Indus River Research Articles

Evaluation of drought events using multiple drought indices under climate change in the Upper Indus Basin.

Spatiotemporal variations in drought events were examined through multiple drought indices in the Upper Indus Basin (UIB) during the 1980-2020 period using observed climate data of precipitation, temperature (T max., T min., and T mean), and potential evapotranspiration (PET) from 16 meteorological stations. Software like ClimPACT2 (to quality check data and generate SPI, SPEI, and CDD drought indices), DrinC (to generate AI, eRDI and PD drought indices), CMhyd (to bias correct NASA POWER gridded data), and ArcGIS (to map extreme drought years) were used in this study. It was revealed that precipitation decreased at 30mm/decade and maximum and minimum temperatures increased at 0.132°C/decade and 0.23°C/decade, aridity increased by decreasing aridity index at 0.15/decade, and number of consecutive dry days increased at 2days/decade. All drought indices reflected decreasing trends, indicating a warming and drying climatic regime. The eRDI drought index analysis revealed that droughts have occurred for 12.6years in the last four decades, and mild droughts (15%) are more common, followed by moderate droughts (9.4%), severe droughts (4.7%), and extreme droughts (2.4%). The study provides comparisons of drought patterns under changing climate in three distinct climatic and physical regions of UIB, i.e., Jammu, Kashmir, and Ladakh, and reveals that the UIB is not free from droughts.

Assessment of Water Poverty Index (WPI) Under Changing Land Use/Land Cover in a Riverine Ecosystem of Central India

Watershed Development is a very common phenomenon in the river basins in India due to its dynamic and continuously changing nature, which are interconnected via. Land use/land cover (LULC) change and water poverty scenario over time. In the present study, the samples were chosen from seven sampled villages for the Water Poverty Index (WPI) in the upper Tons River Basin. Among them, Ghunwara and Maihar Village exhibit the highest and lowest WPI, i.e., 98.1 and 62.91 out of 100, respectively. This indicates that villages with a high WPI face challenges in their water requirements, regardless of the seasonal river serving the basin area. Conversely, villages with a low WPI can satisfy their water needs solely from the basin. The present analysis of the Upper Tons River Basin suggests that Land Use and Land Cover (LULC) will undergo influences or adjustments at various stages, ultimately affecting agricultural land in the impact region. It also becomes evident that areas with limited land use and land cover (LULC) extensions exhibit lower Water Productivity Index (WPI), primarily due to their reliance on agricultural land. It is observed that alterations, reductions, or modifications in LULC lead to changes in multiple aspects of agricultural land, resulting in noticeable variations in various metrics. The present paper not only evaluates the land use in the Upper Tons River Basin spanning from 2001 to 2021 but also highlights the changing patterns that impact water resources and their utilization capacity. Furthermore, the study estimates the influence of reducing specific features on the distribution of WPI and other LULC parameters. The Upper Tons River Basin faces challenges such as unfavorable rainfall patterns and inadequate planning for irrigation at the fundamental and local levels. Additionally, its geographical location in a rainfed area negatively affects the WPI.

Elevation-Dependent Snow Cover Dynamics and Associated Topo-Climate Impacts in Upper Indus River Basin

In the present study, Improved Moderate Resolution Imaging Spectro-radiometer (MODIS) snow cover product (MOYDGL06*) has been used to evaluate the snow cover area (SCA) in Kabul, Jhelum, and Indus river basins for the time period of 2003 – 2020 with available MODIS land surface temperature (LST), and CHIRPS (precipitation) with objectives to evaluate the spatio-temporal SCA, and climate variables with respect to different elevations analyzed from Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Global Digital Elevation Model Version 3 (GDEM v3) and also to correlate the climatic variables with SCA. The results presented average annual SCA is around 50.7% – 64.7% in sub-basins of UIB, further it has been observed that SCA is decreasing on annual and seasonal timescale in all three basins. Elevation-dependent SCA, temperature, and precipitation presented a mix of trend on annual, seasonal, and monthly timescale at lower and higher altitude in all selected basins. Moreover, it was noticed that topography (slope, & aspect) also influences the SCA in the region. Furthermore, it has been examined that temperature has significant inverse relationship with SCA at middle and higher altitude in Indus, while in Kabul, and Jhelum no significant relationship observed at extreme lower and higher altitudes. It is also evident from relationship between SCA and climate variable that temperature is significantly responsible for decreasing trend of SCA rather than intense precipitation in all three river basins. Thus, all these elevation-dependent changes can improve our hydrological understanding which can have a considerable implication for hydrology, climate science, water resource management and socio-economic activities.

Influence of the Southern Hemisphere Supergyre on Antarctic Intermediate Water Properties in CMIP6 Models

AbstractThe supergyre in the Southern Hemisphere is thought to connect the Atlantic, Indian, and Pacific subtropical gyres together. The aim of the study is to investigate whether the supergyre is identifiable in the Coupled Model Intercomparison Project Phase 6 (CMIP6) models and in the Estimating the Circulation and Climate of the Ocean (ECCO) reanalysis and to evaluate the influence of the supergyre on the properties of Antarctic Intermediate Water (AAIW), the dominant water mass at intermediate depths in the Southern Hemisphere. CMIP6 models and ECCO are in agreement at the surface with supergyres connected across all basins but present some differences at depth in both position and strength. AAIW core properties (temperature and salinity) present a high degree of similarity across basins within the supergyre but not outside of it. By the end of the century, the supergyre reduces in size and intensifies at intermediate depths, and the AAIW core depth warms in all basins and freshens in the Pacific although no clear trend in salinity can be found in the Atlantic and Indian basins in the SSP5‐8.5 scenario. The high degree of similarity across basins within the supergyre is maintained in the future scenario. The results suggest that by connecting the basins together at intermediate depth, the supergyre plays a key role in circulating and homogenizing the AAIW core properties. Our results emphasize the role of the supergyre in circulating water masses at the surface and intermediate depths in CMIP6 models and hence its importance to the global circulation.

Performance evaluation of irrigation outlets with physical model study in Indus basin irrigation system of Pakistan.

The efficiency of water distribution at primary, secondary, and tertiary levels in the Indus Basin Irrigation System (IBIS) has historically suffered due to poor design, suboptimal operation, and water scarcity. To address these issues, the system has been designed with ungated irrigation outlets to ensure equitable water allocation at secondary and tertiary levels. This research evaluates the hydraulic performance of three irrigation outlets: adjustable proportional module (APM), adjustable orifice semi-module (AOSM), and open flume (OF) using a physical model study. A distributary channel model with these outlets was constructed at the Centre of Excellence in Water Resources Engineering, where discharge coefficients (Cd) were calibrated and measured under various hydraulic and geometric conditions, including free and submerged flow conditions, and with adjustments to flow depths and outlet settings. The results showed variability in Cd values under free flow and submerged flow conditions with APM and AOSM ranging from 6.07 to 8.20 and 0.56 to 0.74, respectively, and OF between 2.46 and 4.31. Additionally, the behavior of outlet tampering on Cd values was also assessed under three scenarios: tampering with the half wing wall (1st), tampering with the full wing wall (2nd), and lowering the bed level downstream of the outlet (3rd). The increase in Cd values for APM and AOSM was + 10.84% and + 14.49% under 1st scenario, + 17.12% and + 22.36% under 2nd scenario, and + 24.25% and + 26.30% under 3rd scenario, respectively. The results reveal that even minor tampering with outlet structures can lead to significant deviations in performance, highlighting the importance of maintaining stringent control over outlet configurations to ensure equitable and efficient water distribution. There is a critical need for rigorous, site-specific calibration of irrigation outlets to optimize their performance under local conditions and redesigning outlet structures to minimize the impacts of tampering, thereby enhancing the overall sustainability of water use in large-scale irrigation systems. The findings from this study provide essential insights for irrigation engineers and policymakers tasked with upgrading and maintaining irrigation infrastructure. By adopting a more customized approach to outlet design and management, it is possible to significantly improve water use efficiency and achieve more sustainable irrigation practices.

Basin-scale spatio-temporal development of glacial lakes in the Hindukush-Karakoram-Himalayas

Glacial lakes are expanding exponentially in the cryospheric environment of the Hindukush-Karakoram-Himalayas (HKH). Rapid glacier melting due to an above mean global annual temperature increase in HKH is attributed as the main reason for the expansion of the glacial lakes. The rapid expansion of glacial lakes increases the risk of future Glacial Lake Outburst Floods (GLOFs) events in the HKH.In the present study, glacial lake inventories for the Indus, Ganga and Brahmaputra (IGB) river basins in the HKH were generated for 1990, 2000, 2010 and 2020 using Landsat (TM & OLI) at the sub-basin level to understand the spatio-temporal and regional patterns of glacial lakes dynamics, elevational evolution, and changes in the typology. We mapped 17,641 glacial lakes (area: 1082.57 ± 192.601 km2) in 1990, 18,206 (area: 1120.95 ± 198.49 km2) in 2000, 18,399 (area: 1147.12 ± 201.26 km2) in 2010, and 19,284 (area: 1191.81 ± 209.21 km2) in 2020. Between 1990 and 2020, IGB basins showed an increase of 9.31 % in total number and 10.09 % in total area of glacial lakes. In 2020, the Brahmaputra basin had the maximum total area (area: 763.59 ± 132.14 km2), followed by Indus basin (area: 217.47 ± 43.39 km2) and the Ganga basin (area: 210.74 ± 33.66 km2). However, between 1990 and 2020, glacial lakes in the Ganga basin (n: 22.08 %) had the highest growth rate, followed by the Indus basin (n: 14.73 %) and the Brahmaputra basin (n: 4.41 %). In 2020, 76.11 % of glacial lakes were end-moraine-dammed M(e) lakes, followed by other bedrock-dammed B(o) lakes (16.45 %), supraglacial lakes (2.79 %), lateral moraine-dammed M(l) lakes (2 %), cirque B(c) lakes (1.06 %), other moraine-dammed M(o) lakes (0.38 %), and other glacial (O) lakes (1.18 %). Given the rapid growth of glacial lakes in the region along with their likely flood volumes and damage potential in case of their failures, the present study will be of importance for disaster management authorities, an important input for detection of potentially hazardous glacial lakes and for development of mitigation strategies to minimize the impact of potential future GLOF events.

Navigating Transboundary Waters: Geomorphological Insights for Collaborative Watershed Management in the Upper Indus Basin

Navigating Transboundary Waters: Geomorphological Insights for Collaborative Watershed Management in the Upper Indus Basin

Flood-induced variation and source apportionment of microplastics in Jia Bharali River of mid-Brahmaputra Valley, India.

In the present time, microplastics (MPs) are a cause of growing concern in freshwater environments throughout the globe. Flood accelerates the transport of MPs from river into the marine environment. However, there is a lack of research on the impact of flood on microplastic abundance and distribution in Indian rivers. This study aims to investigate the flood-induced variation of MPs along the stretch of the Jia Bharali River, one of the major tributaries of the river Brahmaputra. The mean concentration of MPs during post-flooding was highest (27.94 ± 9.25 MPs/L in surface water and 29 ± 8.73 MPs/kg in sediments) as compared to pre-flooding period (22.35 ± 5.55 MPs/L in surface water and 19.42 ± 6.08 MPs/kg in sediments). During pre-flood, fibres account for the majority of MP particles (36.13% in surface water and 38.23% in sediments). Similar results were observed for post-flooding surface water samples as fibres were the most dominant type (35.65%), while in the case of sediments, fragments (34.10%) were the major type. Polyethylene was the dominant polymer type of MPs followed by polypropylene. Polymer hazard index (PHI) indicated high risk, while the coefficient of microplastic impact (CMPI) showed an 'average' to 'minimum' risk level in the studied area. The study identified flooding, runoff from agricultural fields and various anthropogenic activities as the potential source of MPs in the river. The present study unveiled new insights into microplastic contamination of an Indian river, its source analysis, flood-induced distribution and risk assessment which will aid in mitigating and remediating freshwater microplastic pollution in the future.

Comprehensive assessment of fish diversity and water health in river Indus, Khyber Pakhtunkhwa, Pakistan.

Fish diversity and water quality are vital indicators of the health of freshwater ecosystems, however these systems are increasingly threatened by environmental changes and anthropogenic activities. This investigation aimed to assess the fish diversity and evaluate the physicochemical parameters of water at Ghazi Swabi near Tarbela Dam, River Indus, Khyber Pakhtunkhwa, Pakistan, between March and June 2020. Monthly water samples were collected and analyzed for various physicochemical parameters such as temperature, dissolved oxygen (DO), total dissolved solids (TDS), pH, turbidity, salinity, and concentrations of heavy metals including lead (Pb), copper (Cu), cadmium (Cd), and mercury (Hg). Using various nets and traps the fish specimens were collected with the help of local fishermen. Morphometric and meristic analyses were conducted to identify the species, while systematic keys were used to remove misidentifications. A total of 110 fish specimens were collected, representing 7 species across 6 genera, 3 families, and 3 orders. The family Cyprinidae was the most abundant, with species including Puntius conchonius, Puntius waageni, Crossocheilus diplocheilus, Barilius modestus, and Aspidoparia morar. The Belonidae family was represented by Xenentodon cancila, and the Ambassidae family by Chanda nama. Physicochemical analysis showed that the water quality remained within permissible limits for aquatic life, however higher levels of certain heavy metals were detected, which may pose long-term risks. The study concluded that the fish diversity at Ghazi Swabi near Tarbela Dam reflects a moderately healthy ecosystem, the presence of heavy metals in the water raises concerns about future ecological health. Regular monitoring and mitigation efforts are recommended to preserve biodiversity and maintain water quality. The study suggests the need for sustainable management practices to protect freshwater ecosystems from anthropogenic impacts.

Engineering properties assessment and aggregate suitability of the jurassic and eocene limestone: a case study from the Upper Indus Basin, Pakistan

Engineering properties assessment and aggregate suitability of the jurassic and eocene limestone: a case study from the Upper Indus Basin, Pakistan

Impact of sea surface temperature fronts on the spatial distribution of jellyfish in the northern Arabian sea

Identifying the spatial distribution of species and their relationship with environmental factors is crucial for conservation and management efforts. In Pakistan, jellyfish are economically significant and serves as an important fishery resource. This study utilized both in-situ and satellite data to investigate the relationship between fish catch and sea surface temperature (SST) gradient magnitude (GM). Notably, an unusually high subsurface Chlorophyll a (Chl-a) level (∼1.5 mg/m3) was observed, significantly higher than surrounding waters (∼0.5 mgm−3). Additionally, on October 27 at station 6, a high SST GM of 0.097 °C km−1 was recorded alongside an elevated subsurface Chl-a of 1.24 mg/m3. Low salinity levels (<36.2 psμ) were detected in areas with strong frontal activity, while higher levels (>36.7 psμ) were observed in the surrounding regions. Moreover, a high wind stress curl (>0.4 N/m3) was noted in regions with strong SST fronts along coastal and offshore areas of Balochistan and Sindh. A strong correlation (R2 = 0.987) was identified between annual fish catch and catch per unit effort (CPUE). The study revealed a significant fish catch (>200 kg) along the Balochistan coast and the Indus River estuary, with the exception of one offshore catch station. Results also indicated a strong correlated (R2 = 0.73, p < 0.001) between SST GM and fish catch in the upper layer (<50 m depth). By establishing a GM threshold at 0.06 °C km−1, there was an 80% likelihood of achieving a high catch within the upper 50 m layer. These findings enhance our understanding of how SST fronts influence the spatial distribution of jellyfish and improve our ability to forecast jellyfish fishing grounds in the northern Arabian Sea.

Estimation of soil loss and sediment yield by using the modified RUSLE model in the Indus River basin, including the quantification of error and uncertainty in remote-sensing images

Context Indus River is the cradle of Pakistani lifeline, and its lower reaches are prone to soil loss owing to bank erosion. Aims The aim was to investigate the sediment yield in the Lower Indus River Basin (LIRB), while addressing challenges related to error or uncertainty in remote-sensing data. Methods We employed a modified revised universal soil loss equation (RUSLE) model, integrating high-resolution digital elevation model (DEM) and calibrated Climate Hazards Group InfraRed Precipitation with station data (CHIRPS). Additional data layers, including land use, soil and cropping data, were also utilised. Key results The extent of actual soil erosion ranges from minimum to maximum erosion; 38.9% area lies in the range &gt;50 Mg ha‒1 year‒1, whereas 23.2% area lies in the range of 0–10 Mg ha‒1 year‒1, and 18.1% area lies in the range of 10–20 Mg ha‒1 year‒1. Conclusions The study identifies critical erosion areas and tackles uncertainties in remote-sensing data. The spatial analysis showed that higher distribution sediment erosion along the channel flow direction from the northern part of LIRB to the Arabian Sea. Implications The findings have provided critical information for policymakers and water managers to implement effective measures to reduce erosion, maintain soil integrity and promote the sustainability of the Indus River system.

Tree-ring maximum latewood density reveals unprecedented warming and long-term summer temperature in the upper Indus Basin, northern Pakistan

Understanding long-term temperature variability in the Upper Indus Basin (UIB), northern Pakistan, and its driving mechanisms is challenging due to the scarcity of long observational records and available literature. In this study, we reconstructed a 651-year (1370–2020 CE) warm-season (March–September) temperature record using the tree-ring maximum latewood density (MXD) of blue pine (Pinus wallichiana). The reconstruction explains 57 % of the variance in actual temperature during the common calibration period (1972–2020 CE). Our analysis identified ten high-temperature periods (temperature > 20.9 °C) and nineteen low-temperature periods (temperature < 19.8 °C), with the coldest years being 1392, 1707, 1817, and 1837, and the warmest years being 2013, 2016, 2017, and 2018. Spatial correlation analysis reveals a significant positive correlation with field temperature, predominantly in neighboring regions, and a significant negative correlation with relative humidity and precipitation. Multi-taper spectral analysis shows inter-annual (1.9, 2.5, 2.7, 5.5 years) and interdecadal (11, 18, 23, 25, 40, 71 years) cycles, suggesting a potential linkage with the Atlantic Multidecadal Oscillation (AMO). The negative linkage between our reconstruction and the region's standardized Palmer Drought Severity Index (scPDSI) indicates that continued temperature increase could result in severe drought in northern Pakistan in the near future. During the 20th century, the UIB experienced two distinct warming phases: 1948–1970 CE and 1994–2020 CE. The warming rate during 1994–2020 CE was 0.5 °C higher, indicating unprecedented recent warming. The reconstructed temperature record also demonstrates a large-scale spatiotemporal signal and a strong connection with most recorded volcanic eruptions. These findings enhance our understanding of long-term temperature variability in the region, highlighting the significance of MXD in reconstructing past temperature patterns.

Assessment of Basin‐Scale Concurrent Dry and Wet Extreme Dynamics Under Multimodel CORDEX Climate Scenarios

ABSTRACTThe impact of extreme events in risk analysis depends on factors such as magnitude, duration, timing and whether the system recovers fully before the next event occurs. While previous studies have primarily examined the drivers and characteristics of individual extremes, less focus has been given to the concurrent or compounding nature of extremes across adjacent seasons. Thus, understanding the dynamics of such compound extremes, particularly dryness and wetness, is crucial. To address these concerns, a Multi Scalar Drought Index (MSDI) is formulated using precipitation and temperature data from three river basins (Brahmani, Baitarani and Cauvery) of eastern and southern India. The combinations of dryness and wetness, such as Dry‐Dry, Dry‐Wet, Wet‐Dry and Wet‐Wet, between consecutive seasons are analysed across four seasons (summer, rainy, autumn and winter). The prolonged dryness/wetness along with dry/wet year are evaluated from baseline (1979–2018) to projected COrdinated Regional Climate Downscaling Experiment (CORDEX) future period (2020–2099). The spatio‐temporal variations in intra‐annual dry‐wet extremes are identified using the Mann–Kendall test. The results suggest that the eastern Indian river basins, particularly the Brahmani and Baitarani basins, experience more frequent occurrences of compounding dryness‐wetness compared to Cauvery river which is a southern Indian basin. Future scenarios indicate a trend towards dryness during the monsoon season in Brahmani and Baitarani basins, with frequent wet extremes in late autumn and winter. Abrupt transitions between dryness and wetness are prevalent during the Rainy‐Autumn and Autumn‐Winter seasons in Brahmani and Baitarani basins. The increased frequency of compound dry‐wet extremes poses significant socio‐economic risks, including reduced agricultural productivity, water management challenges and heightened vulnerability of local livelihoods dependent on consistent water availability. The results of this study provide a scientific reference for sustainable agriculture and water resource management to predict future seasonal dry and wet alternations and develop effective mitigation strategies.

The Characterization of Aquifer Parameters in Using Skimming Tubewells Through the Pumping Test Method: A Case Study of Tando Allahyar

Sindh is in the lower reaches of the Indus River; it is most vulnerable to a variety of upstream water development challenges. The aim of this research was to determine aquifer characteristics in the command area of Tando Allahyar-II distributary within the culmination of underground water potential. The hydraulic properties of the aquifer as well as the susceptibility of the formation to tedious extraction and saltwater upcoming were recognized. Three pumping tests were performed at head, middle, and tail reaches along the selected distributary. The drawdowns were measured at head reach (5.1667 h), at middle reach (6.0 h), and at tail reach (19.667 h) of the selected distributary by performing the pumping tests. Groundwater levels were lower at the tail reach compared to those at the head and middle reaches, likely due to a higher concentration of tubewells in the lower reach. The head and middle reaches showed higher groundwater levels, possibly due to constant head conditions promoting infiltration and recharge. The pumping test versus drawdown analysis revealed that the tubewells should be run with 7-h (on) and 4-h (off) operation. Further, the tubewells at all reaches (head, middle, and tail) should be closed for a minimum of 4 h between operations. This strategy would allow safe groundwater extraction, maintain water quality, and prevent water table depletion in the study area. The hydrodynamic and hydro-salinity behaviors were scrutinized in PWMIN 5.3 (version) by means of the MODFLOW mode. The results were estimated to compare the calibration and validation simulation outcomes using measured data. The model was successfully calibrated, and the root mean square (RMS) value of the head tubewell varied between 0.024 and 0.108, whereas it speckled between 0.0166 and 0.0349 for the middle tubewell and between 0.0659 and 0.0069 for the tail tubewell. The RMS values for hydrodynamic behavior for the head, middle, and tail reaches were less than 10%. These values represent a suitable match between the observed and simulated heads when a water table depletion of 1 to 2 m was observed due to extreme pumping. However, the average relative error values, for all validated procedures, were less than 10%.

Seasonal occurrence and ecological risk assessment of polycyclic aromatic hydrocarbons in the sediments and water in the left-bank canals of Indus River, Pakistan.

This study investigated a pressing environmental concern: the presence, distribution, sources, and ecological implications of sixteen polycyclic aromatic hydrocarbons (PAHs) in the left-bank canals of Kotri barrage-Akram, Pinyari, and Phuleli of the Indus River in Pakistan. These vital waterways, crucial for industrial, domestic, and agricultural activities, are experiencing contamination threats from anthropogenic sources, particularly PAHs. The study collected three water and two sediment samples from each canal in pre-monsoon and post-monsoon seasons. Then the EPA's liquid-liquid extraction method and gas chromatography determined the concentrations of PAHs. The findings of this study reveal alarming contamination levels, with pre-monsoon concentrations ranging from 22.256 to 836.455ng/L in water and 1,459.941 to 43,179.243ng/g in sediments. The post-monsoon concentrations ranged from 60.352 to 5663.058ng/L in water and 2976.770 to 15,238.335ng/g in sediments. The diagnostic ratios and principal component analysis (PCA) identified multiple sources of contamination, including industrial and domestic wastewater discharge, solid waste burning, vehicular emissions, biomass combustion, and petroleum residues. Furthermore, the assessment of the toxic equivalency factor (TEF) underscored the heightened carcinogenic potential of certain PAHs, notably benzo(a)pyrene and benzo(a)anthracene. Thus, the high levels of PAH contamination pose severe health risks to both human populations and aquatic ecosystems, emphasizing the urgency of addressing this issue. Stricter regulations governing industrial and domestic waste discharge, advocacy for cleaner fuel technologies, and the implementation of effective waste management practices must be initiated as crucial strategies in safeguarding the environmental integrity of the left-bank canals and the health of the surrounding communities.

A reappraisal of Mesozoic-Cenozoic sequence stratigraphy in Offshore Indus Basin, Pakistan

The Offshore Indus Basin is a passive continental margin and a frontier zone for hydrocarbon exploration based on structural and stratigraphic features observed on seismic data. In this study, the seismic and biostratigraphic framework is established using seismic data, geophysical well logs, along with biostratigraphic information to define the depositional sequences in the study region. A re-examination of the seismic data exhibits normal faults and a total of six seismic sequences ranging from Cretaceous to Quaternary. Nummulites atacicus, Nummulites globulus, Discocyclina sp., Miscellanea miscella, and Ranikothalia sp. are the major identified fauna in the Karachi South A1 well (2030–2724 m). The Miscellanea miscella, Ranikothalia, and Discocyclina sp. ages range from 55 to 56.5, 55–59, and 55–59 Ma respectively. Employing biostratigraphy, Ranikothalia/Miscellanea miscella/Discocyclina biozone (55–59 Ma), a single sequence, a third order cycle of deposition and transgressive and highstand system tracts have been recognized in the Karachi South A1 well. Linking biostratigraphic results to seismic stratigraphy indicates that the strata located in the range of 2030–2724 m is of the Ranikot (Paleocene) Formation and has been previously given Eocene age rather than the Paleocene using vintage seismic data. The environment of deposition of the Ranikot Formation in the Karachi South A1 well is the subtidal environment of the middle-shelf (30–45m depth) setting.

Drivers of Widespread Floods in Indian River Basins

Abstract Widespread floods affecting multiple subbasins in a river basin have implications for infrastructure, agriculture, environment, and groundwater recharge. However, the crucial linkage between widespread floods and their drivers remains unexplored for Indian subcontinental river basins. Here, we examine the occurrence and drivers of widespread flooding in seven Indian subcontinental river basins during the observed climate (1959–2020). The peninsular river basins have a high probability of widespread flooding, compared to the transboundary basins of the Ganga and Brahmaputra. Favorable antecedent baseflow and soil moisture conditions, uniform precipitation distribution, and precipitation seasonality determine the probability of widespread floods in Indian river basins. The widespread floods are associated with large atmospheric circulations that cause precipitation in a large part of a river basin. Our findings highlight the prominent drivers and mechanisms of widespread floods with implications for flood mitigation in India.

Exploring the Effects of Floods in Pakistan: Pre/Post Flood Analysis 2022

Pakistan is affected by floods of various intensities ranging between high, moderate and low levels. The aim of this study is to evaluate the effects of 2022 flood events in Pakistan. This aim will be achieved by analyzing the relationship between the 2022 floods and the situation of affected communities, with a focus on gender roles. The study assessed the differences in vulnerability to floods between men vs. women by examining their socio-economic conditions before and after flood 2022. Multiple field surveys were conducted for data collection, and a questionnaire was used to learn about the current and past conditions of the people living in the villages around the city of Khipro, Sindh, located downstream of the Indus River, majorly affected by floods in terms of lives and livelihoods. Correlations, and cross-tabulations were used to analyze the demographic characteristics and socioeconomic status of communities. Focusing on the period before and after the 2022 floods and the difference in vulnerability, the results of the study indicated that despite having better access to disaster preparedness information and resources, societal norms and mobility issues make women more vulnerable. Therefore, it is important to focus on gender-sensitive disaster preparedness and response efforts. The study proposes a few measures to improve resilience and promote sustainable development in flood-affected areas.Top of Form

Multi-covariate non-stationary flood frequency analysis for assessing flood hazard over the Mahanadi River basin, India

ABSTRACT Due to climate change and anthropogenic activities, the river’s peak flow is changing, which prompts exploring the non-stationary flood frequency analysis. Most of the past studies modelled the non-stationarity of floods, considering time and/or a single dominant covariate influencing the flood flows, but they are inadequate. This study proposes a multi-covariate non-stationary flood frequency model (MC-NSFFM) and investigates the influence of different covariates, such as rainfall, modified reservoir index (MRI), and climate indices, for the Mahanadi River basin in India. The models’ performances are evaluated by comparing them with the results of stationary and single-covariate non-stationary flood frequency models (SC-NSFFMs) using standard performance measures and return period analysis. The study showed that the MC-NSFFMs performed better than stationary and SC-NSFFMs. The flood return levels corresponding to the MC-NSFFMs are 4% to 22% higher than the stationary models, indicating the rise in flood risks due to climate change and anthropogenic activities.