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Estimating Terrestrial Water Storage (TWS) not only helps to provide a comprehensive insight into water resource variability and the hydrological cycle but also for better water resource management. In the current research, Gravity Recovery And Climate Experiment (GRACE) data are combined with the available hydrological data to reconstruct a longer record of Terrestrial Water Storage Anomalies (TWSA) prior to 2003 of the Tarim River Basin (TRB), based on a Long Short-Term Memory (LSTM) model. We found that the TWSA generated by LSTM using soil moisture, evapotranspiration, precipitation, and temperature best matches the GRACE-derived TWSA, with a high correlation coefficient (r) of 0.922 and a Normalized Root Mean Square Error (NRMSE) of 0.107 during the period 2003–2012. These results show that the LSTM model is an available and feasible method to generate TWSA. Further, the TWSA reveals a significant fluctuating downward trend (p < 0.001), with an average decline rate of 0.03 mm/month during the period 1982–2016 in the TRB. Moreover, the TWSA amount in the north of the TRB was less than that in the south of the basin. Overall, our findings unveiled that the LSTM model and GRACE data can be combined effectively to analyze the long-term TWSA in large-scale basins with limited hydrological data.
Fei Wang; Yaning Chen; Zhi Li; Gonghuan Fang; Yupeng Li; Xuanxuan Wang; Xueqi Zhang; Patient Kayumba. Developing a Long Short-Term Memory (LSTM)-Based Model for Reconstructing Terrestrial Water Storage Variations from 1982 to 2016 in the Tarim River Basin, Northwest China. Remote Sensing 2021, 13, 889 .
AMA StyleFei Wang, Yaning Chen, Zhi Li, Gonghuan Fang, Yupeng Li, Xuanxuan Wang, Xueqi Zhang, Patient Kayumba. Developing a Long Short-Term Memory (LSTM)-Based Model for Reconstructing Terrestrial Water Storage Variations from 1982 to 2016 in the Tarim River Basin, Northwest China. Remote Sensing. 2021; 13 (5):889.
Chicago/Turabian StyleFei Wang; Yaning Chen; Zhi Li; Gonghuan Fang; Yupeng Li; Xuanxuan Wang; Xueqi Zhang; Patient Kayumba. 2021. "Developing a Long Short-Term Memory (LSTM)-Based Model for Reconstructing Terrestrial Water Storage Variations from 1982 to 2016 in the Tarim River Basin, Northwest China." Remote Sensing 13, no. 5: 889.
Central Asia, located in the hinterland of the Eurasian continent, is characterized with sparse rainfall, frequent droughts and low water use efficiency. Limited water resources have become a key factor restricting the sustainable development of this region. Accurately assessing the efficiency of water resources utilization is the first step to achieve the UN Sustainable Development Goals (SDGs) in Central Asia. However, since the collapse of the Soviet Union, the evaluation of water use efficiency is difficult due to low data availability and poor consistency. To fill this gap, this paper developed a Water Use Efficiency dataset (WUE) based on the Moderate Resolution Imaging Spectroradiometer (MODIS) Gross Primary Production (GPP) data and the MODIS evapotranspiration (ET) data. The WUE dataset ranges from 2000 to 2019 with a spatial resolution of 500 m. The agricultural WUE was then extracted based on the Global map of irrigated areas and MODIS land use map. As a complementary, the water use amount per GDP was estimated for each country. The present dataset could reflect changes in water use efficiency of agriculture and other sectors. The published data are available at http://www.dx.doi.org/10.11922/sciencedb.j00076.00012.
Yaning Chen; Gonghuan Fang; Haichao Hao; Xuanxuan Wang. Water use efficiency data from 2000 to 2019 in measuring progress towards SDGs in Central Asia. Big Earth Data 2020, 1 -13.
AMA StyleYaning Chen, Gonghuan Fang, Haichao Hao, Xuanxuan Wang. Water use efficiency data from 2000 to 2019 in measuring progress towards SDGs in Central Asia. Big Earth Data. 2020; ():1-13.
Chicago/Turabian StyleYaning Chen; Gonghuan Fang; Haichao Hao; Xuanxuan Wang. 2020. "Water use efficiency data from 2000 to 2019 in measuring progress towards SDGs in Central Asia." Big Earth Data , no. : 1-13.
In the arid region of northwestern China (ARNC), water resources are the most critical factor restricting socioeconomic development and influencing the stability of the area's ecological systems. The region's complex water system and unique hydrological cycle show distinctive characteristics. Moreover, the intensified hydrological cycle and extreme climatic and hydrological events resulting from global warming have led to increased uncertainty around water resources as well as heightened conflict between water supply and water demand. All of these factors are exerting growing pressures on the socioeconomic development and vulnerable ecological environment in the region. This research evaluates the impacts of climate change on water resources, hydrological processes, agricultural system, and desert ecosystems in the ARNC, and addresses some associated risks and challenges specific to this area. The temperature is rising at a rate of 0.31 °C per decade during 1961–2017 and hydrological processes are being significantly influenced by changes in glaciers, snow cover, and precipitation form, especially in the rivers recharged primarily by melt water. Ecosystems are also largely influenced by climate change, with the Normalized Difference Vegetation Index (NDVI) of natural vegetation exhibited an increasing trend prior to 1998, and then reversed in Xinjiang while the Hexi Corridor of Gansu showed the opposite trends. Furthermore, the desert-oasis transition zone showed a reduction in area due to the warming trend and the recent rapid expansion of irrigated area. Both the warming and intensified drought are threatening agriculture security. The present study could shed light on sustainable development in this region under climate change and provides scientific basis to the construction of the “Silk Road Economic Belt”.
Yaning Chen; Xueqi Zhang; Gonghuan Fang; Zhi Li; Fei Wang; Jingxiu Qin; Fan Sun. Potential risks and challenges of climate change in the arid region of northwestern China. Regional Sustainability 2020, 1, 20 -30.
AMA StyleYaning Chen, Xueqi Zhang, Gonghuan Fang, Zhi Li, Fei Wang, Jingxiu Qin, Fan Sun. Potential risks and challenges of climate change in the arid region of northwestern China. Regional Sustainability. 2020; 1 (1):20-30.
Chicago/Turabian StyleYaning Chen; Xueqi Zhang; Gonghuan Fang; Zhi Li; Fei Wang; Jingxiu Qin; Fan Sun. 2020. "Potential risks and challenges of climate change in the arid region of northwestern China." Regional Sustainability 1, no. 1: 20-30.
Global warming has generally led to changes in river runoffs fed by snow and glacier meltwater in mountain ranges. The runoff of the Aksu River, which originates in the Southern Tienshan Mountains, exhibited a positive trend during 1979–2002, but this trend reversed during 2002–2015. Through a comprehensive analysis, this study aims to estimate potential reasons for changes in the runoff of its two contrasting headwaters: the Toxkan and Kumalak Rivers, based on climatic data, the altitude of the 0 °C isotherm, glacier mass balance (GMB), snow cover area (SCA), snow depth (SD) and the sensitivity model. For the Toxkan River, the decrease in spring runoff mainly resulted from reductions in precipitation, whereas the decrease in summer runoff was mainly caused by early snowmelt in spring and a much-reduced snow meltwater supply in summer. In addition, the obvious glacier area reduction in the catchment (decreased to less than 4%) also contributed to the reduced summer runoff. For the Kumalak River, a sharp decrease rate of 10.21 × 108 m3/decade in runoff was detected due to summertime cooling of both surface and upper air temperatures. Reduced summer temperatures with a positive trend in precipitation not only inhibited glacier melting but also dropped the 0 °C layer altitude, resulting in a significant increase in summertime SCA and SD, a slowing of the glacier negative mass balance, and a lowering of the snow-line altitude.
Qifei Zhang; Yaning Chen; Zhi Li; Gonghuan Fang; Yanyun Xiang; Yupeng Li; Huiping Ji. Recent Changes in Water Discharge in Snow and Glacier Melt-Dominated Rivers in the Tienshan Mountains, Central Asia. Remote Sensing 2020, 12, 2704 .
AMA StyleQifei Zhang, Yaning Chen, Zhi Li, Gonghuan Fang, Yanyun Xiang, Yupeng Li, Huiping Ji. Recent Changes in Water Discharge in Snow and Glacier Melt-Dominated Rivers in the Tienshan Mountains, Central Asia. Remote Sensing. 2020; 12 (17):2704.
Chicago/Turabian StyleQifei Zhang; Yaning Chen; Zhi Li; Gonghuan Fang; Yanyun Xiang; Yupeng Li; Huiping Ji. 2020. "Recent Changes in Water Discharge in Snow and Glacier Melt-Dominated Rivers in the Tienshan Mountains, Central Asia." Remote Sensing 12, no. 17: 2704.
The utilization of water resources and water security in Central Asia are critical to the stability of the region. This paper assesses the water security of the five Central Asian countries (Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan) by using the projection pursuit model based on particle swarm optimization (PSO-PEE). The results show that the average annual water consumption in Central Asia is about 1255.57 × 108 m3, and the proportion of agricultural water consumption decreased due in large part to the changes of crop planting structure. For the ecological security, Kazakhstan, Tajikistan and Kyrgyzstan have improved their status, but Turkmenistan is getting worse. For the quantity security of water resources, Tajikistan and Kyrgyzstan are relatively safe, whereas Uzbekistan is at risk. For the socio-economic conditions, Kazakhstan scored the highest, while Tajikistan and Uzbekistan scored the lowest, water consumption per 10,000 dollars of GDP across all five countries is relatively high but shows a significant decreasing trend. For the water supply and demand security, the status of Kazakhstan, Kyrgyzstan and Tajikistan are better than that of Turkmenistan and Uzbekistan. Kazakhstan has achieved a relatively safe level (level Ⅱ) and the degree of water security is high. Kyrgyzstan, Tajikistan and Turkmenistan are only in the basically safe level (level III). Uzbekistan is under significant pressure with regard to water security (level IV), which indicates that the country needs to strictly control population growth and strengthen the comprehensive management of water resources.
Xuanxuan Wang; Yaning Chen; Zhi Li; Gonghuan Fang; Yi Wang. Development and utilization of water resources and assessment of water security in Central Asia. Agricultural Water Management 2020, 240, 106297 .
AMA StyleXuanxuan Wang, Yaning Chen, Zhi Li, Gonghuan Fang, Yi Wang. Development and utilization of water resources and assessment of water security in Central Asia. Agricultural Water Management. 2020; 240 ():106297.
Chicago/Turabian StyleXuanxuan Wang; Yaning Chen; Zhi Li; Gonghuan Fang; Yi Wang. 2020. "Development and utilization of water resources and assessment of water security in Central Asia." Agricultural Water Management 240, no. : 106297.
In the arid region of Central Asia, climate change leads not only to changes in water availability generated by glacier/snow melt in the alpine regions, but also to changes in water consumption. This paper evaluates agricultural water demand and water supply (represented by precipitation) for the five Central Asian countries (Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan and Uzbekistan) under global warming conditions of 1.5 °C and 2.0 °C. As Central Asia is more sensitive to climate change compared to the global average, the temperature is predicted to rise by 1.7 °C and 2.6 °C and precipitation to increase by 9 % and 12 % in global warming scenarios of 1.5 °C and 2.0 °C, respectively. The average crop water requirement (CWR) is expected to increase by 13 mm and 19 mm per year, respectively, under the global warming scenarios of 1.5 °C and 2.0 °C. A widening gap between water supply and water demand is expected compared to the historical period (1976–2005) under global warming scenario of 2.0 °C. Under global warming of 2.0 °C, the anticipated water gaps between precipitation and CWR are projected to increase by 2.8 × 108 m3 and 1.5 × 108 m3 for the rainfed north Kazakhstan region and the irrigated Fergana region while the increase of precipitation could able to meet the increase in CWR under global warming of 1.5 °C. Investigating the water balance for major planting areas in water-limited Central Asia could provide a scientific basis for sustainable development of the entire region.
Zhi Li; Gonghuan Fang; Yaning Chen; Weili Duan; Yerbolat Mukanov. Agricultural water demands in Central Asia under 1.5 °C and 2.0 °C global warming. Agricultural Water Management 2020, 231, 106020 .
AMA StyleZhi Li, Gonghuan Fang, Yaning Chen, Weili Duan, Yerbolat Mukanov. Agricultural water demands in Central Asia under 1.5 °C and 2.0 °C global warming. Agricultural Water Management. 2020; 231 ():106020.
Chicago/Turabian StyleZhi Li; Gonghuan Fang; Yaning Chen; Weili Duan; Yerbolat Mukanov. 2020. "Agricultural water demands in Central Asia under 1.5 °C and 2.0 °C global warming." Agricultural Water Management 231, no. : 106020.
Although climate change has emerged as a major threat to biodiversity, few assessments exist of the sensitivity of desert riparian forests to climate in extremely arid plain areas. We mapped tree growth-climate correlations (time period: 1957–2015) to identify the sensitivities of Populus euphratica (P. euphratica), a dominant and important tree species in the desert riparian forest in the lower Tarim River, an extremely arid area in China, to climate change. The results indicated that groundwater depth was the key factor for controlling tree growth in the study area. In order to accurately assess sensitivity to climate change of the desert riparian forest, it was necessary to consider the effects of hydrological fluctuations on P. euphratica because the sensitivities of tree growth to precipitation and temperature depended on changes in the groundwater environment. The groundwater depth threshold to distinguish the sensitivity of climate change to P. euphratica growth was 6–7 m. Moreover, warming would accelerate desert riparian forest decline when the groundwater depth was more than 6 m because an anomalously high temperature would intensify evapotranspiration and the shortage of soil moisture during the growing season, and offset the benefits from precipitation, which would cause more drought if groundwater was not compensated by sufficient runoff. Therefore, global warming would bring great disadvantages to desert riparian forests if the current mode of the ecological water conveyance project (EWCP) continues to be implemented without a fixed time and water amount in the lower Tarim River, which could not steadily decrease and actively maintain shallow groundwater depth.
Honghua Zhou; Yaning Chen; Chenggang Zhu; Zhi Li; Gonghuan Fang; Yupeng Li; Aihong Fu. Climate change may accelerate the decline of desert riparian forest in the lower Tarim River, Northwestern China: Evidence from tree-rings of Populus euphratica. Ecological Indicators 2019, 111, 105997 .
AMA StyleHonghua Zhou, Yaning Chen, Chenggang Zhu, Zhi Li, Gonghuan Fang, Yupeng Li, Aihong Fu. Climate change may accelerate the decline of desert riparian forest in the lower Tarim River, Northwestern China: Evidence from tree-rings of Populus euphratica. Ecological Indicators. 2019; 111 ():105997.
Chicago/Turabian StyleHonghua Zhou; Yaning Chen; Chenggang Zhu; Zhi Li; Gonghuan Fang; Yupeng Li; Aihong Fu. 2019. "Climate change may accelerate the decline of desert riparian forest in the lower Tarim River, Northwestern China: Evidence from tree-rings of Populus euphratica." Ecological Indicators 111, no. : 105997.
Studying the relationship between agricultural irrigation water requirements (IWR) and water supply is significant for optimizing the sustainable management of water resources in Tarim River Basin (TRB). However, the related studies have not quantified the total IWR and the imbalance of irrigation water supply and requirements in the TRB. The study analyzed the spatial-temporal variations of IWR by a modified Penman–Monteith (PM) method during 1990–2015. Five major crops—rice, wheat, maize, cotton, and fruit trees—are chosen for calculating the IWR. It was found that the IWR increased significantly, from 193.14 × 108 m3 in 1990 to 471.89 × 108 m3 in 2015, for a total increase of 278.74 × 108 m3. For the first period (1990–2002), the total IWR remained stable at 200 × 108 m3 but started to increase from 2003 onwards. Significantly more irrigation water was consumed in the oasis regions of the Tienshan Mountains (southern slope) and the Yarkand River (plains). Furthermore, there was an intensified conflict between IWR and water supply in the major sub-basins. The ratios of IWR to river discharge (IWR/Q) for the Weigan-Kuqa River Basin (WKRB), Aksu River Basin (ARB), Kaxgar River Basin (KGRB), and Yarkand River Basin (YRB) were 0.93, 0.68, 1.05, and 0.79, respectively. The IWR/Q experienced serious annual imbalances, as high flows occurred in July and August, whereas critical high IWR occurred in May and June. Seasonal water shortages further aggravate the water stress in the arid region.
Fei Wang; Yaning Chen; Zhi Li; Gonghuan Fang; Yupeng Li; Zhenhua Xia. Assessment of the Irrigation Water Requirement and Water Supply Risk in the Tarim River Basin, Northwest China. Sustainability 2019, 11, 4941 .
AMA StyleFei Wang, Yaning Chen, Zhi Li, Gonghuan Fang, Yupeng Li, Zhenhua Xia. Assessment of the Irrigation Water Requirement and Water Supply Risk in the Tarim River Basin, Northwest China. Sustainability. 2019; 11 (18):4941.
Chicago/Turabian StyleFei Wang; Yaning Chen; Zhi Li; Gonghuan Fang; Yupeng Li; Zhenhua Xia. 2019. "Assessment of the Irrigation Water Requirement and Water Supply Risk in the Tarim River Basin, Northwest China." Sustainability 11, no. 18: 4941.
Soil moisture plays a critical role in land-atmosphere interactions. Quantifying the controls on soil moisture is highly valuable for effective management of water resources and climatic adaptation. In this study, we quantified the effects of precipitation, temperature, and vegetation on monthly soil moisture variability in an arid area, China. A non-linear Granger causality framework was applied to examine the causal effects based on multi-decadal reanalysis data records. Results indicate that precipitation had effects on soil moisture in about 91% of the study area and explained up to 40% of soil moisture variability during 1982–2015. Temperature and vegetation explained up to 8.2% and 3.3% of soil moisture variability, respectively. Climatic extremes were responsible for up to 10% of soil moisture variability, and the importance of climatic extremes was low compared to that of the general climate dynamics. The time-lagged analysis shows that the effects of precipitation and temperature on soil moisture were immediate and dissipated shortly. In addition, the effects of precipitation on soil moisture decreased with the increase of precipitation, soil moisture, and elevation. This study provides deep insight for uncovering the drivers of soil moisture variability in arid regions.
Yunqian Wang; Jing Yang; Yaning Chen; Gonghuan Fang; Weili Duan; Yupeng Li; Philippe De Maeyer. Quantifying the Effects of Climate and Vegetation on Soil Moisture in an Arid Area, China. Water 2019, 11, 767 .
AMA StyleYunqian Wang, Jing Yang, Yaning Chen, Gonghuan Fang, Weili Duan, Yupeng Li, Philippe De Maeyer. Quantifying the Effects of Climate and Vegetation on Soil Moisture in an Arid Area, China. Water. 2019; 11 (4):767.
Chicago/Turabian StyleYunqian Wang; Jing Yang; Yaning Chen; Gonghuan Fang; Weili Duan; Yupeng Li; Philippe De Maeyer. 2019. "Quantifying the Effects of Climate and Vegetation on Soil Moisture in an Arid Area, China." Water 11, no. 4: 767.
Understanding glacio-hydrological processes is crucial to water resources management, especially under increasing global warming. However, data scarcity makes it challenging to quantify the contribution of glacial melt to streamflow in highly glacierized catchments such as those in the Tienshan Mountains. This study aims to investigate the glacio-hydrological processes in the SaryDjaz-Kumaric River (SDKR) basin in Central Asia by integrating a degree-day glacier melt algorithm into the macro-scale hydrological Soil and Water Assessment Tool (SWAT) model. To deal with data scarcity in the alpine area, a multi-objective sensitivity analysis and a multi-objective calibration procedure were used to take advantage of all aspects of streamflow. Three objective functions, i.e., the Nash–Sutcliffe efficiency coefficient of logarithms (LogNS), the water balance index (WBI), and the mean absolute relative difference (MARD), were considered. Results show that glacier and snow melt-related parameters are generally sensitive to all three objective functions. Compared to the original SWAT model, simulations with a glacier module match fairly well to the observed streamflow, with the Nash–Sutcliffe efficiency coefficient (NS) and R2 approaching 0.82 and an absolute percentage bias less than 1%. Glacier melt contribution to runoff is 30–48% during the simulation period. The approach of combining multi-objective sensitivity analysis and optimization is an efficient way to identify important hydrological processes and recharge characteristics in highly glacierized catchments.
Huiping Ji; Gonghuan Fang; Jing Yang; Yaning Chen. Multi-Objective Calibration of a Distributed Hydrological Model in a Highly Glacierized Watershed in Central Asia. Water 2019, 11, 554 .
AMA StyleHuiping Ji, Gonghuan Fang, Jing Yang, Yaning Chen. Multi-Objective Calibration of a Distributed Hydrological Model in a Highly Glacierized Watershed in Central Asia. Water. 2019; 11 (3):554.
Chicago/Turabian StyleHuiping Ji; Gonghuan Fang; Jing Yang; Yaning Chen. 2019. "Multi-Objective Calibration of a Distributed Hydrological Model in a Highly Glacierized Watershed in Central Asia." Water 11, no. 3: 554.
The Penman‐Monteith (PM) method is considered the most accurate method for estimating reference crop evapotranspiration (ET0). However, the method has obvious flaws in energy balance closure. In this study, the changing trends between latent heat flux of ET0(LEp) and surface net radiation (Rn) in China were analysed based on observational data from 800 meteorological stations. The results showed that the multi‐year average ratio of LEp/Rn was highest in the warm temperate zone and was lowest in the sub‐frigid zone of the Tibetan Plateau. Correspondingly, the values of LEp/Rn in these areas were ranged from 1.138 to 0.647. At the site scale, there were 61, 178 and 170 meteorological stations with daily average LEp/Rn values > 1 during three periods (from Jan. to Apr., May to Aug. and Sep. to Dec., respectively). The ratio of LEp/Rn showed an obvious surface energy imbalance, and it was extremely obvious in northern China. Meanwhile, it is found that there was also great uncertainty of the ET0, which estimated based on the calculated and measured net radiation. In general, the uncertainty of ET0 was ranged from ‐0.955 mm/d to 1.028mm/d and the average value of uncertainty was 0.154 mm/d. The uncertainty also showed obviously temporal variation, which was lower during Apr. to Oct., but was higher in other times. The main cause of the energy balance closure problem was the overestimation of the aerodynamic component of ET0. In view of such situation, this study suggested the two ways to estimate ET0 for different regions.
Xingming Hao; Shuhua Zhang; Weihong Li; Weili Duan; Gonghuan Fang; Ying Zhang; Bin Guo. The Uncertainty of Penman-Monteith Method and the Energy Balance Closure Problem. Journal of Geophysical Research: Atmospheres 2018, 1 .
AMA StyleXingming Hao, Shuhua Zhang, Weihong Li, Weili Duan, Gonghuan Fang, Ying Zhang, Bin Guo. The Uncertainty of Penman-Monteith Method and the Energy Balance Closure Problem. Journal of Geophysical Research: Atmospheres. 2018; ():1.
Chicago/Turabian StyleXingming Hao; Shuhua Zhang; Weihong Li; Weili Duan; Gonghuan Fang; Ying Zhang; Bin Guo. 2018. "The Uncertainty of Penman-Monteith Method and the Energy Balance Closure Problem." Journal of Geophysical Research: Atmospheres , no. : 1.
Central Asia, which is one of the most complex regions in the world, is criss‐crossed with transboundary rivers shared by several countries. This paper analyzes the effects of climate change and human activities on hydrological processes and water resources in these transboundary rivers over the past half‐century. The results show that the average temperature in the Tienshan Mountains experienced "sharp" increases in 1998, with the average temperature after 1998 being 1.0 °C higher than that during 1960‐1998. This rapid warming has accelerated glacier shrinkage and decreases in snow cover. These changes influenced the hydrological processes, causing an earlier runoff peak and aggravated extreme hydrological events. Changes in mountainous hydrological processes affect regional water availability and intensified future water crisis in Central Asia. The mismatched spatial distributions of water and land resources, along with the intense human activities (e.g., over‐exploitation of water resources), have ultimately led to the present water crisis in Central Asia's river basins. This is the main reason for ongoing water conflicts in the region's transboundary rivers and the ecological disaster of the Aral Sea.
Yaning Chen; Zhi Li; Gonghuan Fang; Weihong Li. Large Hydrological Processes Changes in the Transboundary Rivers of Central Asia. Journal of Geophysical Research: Atmospheres 2018, 123, 5059 -5069.
AMA StyleYaning Chen, Zhi Li, Gonghuan Fang, Weihong Li. Large Hydrological Processes Changes in the Transboundary Rivers of Central Asia. Journal of Geophysical Research: Atmospheres. 2018; 123 (10):5059-5069.
Chicago/Turabian StyleYaning Chen; Zhi Li; Gonghuan Fang; Weihong Li. 2018. "Large Hydrological Processes Changes in the Transboundary Rivers of Central Asia." Journal of Geophysical Research: Atmospheres 123, no. 10: 5059-5069.
In arid areas, lakes play important roles in sustaining the local ecology, mitigating flood hazard, and restricting economic activity of society. In this study, we used multi-temporal satellite data to study annual variations in 16 natural lakes with individual surface areas over 10 km2, categorized into six regions based on their geographical and climatic information and on their relations with climate variables. Results indicated that annual variations in lake surface areas are different across these six regions. The surface area of Kanas Lake has not obviously changed due to its typical U-shape cross section; the areas of Ulungur Lake and Jili Lake increased sharply in the 1980s and then slightly decreased; the areas of Sayram Lake, Ebinur Lake, and Bosten Lake increased and then decreased, with peaks detected in the early 2000s; the areas of Barkol Lake and Toale Culler decreased, while those of the lakes located in the Kunlun Mountains steadily increased. Lake areas also show various relationships with climate variables. There is no obvious relationship between area and climate variables in Kanas Lake due to the specific lake morphology; the areas of most lakes showed positive correlations with annual precipitation (except Sayram Lake). A negative correlation between area and temperature were detected in Ulungur Lake, Jili Lake, Barkol Lake, and Toale Culler, while positive correlations were suggested in Bosten Lake and the lakes in the Kunlun Mountains (e.g., Saligil Kollakan Lake, Aksai Chin Lake, and Urukkule Lake).
Yuting Liu; Jing Yang; Yaning Chen; Gonghuan Fang; Weihong Li. The Temporal and Spatial Variations in Lake Surface Areas in Xinjiang, China. Water 2018, 10, 431 .
AMA StyleYuting Liu, Jing Yang, Yaning Chen, Gonghuan Fang, Weihong Li. The Temporal and Spatial Variations in Lake Surface Areas in Xinjiang, China. Water. 2018; 10 (4):431.
Chicago/Turabian StyleYuting Liu; Jing Yang; Yaning Chen; Gonghuan Fang; Weihong Li. 2018. "The Temporal and Spatial Variations in Lake Surface Areas in Xinjiang, China." Water 10, no. 4: 431.
Agricultural water use accounts for more than 95% of the total water consumption in the extreme arid region of the Tarim River Basin. Understanding the variation of agricultural water demand (AWD) and its attributions is therefore vital for irrigation management and water resource allocation affecting the economy and natural ecosystems in this high water-deficit region. Here spatial–temporal variations of AWD based on weighted crop water requirement (ETc) were estimated using the Penman–Monteith equation and the crop coefficient approach. Then the contributions of meteorological factors and planting structure (i.e. proportions of crop acreages) to AWD variations were quantified based on traditional methods and numerical experiment (i.e. a series calculation of AWD based on different input data). Results indicated that AWD decreased during 1960–1988 at a rate of 2.76 mm/year and then started to increase at a high rate of 9.47 mm/year during 1989–2015. For the first period (1960–1988), wind speed (uz), maximum humidity (RHmax) and sunshine duration (n) were the most important factors leading to decreased AWD, while for the second period the evolution of planting structure was the most significant factor resulting in the rapid increase of AWD, followed by the minimum temperature (Tmin), uz and RHmax. The evolution of planting structure alone would lead to an increase rate for AWD of 7.1 mm/year while the climatic factor would result in an increase rate of 1.9 mm/year during 1989–2015.
G. Fang; Y. Chen; Z. Li. Variation in agricultural water demand and its attributions in the arid Tarim River Basin. The Journal of Agricultural Science 2018, 156, 301 -311.
AMA StyleG. Fang, Y. Chen, Z. Li. Variation in agricultural water demand and its attributions in the arid Tarim River Basin. The Journal of Agricultural Science. 2018; 156 (3):301-311.
Chicago/Turabian StyleG. Fang; Y. Chen; Z. Li. 2018. "Variation in agricultural water demand and its attributions in the arid Tarim River Basin." The Journal of Agricultural Science 156, no. 3: 301-311.
Meltwater from glacierized catchments is one of the most important water supplies in central Asia. Therefore, the effects of climate change on glaciers and snow cover will have increasingly significant consequences for runoff. Hydrological modeling has become an indispensable research approach to water resources management in large glacierized river basins, but there is a lack of focus in the modeling of glacial discharge. This paper reviews the status of hydrological modeling in glacierized catchments of central Asia, discussing the limitations of the available models and extrapolating these to future challenges and directions. After reviewing recent efforts, we conclude that the main sources of uncertainty in assessing the regional hydrological impacts of climate change are the unreliable and incomplete data sets and the lack of understanding of the hydrological regimes of glacierized catchments of central Asia. Runoff trends indicate a complex response to changes in climate. For future variation of water resources, it is essential to quantify the responses of hydrologic processes to both climate change and shrinking glaciers in glacierized catchments, and scientific focus should be on reducing uncertainties linked to these processes.
Yaning Chen; Weihong Li; Gonghuan Fang; Zhi Li. Review article: Hydrological modeling in glacierized catchments of central Asia – status and challenges. Hydrology and Earth System Sciences 2017, 21, 669 -684.
AMA StyleYaning Chen, Weihong Li, Gonghuan Fang, Zhi Li. Review article: Hydrological modeling in glacierized catchments of central Asia – status and challenges. Hydrology and Earth System Sciences. 2017; 21 (2):669-684.
Chicago/Turabian StyleYaning Chen; Weihong Li; Gonghuan Fang; Zhi Li. 2017. "Review article: Hydrological modeling in glacierized catchments of central Asia – status and challenges." Hydrology and Earth System Sciences 21, no. 2: 669-684.
Glaciers are one of the most important water supplies of glacierized catchments in Central Asia. Therefore, the effects of climate change on glaciers, snow cover and permafrost will have increasingly significant consequences for runoff. Hydrological modeling has become an indispensable research approach to water resources management in large glacierized river basins, but there is a lack of focus in the modeling of glacial discharge. This paper reviews the status of hydrological modeling in glacierized catchments of Central Asia, discussing the limitations of the available models and extrapolating these to future challenges and directions. After reviewing recent efforts, we conclude that the main sources of uncertainty in assessing the regional hydrological impacts of climate change are the unreliable and incomplete datasets and the lack of understanding of the hydrological regimes of glacierized catchments of Central Asia. Runoff trends indicate a complex response of catchments to changes in climate. For future variation of water resources, it is essential to quantify the responses of hydrologic processes to both climate change and shrinking glaciers in glacierized catchments, and scientific focus should be on reducing these uncertainties.
Yaning Chen; Weihong Li; Gonghuan Fang; Zhi Li. Hydrological modeling in glacierized catchments of Central Asia: status and challenges. 2016, 2016, 1 -23.
AMA StyleYaning Chen, Weihong Li, Gonghuan Fang, Zhi Li. Hydrological modeling in glacierized catchments of Central Asia: status and challenges. . 2016; 2016 ():1-23.
Chicago/Turabian StyleYaning Chen; Weihong Li; Gonghuan Fang; Zhi Li. 2016. "Hydrological modeling in glacierized catchments of Central Asia: status and challenges." 2016, no. : 1-23.
The dramatic increase of global temperature since the year 2000 has a considerable impact on the global water cycle and vegetation dynamics. Little has been done about recent feedback of vegetation to climate in different parts of the world, and land evapotranspiration (ET) is the means of this feedback. Here we used the global 1 km MODIS net primary production (NPP) and ET data sets (2000–2014) to investigate their temporospatial changes under the context of global warming. The results showed that global NPP slightly increased in 2000–2014 at a rate of 0.06 PgC yr−2. More than 64 % of vegetated land in the Northern Hemisphere (NH) showed increased NPP (at a rate of 0.13 PgC yr−2), while 60.3 % of vegetated land in the Southern Hemisphere (SH) showed a decreasing trend (at a rate of −0.18 PgC yr−2). Vegetation greening and climate change promote rises of global ET. Specially, the increased rate of land ET in the NH (0.61 mm yr−2) is faster than that in the SH (0.41 mm yr−2). Over the same period, global warming and vegetation greening accelerate evaporation in soil moisture, thus reducing the amount of soil water storage. Continuation of these trends will likely exacerbate regional drought-induced disturbances and point to an increased risk of ecological drought, especially during regional dry climate phases.
Zhi Li; Yaning Chen; Yang Wang; Gonghuan Fang. Dynamic changes in terrestrial net primary production and their effects on evapotranspiration. Hydrology and Earth System Sciences 2016, 20, 2169 -2178.
AMA StyleZhi Li, Yaning Chen, Yang Wang, Gonghuan Fang. Dynamic changes in terrestrial net primary production and their effects on evapotranspiration. Hydrology and Earth System Sciences. 2016; 20 (6):2169-2178.
Chicago/Turabian StyleZhi Li; Yaning Chen; Yang Wang; Gonghuan Fang. 2016. "Dynamic changes in terrestrial net primary production and their effects on evapotranspiration." Hydrology and Earth System Sciences 20, no. 6: 2169-2178.
Earth experienced dramatic environmental changes in the recent 15 years (2000–2014). The past decade has been the warmest in the instrumental record, which significantly influences the global water cycle and vegetation activities. Overall, the global inter-annual series of net primary production (NPP) slightly increased in 2000–2014 at a rate of 0.06 PgC/yr2. More than 64 % of vegetated land in the Northern Hemisphere showed increased net primary production, while 60.3 % of vegetated land in the Southern Hemisphere showed decreased trend. Net primary production correlates positively with land actual evapotranspiration (ET), especially in the Northern Hemisphere, where the increased vegetation productivity (0.13 PgC/yr2) promotes decadal rises of terrestrial evapotranspiration (0.61 mm/yr2). However, anomalous dry conditions led to reduced vegetation productivity (−0.18 PgC/yr2) and nearly ceased growth in terrestrial evapotranspiration in the Southern Hemisphere (0.41 mm/yr2). Under the content of past warmest 15 years, global potential evapotranspiration (PET) shows an increasing trend of 1.72 mm/yr2, while precipitation for the domain shows a variability positive trend of 0.84 mm/yr2, which consistent with expected water cycle intensification. But precipitation trend is lower than evaporative demand, indicating some moisture deficit between available water demand and supply for evapotranspiration, thereby accelerated soil moisture loss. Drought indices and precipitation-minus-evaporation suggested an increased risk of drought in the present century. To understand why climates in the northern and southern hemispheres respond differently to NPP, the results showed that temperature is the dominant control on vegetation growth in the high latitude in the Northern Hemisphere, while net radiation is the main effect factors to NPP in the mid latitude, and in arid and semi-arid biomes also mainly driven by precipitation. While in the Southern Hemisphere, NPP decreased because of warming associated drying trends of PDSI.
Zhi Li; Yaning Chen; Yang Wang; Gonghuan Fang. Dynamic changes of terrestrial net primary production and its feedback to evapotranspiration. 2016, 2016, 1 -26.
AMA StyleZhi Li, Yaning Chen, Yang Wang, Gonghuan Fang. Dynamic changes of terrestrial net primary production and its feedback to evapotranspiration. . 2016; 2016 ():1-26.
Chicago/Turabian StyleZhi Li; Yaning Chen; Yang Wang; Gonghuan Fang. 2016. "Dynamic changes of terrestrial net primary production and its feedback to evapotranspiration." 2016, no. : 1-26.
To study the impact of future climatic changes on hydrology in the Kaidu River Basin in the Tianshan Mountains, two sets of future climatic data were used to force a well-calibrated hydrologic model: one is bias-corrected regional climate model (RCM) outputs for RCP4.5 and RCP8.5 future emission scenarios, and the other is simple climate change (SCC) with absolute temperature change of −1~6°C and relative precipitation change of −20%~60%. Results show the following: (1) temperature is likely to increase by 2.2°C and 4.6°C by the end of the 21st century under RCP4.5 and RCP8.5, respectively, while precipitation will increase by 2%~24%, with a significant rise in the dry season and small change in the wet season; (2) flow will change by −1%~20%, while evapotranspiration will increase by 2%~24%; (3) flow increases almost linearly with precipitation, while its response to temperature depends on the magnitude of temperature change and flow decrease is significant when temperature increase is greater than 2°C; (4) similar results were obtained for simulations with RCM outputs and with SCC for mild climate change conditions, while results were significantly different for intense climate change conditions.
Gonghuan Fang; Jing Yang; Yaning Chen; Shuhua Zhang; Haijun Deng; Haimeng Liu; Philippe De Maeyer. Climate Change Impact on the Hydrology of a Typical Watershed in the Tianshan Mountains. Advances in Meteorology 2015, 2015, 1 -10.
AMA StyleGonghuan Fang, Jing Yang, Yaning Chen, Shuhua Zhang, Haijun Deng, Haimeng Liu, Philippe De Maeyer. Climate Change Impact on the Hydrology of a Typical Watershed in the Tianshan Mountains. Advances in Meteorology. 2015; 2015 ():1-10.
Chicago/Turabian StyleGonghuan Fang; Jing Yang; Yaning Chen; Shuhua Zhang; Haijun Deng; Haimeng Liu; Philippe De Maeyer. 2015. "Climate Change Impact on the Hydrology of a Typical Watershed in the Tianshan Mountains." Advances in Meteorology 2015, no. : 1-10.