Problems and Challenges for Groundwater Management in South Asia

This study investigated heavy metal contamination in drinking water in five Asian regions (East, Southeast, South, Central, and West Asia) with an interest in inorganic arsenic (iAs), lead (Pb), mercury (Hg), cadmium (Cd), chromium (Cr) and nickel (Ni). Human exposure, risks, and the disease burdens in terms of loss of disability-adjusted life years (DALYs) were analyzed. Concentrations of heavy metals and risks in different regions were variable. Hazard index (HI), cancer risk (CR) and DALYs were used as the health metrics. The total cancer risk was highest in Southeast Asia (2.18 × 10−4) followed by South Asia (1.61 × 10−4), West Asia (1.04 × 10−4), Central Asia (8.85 × 10−5) and East Asia (3.94 × 10−5). Cancer risks exceeding 1 × 10−4 (1 in 10,000) were considered higher risk while Southeast Asia had the highest risk. In terms of population-adjusted DALY, South Asia had the highest (1.95 × 105) followed by Southeast Asia (8.66 × 104), East Asia (2.34 × 104), West Asia (1.91 × 104) and Central Asia (4.60 × 103). Lung cancer emerged as the main outcome in all regions, accounting for 85% and 94% of cancer risks, and DALYs respectively. The findings highlight regional disparities, requiring intervention strategies in a few regions. The actions may include implementing regulations, treatment technologies and establishing monitoring systems to ensure water quality.

Aridity index reflects the exchanges of energy and water between the land surface and the atmosphere, and its variation can be used to forecast drought and flood patterns, which makes it of great significance for agricultural production. The ratio of potential evapotranspiration and precipitation is applied to analyse the spatial and temporal distributions of the aridity index in the Belt and Road region under the 1.5°C and 2.0°C global warming scenarios on the basis of outputs from four downscaled global climate models. The results show that: (1) Under the 1.5°C warming scenario, the area-averaged aridity index will be similar to that in 1986–2005 (around 1.58), but the changes vary spatially. The aridity index will increase by more than 5% in Central-Eastern Europe, north of West Asia, the monsoon region of East Asia and northwest of Southeast Asia, while it is projected to decrease obviously in the southeast of West Asia. Regarding the seasonal scale, spring and winter will be more arid in South Asia, and the monsoon region of East Asia will be slightly drier in summer compared with the reference period. While, West Asia will be wetter in all seasons, except winter. (2) Relative to 1986–2005, both areal averaged annual potential evapotranspiration and precipitation are projected to increase, and the spatial variation of aridity index will become more obvious as well at the 2.0°C warming level. Although the aridity index over the entire region will be maintained at approximately 1.57 as that in 1.5°C, the index in Central- Eastern Europe, north of West Asia and Central Asia will grow rapidly at a rate of more than 20%, while that in West Siberia, northwest of China, the southern part of South Asia and West Asia will show a declining trend. At the seasonal scale, the increase of the aridity index in Central-Eastern Europe, Central Asia, West Asia, South Asia and the northern part of Siberia in winter will be obvious, and the monsoon region in East Asia will be drier in both summer and autumn. (3) Under the scenario of an additional 0.5°C increase in global temperature from 1.5°C to 2.0°C, the aridity index will increase significantly in Central Asia and north of West Asia but decrease in Southeast Asia and Central Siberia. Seasonally, the aridity index in the Belt and Road region will slightly increase in all other seasons except spring. Central Asia will become drier annually at a rate of more than 20%. The aridity index in South Asia will increase in spring and winter, and that in East Asia will increase in autumn and winter. (4) To changes of the aridity index, the attribution of precipitation and potential evapotranspiration will vary regionally. Precipitation will be the major influencing factor over southern West Asia, southern South Asia, Central-Eastern Siberia, the non-monsoon region of East Asia and the border between West Asia and Central Asia, while potential evapotranspiration will exert greater effects over Central-Eastern Europe, West Siberia, Central Asia and the monsoon region of East Asia.

In the globe, South Asia or Southern Asia represents the southern region of the Asian continent, which comprises the sub-Himalayan countries, adjoining countries to the west and east. South Asia is bounded on the south by the Indian Ocean and on land by West Asia, Central Asia, East Asia and Southeast Asia. The current territories of Bangladesh, India and Pakistan form the central region of South Asia, while the mountain countries of Nepal and Bhutan in the north and island countries of Sri Lanka and Maldives in the south are generally included in the region. Often Afghanistan and Myanmar are also added.

Chapter 5 - Cereal-Based Cropping Systems in Asia: Nutrition and Disease Management

Economic vulnerability is an important indicator to measure regional coordination, health and stability. Despite the importance of vulnerabilities, this is the first study that presents 26 indicators selected from the dimensions of the domestic economic system, external economic system and financial system in the Belt and Road Initiative (BRI) countries. A quantitative analysis is conducted to analyze the characteristics of spatial heterogeneity of vulnerability of the economic subsystems and the comprehensive economic system of the BRI countries and the main influencing factors of the comprehensive economic system vulnerability (CESV) are identified based on obstacle degree model. The results show that the CESV of the East Asia, South Asia and ASEAN countries are lower than that of the Middle Eastern Europe, Central Asia and West Asia countries. The CESV of the BRI countries are generally in the middle level and the average vulnerability index of highly vulnerable countries is twice as much as that of lowly vulnerable countries. In addition, in terms of the vulnerability of the three subsystems, the spatial distribution of vulnerability of the domestic economic system (DESV) and financial system (FSV) is basically consistent with the spatial distribution pattern of CESV, both of which are low in East Asia and South Asia and high in West Asia and Central Asia. While, the vulnerability of external economic system (EESV) shows a different spatial pattern, with vulnerability of West Asia, Central Asia and ASEAN higher than that of East Asia and South Asia. The main obstacle factors influencing the CESV of BRI countries include GDP growth rate, saving ratio, ratio of bank capital to assets, service industry level, industrialization level and loan rate. Therefore, the key way to maintain the stability and mitigate the vulnerability of the economic system of BRI countries is to focus on the macroeconomic development and operation, stimulate the economy and market vitality, promote the development of industries, especially the service and secondary industries, and optimize the economic structure, banking system and financial system.

The article analyzes the implementation of the Sustainable Development Goals for the eradication of poverty in the world and by regions in 2000 - 2020. Significant progress has been made in reducing the share of the employed population living below the poverty line in the world as a whole. Uneven progress has been identified in reducing the share of the employed population below the poverty line by region (reductions in East Asia, Southeast Asia, Central Asia, South Asia, Oceania, sub-Saharan Africa; increases in West Asia, North Africa, and Latin America and the Caribbean); uneven progress in social protection assistance (increase in the share of the population covered by at least one type of social protection assistance in South Asia, East Asia, Oceania and Sub-Saharan Africa; reduction in South-East Asia, North Africa, Latin America and the Caribbean, Central and Western Asia). There has been an improvement in the results of access to basic services for the poorest sections of the population (increase in the share of the population using basic drinking water services, access to basic sanitation services) with a simultaneous slowdown in access to basic services by region since 2010. A sharp reduction during 2000-2019 in the provision of official development assistance to developed countries aimed at reducing poverty. Measures have been identified in the field of financing poverty eradication programs (intensification of international cooperation for development) (implementation of indicators of official development assistance by developed countries), implementation of effective measures in the areas of domestic public resources, private business).

Hypertension among adolescents in Asia is an emerging public health concern that is directly associated with early onset cardiovascular risks. As such, it can also lead to further health issues and challenges for health care in the future. As existing studies have predominantly focussed on adult populations, we sought to provide targeted insights into adolescent hypertension across Asia, elucidating the impact of rapid lifestyle and environmental changes on this younger population. Therefore, in this systematic review, we aimed to evaluate the prevalence and trends of elevated blood pressure (BP) and hypertension among adolescents aged 10-19 years across Asia, address gaps in region-specific data, and determine any demographic risk factors. Following PRISMA guidelines, we searched PubMed, EMBASE, Science Direct, Web of Science, Google Scholar, and Scopus for cross-sectional studies on adolescent hypertension/elevated BP in Asia published from January 2019 to June 2024, after which we narratively synthesised their findings. Of the 2634 retrieved studies, 39 met the inclusion criteria, covering over 200 000 adolescents in Asia. The prevalence of hypertension ranges from 0.7% in urban Bangladesh to 24.5% in urban Malaysia, with urban areas generally showing higher rates than rural areas (e.g. India: 8.4% urban vs. 5.7% rural). By region, East Asia has the highest overall prevalence (14.25%), followed by West Asia (14.14%), South Asia (13.77%), Southeast Asia (13.16%), and Central Asia (12.37%). Males had higher prevalence rates (for example, 22.3% in Chinese males vs. 20% in females). The increasing prevalence of adolescent hypertension in urban Asia is a significant public health concern. Although extensive research has been conducted in East and South Asia, there is a dearth of studies in Western, Southeast, and Central Asia, emphasising a need for future research. Standardised diagnostic criteria and targeted interventions are crucial for addressing regional disparities and reducing long-term cardiovascular risks.

This chapter investigates non-areal contact between Malayo-Polynesian languages from Southeast Asia and Madagascar (MPSEA) and languages from other families found in four regions: South Asia, West Asia, East Asia, and Europe. It considers lexical borrowing, typological convergence, and influence through language planning policies. Malay was the main vector through which South Asian and West Asian loanwords entered other MPSEA languages. In the opposite direction, Malay also lent the largest number of borrowings to non-Austronesian languages, comprising both inherited and borrowed words. In general, lexical influence from MPSEA languages on the languages of South Asia, West Asia, East Asia, and Europe chiefly pertained to regionally specific products, concepts, and inventions. Meanwhile, prestigious languages such as Sanskrit and Arabic were responsible for the introduction of several abstract concepts into Malay and Javanese, whereas the Philippine languages have mostly drawn from Spanish and English for this purpose, Tetun from Portuguese, and Malagasy from French and English. These source languages continue to inspire language users, particularly in the realm of post-independence language engineering.

Aim. To consider the impact of the COVID-19 coronavirus pandemic and special military ope­ration on the structure of the international derivatives market. Tasks. To characterize the regional structure of the international derivatives market; to analyze the specifics of trade by region, country, exchange and underlying assets; to identify key trends in the international derivatives market and the factors forming them during the COVID-19 coronavirus pandemic and special military operation. Methods. General scientific methods of research (analysis and synthesis, induction, classifica­tion, etc.), as well as computational and analytical methods were used. Results. Two key trends were identified in the study of changes in international derivatives trading activity. First, the Asia-Pacific region, led by India and China, has taken the lead in the international derivatives trade structure in terms of trade volume. The U.S. region, led by the United States and Brazil, has lagged far behind the Asia-Pacific region in terms of trade activ­ity since the launch of the special military operation, which may entail capital outflows from America to East and South Asia. Second, the West Asian region, which includes a number of countries in the Near and Middle East, led by Turkey and Iran, is a new player in the deriva­tives market, which has entered into competition with the European region. During the COVID-19 coronavirus pandemic, the West Asian region actively increased derivatives trading volumes. The most popular underlying assets of derivatives were stocks, whose trading volume during the pandemic approached the trading volume of the European region as a whole, which includes the European Union countries, Great Britain and Russia. After the start of the special military operation, the drop in volumes in the European region put the West Asian region in third place in the international structure of derivatives trading activity, indicating the growing competi­tion between West Asia and Europe. Conclusions. The transformation of the international market based on the outflow of trade activity to South, East and West Asia during the COVID-19 coronavirus pandemic and special military operation forms a qualitatively new interaction of participants in the international derivatives market. India, China, Turkey and Iran are new key players in the Asian region. Their interaction creates prerequisites for the creation of a contour of new economic mutually advan­tageous interaction in the world economic system, in which the competition is between the regions of South Asia, East Asia and America, as well as between West Asia and the European region. To form a clearer contour of the participants of the new economic interaction, further research on the centers of capitalization in the international derivatives market and the basis for their formation, as well as infrastructure research aimed at studying the transatlantic and continental system of interconnection of exchanges is needed.

Aerosols continue to contribute the largest uncertainty in quantifying Earth’s climate change. The uncertainty associated with aerosol radiative forcing is found to be higher over Asia. The simulation and future projection of aerosol impact on climate may not be highly accurate over Asia due to rapid changes in aerosol emissions, limitations in simulating the observed aerosol trends, and the non-availability of regional distribution of columnar aerosol parameters based on high-quality observational datasets on a seasonal scale. For the first time, this comprehensive study examines the spatial and regional variations of aerosol columnar optical and physical properties (aerosol optical depth (AOD), fine mode fraction (FMF), and single scattering albedo (SSA)) and their associated radiative effects (aerosol radiative forcing (ARF) and heating rate (HR)) using high-quality Aerosol Robotic Network (AERONET) datasets on seasonal and annual scales over Asia. This study is performed over a total of 44 selected AERONET observational sites covering different regions of Asia, e.g., Central, South, South-East, and East Asia. AOD, ARF at the surface and in the atmosphere, and aerosol-induced atmospheric HR are observed to be the highest over South Asia, followed by South-East, East, and Central Asia in each season. SSA is found to be lower over South and Central Asia compared to South-East and East Asia. The combined influence of both fine anthropogenic aerosol emissions (e.g., carbonaceous aerosols) from biomass burning and fossil fuel combustion, and coarse mode dust aerosols from seasonal transport lead to higher AOD (0.6) and lower SSA (0.90), which overall result in higher ARF (~−70 Wm-2 at surface and 40 Wm-2 in atmosphere) and HR (0.80 Kday-1) over South Asia. South-East and East Asia are dominated by fine aerosols (higher FMF) due to higher contributions from forest fire and anthropogenic emissions, respectively, and relatively less dominance of dust aerosols compared to Central and South Asia. In addition, the seasonal aerosol optical and radiative parameters over Asia are also compared and contrasted with other regions of the globe, e.g., North America, South America, Europe, Africa, and Australia, where aerosol emissions are significantly different and mostly lower than in Asia. These findings provide observational constraints that are crucial for the improvement in model simulations for accurately assessing the radiative and climatic impacts of aerosols over a global aerosol hotspot region, Asia, where the uncertainty associated with aerosol radiative forcing is found to be higher. Details of the spatiotemporal variations in aerosol characteristics over Asia will be presented, compared and contrasted with the rest of the world, and inferences will be drawn. 

Defining the ‘region’ before we begin to study something called ‘Asia’ we have to decide what it is we are studying. We have to decide what we include and what we exclude; we need to explain and justify our definition of ‘Asia’. This is important because, conceived extensively, Asia can be defined as all of the land mass on the continent of Asia east of the Mediterranean Sea, plus the islands of Japan and Southeast Asia. Map 1 provides a visual representation of this very extensive idea of Asia. We would face a difficult task if we employed this definition of Asia, as we would have to cover the following regions: West and Southwest Asia (often called the Middle East – Turkey, Israel, Lebanon, Jordan, Syria, Iraq, Iran, Saudi Arabia, and other countries) South Asia (or the sub-continent of Asia – India, Pakistan, Nepal, Bangladesh, Sri Lanka) Northern and Central Asia (Russia, the Central Asian states such as Turkmenistan, Uzbekistan, Kazakhstan, Kirgyzstan and so on) East Asia (China, Japan, North and South Korea. See Map 3.) Southeast Asia (mainland Southeast Asia – Vietnam, Cambodia, Laos, Thailand, Myanmar [Burma], Malaysia; and island Southeast Asia – parts of Malaysia, Singapore, Indonesia, Brunei, the Philippines, and East Timor. See Map 4.) The reader can see at a glance that if we attempted to cover such a huge geographical area, we could only do it very superficially.

In the 21st century, the Indian Ocean has increasingly become the vital sea area among the world’s major powers in terms of competitive influence with its superior geographical location and rich natural resources, and South Asia naturally becomes the center of geo-politics game among major powers. From a geographical point of view, South Asia has three distinguishing features. First, located in the intersection of Southeast Asia, West Asia and Central Asia, South Asia is adjacent to the western China, but the Himalayas become a barrier between South Asia and the Asian continent. The South Asian Subcontinent is also the hub connecting Europe, the Middle East, East Asia and Australia. Second, South Asia is in the center of the Indian Ocean and geographically forms a relatively independent unit, both the east and west parts are adjacent to the Bay of Bengal and the Arabian Sea, respectively. Third, India is located in the center of the South Asian Subcontinent, and other countries in South Asia including Pakistan, Bangladesh, Bhutan, Nepal, Maldives and Sri Lanka is either adjacent to India or separated by land or ocean, but the key is that there are not adjacent to each other. From the perspective of geopolitical value, in addition to the geographical advantages with its back against the Himalayas and with the sea on three sides, South Asia is also served as a wing of the world’s oil center the in Middle East, which not only pours into some competitive elements of the geopolitics for South Asia, but also lays a pivotal position for South Asia in the great powers’ global strategy. Among the said countries, India goes directly into the Indian Ocean for more than 1600 km. It is not only geographically located in the center of South Asia, but also accounts for 75, 63 and 78% of the entire South Asia in terms of population, area and GDP. As a result, India can be regarded as the political and security center in South Asia regardless of its size or resource advantages. In addition, as another important country in South Asia, Pakistan possesses nuclear weapons, but it can not compete with India in terms of the size and economic potential.

This paper uses data for the period 1950–2050 compiled by the United Nations Population Division together with methods including spatial autocorrelation analysis, hierarchical cluster analysis and the standard deviational ellipse, to analyze the spatio-temporal evolution of population and urbanization in the 75 countries located along the routes of the Silk Road Economic Belt and the 21st-century Maritime Silk Road, to identify future population growth and urbanization hotspots. The results reveal the following: First, in 2015, the majority of Belt and Road countries in Europe, South Asia and Southeast Asia had high population densities, whereas most countries in Central Asia, North Africa and West Asia, as well as Russia and Mongolia, had low population densities; the majority of countries in South Asia, Southeast Asia, Central Asia, West Asia and North Africa had rapid population growth, whereas many countries in Europe had negative population growth; and five Belt and Road countries are in the initial stage of urbanization, 44 countries are in the acceleration stage of urbanization, and 26 are in the terminal stage of urbanization. Second, in the century from 1950 to 2050, the mean center of the study area’s population is consistently located in the border region between India and China. Prior to 2000, the trajectory of the mean center was from northwest to southeast, but from 2000 it is on a southward trajectory, as the population of the study area becomes more concentrated. Future population growth hotspots are predicted to be in South Asia, West Asia and Southeast Asia, and hotspot countries for the period 2015–2030 include India, China, Pakistan and Indonesia, though China will move into negative population growth after 2030. Third, the overall urban population of Belt and Road countries increased from 22% in 1950 to 49% in 2015, and it is expected to gradually catch up with the world average, reaching 64% in 2050. The different levels of urbanization in different countries display significant spatial dependency, and in the hundred-year period under consideration, this dependency increases before eventually weakening. Fourth, between 2015 and 2030, urban population hotspots will include Thailand, China, Laos and Albania, while Kuwait, Cyprus, Qatar and Estonia will be urban “coldspots.” Fifth, there were 293 cities with populations over 1 million located along the Belt and Road in 2015, but that number is expected to increase to 377 by 2030. Of those, 43 will be in China, with many of the others located in India, Indonesia and the eastern Mediterranean.

In this work, we extracted the near-surface CO2 concentration from the Greenhous gases Observing SATellite (GOSAT) and the National Oceanic and Atmospheric Administration (NOAA) CarbonTracker model datasets for a temporal period of 8 years from 2010 to 2017 to study the spatiotemporal distribution of near-surface CO2 and the factors affecting it over five regions of Asia including Central Asia, East Asia, South Asia, Southeast Asia, and West Asia. The near-surface CO2 datasets from both satellite and model were first validated against the ground-based CO2 observations obtained from the World Data Center for Greenhouse Gases (WDCGG) stations located in Asia to confirm their applicability and the results showed a good agreement between the datasets with significant correlations. The results from the time-series analyses showed a gradual increase in the near-surface CO2 with significant monthly and seasonal variations over all the regions. To study the factors affecting the spatial distribution of near-surface CO2, we investigated the relationship of near-surface CO2 with the anthropogenic CO2 emissions, terrestrial ecosystem, and winds. The results showed that over Asia, the anthropogenic CO2 emissions and winds primarily controlled the spatial distribution of near-surface CO2. However, in the areas where anthropogenic emissions were lower, the terrestrial ecosystem and winds affected the near- surface CO2 distribution. To study the factors controlling the temporal distribution of near-surface CO2, the relationship of near-surface CO2 with vegetation, precipitation, and relative humidity was investigated. The results showed an inverse relationship between near-surface CO2 and NDVI, precipitation, and relative humidity over monsoon-influenced regions, i.e., East Asia, South Asia, and Southeast Asia. However, a positive relation of near-surface CO2 was observed with precipitation and relative humidity over arid and semi-arid regions, i.e., Central Asia and West Asia. The results were also verified by determining the correlations among these variables.

Record-breaking rainfall occurred coherently over subtropical West Asia (WA) and East Asia (EA) in April 2024, causing catastrophic damages around the Persian Gulf and South China. Strong barotropic cyclones are directly responsible for the long-lasting extreme rainfall over WA and EA. Based on observational analyses and numerical simulations by a linear baroclinic model (LBM), here we show evidences that these two rainfall extremes are tele-connected and are tied to the record-breaking latent heat release over tropical Indian Ocean (TIO). The record-breaking latent heat release over TIO triggers a stationary Rossby wave train propagating northward, with a barotropic anticyclone over Northern Indian Ocean and a barotropic cyclone over WA, leading to extreme WA rainfall. The intense latent heat release associated with the extreme rainfall over WA triggers another stationary Rossby wave train along the Asian subtropical jet (ASJ), with a wavelength of about 50~55 degrees in longitude. This wave train anchors a downstream barotropic cyclone anomaly on the eastern periphery of Tibetan Plateau with southerly flow from South China Sea to Eastern China, in favor of excessive rainfall over the EA region.The above mechanism not only explains why rainfall extremes in WA and EA are located at a same latitude (20°-30°N) along the ASJ, but also clarifies why the intense rainfall over WA and EA occurred in April 2024 rather than other seasons. Spring 2024 was associated with a rapid decay of an El Niño event, and convection over TIO was suppressed by descending branch of Walker circulation before April. Along with the decay of warm SST anomaly over equatorial Pacific, TIO became warmer than Pacific in April, giving rise to intense convection over TIO which triggered the stationary Rossby waves. Although record-strong latent heating anomaly over TIO persisted from April into May in 2024, the substantially northward shifted ASJ in May cannot anchor the stationary Rossby waves in response to TIO heating, since subtropical circulation response to tropical heating is strongly dependent on the basic state flow. This work highlights the importance of both basic state and tropical heating anomaly in shaping tele-connected Asian climate extremes during the decaying phase of El Niño.