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The Three-River Source Region (TRSR), China's water tower and an important ecological barrier in China, provides a considerable amount of water to the downstream regions, home to more than 500 million people. The present study focused on the assessment of hydrological components (i.e., precipitation, actual evapotranspiration, potential evapotranspiration, surface flow, baseflow, streamflow, soil moisture, snowmelt water, and terrestrial water storage), their transformation and trends along with meteorological elements (i.e., maximum temperature, minimum temperature, mean temperature, relative humidity, wind speed, and sunshine hours) in the historical and future periods. For this, the hydrological model, HEC-HMS, was applied to simulate hydrological components and Mann-Kendal to explore the trends for 1981–2015. First time, the statistical downscaling model, SDSM, was used to generate climatic data under the shared socio-economic scenario-5 (SSP585) in the region, which was applied to simulate the hydrological cycle. The assessment results showed that precipitation transformed into evapotranspiration and streamflow by 70 % and 30 %, respectively. In the region, streamflow was generated by 78 %, 22 %, and 5.6 % by baseflow, surface flow, and snowmelt. According to trend results, all climatic variables showed statistically significant trends but insignificant in all hydrological components for the historical period, except evapotranspiration. However, all hydroclimatic components were projected to increase in the future, except windspeed. For example, temperature, precipitation, evapotranspiration, streamflow, and direct flow (surface flow) will increase by 1.4 (3.3) °C, 12 (36) %, 8.5 (19) %, 25 (95) %, and 77 (473) % in 2021–2060 (2061–2100) relative to 1981–2020, which shows, the region will be hotter and wetter, with high flooding potential in the future. These results will be helpful for precise water resources planning and management in this extremely sensitive region to climate change.

Corn leaf blight and stem rot caused by Colletotrichum graminicola are significant diseases that severely affect corn crops. Glycosyltransferases (GTs) catalyze the transfer of sugar residues to diverse receptor molecules, participating in numerous biological processes and facilitating functions ranging from structural support to signal transduction. This study identified 101 GT genes through functional annotation of the C. graminicola TZ–3 genome. Subsequent analyses revealed differences among the C. graminicola GT (CgGT) genes. Investigation into subcellular localization indicated diverse locations of CgGTs within subcellular structures, while the presence of multiple domains in CgGTs suggests their involvement in diverse fungal biological processes through versatile functions. The promoter regions of CgGT genes are enriched with diverse cis-acting regulatory elements linked to responses to biotic and abiotic stresses, suggesting a key involvement of CgGT genes in the organism’s multi-faceted stress responses. Expression pattern analysis reveals that most CgGT genes were differentially expressed during the interaction between C. graminicola and corn. Integrating gene ontology functional analysis revealed that CgGTs play important roles in the interaction between C. graminicola and corn. Our research contributes to understanding the functions of CgGT genes and investigating their involvement in fungal pathogenesis. At the same time, our research has laid a solid foundation for the development of sustainable agriculture and the utilization of GT genes to develop stress-resistant and high-yield crop varieties.

The Amudarya River (ADR) is the largest source of freshwater in Central Asia providing livelihood to millions of people by extracting water for agriculture. However, the over-exploitation has created some critical environmental issues. For example, almost no water for the delta and the Aral Sea, which was once the 4th largest lake in the world. The present study focused on the assessment of environmental flow requirements (E-flows) in the basin. However, the main challenges in the accomplishment were the unavailability of natural streamflow, which is necessary for E-flow assessment, and sparse and limited hydroclimatic data. A hydrologic model was configured to simulate naturalized streamflow using the meteorological data from the Climate Research Unit. Four hydrological methods (i.e., Tennant, low flow index (7Q10), flow duration curve analysis (Q90, and Q95), and flow duration curve shifting (FDCS)) and all-method mean were applied to estimate E-flows at 34 sites on all tributaries of the ADR. According to FDCS, 7Q10, Q90, and Q95, E-flows should be 46%, 37%, 30%, and 25% of naturalized mean annual flow (NMAF), respectively, and on average, it should be 35% of NMAF, assessed by the all-methods mean. For low-flow (October–March) and high-flow (April–September) months, E-flows were determined to be 20–30% and 40–98% of NMAF, respectively. E-flow evaluation with the current environmental conditions showed very serious concerns because no sites met the environmental flow requirements below Kerki. This study will be guidelines to improve the riverine ecosystem and for future sustainable development in the region.

Abstract In the industry, there is still a substantial amount of old in‐service equipment without a fault warning function. To provide an effective fault monitoring scheme for the in‐service motor drive system inside the equipment, this paper proposes a fault diagnosis method based on the DC‐link current at the power side, which can complete the fault monitoring task only outside the equipment without disassembly and assembly of the equipment and the inside installation of sensors. The effect of open‐circuit faults on DC‐link current is thoroughly examined and classified into four classes. To locate the faulty switching component of voltage‐source‐inverter (VSI), one electric period of DC‐link current is split into six regions according to the current vector position. And the relationship between current vector regions, fault signatures, and fault locations is summarized. Additionally, a low‐pass filter is used to smooth the DC‐link current and reduce the bandwidth limit of current sensors. Open circuit faults can be detected and located by identifying the fault signature in the DC‐link current and rotor position. Finally, the effectiveness and robustness of the proposed method are verified by experiment results.

With the increasing demand for high torque density in motors, more and more new topologies emerge. Furthermore, the magnetic field modulation principle is widely concerned and has evolved into an effective analysis method for studying the new motor topology. This paper introduces the principle of magnetic field modulation. And the research on high torque density in recent years is reviewed from the perspective of magnetic field modulation, including permanent magnet vernier machine (PMVM), flux reverse machine (FRM), flux switching machine (FSM), dual permanent magnet (DPM) machine, and DC biased machine. The principle of magnetic field modulation makes it possible to propose higher torque density topologies in the future.

Municipal water withdrawal (MWW) information is of great significance for water supply planning, including water supply pipeline networks planning, optimization and management. Currently most MWW data are reported as spatially aggregated over large-area survey regions or even lack of data, which is unable to meet the growing demand for spatially detailed data in many applications. In this paper, six different models are constructed and evaluated in estimating global MWW using aggregated MWW data and gridded raster covariates. Among the models, the artificial neural network-based indirect model (NNM) shows the best accuracy with higher R2 and lower NMAE and NRMSE in different spatial scales. The estimates achieved from the NNM model are consistent with census and survey data, and outperforms the existing global gridded MWW dataset. At last, the NNM model is applied to mapping global gridded MWW for the year 2015 at 0.1 × 0.1° resolution. The proposed method can be applied to a wider aggregated output learning problem and the high-resolution global gridded MWW data can be used in hydrological models and water resources management. HIGHLIGHTS Different models are constructed and evaluated in estimating gridded municipal water withdrawal.; Global fine-resolution municipal water withdrawal data are generated using aggregated data and an artificial neural network model.; Gridded indirect artificial neural network model through per capita municipal water withdrawal achieved better performance than other models.; Uncertainty analysis indicates the robustness of a gridded indirect artificial neural network model at regional scale.; The artificial neural network-based method can be applied to a broader aggregated output learning problem. ;

The paper presents an accurate analytical subdomain model for predicting the electromagnetic performance in the symmetrical dual three-phase surface-mounted permanent magnet synchronous machine (PMSM) under open-phase faulty conditions. The model derivations are extended from previous accurate subdomain models accounting for slotting effects. Compared with most conventional subdomain models for traditional three-phase machines with nonoverlapping winding arrangement, the subdomain model proposed in this paper applied for the 24-slot/4-pole dual three-phase machine with symmetrical overlapping winding arrangement. In order to investigate the postfault electromagnetic performance, the reconfigured phase currents and then current density distribution in stator slots under different open-circuit conditions are discussed. According to the developed model and postfault current density distribution, the steady-state electromagnetic performance, such as the electromagnetic torque and unbalanced magnetic force, under open-circuit faulty conditions are obtained. For validation purposes, finite element analysis (FEA) is employed to validate the analytical results. The result indicate that the postfault electromagnet performance can be accurately predicted by the proposed subdomain model, which is in good agreement with FEA results.

Offshore wind energy is an important part of clean energy, and the adoption of wind energy to generate electricity will contribute to the implementation of the carbon peaking and carbon neutrality goals. The combination of the fractional frequency transmission system (FFTS) and the direct-drive wind turbine generator will be beneficial to the development of the offshore wind power industry. The use of fractional frequency in FFTS is beneficial to the transmission of electrical energy, but it will also lead to an increase in the volume and weight of the generator, which is unfavorable for wind power generation. Improving the torque density of the generator can effectively reduce the volume of the generators. The vernier permanent magnet machine (VPM) operates on the magnetic flux modulation principle and has the merits of high torque density. In the field of electric machines, the vernier machine based on the principle of magnetic flux modulation has been proved its feasibility to reduce the volume and weight. However, in the field of low-speed direct-drive machines for high-power fractional frequency power generation, there are still few related researches. Therefore, this paper studies the application of magnetic flux modulation in fractional frequency and high-power direct-drive wind turbine generators, mainly analyzes the influence of different pole ratios and different pole pairs on the generator, and draws some conclusions to provide reference for the design of wind turbine generators.

Land surface net radiation flux （Rn） is an important parameter of energy and water exchange processes in land-atmosphere interactions.Accurate estimation of spatial-temporal characteristics of Rn is useful in a wide range of applications， such as hydrology， meteorology， ecology and agriculture.In this paper， we presented a framework to estimate instantaneous and daytime Rn under all sky conditions by using MODIS products from 2011 to 2019 in Qinghai Province.The accuracy of instantaneous and daytime Rn estimation was verified by using the radiation flux observations in Xining and Golmud and FAO-56-based estimation across 50 meteorological stations， respectively.The results showed that the root mean square error （RMSE） of instantaneous and daytime Rn estimated under clear sky conditions in Xining station， in comparison of ground-based measurements was 72.35 W·m-2 and 2.29 MJ·m-2， respectively.However， significant overestimates were observed in Golmud station with Bias of 133.19 W·m-2 and 3.25 MJ·m-2.Judging from daytime Rn， there was a good agreement between FAO-56-based estimation and our estimation with a RMSE of 2.04 MJ·m-2 across 50 meteorological stations.In terms of the monthly and seasonal variations of Rn in Qinghai Province， the annual average value was 4176.62 MJ·m-2， and its monthly variation showed a single peak distribution， with the maximum and minimum values in June （559.23 MJ·m-2） and December （134.68 MJ·m-2）， respectively.The annual variation of Rn presented a fluctuant decreasing trend from 2011 to 2019， and significantly decreased about 1.16% from 2012 to 2013， probably due to climate change and human activity.For example， Rn decreased with increasing land surface temperature and decreasing fractional vegetation cover from 2012 to 2016.In Qinghai Province， the regions with larger Rn were mainly located in the southeast， while regions with lower Rn were mainly located in the northwest.The spatial distribution characteristics of Rn had significant relation to various factors， including altitude， surface albedo and fractional vegetation cover.Specifically， there was a good positive correlation between the spatial distribution characteristics of altitude and that of Rn in Qinghai Province.In consideration of the similar overestimation in FAO-56-based Rn， the overestimation of instantaneous and daytime Rn in Golmud station may result from the original error of radiation flux observations.Compared with results in clear sky， the accuracy of daytime Rn estimation was lower under cloudy sky conditions （RMSE=4.37 MJ·m-2）.The accuracy of monthly and annual mean Rn， however， had better accuracy with the RMSE of 42.59 MJ/m2 and 266.35 MJ·m-2.There are mainly three possible reasons of low accuracy in cloudy sky， including the error of applying data and model under cloudy conditions， the mismatch of remote sensing data and ground observation data in temporal and spatial scales， the effect of clouds on estimation accuracy of daytime Rn in the time scale expansion of instantaneous Rn.

A predominantly mountainous country Nepal has a complex climatic pattern that varies from tropical in the south (Terai region) to arctic in the north (Himalayas). The gradual rise in temperature in the mountainous region has attracted great interest among the scientific community in general over recent years. However, recent warming in Nepal’s east-west and south-north temperature gradients and its implications for ecology and society based on facts and figures are still lacking. In this context, temperature data (1970–2016) of 76 meteorological stations from the Terai region to the Mountains were used in this study to analyze the annual and seasonal warming trends in the different physiographic regions of Nepal. We performed a hybrid analytical approach i.e. integrated statistical and theoretical tools to detect the warming trend and its ecological and societal implications across the country. The Eastern part of the country was found to be more warming than the Central and Western parts, showing an increased climatic sensitivity across the Khumbu (Mt. Everest region). The increasing trends of temperature have been found in all physiographic regions along an altitude gradient, i.e. Terai, Siwaliks, Lower Hills, and Upper Hills observed 0.15, 0.26, 0.68, and 0.57 °C per decade, respectively. Higher warming trend in Lower Hills than the Upper Hills showed that higher elevations experienced lesser degrees of warming trends than the lower elevations in the mountainous regions. Further, a higher warming trend was observed in the winter season than the other seasons in all regions except for Terai. Based on the warming trends in different physiographic regions, we also found a similar pattern of ecological impacts, where a higher warming region also experienced higher ecological impacts such as changes in water resources, phenology, etc. Lower Hills, Upper Hills, and Mountains experienced higher adverse impacts than the Terai and Siwaliks in the current global warming scenarios.

With abundant resources in the wetland, the Yellow River Delta provides important habitats for various kinds of rare bird species. However, due to climate change and human water withdrawal activities, no-flow events of the Yellow River occurred frequently since the 1970s, resulting in serious wetland degradation and biodiversity losses. Ecological water supplement has been regarded as one of the most effective measures to cope with these environmental problems. Accordingly, how much water is required for the ecological restoration becomes an essential question to be answered. Since the primary function of the Yellow River Delta Natural Reserve (YRDNR), the typical wetland in the Yellow River Delta, is to provide suitable habitats for various rare birds, the purpose of this paper is to propose a method based on water balance analysis to specify monthly ecological water supplement for the habitats of typical birds in the YRDNR. Specifically, three typical birds were selected as the protection objects, including Grus japonensis, Ciconia boyciana, and Larus saundersi. Monthly water supplement was determined by monthly long-term time series data (2003–2018) of evapotranspiration product derived from remote sensing and meteorological data (precipitation and pan evaporation) acquired from National Meteorological Information Center. The results showed that the annual ecological water supplement for 10 km2 ideal habitats was 666.17×104 m3, 1165.22×104 m3, and 664.48×104 m3 for G. japonensis, C. boyciana, and L. saundersi, respectively. Besides, it was found that annual precipitation generally had a significant negative relation with annual ecological water supplement, which suggested that local precipitation should be considered as a key factor in determining the amount of annual water supplement. The frequency analysis was then implemented to provide reasonable scheme of actual ecological water supplement under different precipitation scenarios. The results indicated that annual ecological water supplement for the whole YRDNR was 1.81×108 m3, 1.94×108 m3, 2.10×108 m3 and 2.25×108 m3 respectively under wet, average, dry and extreme dry conditions. If water storage measurements are implemented to store surplus precipitation under rainy season, the average volume would reduce by nearly 10%.

Multiphase machines have been attracting more and more attentions in high-reliability-required applications due to their inherent fault-tolerant capability. Postfault control strategies with-standing open-circuit faults (OCFs) for several multiphase machine types, like five-phase, symmetrical six-phase (S6) and asymmetrical six-phase (A6) machines, have been widely investigated in recent literatures. However, fault-tolerant control for symmetrical dual three-phase (D3) machines have rarely been studied so far. To fill the gap, this paper addresses key issues in postfault decoupling modeling and field orient control (FOC) for the dual three-phase surface-mounted permanent magnet synchronous machine (SPMSM) with isolated neutrals under single-phase OCF. To do so, a postfault decoupling model with reduced-order transformation is established for D3 machines. Postfault current references are reconfigured with two main-stream criteria: minimum-loss (ML) and maximum-torque (MT). Furthermore, third harmonic flux linkage/back-EMF are taken into account in modeling and control, since it causes third harmonic currents and hence torque ripples under single-phase OCF. Proportional-resonant controllers are employed to decrease the third harmonic currents and torque pulsations. The validity of the postfault control strategies is proved by experiments.

Abstract Recently, Goji berry (Lycium barbarum L.) has been extensively cultivated to improve the fragile ecological environment and increase the income of residents in Qinghai Province, northwestern China. However, few studies have focused on the physiological responses of Goji berry under salt stress and alkali stress. Gas exchange, photosynthetic pigments, and chlorophyll fluorescence were evaluated in response to neutral (NaCl) and alkali (NaHCO3) salt stresses. Nine irrigation treatments were applied over 30 days and included 0(Control group), 50, 100, 200, and 300 mM NaCl and NaHCO3. The results showed that salt and alkali stress reduced all the indicators and that alkali stress was more harmful to Goji berry than salt stress under the same solution concentrations. The salt tolerance and alkali resistance thresholds were identified when the index value exceeded the 50% standard of the control group, and threshold values of 246.3 ± 2.9 mM and 108.4.7 ± 2.1 mM, respectively, were determined by regression analysis. These results were used to identify the optimal water content for Goji berry. The minimum soil water content to cultivate Goji berry should be 16.22% and 23.37% under mild and moderate salt stress soils, respectively, and 29.10% and 42.68% under mild and moderate alkali stress soil, respectively.

Lake Chad is one of the largest lakes in the world, but extremely vulnerable to the changing climate and human activities in the basin. The Lake Chad basin is one of the largest endorheic basins in the world and straddles the borders of Central African Republic, Chad, Libya, Niger, Nigeria, Algeria, Cameroon, and Sudan. In the last 40–50 years, the lake has shrunk from a surface area of 25,000 km2 to 2000 km2. However, the availability and quality of hydro-climatic data for researchers are major barriers to research. Since observed station data is highly sparse in the basin and difficult to collect, monthly climatic data was extracted from the gridded Climate Research Unit (CRU) dataset. The gridded CRU temperature and rainfall data was extracted at 81 points, and monthly temperature and rainfall data was converted into daily data for hydrologic modelling in Mahmood and Jia [1]. This data article also includes observed streamflow data of 3 hydrometric stations and rainfall data of 11 stations, which was obtained from the Lake Chad Basin Commission. Natural streamflow data simulated with hydrologic model at N'Djamena station on the Chari-Logone River is also included in this data article. Keywords: The Lake Chad basin, Observed climate data, Observed streamflow, Natural streamflow, The CRU climatic data, Daily generated climate data

The present study investigated future temporal and spatial changes in maximum temperature, minimum temperature, and precipitation in two sub-basins of the Jhelum River basin—the Two Peak Precipitation basin (TPPB) and the One Peak Precipitation basin (OPPB)—and in the Jhelum River basin on the whole, using the statistical downscaling model, SDSM. The Jhelum River is one of the biggest tributaries of the Indus River basin and the main source of water for Mangla reservoir, the second biggest reservoir in Pakistan. An advanced interpolation method, kriging, was used to explore the spatial variations in the study area. Validation results showed a better relationship between simulated and observed monthly time series as well as between seasonal time series relative to daily time series, with an average R2 of 0.92–0.97 for temperature and 0.22–0.62 for precipitation. Mean annual temperature was projected to rise significantly in the entire basin under two emission scenarios of HadCM3 (A2 and B2). However, these changes in mean annual temperature were predicted to be higher in the TPPB than the OPPB. On the other hand, mean annual precipitation showed a distinct increase in the TPPB and a decrease in the OPPB under both scenarios. In the case of seasonal changes, spring in the TPPB and autumn in the OPPB were projected to be the most affected seasons, with an average increase in temperature of 0.43–1.7 °C in both seasons relative to baseline period. Summer in the TPPB and autumn in the OPPB were projected to receive more precipitation, with an average increase of 4–9% in both seasons, and winter in the TPPB and spring in the OPPB were predicted to receive 2–11% less rainfall under both future scenarios, relative to the baseline period. In the case of spatial changes, some patches of the basin showed a decrease in temperature but most areas of the basin showed an increase. During the 2020s (2011–2040), about half of the basin showed a decrease in precipitation. However, in the 2080s (2071–2099), most parts of the basin were projected to have decreased precipitation under both scenarios.

We assessed the present and future climatologies of mean summer monsoon over South Asia using a high resolution regional climate model (RegCM4) with a 25 km horizontal resolution. In order to evaluate the performance of the RegCM4 for the reference period (1976–2005) and for the far future (2070–2099), climate change projections under two greenhouse gas representative concentration pathways (RCP4.5 and RCP8.5) were made, the lateral boundary conditions being provided by the geophysical fluid dynamic laboratory global model (GFDL-ESM2M). The regional climate model (RCM) improves the simulation of seasonal mean temperature and precipitation patterns compared to driving global climate model (GCM) during present-day climate conditions. The regional characteristic features of South Asian summer monsoon (SASM), like the low level jet stream and westerly flow over the northern the Arabian Sea, are well captured by the RegCM4. In spite of some discrepancies, the RegCM4 could simulate the Tibetan anticyclone and the direction of the tropical easterly jet reasonably well at 200 hPa. The projected temperature changes in 2070–2099 relative to 1976–2005 for GFDL-ESM2M show increased warming compared to RegCM4. The projected patterns at the end of 21st century shows an increase in precipitation over the Indian Peninsula and the Western Ghats. The possibilities of excessive precipitation include increased southwesterly flow in the wet period and the effect of model bias on climate change. However, the spatial patterns of precipitation are decreased in intensity and magnitude as the monsoon approaches the foothills of the Himalayas. The RegCM4-projected dry conditions over northeastern India are possibly related to the anomalous anticyclonic circulations in both scenarios.

Using National Oceanographic and Atmospheric Administration/Advanced Very High Resolution Radiometer (NOAA/AVHRR) and Climatic Research Unit (CRU) climate datasets, we analyzed interannual trends in the growing-season Normalized Difference Vegetation Index (NDVI) in China from 1982 to 2011, as well as the effects of climatic variables and human activities on vegetation variation. Growing-season (period between the onset and end of plant growth) NDVI significantly increased (p < 0.01) on a national scale and showed positive trends in 52.76% of the study area. A multiple regression model was used to investigate the response of vegetation to climatic factors during recent and previous time intervals. The interactions between growing-season NDVI and climatic variables were more complex than expected, and a lag existed between climatic factors and their effects on NDVI. The regression residuals were used to show that over 6% of the study area experienced significantly human-induced vegetation variations (p < 0.05). These regions were mostly located in densely populated, reclaimed agriculture, afforestation, and conservation areas. Similar conclusions were drawn based on land-use change over the study period.

The knowledge of water storage variations in ungauged lakes is of fundamental importance to understanding the water balance on the Tibetan Plateau. In this paper, a simple framework was presented to monitor the fluctuation of inland water bodies by the combination of satellite altimetry measurements and optical satellite imagery without any in situ measurements. The fluctuation of water level, surface area, and water storage variations in Lake Qinghai were estimated to demonstrate this framework. Water levels retrieved from ICESat (Ice, Cloud, and and Elevation Satellite) elevation data and lake surface area derived from MODIS (Moderate Resolution Imaging Spectroradiometer) product were fitted by linear regression during the period from 2003 to 2009 when the overpass time for both of them was coincident. Based on this relationship, the time series of water levels from 1999 to 2002 were extended by using the water surface area extracted from Landsat TM/ETM+ images as inputs, and finally the variations of water volume in Lake Qinghai were estimated from 1999 to 2009. The overall errors of water levels retrieved by the simple method in our work were comparable with other globally available test results with r = 0.93, MAE = 0.07 m, and RMSE = 0.09 m. The annual average rate of increase was 0.11 m/yr, which was very close to the results obtained from in situ measurements. High accuracy was obtained in the estimation of surface areas. The MAE and RMSE were only 6 km2, and 8 km2, respectively, which were even lower than the MAE and RMAE of surface area extracted from Landsat TM images. The estimated water volume variations effectively captured the trend of annual variation of Lake Qinghai. Good agreement was achieved between the estimated and measured water volume variations with MAE = 0.4 billion m3, and RMSE = 0.5 billion m3, which only account for 0.7% of the total water volume of Lake Qinghai. This study demonstrates that it is feasible to monitor comprehensively the fluctuation of large water bodies based entirely on remote sensing data.

In this study, a linear scaling method, precipitation extended linear scaling (PELS), is proposed to correct precipitation simulated by GCMs. In this method, monthly scaling factors were extended to daily scaling factors (DSFs) to improve the daily variation in precipitation. In addition, DSFs were also checked for outliers and smoothed with a smoothing filter to reduce the effect of noisy DSFs before correcting the GCM’s precipitation. This method was evaluated using the observed precipitation of 21 climate stations and five GCMs in the Jhelum River basin, Pakistan and India, for the period of 1986–2000 and also compared with the original linear scaling (OLS) method. The evaluation results showed substantial improvement in the corrected GCM precipitation, especially in case of mean and standard deviation values. Although PELS and OLS showed comparable results, the overall performance of PELS was better than OLS. After Evaluation, PELS was applied to the future precipitation from five GCMs for the period of 2041–2070 under RCP8.5 and RCP2.6 in the Jhelum basin, and the future changes in precipitation were calculated with respect to 1971–2000. According to average all GCMs, annual precipitation was projected to decrease by 4% and 6% in the basin under RCP8.5 and RCP2.6, respectively. Although two seasons, spring and fall, showed some increasing precipitation, the monsoon season showed severe decrease in precipitation, with 22% (RCP8.5) and 29% (RCP2.6), and even more reduction in July and August, up to 34% (RCP8.5) and 36% (RCP2.6). This means if the climate of the world follows the RCP8.5 and RCP2.6, then there will be a severe reduction in precipitation in the Jhelum basin during peak months. It was also observed that decline in precipitation was higher under RCP2.6 than RCP8.5.

The drought episodes in the second half of the 20th century have profoundly modified the state of Lake Chad and investigation of its variations is necessary under the new circumstances. Multiple remote sensing observations were used in this paper to study its variation in the recent 25 years. Unlike previous studies, only the southern pool of Lake Chad (SPLC) was selected as our study area, because it is the only permanent open water area after the serious lake recession in 1973–1975. Four satellite altimetry products were used for water level retrieval and 904 Landsat TM/ETM+ images were used for lake surface area extraction. Based on the water level (L) and surface area (A) retrieved (with coinciding dates), linear regression method was used to retrieve the SPLC’s L-A curve, which was then integrated to estimate water volume variations ( Δ V ). The results show that the SPLC has been in a relatively stable phase, with a slight increasing trend from 1992 to 2016. On annual average scale, the increase rate of water level, surface area and water volume is 0.5 cm year−1, 0.14 km2 year−1 and 0.007 km3 year−1, respectively. As for the intra-annual variations of the SPLC, the seasonal variation amplitude of water level, lake area and water volume is 1.38 m, 38.08 km2 and 2.00 km3, respectively. The scatterplots between precipitation and Δ V indicate that there is a time lag of about one to two months in the response of water volume variations to precipitation, which makes it possible for us to predict Δ V . The water balance of the SPLC is significantly different from that of the entire Lake Chad. While evaporation accounts for 96% of the lake’s total water losses, only 16% of the SPLC’s losses are consumed by evaporation, with the other 84% offset by outflow.

In this study, a new parameterization scheme of evaporative fraction (EF) was developed from the contextual information of remotely sensed radiative surface temperature ( T s ) and vegetation index (VI). In the traditional T s − V I triangle methods, the Priestley-Taylor parameter ∅ of each pixel was interpolated for each VI interval; in our proposed new parameterization scheme (NPS), it was performed for each isopiestic line of soil surface moisture. Specifically, ∅ of mixed pixels was determined as the weighted-average value of bare soil ∅ and full-cover vegetation ∅ . The maximum T s of bare soil ( T s m a x ) is the sole parameter needed as the constraint of the dry edge. This has not only bypassed the task involved in the determination of the maximum T s of fully vegetated surface ( T c m a x ), but also made it possible to reduce the reliance of the T s − V I triangle methods on the determination of the dry edge. Ground-based measurements taken during 21 days in 2004 were used to validate the EF retrievals. Results show that the accuracy achieved by the NPS is comparable to that achieved by the traditional T s − V I triangle methods. Therefore, the simplicity of the proposed new parameterization scheme does not compromise its accuracy in monitoring EF.

Aqueous zinc-ion batteries (ZIBs) offer numerous advantages, such as high energy density, enhanced safety, and low cost, making them an ideal choice for energy storage and conversion applications in the “postlithium” era. Hydrogel electrolytes, as the key component of flexible ZIBs, combine the ionic conductivity of traditional water electrolytes with the dimensional stability of solid polymer electrolytes. However, it remains a challenge to design comprehensive and appropriate hydrogel electrolytes to provide flexible ZIBs with good reversibility and versatility. This review discusses the engineering design of hydrogel electrolytes required for flexible ZIBs from the viewpoint of an electrolyte designer. The basic properties of the hydrogel electrolytes, zinc anodes, cathodes and electrolyte stabilization effects are described in detail. Furthermore, we explore the various challenges faced by hydrogel electrolytes and propose corresponding strategies. Finally, the review offers insights into the future development of hydrogel-stabilized ZIBs. [ABSTRACT FROM AUTHOR]

With the growing demand for scalable and cost-effective electrochemical energy storage systems, aqueous Zn-ion batteries (ZIBs) have attracted attention as cheap, efficient, and safe energy storage devices. However, practical applications of ZIBs are hampered by some challenges, such as Zn dendrite growth, corrosion, passivation, byproducts, cathodic dissolution, and harmful electrostatic interactions. These problems are directly associated with the electrolytes of ZIBs, which are in contact with both the cathode and anode. Recently, several studies have been conducted to optimize ZIB electrolytes. The electrolyte system includes the electrolyte and solvent. The solvent ensures stable operation of the electrolyte and improves the electrochemical efficiency of the cathode and anode, thus improving the electrochemical performance and stability of ZIBs. However, to date, the effect of solvents on the stability of Zn anodes remains unclear. Therefore, there is a need for detailed studies on solvents for ZIB electrolytes. Herein, we review the research progress in the stabilization of Zn anodes using various solvents, including alcohols, amines, acetonitrile, lipids, ethers, and dimethyl sulfoxide. In addition, we discuss the effects of different solvents on the stabilization mechanism of Zn anodes. Finally, the challenges and prospects of solvents used for stabilizing Zn anodes in electrolytes are analyzed, and future research directions for ZIB electrolyte dissolution are proposed. [ABSTRACT FROM AUTHOR]