Climate variability and trends at a national scale

Neonicotinoid metabolites in farmland surface soils in China based on multiple agricultural influencing factors: A national survey

Certain neonicotinoid metabolites (mNEOs) are causing widespread concern because they are equally or even more toxic than the parent NEOs. Currently, there is limited information on the distribution of mNEOs in soil. Especially, it is unknown that the effects of agricultural factors, such as plastic filming, plowing, irrigation, and fertilization, on mNEOs. This study is the first to reveal that mNEOs were commonly found in agricultural topsoil in China, with a geometric mean concentration of ΣmNEOs of 0.298 μg/kg. Among 31 provinces in Mainland China, Fujian had the highest mNEO residues, whereas Shanghai had the lowest. Among topsoil of various crop types, that of fruits and vegetables were found the highest mNEO residues. Furthermore, higher levels of film cover were associated with higher mNEO residues. Microplastics (MPs, serving as contaminant carriers) were positively correlated with mNEOs under field conditions, which was related to the adsorption capacity of microplastics and its influence on the soil conditions and the years of film cover. Alternatively, this study shows for the first time that irrigation water and manure might be sources of mNEO input into the soil, and that the plowing frequency might also influence on mNEOs.

Microbial co-occurrence network demonstrates spatial and climatic trends for global soil diversity

Despite recent research efforts to explore the co-occurrence patterns of diverse microbes within soil microbial communities, a substantial knowledge-gap persists regarding global climate influences on soil microbiota behaviour. Comprehending co-occurrence patterns within distinct geoclimatic groups is pivotal for unravelling the ecological structure of microbial communities, that are crucial for preserving ecosystem functions and services. Our study addresses this gap by examining global climatic patterns of microbial diversity. Using data from the Earth Microbiome Project, we analyse a meta-community co-occurrence network for bacterial communities. This method unveils substantial shifts in topological features, highlighting regional and climatic trends. Arid, Polar, and Tropical zones show lower diversity but maintain denser networks, whereas Temperate and Cold zones display higher diversity alongside more modular networks. Furthermore, it identifies significant co-occurrence patterns across diverse climatic regions. Central taxa associated with different climates are pinpointed, highlighting climate's pivotal role in community structure. In conclusion, our study identifies significant correlations between microbial interactions in diverse climatic regions, contributing valuable insights into the intricate dynamics of soil microbiota.

Distribution characteristics and risk assessment of neonicotinoid insecticides in planting soils of mainland China

Neonicotinoid insecticides (NEOs) are generally used in crop production. Their widespread use on agricultural soil has raised concerns regarding their health and ecological risks. Previous studies have reported the contamination of the farmland soils with NEOs from the coastal provinces of China. Information about NEOs at the national scale as well as the residues of their metabolites are relatively unknown. In this study, 391 soil samples were collected from 31 provinces in nine agricultural regions across mainland China, and the concentrations of ten parent NEOs and three metabolites were determined. At least one NEO was detected in all soil samples, with the sum of the NEOs (ΣNEOs) ranging from 0.04 to 702 μg/kg. The most common parent NEO and metabolite are imidacloprid and imidacloprid-urea, respectively. The concentrations of NEOs in coastal regions at the same latitude were higher than those in inland regions. The NEOs were further compared in the soils of seven types of monocrops and three types of multiple crops (multicrops) (i.e., two types of crops were produced in succession or simultaneously within the decade of this study). The results showed that the highest NEO residues were found in soils planted with vegetables (VE), fruits (FR), and cotton (CO) monocrops and VE & FR multicrops. Differences in NEO concentrations were observed between soils planted with monocrops and multicrops. For example, VE & FR > VE > vegetables and grains (VE & GR) > GR. Moreover, the health risks posed by NEOs in agricultural soils in China are extremely low, and the ecological risks require urgent attention. Particularly, individual NEOs in > 45% of agricultural soils in mainland China may have sublethal effects on two non-target species (HQnon-target > 0.01).

Sub-regional variation in atmospheric and land variables regulates tea yield in the Dooars region of West Bengal, India

Climatic variables can have localized variations within a region and these localized climate patterns can have significant effect on production of climate-sensitive crops such as tea. Even though tea cultivation and industries significantly contribute to employment generation and foreign earnings of several South Asian nations including India, sub-regional differences in the effects of climatic and soil variables on tea yield have remained unexplored since past studies focused on a tea-producing region as a whole and did not account for local agro-climatic conditions. Here, using a garden-level panel dataset based on tea gardens of Dooars region, a prominent tea-producing region in India, we explored how sub-regional variations in climatic and land variables might differently affect tea yield within a tea-producing region. Our analysis showed that the Dooars region harboured significant spatial variability for different climatic (temperature, precipitation, surface solar radiation) and soil temperature variables. Using graph-based Louvain clustering of tea gardens, we identified four spatial sub-regions which varied in terms of topography, annual and seasonal distribution of climatic and land variables and tea yield. Our sub-region-specific panel regression analyses revealed differential effects of climatic and land variables on tea yield of different sub-regions. Finally, for different emission scenario, we also projected future (2025-2100) tea yield in each sub-region based on predictions of climatic variables from three GCMs (MIROC5, CCSM4 and CESM1(CAM5)). A large variation in future seasonal production changes was projected across sub-regions (-23.4-35.7% changes in premonsoon, -4.2-3.1% changes in monsoon and -10.9-10.7% changes in postmonsoon tea production, respectively).

Frequency of osteoporosis in Chinese patients with rheumatoid arthritis: a meta-analysis

OBJECTIVE

To evaluate the current frequency of osteoporosis (OP) in Chinese patients with rheumatoid arthritis (RA) through meta-analysis.

METHODS

The databases of PubMed, Web of Science, Cochrane Library, CNKI, Wan Fang, CBM, and VIP were searched for relevant literature regarding the occurrence of OP in Chinese patients with RA from January 1, 2000, to September 15, 2022. The literature was screened using inclusion and exclusion criteria, and qualifying articles were subjected to data extraction, quality evaluation, and meta-analysis using Stata 17.0 software.

RESULTS

Altogether, 44 publications were included in this study, with a total sample size of 12,264 RA cases and 4532 patients with OP. Meta-analysis revealed that the frequency of OP in patients with RA was 37.67% [95% CI: 34.38%, 40.97%], while subgroup analysis showed that the frequency in South China was 49.43% [95% CI: 40.53%, 58.32%]. Also, the frequency in men was 29.29% [95% CI: 22.42%, 36.16%], which was significantly lower than in women (41.89% [95% CI: 36.87%, 46.90%]). The incidence rate in pre-menopausal women was only 15.19% [95% CI: 8.79%, 21.59%], much lower than the figure of 54.29% [95% CI: 45.28%, 63.30%] for post-menopausal women. Additionally, the frequency rates in the low, intermediate, and high disease activity groups were 24.52% [95% CI: 11.52%, 37.52%)], 27.67% [95% CI: 13.50%, 41.85%], and 57.96% [95% CI: 37.35%, 78.56%], respectively.

CONCLUSION

The frequency of OP in the Chinese RA population is higher than the world average, and patients with RA should receive standardized anti-RA therapy at an early stage, with emphasis on bone health in postmenopausal women, patients with high disease activity or longer disease duration.

Spatial-temporal variations of reference evapotranspiration and its driving factors in cold regions, northeast China

Reference evapotranspiration ([Formula: see text]) is an important indicator for hydrometeorological change, which integrates atmospheric and surface conditions, and its downward trends have been reported in many regions over the past several decades. Cold regions constitute an important ecological barrier in China; however, few studies focus on change in [Formula: see text] in cold regions. Especially in the cold region of northeast China (CRNEC), as one of the national strategic grain bases, understanding spatial-temporal variations of [Formula: see text] is important for agriculture water management and ecological protection. This study selected the observations at 113 national meteorological stations located in CRNEC and evaluated the trends of [Formula: see text] and their driving factors from 1961 to 2017. Results indicate that annual [Formula: see text] increases from the northeast to the southwest of CRNEC and has an insignificant decreasing trend in the whole study period, in which 33 stations (29.2%) show significant decreasing trends and only 19 stations (16.8%) show significant increasing trends at the 95% confidence level. An abrupt change in [Formula: see text] data is detected from 1994. Reasons for this abrupt change in [Formula: see text] vary largely over the study areas. Analysis shows that wind speed and minimum air temperature are the two major factors that control the change of [Formula: see text] before 1994. It also shows that wind speed and actual vapor pressure are the two major controlling factors after 1994. We also found that [Formula: see text] shows a certain correlation with Pacific Decadal Oscillation and Western Pacific Index, but there is a significant correlation between meteorological factors and teleconnection factors related to [Formula: see text]. These findings will promote agricultural water management and improve water ecological protection in the CRNEC. We investigated changes in reference evapotranspiration relationships with atmospheric circulation and its attributions over the cold regions in northeast China during 1961 ~ 2017. The results indicate that the wind speed and minimum air temperature are the two major factors that control the change of ET0 before 1994, and wind speed and actual vapor pressure are the two major controlling factors after 1994. We also found that ET0 shows a certain correlation with Western Pacific Index in the whole period.

Geo-Hydrological Events and Temporal Trends in CAPE and TCWV over the Main Cities Facing the Mediterranean Sea in the Period 1979–2018

The Mediterranean region is regarded as the meeting point between Europe, Africa and the Middle East. Due to favourable climatic conditions, many civilizations have flourished here. Approximately, about half a billion people live in the Mediterranean region, which provides a key passage for trading between Europe and Asia. Belonging to the middle latitude zone, this region experiences high meteorological variability that is mostly induced by contrasting hot and cold air masses that generally come from the west. Due to such phenomenon, this region is subject to frequent intensive precipitation events. Besides, in this complex physiographic and orographic region, human activities have contributed to enhance the geo-hydrologic risk. Further, in terms of climate change, the Mediterranean is a hot spot, probably exposing it to future damaging events. In this framework, this research focuses on the analysis of precipitation related events recorded in the EM–DAT disasters database for the period 1979–2018. An increasing trend emerges in both event records and related deaths. Then a possible linkage with two meteorological variables was investigated. Significant trends were studied for CAPE (Convective Available Potential Energy) and TCWV (Total Column Water Vapor) data, as monthly means in 100 km2 cells for 18 major cities facing the Mediterranean Sea. The Mann–Kendall trend test, Sen’s slope estimation and the Hurst exponent estimation for the investigation of persistency in time series were applied. The research provides new evidence and quantification for the increasing trend of climate related disasters at the Mediterranean scale: recorded events in 1999–2018 are about four times the ones in 1979–1998. Besides, it relates this rise with the trend of two meteorological variables associated with high intensity precipitation events, which shows a statistically significative increasing trend in many of the analysed cities facing the Mediterranean Sea.

Vegetation Dynamics and Climatological Drivers in Ethiopia at the Turn of the Century

Global change, particularly climate change, poses a risk of altering vegetation composition and health. The consequences manifest throughout Earth’s system as a change in ecosystem services and socioecological stability. It is therefore critical that vegetation dynamics are monitored to establish baseline conditions and detect shifts. Africa is at high risk of environmental change, yet evaluation of the link between climate and vegetation is still needed for some regions. This work expands on more frequent local and multinational scale studies of vegetation trends by quantifying directional persistence (DP) at a national scale for Ethiopia, based on the normalized difference vegetation index (NDVI) between 2000 and 2016. The DP metric determines cumulative change in vegetation greenness and has been applied to studies of ecological stability and health. Secondary analysis utilizing panel regression methodologies is carried out to measure the effect of climate on NDVI. Models are developed to consider spatial dependence by including fixed effects and spatial weights. Results indicate widespread cumulative declines in NDVI, with the greatest change during the dry season and concentrated in northern Ethiopia. Regression analyses suggest significant control from climatic variables. However, temperature has a larger effect on NDVI, which contrasts with findings of some previous studies.

A Win–Win Scenario for Agricultural Green Development and Farmers’ Agricultural Income: An Empirical Analysis Based on the EKC Hypothesis

Due to severe resource and environmental constraints, agricultural green development is a vital step for the low-carbon development of China. How to achieve the goal of a win–win scenario that simultaneously improves agricultural green total factor productivity (GTFP) and farmers’ agricultural income was the main focus of this study. Based on the panel dataset for 31 provinces in China from 2000 to 2018, this study calculated the agricultural GTFP using the global Malmquist–Luenberger (GML) index to measure the green development of agriculture. Furthermore, this study investigated the relationship between the agricultural GTFP and agricultural income in an environmental Kuznets curve (EKC) framework, together with the key factors affecting agricultural GTFP. The main results show that, first, driven by technical progress, the agricultural GTFP gradually increased across the country, while there existed a certain degree of heterogeneity in the growth of different regions. Second, the relationships between the agricultural GTFP and agricultural income exhibited a significant U-shape for the whole country and the four regions, indicating that a win–win scenario can be achieved between green development and income level. Third, industrialization and urbanization negatively affected agricultural GTFP, capital deepening played a positive role, and due to the mediated effect of capital deepening, the outflow of the agricultural labor force did not cause substantial harm to agricultural GTFP. The findings of our study provide useful policy implications for the promotion and development of agriculture in China.

Trends in Varietal Diversity of Main Staple Crops in Asia and Africa and Implications for Sustainable Food Systems

Crop species and varietal diversity on farm have the potential to trigger multiple regulating and provisioning ecosystem services. The latter is commonly assessed through targeted studies covering a select number of geographies and crop species, precluding comparisons across crops and at scale. This study draws on a large dataset on the varietal release dynamics for 11 major food crops in 44 countries of Asia and Africa to assess trends in diversity across crops and regions with a 50-year perspective. Our results show an increasing reduction of crop varietal diversity linked to the spatial displacement of traditional landraces. This trend occurs at a faster rate in Asia than in Africa. So-called mega varieties tend to increasingly dominate agricultural landscapes, adding to spatial homogeneity. We further found a negative association between varietal richness and its relative abundance, challenging the relationship between crop improvement and varietal diversity. Our results show that among cereal, pulse, and root and tuber crops, varietal diversity is lowest for cereals in Asia and highest for root and tubers in Africa. The analysis contributes new information useful to prioritize crops for which increasing varietal diversity may lead to more sustainable food systems.

Holocene fire history in China: Responses to climate change and human activities

Fire is an intrinsic feature of terrestrial ecosystems as well as a key Earth system process that significantly influences ecosystem patterns, the carbon cycle, and climate. Although local and regional paleofires across China have been investigated, the history of these phenomena at the national scale as well as possible drivers remain unknown. This study investigated spatiotemporal patterns in fire activity across China based on 107 individual site charcoal records. The aim of this work was to discuss the possible impact of climate and human activities on fire in China. Results showed that fire activities across China declined gradually overall between the early Holocene (12 ka BP) and the middle Holocene (7.3 ka BP) but then sharply increased in occurrence after 7.3 ka BP. Data showed that although regional fire activities did not vary synchronously, more events tended to occur in the late Holocene and there were relative less in the early-to-middle Holocene. These changes in Holocene fire activity closely mirrored millennial scale moisture variations across China. Intensified human activities over the last 3 ka might also be responsible for a sharp increase in fire activity. Variable trends in fire activities within regions might also be attributed to large-scale climatic controls modulated by local factors, which determined burn likelihood. This study enhances our insights into the fire history of China and may help to provide improved future projections for such phenomena given current climate change.

Trend Analysis of Temperature Data for the Narayani River Basin, Nepal

The study of spatiotemporal variation in temperature is vital to assess changes in climate, especially in the Himalayan region, where the livelihoods of billions of people living downstream depends on water coming from the melting of snow and glacier ice. To this end, temperature trend analysis is carried out in the Narayani River basin, a major river basin of Nepal, characterized by three climatic regions: tropical, subtropical and alpine. Temperature data from six stations located within the basin were analyzed. The elevation of these stations ranges from 460 to 3800 m a.s.l. and the time period of available temperature data ranges from 1960–2015. Multiple regression and empirical mode decomposition (EMD) methods were applied to fill in missing data and to detect trends. Annual as well as seasonal trends were analyzed and a Mann–Kendall test was employed to test the statistical significance of detected trends. The results indicate significant cooling trends before 1970s, and warming trends after 1970s in the majority of the stations. The warming trends range from 0.028 to 0.035 °C year−1 with a mean increasing trend of 0.03 °C year−1 after 1971. Seasonal trends show the highest warming trends in the monsoon season, followed by winter and the premonsoon and postmonsoon season. However, the difference in warming rates between different seasons was not significant. An average temperature lapse rate of −0.006 °C m−1 with the steepest value (−0.0064 °C m−1) in the premonsoon season and the least negative (−0.0052 °C m−1) in the winter season was observed for this basin. A comparative analysis of the gap-filled data with freely available global climate dataset show reasonable correlation, thus confirming the suitability of the gap filling methods.

Rainfall Threshold for Shallow Landslides Initiation and Analysis of Long-Term Rainfall Trends in a Mediterranean Area

The effects of climate change on landslide activity may have important environmental, socio-economic, and political consequences. In the last decades, several short-term extreme rainfall events affected Mediterranean regions, resulted in damaging geo-hydrological processes and casualties. It is unequivocal that the impact of landslides in several Mediterranean countries is increasing with time, but until now, there has been little or no quantitative data to support these increases. In this paper, both rainfall conditions for the occurrence of shallow landslides and rainfall trends were investigated in the Portofino promontory, which extends in the Ligurian Sea, where heavy rainfall and related ground effects often occur. Adopting a frequentist approach, the empirical intensity-duration threshold was estimated. Our findings highlight that the rainfall intensity required to trigger landslides is lower for the same duration than those expected in other similar environments, suggesting a high susceptibility to rainfall-induced landslides in the Portofino territory. Further, the Mann-Kendall test and Hurst exponent were used for detecting potential trends. Analysis of long-term rainfall time series showed statistically significant increasing trends in short duration precipitation occurrence and rainfall rates, suggesting a possible future scenario with a more frequent exceedance of the threshold triggering value and an increase of landslide risk.

Impacts of irrigated agriculture on food-energy-water-CO2 nexus across metacoupled systems

Irrigated agriculture has important implications for achieving the United Nations Sustainable Development Goals. However, there is a lack of systematic and quantitative analyses of its impacts on food–energy–water–CO₂ nexus. Here we studied impacts of irrigated agriculture on food–energy–water–CO₂ nexus across food sending systems (the North China Plain (NCP)), food receiving systems (the rest of China) and spillover systems (Hubei Province, affected by interactions between sending and receiving systems), using life cycle assessment, model scenarios, and the framework of metacoupling (socioeconomic-environmental interactions within and across borders). Results indicated that food supply from the NCP promoted food sustainability in the rest of China, but the NCP consumed over four times more water than its total annual renewable water, with large variations in food–energy–water–CO₂ nexus across counties. Although Hubei Province was seldom directly involved in the food trade, it experienced substantial losses in water and land due to the construction of the South-to-North Water Transfer Project which aims to alleviate water shortages in the NCP. This study suggests the need to understand impacts of agriculture on food–energy–water–CO₂ nexus in other parts of the world to achieve global sustainability.

Local human activities can lead to cross-border environmental impacts through the food–energy–water–CO₂ nexus. Here, the authors report wide variations in environmental impacts of irrigated agriculture across counties within the North China Plain under different environmental and socioeconomic scenarios.

Spatial variation in biodiversity loss across China under multiple environmental stressors

Biodiversity is essential for the maintenance of ecosystem health and delivery of the Sustainable Development Goals. However, the drivers of biodiversity loss and the spatial variation in their impacts are poorly understood. Here, we explore the spatial-temporal distributions of threatened and declining ("biodiversity-loss") species and find that these species are affected by multiple stressors, with climate and human activities being the fundamental shaping forces. There has been large spatial variation in the distribution of threatened species over China's provinces, with the biodiversity of Gansu, Guangdong, Hainan, and Shaanxi provinces severely reduced. With increasing urbanization and industrialization, the expansion of construction and worsening pollution has led to habitat retreat or degradation, and high proportions of amphibians, mammals, and reptiles are threatened. Because distributions of species and stressors vary widely across different climate zones and geographical areas, specific policies and measures are needed for preventing biodiversity loss in different regions.

Prediction of Autumn Precipitation over the Middle and Lower Reaches of the Yangtze River Basin Based on Climate Indices

Autumn precipitation (AP) has important impacts on agricultural production, water conservation, and water transportation in the middle and lower reaches of the Yangtze River Basin (MLYRB; 25°–35° N and 105°–122° E). We obtain the main empirical orthogonal function (EOF) modes of the interannual variation in AP based on daily precipitation data from 97 stations throughout the MLYRB during 1980–2015. The results show that the first leading EOF mode accounts for 30.83% of the total variation. The spatial pattern shows uniform change over the whole region. The variance contribution of the second mode is 16.13%, and its spatial distribution function shows a north-south phase inversion. Based on previous research and the physical considerations discussed herein, we include 13 climate indices to reveal the major predictors. To obtain an acceptable prediction performance, we comprehensively rank the climate indices, which are sorted according to the values of the new standardized algorithm of information flow (NIF, a causality-based approach) and correlation coefficient (a traditional climate diagnostic tool). Finally, Tropical Indian Ocean Dipole (TIOD), Arctic Oscillation (AO), and other four indicators are chosen as the final predictors affecting the first mode of AP over the MLYRB; NINO3.4 SSTA (NINO3.4), Atlantic-European Circulation E Pattern (AECE), and other four indicators are the major predictors for the second mode. In the final prediction experiment, considering the time series prediction of principal components (PCs) to be a small-sample problem, the Bayesian linear regression (BLR) model is used for the prediction. The experimental results reveal that the BLR model can effectively capture the time series trends of the first two modes (the correlation coefficients are greater than 0.5), and the overall performance is significantly better than that of the multiple linear regression (MLR) model. The prediction factors and precipitation prediction results identified in this study can be referenced to rapidly obtain climatological information for AP over the MLYRB and improve the regional prediction of AP elsewhere, which will also help policymakers prepare appropriate adaptation and mitigation measures for future climate change.

Evaporation abrupt changes in the Qinghai-Tibet Plateau during the last half-century

Pan evaporation (E_pan) was regarded as a critical indicator of climate change, especially in the Qinghai-Tibet Plateau (QTP). By using the measured daily E_pan data of 274 stations in the QTP from 1970 to 2017, the study detected abrupt changes in annual E_pan series in different spatial scales, through integrating the Mann-Kendall abrupt change test, moving t-test and piecewise linear fitting model. Results showed that abrupt changes existed generally in the QTP where mean and trend abrupt changes were detected in 76.6% and 97.8% of 274 stations during the last half-century. Major abrupt change time of mean values and trends was respectively in around 1996, 1989 and 2007. In comparison, early abrupt changes were observed in the south (south of 30°N) and north (north of 35°N) but late ones in the midland (30–35°N). Corresponding to the low frequent behaviors, pan evaporation paradox only existed in the QTP as a whole in 1970–1990 and was not apparent at site scale, with less than 9.5% of 274 stations detected in different periods. The results confirmed prevailing abrupt change of pan evaporation and its distinct spatial pattern in the QTP.

Trend Analysis of Temperature Data for Narayani River Basin, Nepal

Study of spatiotemporal dynamics of temperature is vital to assess changes in climate, especially in the Himalayan region where livelihoods of billions of people living downstream depends on water coming from the melting of snow and glacier ice. To this end, temperature trend analysis is carried out in Narayani river basin, a major river basin of Nepal characterized by three climatic regions: tropical, subtropical and alpine. Temperature data from six stations located within the basin were analyzed. The elevation of these stations ranges from 460 to 3800 m a.s.l. and the time period of available temperature data ranges from 1960–2015. Multiple regression and empirical mode decomposition (EMD) methods were applied to fill in missing data and to detect trends. Annual as well as seasonal trends were analyzed and a Mann-Kendall test was employed to test the statistical significance of detected trends. Results indicate significant cooling trends before 1970s, and warming trends after 1970s in the majority of the stations. The warming trends range from 0.028 ∘C year−1 to 0.035 ∘C year−1 with a mean increasing trend of 0.03 ∘C year−1 after 1971. Seasonal trends show highest warming trends in the monsoon season followed by winter, pre-monsoon, and the post-monsoon season. However, difference in warming rates between different seasons was not significant. An average temperature lapse rate of −0.006 ∘C m−1 with the steepest value (−0.0064 ∘C m−1) in pre-monsoon season and least negative (−0.0052 ∘C m−1) in winter season was observed for this basin. A comparative analysis of the gap-filled data with freely available global climate datasets show reasonable correlation thus confirming the suitability of the gap filling methods.

Trend Analysis of Temperature Data for Narayani River Basin, Nepal

Study of spatiotemporal dynamics of temperature is vital to assess changes in climate, especially in the Himalayan region where livelihoods of billions of people living downstream depends on water coming from the melting of snow and glacier ice. To this end, temperature trend analysis is carried out in Narayani river basin, a major river basin of Nepal characterized by three climatic regions: tropical, subtropical and alpine. Temperature data from six stations located within the basin were analyzed. The elevation of these stations ranges from 460 to 3800 m a.s.l. and the time period of available temperature data ranges from 1960–2015. Multiple regression and empirical mode decomposition (EMD) methods were applied to fill in missing data and to detect trends. Annual as well as seasonal trends were analyzed and a Mann-Kendall test was employed to test the statistical significance of detected trends. Results indicate significant cooling trends before 1970s, and warming trends after 1970s in the majority of the stations. The warming trends range from 0.028 °C year−1 to 0.035 °C year−1 with a mean increasing trend of 0.03 °C year−1 after 1971. Seasonal trends show highest warming trends in the monsoon season followed by winter, pre-monsoon, and the post-monsoon season. However, difference in warming rates between different seasons was not significant. An average temperature lapse rate of −0.006 °C m−1 with the steepest value (−0.0064 °C m−1) in pre-monsoon season and least negative (−0.0052 °C m−1) in winter season was observed for this basin. A comparative analysis of the gap-filled data with freely available global climate datasets shows reasonable correlation thus confirming the suitability of the gap filling methods.

Evolution of multiple global virtual material flows

The world is connected through multiple flows of material, but a comprehensive assessment of their temporal dynamics and interactions is rare. To address this knowledge gap, we assessed the evolution and interactions of global flows of virtual water, energy, land, CO₂, nitrogen as well as financial capital embodied in international trade from 1995 to 2008. We found that the volumes of all these flows, except for land flow, increased over time. Financial capital flows increased most (188.9%), followed by flows of CO₂ (59.3%), energy (58.1%), water (50.7%) and nitrogen (10.5%), while land transfer decreased by 8.8%. Volumes of virtual material flows among distant countries were much higher than those among adjacent countries. The top five countries accounted for a surprisingly large proportion (47% to 80%) of total flow volumes. Different kinds of virtual material flows tended to enhance each other through synergistic effects, and CO₂ and nitrogen flows tended to have stronger positive synergetic impacts on the other virtual material flows. Our results suggest that it is important to pay particular attention to such fast-growing material flows, promote cooperation between distant countries, and target countries with the largest flows to achieve global sustainable development goals.

Global Agricultural Trade Pattern in A Warming World: Regional Realities

Global warming, coupled with disparate national population growth projections, could exert significant pressure on food prices, increasing the risk of food insecurity, particularly for net-importing countries. We investigated projected eventualities for a comprehensive set of 133 countries by the year 2030, and identified changes in the global agricultural crop trading pattern, with simulations from a multi-regional computable general equilibrium (CGE) model. We based our model on population growth and temperature scenarios, as per the IPCC fifth assessment report (AR5). Our simulations suggest an increase of 4.9% and 6.4% in global average prices and aggregate export crop volumes, respectively. This global exports expansion requires an increased 4.46% in current global aggregate crop output, since population growth raises demand, and thus, global average crop prices, further aggravating net importing countries’ financial burdens for food acquisition. Conversely, net exporting countries will fare better in the projected scenario due to increased agricultural income, as they are able to increase crop exports to meet the rising global demand and price. The gap in global income distribution widens, given that the majority of developing countries are coincidently located in tropical zones which are projected to experience negative crop yield shocks, while industrialized countries are located in cold and temperate zones projected to have favorable crop yield changes. National and international policy measures aimed at effectively alleviating net importing countries’ food security issues should also consider how global crop yields are geographically and diversely impacted by climate change.