Here we present the results of high-resolution geochemical and grain-size analyses of a sediment core from Genggahai Lake, a small, shallow lake in this area. Changes of the accumulation rate of the core sediments show a similar trend with variations of the coarse fraction. Accordingly, the chronological framework is constructed using a grain-size age model. In addition, the histories of chemical weathering and aeolian activity since the late Glacial are reconstructed based on the Al/Ti ratios and coarse fractions, respectively. The results suggest that an enhanced chemical weathering and a weakened aeolian activity occurred on the NETP under a warmer, wetter climate during the early to mid-Holocene(11.3–6.3 ka cal BP), compared with the late Glacial(17.1–11.3 ka cal BP) and the late Holocene(6.3 ka cal BP to present), which responded mainly to the strengthened ASM on orbital time scale. In addition, the synchronous occurrences of weakened chemical weathering, low lake level and intense aeolian activity on suborbital time scale reflect several episodes of weakened ASM. Furthermore, these episodes largely coincide with the centennial-to millennial-scale cold events in the North Atlantic, which demonstrates the close connection between the ASM and the cooling at high latitudes.展开更多
Phylogeographic patterns of endemic species are critical keys to understand its adaptation to future climate change.Herein,based on chloroplast DNA,we analyzed the genetic diversity of two endemic and endangered tree ...Phylogeographic patterns of endemic species are critical keys to understand its adaptation to future climate change.Herein,based on chloroplast DNA,we analyzed the genetic diversity of two endemic and endangered tree species from the Brazilian savanna and Atlantic forest(Eremanthus erythropappus and Eremanthus incanus).We also applied the climate-based ecological niche modeling(ENM)to evaluate the impact of the Quaternary climate(last glacial maximum*21 kyr BP(thousand years before present)and Mid-Holocene*6 kyr BP)on the current haplotype distribution.Moreover,we modeled the potential effect of future climate change on the species distribution in 2070 for the most optimistic and pessimistic scenarios.One primer/enzyme combination(SFM/HinfI)revealed polymorphism with very low haplotype diversity,showing only three different haplotypes.The haplotype 1 has very low frequency and it was classified as the oldest,diverging from six mutations from the haplotypes 2 and 3.The E.erythropappus populations are structured and differ genetically according to the areas of occurrence.In general,the populations located in the north region are genetically different from those located in the center-south.No genetic structuring was observed for E.incanus.The ENM revealed a large distribution during the past and a severe decrease in geographic distribution of E.erythropappus and E.incanus from the LGM until present and predicts a drastic decline in suitable areas in the future.This reduction may homogenize the genetic diversity and compromise a relevant role of these species on infiltration of groundwater.展开更多
There is an increasing number of "mass events" in China's Mainland.My study extends the current studies to the context of China and tries to examine the potential impacts of climate changes on human conf...There is an increasing number of "mass events" in China's Mainland.My study extends the current studies to the context of China and tries to examine the potential impacts of climate changes on human conflias in China.The results suggest a strong linkage between the deviation of monthly mean temperature from the historical mean and the number of mass events in a province.If the current trend of warming persists,in the next 6-8 decades,the number of mass events in China will increase by over 8.8%.展开更多
Potentiometric and pluviometric datasets were evaluated to understand the behavior of aquifer recharge in the bauxite plateaus in the Porto Trombetas region, Pará, Northern Brazil. The datasets are originated fro...Potentiometric and pluviometric datasets were evaluated to understand the behavior of aquifer recharge in the bauxite plateaus in the Porto Trombetas region, Pará, Northern Brazil. The datasets are originated from three monitoring wells and an automatic climatological station. The local groundwater is related to the Alter do Chao Aquifer System, which despite being unconfined in valley regions, is semiconfined in the plateaus areas. The aquifer recharge occurs by direct infiltration and by leakage from the aquitard in the unconfined and semiconfined portions, respectively. Precipitation declined by 27% between 2002 and 2017. The rains accumulated between February and April are the most important for the recharge processes since this period is marked by higher absolute precipitation (up to 300 mm/month) and less deviation from the historical pattern. The recharge measured by the annual fluctuation of the water table also declined significantly in the 2010-2016 period. Statistical analysis demonstrates that in the case of a permanent climate change, expressed by rainfall reducing, the aquifer recharge would diminish at a non-linear rate, which is also expected for the base flow rates. In addition, data evaluation reveals that deforestation intensely decreases the recharge rates, as observed in the Aviso Plateau mining site. The results demonstrate that the water table fluctuations must be considered when modeling Global Climate Changes since the maintenance of surface flow rates (springs, lakes and streams) depends on aquifers baseflow. The result of the statistical analysis can be also applied to regions where climate patterns are strong seasonal, as the Savannah of Central Brazil.展开更多
Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by drought.Understanding the impact of droughts on different types of vegetation...Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by drought.Understanding the impact of droughts on different types of vegetation GPP provides insight into the spatiotemporal variation of terrestrial carbon sinks,aiding efforts to mitigate the detrimental effects of climate change.In this study,we utilized the precipitation and temperature data from the Climatic Research Unit,the standardized precipitation evapotranspiration index(SPEI),the standardized precipitation index(SPI),and the simulated vegetation GPP using the eddy covariance-light use efficiency(EC-LUE)model to analyze the spatiotemporal change of GPP and its response to different drought indices in the Mongolian Plateau during 1982-2018.The main findings indicated that vegetation GPP decreased in 50.53% of the plateau,mainly in its northern and northeastern parts,while it increased in the remaining 49.47%area.Specifically,meadow steppe(78.92%)and deciduous forest(79.46%)witnessed a significant decrease in vegetation GPP,while alpine steppe(75.08%),cropland(76.27%),and sandy vegetation(87.88%)recovered well.Warming aridification areas accounted for 71.39% of the affected areas,while 28.53% of the areas underwent severe aridification,mainly located in the south and central regions.Notably,the warming aridification areas of desert steppe(92.68%)and sandy vegetation(90.24%)were significant.Climate warming was found to amplify the sensitivity of coniferous forest,deciduous forest,meadow steppe,and alpine steppe GPP to drought.Additionally,the drought sensitivity of vegetation GPP in the Mongolian Plateau gradually decreased as altitude increased.The cumulative effect of drought on vegetation GPP persisted for 3.00-8.00 months.The findings of this study will improve the understanding of how drought influences vegetation in arid and semi-arid areas.展开更多
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...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.展开更多
Seasonal snow cover is a key global climate and hydrological system component drawing considerable attention due to glob-al warming conditions.However,the spatiotemporal snow cover patterns are challenging in western ...Seasonal snow cover is a key global climate and hydrological system component drawing considerable attention due to glob-al warming conditions.However,the spatiotemporal snow cover patterns are challenging in western Jilin,China due to natural condi-tions and sparse observation.Hence,this study investigated the spatiotemporal patterns of snow cover using fine-resolution passive mi-crowave(PMW)snow depth(SD)data from 1987 to 2018,and revealed the potential influence of climate factors on SD variations.The results indicated that the interannual range of SD was between 2.90 cm and 9.60 cm during the snowy winter seasons and the annual mean SD showed a slightly increasing trend(P>0.05)at a rate of 0.009 cm/yr.In snowmelt periods,the snow cover contributed to an increase in volumetric soil water,and the change in SD was significantly affected by air temperature.The correlation between SD and air temperature was negative,while the correlation between SD and precipitation was positive during December and March.In March,the correlation coefficient exceeded 0.5 in Zhenlai,Da’an,Qianan,and Qianguo counties.However,the SD and precipitation were neg-atively correlated over western Jilin in October,and several subregions presented a negative correlation between SD and precipitation in November and April.展开更多
This study addresses the link between social media use and pro-environmental civic participation considering the moderating effect of social media affordances (public realm) on one hand, and lifestyle behaviors and cl...This study addresses the link between social media use and pro-environmental civic participation considering the moderating effect of social media affordances (public realm) on one hand, and lifestyle behaviors and climate change experiences (personal realm) on the other. We combine communication theory and behavioral models and using a sample of USA individuals (N = 7225) based on the American Trends Panel to predict variations in pro-environmental behavior. We show that social networks rather than information are more effective in predicting pro-environmental behavior. Moreover, a pro-environmental lifestyle as well as climate change experiences at the community level increase the likelihood for pro-environmental participation. However, affordances related to socioeconomic variations generate variations to pro-environmental civic participation. We conclude that in order to capture the depth of pro-environmental civic participation, it is necessary to theoretically and empirically bridge between private and public expressions of pro-environmental awareness.展开更多
Studying the significant impacts on vegetation of drought due to global warming is crucial in order to understand its dynamics and interrelationships with temperature,rainfall,and normalized difference vegetation inde...Studying the significant impacts on vegetation of drought due to global warming is crucial in order to understand its dynamics and interrelationships with temperature,rainfall,and normalized difference vegetation index(NDVI).These factors are linked to excesses drought frequency and severity on the regional scale,and their effect on vegetation remains an important topic for climate change study.East Asia is very sensitive and susceptible to climate change.In this study,we examined the effect of drought on the seasonal variations of vegetation in relation to climate variability and determined which growing seasons are most vulnerable to drought risk;and then explored the spatio-temporal evolution of the trend in drought changes in East Asia from 1982 to 2019.The data were studied using a series of several drought indexes,and the data were then classified using a heat map,box and whisker plot analysis,and principal component analysis.The various drought indexes from January to August improved rapidly,except for vegetation health index(VHI)and temperature condition index(TCI).While these indices were constant in September,they increased again in October,but in December,they showed a descending trend.The seasonal and monthly analysis of the drought indexes and the heat map confirmed that the East Asian region suffered from extreme droughts in 1984,1993,2007,and 2012among the study years.The distribution of the trend in drought changes indicated that more severe drought occurred in the northwestern region than in the southeastern area of East Asia.The drought tendency slope was used to describe the changes in drought events during 1982–2019 in the study region.The correlations among monthly precipitation anomaly percentage(NAP),NDVI,TCI,vegetation condition index(VCI),temperature vegetation drought index(TVDI),and VHI indicated considerably positive correlations,while considerably negative correlations were found among the three pairs of NDVI and VHI,TVDI and VHI,and NDVI and TCI.This ecological and climatic mechanism provides a good basis for the assessment of vegetation and drought-change variations within the East Asian region.This study is a step forward in monitoring the seasonal variation of vegetation and variations in drought dynamics within the East Asian region,which will serve and contribute to the better management of vegetation,disaster risk,and drought in the East Asian region.展开更多
Zabuye Salt Lake(ZSL)in Xizang is the only saline lake in the world with natural crystalline lithium carbonate.As it is an important lithium production base in China,any changes of this lake are concerning.Global clim...Zabuye Salt Lake(ZSL)in Xizang is the only saline lake in the world with natural crystalline lithium carbonate.As it is an important lithium production base in China,any changes of this lake are concerning.Global climate change(CC)has affected the hydrological conditions of glaciers,lakes,and ecosystems in the Tibetan Plateau(TP).With the aim of monitoring dynamic hydrological changes in ZSL and Lunggar Glaciers(LG)to identify factors governing lake changes,and to estimate the potential damage to grasslands and salt pans,Landsat remote sensing(RS)and meteorological data were used to do a series of experiments and analysis.Firstly,according to the spectral characteristics(SC),salt lake,glaciers,grasslands,and salt pans around the salt lake were extracted by band calculation(BC).Secondly,basin and water areas of the expanded lake were estimated using a shuttle radar topography mission(SRTM)digital elevation model(DEM).Thirdly,comprehensive analyses of lake and glacier area changes,and regional meteorological factors(annual average temperature,annual precipitation,and evaporation)were performed,and the results show that ZSL expanded at a rate of 5.28 km^(2)/a,it is likely to continue expanding.Expansion was closely related to the large-scale melting of a glacier caused by rising temperatures.Continued lake expansion(LE)will exert different effects on surrounding grasslands and salt pans,7.84 km^(2)of grassland and 2.7 km^(2)of salt pan will be submerged with every meter of water increase in the lake.Similar prediction methods was used to monitor other lakes on the TP.Mami Co,Selin Co,and Chaerhan salt lakes all expanded at different rates,and may potentially cause different levels of potential harm to surrounding grasslands and roads.Our study contributes to salt lake research and demonstrates the superiority of RS technology for monitoring saline lakes.展开更多
文摘Climate change is the phrase used to describe long-term changes in temperatures and weather patterns. Changes in the atmosphere and their interactions with diverse geologic, chemical, biological, and geographic variables are the main contributors to this cyclical adjustment of the Earth’s climate. Such changes may be induced purposefully, because of burning fossil fuels, clearing forests, and raising animals, or they may be natural, brought on by significant volcanic eruptions or variations in the sun’s activity. By significantly increasing the amount of greenhouse gases already in the atmosphere, this heightens the greenhouse effect and contributes to global warming. This work includes several additional theoretical and practical explanations of sustainable development. The theoretical work encompasses hundreds of researches that identify requirements for how development routes might satisfy sustainable development (SD) criteria using economic theory, complex systems approach, ecological science, and other techniques. The agreements made by the Parties in various nations across the world will consider a wide range of perspectives about what would be considered undesirable effects on the environment, the climate system, sustainability, economic growth, or food production.
文摘This paper examines possible connections between volcanic eruptions and their consequences on the weather. Gas emissions, such as CO<sub>2</sub> and SO<sub>2</sub>, are vital in the troposphere and change temperatures on Earth’s surface. The water vapor discharges can be moved for three atmospheric layers creating extra atmospheric rivers and disrupting the Polar vortex. All those deviations will bring consequences to the weather. It depends on the intensity, the emission type, the kind of volcano, and the location. Then, eruptions can change the atmospheric layers with sudden fluctuations unexpected for the season.
基金This work was supported by the Strategic Priority Research Program of the Chinese Academy of Sciences:the Pan-Third Pole Environment Study for a Green Silk Road(XDA20060303)the CAS''Light of West China''Program(2018-XBQNXZ-B-017)the''High-level Talents Program''of Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences(Y871171).Special thanks are given to the Philosophy and Social Science Major Research Project"Research on the Major Risk Prevention System in the Development of Artificial Intelligence"(20JZD026)funded by the Ministry of Education of the People's Republic of China.
文摘Central Asia is located in the hinterland of Eurasia,comprising Kazakhstan,Uzbekistan,Kyrgyzstan,Turkmenistan,and Tajikistan;over 93.00%of the total area is dryland.Temperature rise and human activities have severe impacts on the fragile ecosystems.Since the 1970s,nearly half the great lakes in Central Asia have shrunk and rivers are drying rapidly owing to climate changes and human activities.Water shortage and ecological crisis have attracted extensive international attention.In general,ecosystem services in Central Asia are declining,particularly with respect to biodiversity,water,and soil conservation.Furthermore,the annual average temperature and annual precipitation in Central Asia increased by 0.30℃/decade and 6.9 mm/decade in recent decades,respectively.Temperature rise significantly affected glacier retreat in the Tianshan Mountains and Pamir Mountains,which may intensify water shortage in the 21st century.The increase in precipitation cannot counterbalance the aggravation of water shortage caused by the temperature rise and human activities in Central Asia.The population of Central Asia is growing gradually,and its economy is increasing steadily.Moreover,the agricultural land has not been expended in the last two decades.Thus,water and ecological crises,such as the Aral Sea shrinkage in the 21st century,cannot be attributed to agriculture extension any longer.Unbalanced regional development and water interception/transfer have led to the irrational exploitation of water resources in some watersheds,inducing downstream water shortage and ecological degradation.In addition,accelerated industrialization and urbanization have intensified this process.Therefore,all Central Asian countries must urgently reach a consensus and adopt common measures for water and ecological protection.
基金Supported by National Key Technology R & D Program (2007BAC30B02)Science and Technology Key Project of Qinghai Province (2008-N-146)
文摘[Objective] The aim was to study the characteristics of climate changes in the surrounding area of Qinghai Lake.[Method] Based on the data of temperature,precipitation and sunshine hours from 5 representative meteorological stations in the surrounding area of Qinghai Lake during 1961-2007,the annual,seasonal and decadal variation of meteorological factors were analyzed.[Result] In recent 47 years,temperature showed obvious increase trend in the surrounding area of Qinghai Lake,and annual average temperature increased with the climatic tendency of ≥0.30 ℃/10 a,while annual average minimum temperature increased more significant than annual average temperature and annual average maximum temperature;annual mean precipitation decreased with the climatic tendency of-3.67 mm/10 a,and precipitation in spring and autumn reduced obviously,while precipitation in summer and winter increased slightly;annual sunshine hours also showed decrease trend with the climatic tendency of-1.79 h/10 a,while sunshine hours decreased most obviously in summer,and next came winter,while there was no obvious decrease in spring and autumn.[Conclusion] The study could provide theoretical references for the effective prevention of meteorological disasters in the surrounding area of Qinghai Lake.
文摘The future global climate changes induced by the increased atmospheric CO2 concentration is receiving much attention from the scientific community as well as the public. Model simulations and palaeoclimatic data studies show an evident change in temperature and precipitation over China will occur under conditions of the global warming. Possible scenarios of the future climates are given here for China on the basis of synthesizing model simulations and palaeoclimatic data. Most parts of China will experience an increase in temperature, but the warming may be more remarkable in winter in h1e northern half of the country. Increase in precipitation will be seen in nearly every parts of the eastern China, and it will be larger in North and Northeast China. Impacts of the climate changes on the national tourism are assessed. Regions suitable for tourisin development in terms of climate comfortable index will shift northward. Some scenic spots and toruism facilities will be damaged due to sea level rise and increased rainfall. Some regions will benefit from the dimate change, but the tourism industry as a whole will be negatively affected.
基金This research was supported by the National Key R&D Program of China (Grant No. 2018YFA0606403)the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No. XDA20070103)+1 种基金the National Natural Science Foundation of China (Grants 41822502)the CAS–PKU Joint Research Program
文摘In this study, the climate changes over Arid Central Asia(ACA) during the mid-Holocene(approximately 6,000 calendar years ago, MH) and the Last Glacial Maximum(approximately 21,000 calendar years ago, LGM) were investigated using multimodel simulations derived from the Paleoclimate Modelling Intercomparison Project Phase 3(PMIP3). During the MH, the multimodel median(MMM) shows that in the core region of ACA, the regionally averaged annual surface air temperature(SAT) decreases by 0.13°C and annual precipitation decreases by 3.45%, compared with the preindustrial(PI) climate. The MMM of the SAT increases by 1.67/0.13°C in summer/autumn, whereas it decreases by 1.23/1.11°C in spring/winter. The amplitude of the seasonal cycles of the SAT increases over ACA due to different MH orbital parameters. For precipitation, the regionally averaged MMM decreases by 5.77%/5.69%/0.39%/5.24% in spring/summer/autumn/winter, respectively. Based on the analysis of the aridity index(AI), compared with the PI, a drier climate appears in southern Central Asia and western Xinjiang due to decreasing precipitation. During the LGM, the MMM shows that the regionally averaged SAT decreases by 5.04/4.36/4.70/5.12/5.88°C and precipitation decreases by 27.78%/28.16%/31.56%/27.74%/23.29% annually and in the spring, summer, autumn, and winter, respectively. Robust drying occurs throughout almost the whole core area. Decreasing precipitation plays a dominant role in shaping the drier conditions, whereas strong cooling plays a secondary but opposite role. In response to the LGM external forcings, over Central Asia and Xinjiang, the seasonal cycle of precipitation has a smaller amplitude compared with that under the PI climate. In the model-data comparison, the simulated MH moisture changes over ACA are to some extent consistent with the reconstructions, further confirming that drier conditions occurred during that period than during the PI.
文摘[Objective] The response of surface water resources on climate changes was studied.[Method] By dint of monthly average temperature and precipitation in 45 meteorological stations in Jilin Province from 1960 to 2000,monthly runoff in 56 hydrological stations in Songhuajiang and Liaohe region,the surface runoff change and the response of surface water resources to climate change in 41 years were expounded.[Result] The runoff of Songliao region was limited during 1960s and 1970s.It began to increase slowly in the early 1980s.Since 1990s,there were distinct fluctuation of annual runoff and it was decreasing in general.EOF analysis suggested that the runoff of Songliao region was decreasing gradually from south to the north.The central gradient was small and runoff was evenly distributed.MK test result showed that the annual runoff in Songliao region had large fluctuation before 1980s and after 1990s.The response of surface runoff on climate and precipitation changes in Jilin Province was distinct and had strong relevance as well as certain lagging.Based on the analysis of the relation of rivers runoff and meteorological elements changes,statistics forecast model between river surface runoff and meteorological elements was constructed.Runoff prediction value and measured value had good relation.The corresponding river surface runoff changes can be assessed based on the changes of meteorological elements.[Conclusion] The study provided theoretical basis for the development and utilization of surface water resources in Jilin.
基金Supported by Scientific Research Special Fund for Public Welfare Industry (Meteorology) (201106020)China Meteorological BureauClimate Changes Special Fund (CCSF-09-12)
文摘Agriculture received most direct influences from climate changes. Because of climate changes, agricultural climate resources changed and thus influenced climate adaptability of agricultural products. The growth and output of crops were finally affected. The calculation method and application of agricultural products in recent years were summarized. Several questions about the response of agricultural crops to climate elements were proposed for attention.
基金supported by the State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau(A314021402–202110)the Science Foundation of Hubei Province,China(2021CFB295)the National Natural Science Foundation of China(42077451)。
文摘Comprehensive assessments of ecosystem services in environments under the influences of human activities and climate change are critical for sustainable regional ecosystem management. Therefore,integrated interdisciplinary modelling has become a major focus of ecosystem service assessment. In this study, we established a model that integrates land use/cover change(LUCC), climate change, and water retention services to evaluate the spatial and temporal variations of water retention services in the Loess Plateau of China in the historical period(2000–2015) and in the future(2020–2050). An improved Markov-Cellular Automata(Markov-CA) model was used to simulate land use/land cover patterns, and ArcGIS 10.2 software was used to simulate and assess water retention services from 2000 to 2050 under six combined scenarios, including three land use/land cover scenarios(historical scenario(HS), ecological protection scenario(EPS), and urban expansion scenario(UES)) and two climate change scenarios(RCP4.5 and RCP8.5, where RCP is the representative concentration pathway). LUCCs in the historical period(2000–2015) and in the future(2020–2050) are dominated by transformations among agricultural land, urban land and grassland. Urban land under UES increased significantly by 0.63×10^(3) km^(2)/a, which was higher than the increase of urban land under HS and EPS. In the Loess Plateau, water yield decreased by 17.20×10^(6) mm and water retention increased by 0.09×10^(6) mm in the historical period(2000–2015),especially in the Interior drainage zone and its surrounding areas. In the future(2020–2050), the pixel means of water yield is higher under RCP4.5 scenario(96.63 mm) than under RCP8.5 scenario(95.46mm), and the pixel means of water retention is higher under RCP4.5 scenario(1.95 mm) than under RCP8.5 scenario(1.38 mm). RCP4.5-EPS shows the highest total water retention capacity on the plateau scale among the six combined scenarios, with the value of 1.27×10^(6) mm. Ecological restoration projects in the Loess Plateau have enhanced soil and water retention. However, more attention needs to be paid not only to the simultaneous increase in water retention services and evapotranspiration but also to the type and layout of restored vegetation. Furthermore, urbanization needs to be controlled to prevent uncontrollable LUCCs and climate change. Our findings provide reference data for the regional water and land resources management and the sustainable development of socio-ecological systems in the Loess Plateau under LUCC and climate change scenarios.
文摘This paper is a study to understand how climate changed last fifty years. There are two theories: the first one considers the solar variability and the influence of those alterations on climate;the second one blames human activity and the consequences on temperatures and disruption on the environment created by humans. Our conclusions pointed out that dimensions involved between Earth and Sun, and Earth/Atmosphere, the second one can disturb the temperature on Earth’s surface and make seasonality variations impossible to be explained only by Sun/Earth connections.
基金This research was supported by the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No. XDA20090000)the National Natural Science Foundation of China (Grants 41901103)the Foundation for Excellent Youth Scholars of "Northwest Institute of Eco-Environment and Resources", CAS
文摘Reconstructions of past climatic changes on the northeastern Tibetan Plateau(NETP) can provide insights into the Asian summer monsoon(ASM) variability. However, the regional climate changes on both orbital and suborbital time scales since the late Glacial remain controversial. Here we present the results of high-resolution geochemical and grain-size analyses of a sediment core from Genggahai Lake, a small, shallow lake in this area. Changes of the accumulation rate of the core sediments show a similar trend with variations of the coarse fraction. Accordingly, the chronological framework is constructed using a grain-size age model. In addition, the histories of chemical weathering and aeolian activity since the late Glacial are reconstructed based on the Al/Ti ratios and coarse fractions, respectively. The results suggest that an enhanced chemical weathering and a weakened aeolian activity occurred on the NETP under a warmer, wetter climate during the early to mid-Holocene(11.3–6.3 ka cal BP), compared with the late Glacial(17.1–11.3 ka cal BP) and the late Holocene(6.3 ka cal BP to present), which responded mainly to the strengthened ASM on orbital time scale. In addition, the synchronous occurrences of weakened chemical weathering, low lake level and intense aeolian activity on suborbital time scale reflect several episodes of weakened ASM. Furthermore, these episodes largely coincide with the centennial-to millennial-scale cold events in the North Atlantic, which demonstrates the close connection between the ASM and the cooling at high latitudes.
文摘Phylogeographic patterns of endemic species are critical keys to understand its adaptation to future climate change.Herein,based on chloroplast DNA,we analyzed the genetic diversity of two endemic and endangered tree species from the Brazilian savanna and Atlantic forest(Eremanthus erythropappus and Eremanthus incanus).We also applied the climate-based ecological niche modeling(ENM)to evaluate the impact of the Quaternary climate(last glacial maximum*21 kyr BP(thousand years before present)and Mid-Holocene*6 kyr BP)on the current haplotype distribution.Moreover,we modeled the potential effect of future climate change on the species distribution in 2070 for the most optimistic and pessimistic scenarios.One primer/enzyme combination(SFM/HinfI)revealed polymorphism with very low haplotype diversity,showing only three different haplotypes.The haplotype 1 has very low frequency and it was classified as the oldest,diverging from six mutations from the haplotypes 2 and 3.The E.erythropappus populations are structured and differ genetically according to the areas of occurrence.In general,the populations located in the north region are genetically different from those located in the center-south.No genetic structuring was observed for E.incanus.The ENM revealed a large distribution during the past and a severe decrease in geographic distribution of E.erythropappus and E.incanus from the LGM until present and predicts a drastic decline in suitable areas in the future.This reduction may homogenize the genetic diversity and compromise a relevant role of these species on infiltration of groundwater.
文摘There is an increasing number of "mass events" in China's Mainland.My study extends the current studies to the context of China and tries to examine the potential impacts of climate changes on human conflias in China.The results suggest a strong linkage between the deviation of monthly mean temperature from the historical mean and the number of mass events in a province.If the current trend of warming persists,in the next 6-8 decades,the number of mass events in China will increase by over 8.8%.
文摘Potentiometric and pluviometric datasets were evaluated to understand the behavior of aquifer recharge in the bauxite plateaus in the Porto Trombetas region, Pará, Northern Brazil. The datasets are originated from three monitoring wells and an automatic climatological station. The local groundwater is related to the Alter do Chao Aquifer System, which despite being unconfined in valley regions, is semiconfined in the plateaus areas. The aquifer recharge occurs by direct infiltration and by leakage from the aquitard in the unconfined and semiconfined portions, respectively. Precipitation declined by 27% between 2002 and 2017. The rains accumulated between February and April are the most important for the recharge processes since this period is marked by higher absolute precipitation (up to 300 mm/month) and less deviation from the historical pattern. The recharge measured by the annual fluctuation of the water table also declined significantly in the 2010-2016 period. Statistical analysis demonstrates that in the case of a permanent climate change, expressed by rainfall reducing, the aquifer recharge would diminish at a non-linear rate, which is also expected for the base flow rates. In addition, data evaluation reveals that deforestation intensely decreases the recharge rates, as observed in the Aviso Plateau mining site. The results demonstrate that the water table fluctuations must be considered when modeling Global Climate Changes since the maintenance of surface flow rates (springs, lakes and streams) depends on aquifers baseflow. The result of the statistical analysis can be also applied to regions where climate patterns are strong seasonal, as the Savannah of Central Brazil.
基金jointly supported by the National Natural Science Foundation of China(42361024,42101030,42261079,and 41961058)the Talent Project of Science and Technology in Inner Mongolia of China(NJYT22027 and NJYT23019)the Fundamental Research Funds for the Inner Mongolia Normal University,China(2022JBBJ014 and 2022JBQN093)。
文摘Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by drought.Understanding the impact of droughts on different types of vegetation GPP provides insight into the spatiotemporal variation of terrestrial carbon sinks,aiding efforts to mitigate the detrimental effects of climate change.In this study,we utilized the precipitation and temperature data from the Climatic Research Unit,the standardized precipitation evapotranspiration index(SPEI),the standardized precipitation index(SPI),and the simulated vegetation GPP using the eddy covariance-light use efficiency(EC-LUE)model to analyze the spatiotemporal change of GPP and its response to different drought indices in the Mongolian Plateau during 1982-2018.The main findings indicated that vegetation GPP decreased in 50.53% of the plateau,mainly in its northern and northeastern parts,while it increased in the remaining 49.47%area.Specifically,meadow steppe(78.92%)and deciduous forest(79.46%)witnessed a significant decrease in vegetation GPP,while alpine steppe(75.08%),cropland(76.27%),and sandy vegetation(87.88%)recovered well.Warming aridification areas accounted for 71.39% of the affected areas,while 28.53% of the areas underwent severe aridification,mainly located in the south and central regions.Notably,the warming aridification areas of desert steppe(92.68%)and sandy vegetation(90.24%)were significant.Climate warming was found to amplify the sensitivity of coniferous forest,deciduous forest,meadow steppe,and alpine steppe GPP to drought.Additionally,the drought sensitivity of vegetation GPP in the Mongolian Plateau gradually decreased as altitude increased.The cumulative effect of drought on vegetation GPP persisted for 3.00-8.00 months.The findings of this study will improve the understanding of how drought influences vegetation in arid and semi-arid areas.
基金The National Research University Tashkent Institute of Irrigation and Agricultural Mechanization Engineers of Uzbekistan hosted and provided financial support for the in-person workshop in May of 2023
文摘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.
基金Under the auspices of the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA28110502)Science and Technology Development Plan Project of Jilin Province(No.20220202035NC)+1 种基金National Natural Science Foundation of China(No.41871248)Changchun Science and Technology Development Plan Project(No.21ZY12)。
文摘Seasonal snow cover is a key global climate and hydrological system component drawing considerable attention due to glob-al warming conditions.However,the spatiotemporal snow cover patterns are challenging in western Jilin,China due to natural condi-tions and sparse observation.Hence,this study investigated the spatiotemporal patterns of snow cover using fine-resolution passive mi-crowave(PMW)snow depth(SD)data from 1987 to 2018,and revealed the potential influence of climate factors on SD variations.The results indicated that the interannual range of SD was between 2.90 cm and 9.60 cm during the snowy winter seasons and the annual mean SD showed a slightly increasing trend(P>0.05)at a rate of 0.009 cm/yr.In snowmelt periods,the snow cover contributed to an increase in volumetric soil water,and the change in SD was significantly affected by air temperature.The correlation between SD and air temperature was negative,while the correlation between SD and precipitation was positive during December and March.In March,the correlation coefficient exceeded 0.5 in Zhenlai,Da’an,Qianan,and Qianguo counties.However,the SD and precipitation were neg-atively correlated over western Jilin in October,and several subregions presented a negative correlation between SD and precipitation in November and April.
文摘This study addresses the link between social media use and pro-environmental civic participation considering the moderating effect of social media affordances (public realm) on one hand, and lifestyle behaviors and climate change experiences (personal realm) on the other. We combine communication theory and behavioral models and using a sample of USA individuals (N = 7225) based on the American Trends Panel to predict variations in pro-environmental behavior. We show that social networks rather than information are more effective in predicting pro-environmental behavior. Moreover, a pro-environmental lifestyle as well as climate change experiences at the community level increase the likelihood for pro-environmental participation. However, affordances related to socioeconomic variations generate variations to pro-environmental civic participation. We conclude that in order to capture the depth of pro-environmental civic participation, it is necessary to theoretically and empirically bridge between private and public expressions of pro-environmental awareness.
基金the Basic Research Project of Zhejiang Normal University,China(ZC304022952)the China Postdoctoral Science Foundation Funding(2018M642614)the Natural Science Foundation Youth Proj ect of S h andong Provi nce,C hina(ZR2020QF281)。
文摘Studying the significant impacts on vegetation of drought due to global warming is crucial in order to understand its dynamics and interrelationships with temperature,rainfall,and normalized difference vegetation index(NDVI).These factors are linked to excesses drought frequency and severity on the regional scale,and their effect on vegetation remains an important topic for climate change study.East Asia is very sensitive and susceptible to climate change.In this study,we examined the effect of drought on the seasonal variations of vegetation in relation to climate variability and determined which growing seasons are most vulnerable to drought risk;and then explored the spatio-temporal evolution of the trend in drought changes in East Asia from 1982 to 2019.The data were studied using a series of several drought indexes,and the data were then classified using a heat map,box and whisker plot analysis,and principal component analysis.The various drought indexes from January to August improved rapidly,except for vegetation health index(VHI)and temperature condition index(TCI).While these indices were constant in September,they increased again in October,but in December,they showed a descending trend.The seasonal and monthly analysis of the drought indexes and the heat map confirmed that the East Asian region suffered from extreme droughts in 1984,1993,2007,and 2012among the study years.The distribution of the trend in drought changes indicated that more severe drought occurred in the northwestern region than in the southeastern area of East Asia.The drought tendency slope was used to describe the changes in drought events during 1982–2019 in the study region.The correlations among monthly precipitation anomaly percentage(NAP),NDVI,TCI,vegetation condition index(VCI),temperature vegetation drought index(TVDI),and VHI indicated considerably positive correlations,while considerably negative correlations were found among the three pairs of NDVI and VHI,TVDI and VHI,and NDVI and TCI.This ecological and climatic mechanism provides a good basis for the assessment of vegetation and drought-change variations within the East Asian region.This study is a step forward in monitoring the seasonal variation of vegetation and variations in drought dynamics within the East Asian region,which will serve and contribute to the better management of vegetation,disaster risk,and drought in the East Asian region.
基金Supported by the Academician Workstation Projects of the Institute of Mineral Resources,Chinese Academy of Geological Sciences(Nos.HE 2205,HE 2206,KK 2012)the National Natural Science Foundation of China(No.42172332)+1 种基金the China Geological Survey Project(No.DD 20221684)the Basic Research Projects of the Institute of Mineral Resources,Chinese Academy of Geological Sciences(No.KK 2102)。
文摘Zabuye Salt Lake(ZSL)in Xizang is the only saline lake in the world with natural crystalline lithium carbonate.As it is an important lithium production base in China,any changes of this lake are concerning.Global climate change(CC)has affected the hydrological conditions of glaciers,lakes,and ecosystems in the Tibetan Plateau(TP).With the aim of monitoring dynamic hydrological changes in ZSL and Lunggar Glaciers(LG)to identify factors governing lake changes,and to estimate the potential damage to grasslands and salt pans,Landsat remote sensing(RS)and meteorological data were used to do a series of experiments and analysis.Firstly,according to the spectral characteristics(SC),salt lake,glaciers,grasslands,and salt pans around the salt lake were extracted by band calculation(BC).Secondly,basin and water areas of the expanded lake were estimated using a shuttle radar topography mission(SRTM)digital elevation model(DEM).Thirdly,comprehensive analyses of lake and glacier area changes,and regional meteorological factors(annual average temperature,annual precipitation,and evaporation)were performed,and the results show that ZSL expanded at a rate of 5.28 km^(2)/a,it is likely to continue expanding.Expansion was closely related to the large-scale melting of a glacier caused by rising temperatures.Continued lake expansion(LE)will exert different effects on surrounding grasslands and salt pans,7.84 km^(2)of grassland and 2.7 km^(2)of salt pan will be submerged with every meter of water increase in the lake.Similar prediction methods was used to monitor other lakes on the TP.Mami Co,Selin Co,and Chaerhan salt lakes all expanded at different rates,and may potentially cause different levels of potential harm to surrounding grasslands and roads.Our study contributes to salt lake research and demonstrates the superiority of RS technology for monitoring saline lakes.