Your search found 23 records
1 Pavelic, Paul; Sikka, Alok; Alam, Mohammad Faiz; Sharma, Bharat R.; Muthuwatta, Lal; Eriyagama, Nishadi; Villholth, Karen G.; Shalsi, S.; Mishra, V. K.; Jha, S. K.; Verma, C. L.; Sharma, N.; Reddy, V. R.; Rout, S. K.; Kant, L.; Govindan, M.; Gangopadhyay, P.; Brindha, K.; Chinnasamy, P.; Smakhtin, V. 2021. Utilizing floodwaters for recharging depleted aquifers and sustaining irrigation: lessons from multi-scale assessments in the Ganges River Basin, India. Colombo, Sri Lanka: International Water Management Institute (IWMI). 20p. (Groundwater Solutions Initiative for Policy and Practice (GRIPP) Case Profile Series 04) [doi: https://doi.org/10.5337/2021.200]
Groundwater management ; Groundwater recharge ; Aquifers ; Floodwater ; Water use ; Groundwater depletion ; Groundwater irrigation ; Sustainable use ; Groundwater flow ; Transfer of waters ; Flood control ; Groundwater table ; Water storage ; Water quality ; Pumping ; Technology ; Pilot projects ; Assessment ; Risk management ; Cost benefit analysis ; Stakeholders ; Community involvement ; Socioeconomic aspects ; Livelihoods ; Food security ; Irrigated farming ; Environmental impact ; River basins ; Ponds ; Wells ; Monsoons ; Rain ; Drought / India / Ganges River Basin / Ramganga Basin / Uttar Pradesh / Rampur / Jiwai Jadid
(Location: IWMI HQ Call no: IWMI Record No: H050171)
(3.67 MB)
Pragmatic, cost-effective, socially inclusive and scalable solutions that reduce risks from recurrent cycles of floods and droughts would greatly benefit emerging economies. One promising approach known as Underground Transfer of Floods for Irrigation (UTFI) involves recharging depleted aquifers with seasonal high flows to provide additional groundwater for irrigated agriculture during dry periods, while also mitigating floods. It has been identified that there is potential for implementing the UTFI approach across large parts of South Asia. The first pilot-scale implementation of UTFI was carried out in a rural community of the Indo-Gangetic Plain in India, and performance of the approach was assessed over three years from a technical, environmental, socioeconomic and institutional perspective. The results are promising and show that UTFI has the potential to enhance groundwater storage and control flooding, if replicated across larger scales. The challenges and opportunities for more wide-scale implementation of UTFI are identified and discussed in this report. In areas with high potential for implementation, policy makers should consider UTFI as an option when making decisions associated with relevant water-related development challenges.
2 Alahacoon, Niranga; Edirisinghe, M. 2021. Spatial variability of rainfall trends in Sri Lanka from 1989 to 2019 as an indication of climate change. ISPRS International Journal of Geo-Information, 10(2):84. [doi: https://doi.org/10.3390/ijgi10020084]
Rainfall patterns ; Trends ; Climate change ; Spatial variation ; Weather hazards ; Climatic zones ; Natural disasters ; Precipitation ; Flooding ; Monsoons ; Drought ; Arid zones ; Semiarid zones ; Geographical information systems / Sri Lanka
(Location: IWMI HQ Call no: e-copy only Record No: H050312)
(3.82 MB) (3.82 MB)
Analysis of long-term rainfall trends provides a wealth of information on effective crop planning and water resource management, and a better understanding of climate variability over time. This study reveals the spatial variability of rainfall trends in Sri Lanka from 1989 to 2019 as an indication of climate change. The exclusivity of the study is the use of rainfall data that provide spatial variability instead of the traditional location-based approach. Henceforth, daily rainfall data available at Climate Hazards Group InfraRed Precipitation corrected with stations (CHIRPS) data were used for this study. The geographic information system (GIS) is used to perform spatial data analysis on both vector and raster data. Sen’s slope estimator and the Mann–Kendall (M–K) test are used to investigate the trends in annual and seasonal rainfall throughout all districts and climatic zones of Sri Lanka. The most important thing reflected in this study is that there has been a significant increase in annual rainfall from 1989 to 2019 in all climatic zones (wet, dry, intermediate, and Semi-arid) of Sri Lanka. The maximum increase is recorded in the wet zone and the minimum increase is in the semi-arid zone. There could be an increased risk of floods in the southern and western provinces in the future, whereas areas in the eastern and southeastern districts may face severe droughts during the northeastern monsoon. It is advisable to introduce effective drought and flood management and preparedness measures to reduce the respective hazard risk levels.
3 Pantha, K.; Acharya, K.; Mohapatra, S.; Khanal, S.; Amatya, N.; Ospina-Betancourth, C.; Butte, G.; Shrestha, S. D.; Rajbhandari, P.; Werner, D. 2021. Faecal pollution source tracking in the holy Bagmati River by portable 16S rRNA gene sequencing. npj Clean Water, 4:12. [doi: https://doi.org/10.1038/s41545-021-00099-1]
Water pollution ; Faecal pollution ; Coliform bacteria ; Faecal coliforms ; Biological contamination ; Rivers ; Water quality ; Sewage ; Wastewater treatment plants ; Sanitation ; Public health ; Indicators ; Monsoons / Nepal / Kathmandu Valley / Bagmati River
(Location: IWMI HQ Call no: e-copy only Record No: H050276)
(2.02 MB) (2.02 MB)
A suitcase laboratory was used for 16S rRNA amplicon sequencing to assess microbial water quality in the holy Bagmati River, Kathmandu, Nepal. SourceTracker analysis and Volcano plots revealed that microbial communities in the downstream part of the river were mainly contributed by untreated sewage. Seasonal variability in the sewage microbiome was reflected in the downstream river water quality. The bacterial genera Acidovorax, Geobacillus and Caulobacter predominated in the upstream sites, while genera containing putative human pathogens and gut bacteria, such as Clostridium, Prevotella, Arcobacter, Lactobacillus, Enterococcus and Streptococcus become prominent in the downstream sites. Marker gene qPCR assays for total bacteria, total coliforms, Human E. coli, Arcobacter butzleri and Vibrio cholerae confirmed the sequencing data trends. Even though basic sanitation provision is nowadays near universal in Nepal, our findings show how inadequate wastewater management may turn an urban river into an open sewer, which poses a public health risk.
4 Amarasinghe, Upali A.; Sikka, Alok; Mandave, Vidya; Panda, R. K.; Gorantiwar, S.; Ambast, S. K. 2021. Improving economic water productivity to enhance resilience in canal irrigation systems: a pilot study of the Sina Irrigation System in Maharashtra, India. Water Policy, 23(2):447-465. [doi: https://doi.org/10.2166/wp.2021.231]
Water productivity ; Economic analysis ; Irrigation systems ; Canals ; Resilience ; Cropping patterns ; Water allocation ; Groundwater irrigation ; Groundwater recharge ; Water costs ; Benefit-cost ratio ; Water use ; Drought tolerance ; Water scarcity ; Rain ; Monsoons ; Reservoir storage / India / Maharashtra / Sina Irrigation System
(Location: IWMI HQ Call no: e-copy only Record No: H050317)
https://iwaponline.com/wp/article-pdf/23/2/447/879066/023020447.pdf
https://vlibrary.iwmi.org/pdf/H050317.pdf
https://vlibrary.iwmi.org/pdf/H050317.pdf
(0.40 MB) (411 KB)
This paper proposes scenarios to achieve more crop per drop and irrigation for all in water-scarce irrigation systems, with a particular reference to India. It uses economic water productivity (EWP) and water cost curve for EWP as tools to reallocate irrigation consumptive water use (CWU) and identify economically viable cropping patterns. Assessed in the water-scarce Sina irrigation system in Maharashtra, India, the method shows that drought-tolerant annual crops such as fruits and/or fodder should be the preferred option in irrigated cropping patterns. Cropping patterns with orchard or fodder as permanent fixtures will provide sustainable income in low rainfall years. Orchards in combination with other crops will increase EWP and value of output in moderate to good rainfall years. Governments should create an enabling environment for conjunctive water use and allocation of CWU to achieve a gradual shift to high-value annual/perennial crops as permanent fixtures in cropping patterns.
5 Buisson, Marie-Charlotte; Balasubramanya, Soumya; Stifel, D. 2021. Electric pumps, groundwater, agriculture and water buyers: evidence from West Bengal. Journal of Development Studies, 57(11):1893-1911. [doi: https://doi.org/10.1080/00220388.2021.1906862]
Pumps ; Electricity ; Groundwater ; Agricultural production ; Rice ; Water market ; Irrigation practices ; Cropping patterns ; Crop yield ; Farmers ; Monsoons ; Energy ; Policies / India / West Bengal
(Location: IWMI HQ Call no: e-copy only Record No: H050372)
https://www.tandfonline.com/doi/pdf/10.1080/00220388.2021.1906862
https://vlibrary.iwmi.org/pdf/H050372.pdf
https://vlibrary.iwmi.org/pdf/H050372.pdf
(2.41 MB) (2.41 MB)
Irrigation with electric pumps is cheaper than with diesel pumps in West Bengal where electricity and diesel are unsubsidised, and where pump owners typically irrigate their winter rice crop and often sell water to farmers who do not own pumps. Using purposefully selected primary data, we examine whether electric-pump owners have greater water access and rice production during the monsoon and winter seasons compared to diesel-pump owners and water buyers. We also examine whether electric pump-owners provide greater access to irrigation services through water sales. We find that electric-pump ownership increased agricultural outputs both at the extensive and intensive margins in both seasons. The number of clients served by electric-pump owners was greater than those served by diesel-pump owners, but there was only a small difference in total irrigated areas, suggesting that electric-pump owners sell water to farmers with smaller land holdings. The evidence indicates that in an environment where inadequate irrigation has been one of the factors constraining agriculture, electric pumps have the potential to support agricultural growth and generate pro-poor side effects.
6 Sharma, C.; Shukla, A. K.; Zhang, Y. 2021. Climate change detection and attribution in the Ganga-Brahmaputra-Meghna river basins. Geoscience Frontiers, 12(5):101186. (Online first) [doi: https://doi.org/10.1016/j.gsf.2021.101186]
Climate change ; River basins ; Precipitation ; Hydrometeorology ; Anthropogenic factors ; Greenhouse gas emissions ; Temperature ; Monsoons ; Climatology ; Models / India / Nepal / China / Bangladesh / Ganga-Brahmaputra-Meghna River Basin
(Location: IWMI HQ Call no: e-copy only Record No: H050394)
https://www.sciencedirect.com/science/article/pii/S1674987121000505/pdfft?md5=0fcfe5e55998eba24917d3de574e2166&pid=1-s2.0-S1674987121000505-main.pdf
https://vlibrary.iwmi.org/pdf/H050394.pdf
https://vlibrary.iwmi.org/pdf/H050394.pdf
(2.59 MB) (2.59 MB)
Ganga-Brahmaputra-Meghna (GBM) river basin is the third-largest and one of the most populated river basins in the world. As climate change is affecting most of the hydrometeorological variables across the globe, this study investigated the existence of climate change signal in all four climatological seasons in the GBM river basin and assessed the contribution of anthropogenic activities, i.e., Greenhouse Gases (GHGs) emission in the change. Significant decreasing trends in the monsoon and a small increase in pre-monsoon precipitation were observed. Negligible change was detected in post-monsoon and winter season precipitation. CMIP5 GCMs were used for climate change detection, change point estimation, and attribution studies. Support Vector Machine (SVM) regression method was adopted to downscale GCM variables at the local scale. Monte-Carlo simulation approach was used to detect changes in different seasons. The climate change ‘signals’ were detectable after the year 1980 using Signal to Noise ratio (SNR) method in the majority of central and north-western regions. The change point was detectable only in annual monsoon precipitation at the basin level. Attribution analysis indicated >50% contribution of anthropogenic activities (GHGs) to annual monsoon precipitation changes. So, there is high confidence that monsoon precipitation in GBM has significantly changed due to anthropogenic activities. Different mitigation and adaption measures are also suggested, which may be adopted to manage the growing demand and water availability in the basin.
7 Monerie, P.-A.; Pohl, B.; Gaetani, M. 2021. The fast response of Sahel precipitation to climate change allows effective mitigation action. npj Climate and Atmospheric Science, 4:24. [doi: https://doi.org/10.1038/s41612-021-00179-6]
Climate change mitigation ; Precipitation ; Greenhouse gas emissions ; Carbon dioxide ; Sea surface temperature ; Monsoons ; Models ; Uncertainty / Africa / Sahel
(Location: IWMI HQ Call no: e-copy only Record No: H050395)
(1.95 MB) (1.95 MB)
Climate change will drive major perturbations of the West African summer monsoon. A zonal contrast in precipitation will develop at the end of the century, with an increase in precipitation over the central Sahel and a decrease in precipitation over the western Sahel. Such a zonal contrast results from the antagonist effects of the fast (due to enhanced radiative warming over land, and over the North Hemisphere, relative to the South Hemisphere) and slow (associated with long-term changes in oceanic circulation) responses of precipitation to increasing greenhouse gases. While such changes have already been assessed, less attention has been given to their temporality, an issue of major importance to promote efficient mitigation and adaptation measures. Here, we analyse the future evolution of precipitation changes decomposed into a fast and a slow response, showing that the fast response dominates the slow one. From this evidence, we highlight that mitigation strategies may be successful at reducing the effect of climate change on Sahel precipitation within a few decades, by muting the fast response. This decomposition also allows for a better understanding of the uncertainty of climate model predictions in Africa.
8 Khanal, S.; Lutz, A. F.; Kraaijenbrink, P. D. A.; van den Hurk, B.; Yao, T.; Immerzeel, W. W. 2021. Variable 21st century climate change response for rivers in high mountain Asia at seasonal to decadal time scales. Water Resources Research, 57(5):e2020WR029266. [doi: https://doi.org/10.1029/2020WR029266]
Climate change ; River basins ; Mountains ; Hydrology ; Models ; Time series analysis ; Water availability ; Precipitation ; Glaciers ; Snow cover ; Rainfall-runoff relationships ; Temperature ; Monsoons ; Discharges / Asia / Amu Darya Basin / Balkash Basin / Brahmaputra Basin / Ganges Basin / Helmand Basin / Indus Basin / Irrawaddy Basin / Mekong Basin / Salween Basin / Syr Darya Basin / Tarim Basin / Yangtze Basin / Yellow River / Tibetan Plateau
(Location: IWMI HQ Call no: e-copy only Record No: H050398)
https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2020WR029266
https://vlibrary.iwmi.org/pdf/H050398.pdf
https://vlibrary.iwmi.org/pdf/H050398.pdf
(4.00 MB) (4.00 MB)
The hydrological response to climate change in mountainous basins manifests itself at varying spatial and temporal scales, ranging from catchment to large river basin scale and from sub-daily to decade and century scale. To robustly assess the 21st century climate change impact for hydrology in entire High Mountain Asia (HMA) at a wide range of scales, we use a high resolution cryospheric-hydrological model covering 15 upstream HMA basins to quantify the compound effects of future changes in precipitation and temperature based on the range of climate change projections in the Coupled Model Intercomparison Project Phase 6 climate model ensemble. Our analysis reveals contrasting responses for HMA's rivers, dictated by their hydrological regimes. At the seasonal scale, the earlier onset of melting causes a shift in the magnitude and peak of water availability, to earlier in the year. At the decade to century scale, after an initial increase, the glacier melt declines by the mid or end of the century except for the Tarim river basin, where it continues to increase. Despite a large variability in hydrological regimes across HMA's rivers, our results indicate relatively consistent climate change responses across HMA in terms of total water availability at decadal time scales. Although total water availability increases for the headwaters, changes in seasonality and magnitude may diverge widely between basins and need to be addressed while adapting to future changes in a region where food security, energy security as well as biodiversity, and the livelihoods of many depend on water from HMA.
9 Brunetti, M. T.; Melillo, M.; Gariano, S. L.; Ciabatta, L.; Brocca, L.; Amarnath, Giriraj; Peruccacci, S. 2021. Satellite rainfall products outperform ground observations for landslide prediction in India. Hydrology and Earth System Sciences, 25(6):3267-3279. [doi: https://doi.org/10.5194/hess-25-3267-2021]
Landslides ; Forecasting ; Satellite observation ; Rain ; Precipitation ; Weather data ; Estimation ; Natural disasters ; Monsoons ; Datasets / India
(Location: IWMI HQ Call no: e-copy only Record No: H050491)
https://hess.copernicus.org/articles/25/3267/2021/hess-25-3267-2021.pdf
https://vlibrary.iwmi.org/pdf/H050491.pdf
https://vlibrary.iwmi.org/pdf/H050491.pdf
(5.89 MB) (5.89 MB)
Landslides are among the most dangerous natural hazards, particularly in developing countries, where ground observations for operative early warning systems are lacking. In these areas, remote sensing can represent an important detection and monitoring process to predict landslide occurrence in space and time, particularly satellite rainfall products that have improved in terms of accuracy and resolution in recent times. Surprisingly, only a few studies have investigated the capability and effectiveness of these products in landslide prediction in reducing the impact of this hazard on the population.
We have performed a comparative study of ground and satellite-based rainfall products for landslide prediction in India by using empirical rainfall thresholds derived from the analysis of historical landslide events. Specifically, we have tested Global Precipitation Measurement (GPM) and SM2RAIN-ASCAT satellite rainfall products, and their merging, at daily and hourly temporal resolution, and Indian Meteorological Department (IMD) daily rain gauge observations. A catalogue of 197 rainfall-induced landslides that occurred throughout India in the 13-year period between April 2007 and October 2019 has been used.
Results indicate that satellite rainfall products outperform ground observations thanks to their better spatial (0.1 vs. 0.25 ) and temporal (hourly vs. daily) resolutions. The better performance is obtained through the merged GPM and SM2RAIN-ASCAT products, even though improvements in reproducing the daily rainfall (e.g. overestimation of the number of rainy days) are likely needed. These findings open a new avenue for using such satellite products in landslide early warning systems, particularly in poorly gauged areas.
We have performed a comparative study of ground and satellite-based rainfall products for landslide prediction in India by using empirical rainfall thresholds derived from the analysis of historical landslide events. Specifically, we have tested Global Precipitation Measurement (GPM) and SM2RAIN-ASCAT satellite rainfall products, and their merging, at daily and hourly temporal resolution, and Indian Meteorological Department (IMD) daily rain gauge observations. A catalogue of 197 rainfall-induced landslides that occurred throughout India in the 13-year period between April 2007 and October 2019 has been used.
Results indicate that satellite rainfall products outperform ground observations thanks to their better spatial (0.1 vs. 0.25 ) and temporal (hourly vs. daily) resolutions. The better performance is obtained through the merged GPM and SM2RAIN-ASCAT products, even though improvements in reproducing the daily rainfall (e.g. overestimation of the number of rainy days) are likely needed. These findings open a new avenue for using such satellite products in landslide early warning systems, particularly in poorly gauged areas.
10 Chapagain, D.; Dhaubanjar, Sanita; Bharati, Luna. 2021. Unpacking future climate extremes and their sectoral implications in western Nepal. Climatic Change, 168(1-2):8. [doi: https://doi.org/10.1007/s10584-021-03216-8]
Climate change ; Extreme weather events ; Forecasting ; Trends ; Temperature ; Precipitation ; River basins ; Highlands ; Lowland ; Rain ; Monsoons ; Natural disasters ; Impact assessment ; Water resources ; Energy ; Agriculture ; Food security ; Forests ; Biodiversity ; Tourism ; Public health / Nepal / Karnali River Basin
(Location: IWMI HQ Call no: e-copy only Record No: H050668)
https://link.springer.com/content/pdf/10.1007/s10584-021-03216-8.pdf
https://vlibrary.iwmi.org/pdf/H050668.pdf
https://vlibrary.iwmi.org/pdf/H050668.pdf
(2.13 MB) (2.13 MB)
Existing climate projections and impact assessments in Nepal only consider a limited number of generic climate indices such as means. Few studies have explored climate extremes and their sectoral implications. This study evaluates future scenarios of extreme climate indices from the list of the Expert Team on Sector-specific Climate Indices (ET-SCI) and their sectoral implications in the Karnali Basin in western Nepal. First, future projections of 26 climate indices relevant to six climate-sensitive sectors in Karnali are made for the near (2021–2045), mid (2046–2070), and far (2071–2095) future for low-and high-emission scenarios (RCP4.5 and RCP8.5, respectively) using bias-corrected ensembles of 19 regional climate models from the COordinated Regional Downscaling EXperiment for South Asia (CORDEX-SA). Second, a qualitative analysis based on expert interviews and a literature review on the impact of the projected climate extremes on the climate-sensitive sectors is undertaken. Both the temperature and precipitation patterns are projected to deviate significantly from the historical reference already from the near future with increased occurrences of extreme events. Winter in the highlands is expected to become warmer and dryer. The hot and wet tropical summer in the lowlands will become hotter with longer warm spells and fewer cold days. Low-intensity precipitation events will decline, but the magnitude and frequency of extreme precipitation events will increase. The compounding effects of the increase in extreme temperature and precipitation events will have largely negative implications for the six climate-sensitive sectors considered here.
11 Nayak, M. A.; Hassan, W. U. 2021. A synthesis of drought prediction research over India. Water Security, 13:100092. [doi: https://doi.org/10.1016/j.wasec.2021.100092]
Drought ; Forecasting ; Monsoons ; Meteorological factors ; Precipitation ; Soil moisture ; Stream flow ; Runoff ; Monitoring ; El Nino-Southern Oscillation ; Modelling / India
(Location: IWMI HQ Call no: e-copy only Record No: H050641)
(2.74 MB)
A major section of India’s economy is directly linked with water-dependent food and energy systems. Skillful predictions of droughts play a pivotal role in sustainable water management and evading serious damages to agriculture production and economy of a region. Recent decades have witnessed valuable advances in scientific understanding and prediction of droughts in India. In this review, we synthesize major sources of drought predictability over different regions in India. We find that a few large-scale atmospheric and oceanic circulation patterns and regional scale hydrometeorological variables are key to understanding and predicting drought occurrences. We also present a concise summary of major statistical and dynamical forecasting-based modelling efforts in drought predictions. Although major strides have been taken in drought prediction in the recent decades, important gaps remain in understanding the onset and spatio-temporal dynamics of droughts.
Further, many opportunities of improving the skill of drought prediction over India are envisaged, and many impending challenges are highlighted. The overall picture is that significant efforts and investments are critical for understanding and skillfully predicting droughts over India.
Further, many opportunities of improving the skill of drought prediction over India are envisaged, and many impending challenges are highlighted. The overall picture is that significant efforts and investments are critical for understanding and skillfully predicting droughts over India.
12 Modak, S.; Ghosh, Surajit. 2021. Floods as agents of vitality: reaffirming human-nature synergies. Neuotting, Germany: Water Science Policy (WSP). 7p. (Water Science Policy Brief) [doi: https://doi.org/10.53014/REHQ6535]
Flooding ; Floodplains ; Flood control ; Governance ; Policies ; Zoning ; Regulations ; River basins ; Hydrological factors ; Riparian zones ; Communities ; Risk reduction ; Water resources ; International waters ; Ecosystems ; Wetlands ; Nutrients ; Monsoons / India / Nepal / Bangladesh / Ganga-Brahmaputra-Meghna Basin
(Location: IWMI HQ Call no: e-copy only Record No: H050792)
https://firebasestorage.googleapis.com/v0/b/water-science-policy.appspot.com/o/policyBriefs%2Fwsp%2Fflood_agents%2FWSP_10.53014%3AREHQ6535_Floods%20as%20agents.pdf?alt=media&token=59c06ed0-869d-47e7-a0c3-ec145f536a0a
https://vlibrary.iwmi.org/pdf/H050792.pdf
https://vlibrary.iwmi.org/pdf/H050792.pdf
(1.72 MB) (1.72 MB)
13 Alahacoon, Niranga; Edirisinghe, M.; Ranagalage, M. 2021. Satellite-based meteorological and agricultural drought monitoring for agricultural sustainability in Sri Lanka. Sustainability, 13(6):3427. [doi: https://doi.org/10.3390/su13063427]
Drought ; Monitoring ; Sustainable agriculture ; Weather hazards ; Precipitation ; Rain ; Temperature ; Monsoons ; Spatial analysis ; Remote sensing ; Satellite observation ; Vegetation index ; Moderate resolution imaging spectroradiometer / Sri Lanka
(Location: IWMI HQ Call no: e-copy only Record No: H050898)
(5.57 MB) (5.57 MB)
For Sri Lanka, as an agricultural country, a methodical drought monitoring mechanism, including spatial and temporal variations, may significantly contribute to its agricultural sustainability. Investigating long-term meteorological and agricultural drought occurrences in Sri Lanka and assessing drought hazard at the district level are the main objectives of the study. Standardized Precipitation Index (SPI), Rainfall Anomaly Index (RAI), and Vegetation Health Index (VHI) were used as drought indicators to investigate the spatial and temporal distribution of agriculture and meteorological droughts. Climate Hazards Group Infrared Precipitation with Stations (CHIRPS) data from 1989 to 2019 was used to calculate SPI and RAI. MOD13A1 and MOD11A2 data from Moderate Resolution Imaging Spectroradiometer (MODIS) from 2001 to 2019, were used to generate the Vegetation Condition Index (VCI) and Temperature Condition Index (TCI). Agricultural drought monitoring was done using VHI and generated using the spatial integration of VCI and TCI. Thus, various spatial data analysis techniques were extensively employed for vector and raster data integration and analysis. A methodology has been developed for the drought declaration of the country using the VHI-derived drought area percentage. Accordingly, for a particular year, if the country-wide annual extreme and severe drought area percentage based on VHI drought classes is =30%, it can be declared as a drought year. Moreover, administrative districts of Sri Lanka were classified into four hazard classes, No drought, Low drought, Moderate drought, and High drought, using the natural-beak classification scheme for both agricultural and meteorological droughts. The findings of this study can be used effectively by the relevant decision-makers for drought risk management (DRM), resilience, sustainable agriculture, and policymaking.
14 Kumar, M. D.; Kumar, S.; Bassi, N. 2022. Factors influencing groundwater behaviour and performance of groundwater-based water supply schemes in rural India. International Journal of Water Resources Development, 22p. (Online first) [doi: https://doi.org/10.1080/07900627.2021.2021866]
Water supply ; Groundwater recharge ; Aquifers ; Drinking water ; Water levels ; Water depth ; Water use ; Irrigation water ; Infiltration ; Monsoons ; Rain ; Policies ; Rural areas ; Sustainability ; Models / India / Maharashtra
(Location: IWMI HQ Call no: e-copy only Record No: H050915)
(1.48 MB)
This study investigates the factors influencing groundwater behaviour during the monsoon using data on rainfall, pre-monsoon depth of the water levels, groundwater level fluctuations, aquifer specific yield, and soil infiltration characteristics. It shows the effect of pre-monsoon depth of the water levels along with rainfall, soil infiltration and specific yield in controlling recharge during the monsoon. It also explores the factors influencing the performance of drinking water schemes. It shows that the intensity of irrigation demand, extent of gravity-based surface irrigation, aquifer storage space, and the aquifer recharge potential are important determinants for the sustainability of the groundwater-based drinking water schemes.
15 Jayawardena, I. M. S. P.; Punyawardena, B. V. R.; Karunarathne, M. D. R. K. 2022. Importance of integration of subseasonal predictions to improve climate services in Sri Lanka case study: southwest monsoon 2019. Climate Services, 26:100296. [doi: https://doi.org/10.1016/j.cliser.2022.100296]
Climate services ; Forecasting ; Monsoons ; Case studies ; Rain ; Precipitation ; Water reservoirs ; Hydroelectric power generation ; Decision making / Sri Lanka
(Location: IWMI HQ Call no: e-copy only Record No: H051064)
https://www.sciencedirect.com/science/article/pii/S2405880722000140/pdfft?md5=ef9c00f2a20476f596bd3405d25519b7&pid=1-s2.0-S2405880722000140-main.pdf
https://vlibrary.iwmi.org/pdf/H051064.pdf
https://vlibrary.iwmi.org/pdf/H051064.pdf
(7.53 MB) (7.53 MB)
The climate outlook for the 2019 southwest monsoon (SWM) season was prepared through an expert assessment of the prevailing global climate conditions and forecasts from different climate models from around the world during the fourteenth session of the South Asian Climate Outlook Forum (SASCOF14). Above-normal rainfall was predicted over Sri Lanka for SWM 2019, and information was shared at the monsoon forum. Even though SWM 2019 seasonal rainfall wasslightly above average, highly uneven rainfall distribution with a deficit of rainfall at the beginning and a surplus of rainfall during the latter part of the season was observed. Unusual dry conditioned prevailed during the month of May 2019, which led to delay the onset of SWM by 2 weeks. Due to the delay of onset and rainfall deficit during the early part of 2019 SWM, late cultivation of paddy was observed. Hydro-catchment areas recorded large shortfalls in early part Southwest Monsoon rainfall reducing hydropower generation to 15–18%, from May to July.
The suppressed phase of Madden Julian Oscillation (MJO) (phase 6 to 8) with anomalous easterly winds over Sri Lanka was evident from 04th May to 25th May. As MJO being a major predictive source in subseasonal timescale and Sri Lanka being a country located in the heart of the MJO envelope, integration of subseasonal information into seasonal outlook provide much greater value to decision-makers in Agriculture and Energy sector.
The suppressed phase of Madden Julian Oscillation (MJO) (phase 6 to 8) with anomalous easterly winds over Sri Lanka was evident from 04th May to 25th May. As MJO being a major predictive source in subseasonal timescale and Sri Lanka being a country located in the heart of the MJO envelope, integration of subseasonal information into seasonal outlook provide much greater value to decision-makers in Agriculture and Energy sector.
16 Maiti, A.; Acharya, P.; Sannigrahi, S.; Zhang, Q.; Bar, S.; Chakraborti, S.; Gayen, B. K.; Barik, G.; Ghosh, Surajit; Punia, M. 2022. Mapping active paddy rice area over monsoon Asia using time-series Sentinel – 2 images in Google Earth engine; a case study over Lower Gangetic Plain. Geocarto International, 37(25):10254-10277. [doi: https://doi.org/10.1080/10106049.2022.2032396]
Rice ; Mapping ; Satellite imagery ; Monsoons ; Time series analysis ; Case studies ; Farmland ; Precipitation ; Models / India / West Bengal / Lower Gangetic Plain
(Location: IWMI HQ Call no: e-copy only Record No: H051089)
(4.00 MB)
We proposed a modification of the existing approach for mapping active paddy rice fields in monsoon-dominated areas. In the existing PPPM approach, LSWI higher than EVI at the transplantation stage enables the identification of rice fields. However, it fails to recognize the fields submerged later due to monsoon floods. In the proposed approach (IPPPM), the submerged fields, at the maximum greenness time, were excluded for better estimation. Sentinel–2A/2B time-series images were used for the year 2018 to map paddy rice over the Lower Gangetic Plain (LGP) using Google earth engine (GEE). The overall accuracy (OA) obtained from IPPPM was 85%. Further comparison with the statistical data reveals the IPPPM underestimates (slope (b1) ¼ 0.77) the total reported paddy rice area, though R2 remains close to 0.9. The findings provide a basis for near real-time mapping of active paddy rice areas for addressing the issues of production and food security.
17 Hoque, Md. M.; Islam, A.; Ghosh, S. 2022. Environmental flow in the context of dams and development with special reference to the Damodar Valley Project, India: a review. Sustainable Water Resources Management, 8(3):62. [doi: https://doi.org/10.1007/s40899-022-00646-9]
Environmental flows ; Dams ; Rivers ; Aquatic organisms ; Fishes ; Aquatic ecosystems ; Water pollution ; Water quality ; Water resources ; Freshwater ; Stream flow ; Downstream ; Hydropower ; Monsoons ; Socioeconomic aspects ; Sustainability / India / West Bengal / Damodar Valley Project / Damodar River
(Location: IWMI HQ Call no: e-copy only Record No: H051181)
(4.05 MB)
Environmental flow is the minimum flow required in a fluvial system to maintain its ecological health and to promote socio-economic sustainability. The present work critically examines the concept of the environmental flow in the context of dams and development using a systematic methodology to find out the previous works published during the last 3 decades (1990–2020) in different search engines and websites. The study reviews that structural interventions in the form of dams, barrages, weirs, etc. impede the natural flow of the rivers. Moreover, other forms of development such as industrialization, urbanization, and expansion of modern agriculture also exacerbate the problems of environmental flow across the world, especially in monsoon Asia. The present case of the environmental flow for the Damodar River portrays that the construction of dams and barrages under the Damodar Valley Project have significantly altered the flow duration, flood frequency, and magnitude (high-frequency low magnitude events in the post-dam period), while urban-industrial growth in the basin has polluted the river water (e.g., lower dissolved oxygen and higher biological oxygen demand). This typical alteration in the flow characteristics and water quality has threatened aquatic organisms, especially fish diversity and community structure. This review will make the readers aware of the long-term result of dam-induced fluvial metamorphosis in the environment through the assessment of environmental flow, species diversity, flow fluctuation, and river pollution. The study may be useful for policy-making for ushering in the sustainable development pattern that will attract future researchers, planners, and stakeholders.
18 Mitra, Archisman; Balasubramanya, Soumya; Brouwer, R. 2023. Can cash incentives modify groundwater pumping behaviors? Evidence from an experiment in Punjab. American Journal of Agricultural Economics, 105(3):861-887. [doi: https://doi.org/10.1111/ajae.12340]
Groundwater level ; Pumping ; Incentives ; Agriculture ; Electricity supplies ; Energy consumption ; Irrigation ; Nexus approaches ; Pricing ; Farmers ; Groundwater extraction ; Rice ; Monsoons ; Pilot projects / India / Punjab / Fatehgarh Sahib / Hoshiarpur / Jalandhar
(Location: IWMI HQ Call no: e-copy only Record No: H051376)
https://onlinelibrary.wiley.com/doi/epdf/10.1111/ajae.12340
https://vlibrary.iwmi.org/pdf/H051376.pdf
https://vlibrary.iwmi.org/pdf/H051376.pdf
(0.91 MB) (927 KB)
As groundwater levels steadily decline in India, authorities are concerned about reducing extraction for irrigation purposes without jeopardizing food security. Very low or zero prices for electricity and water in agriculture is partly responsible for overextraction, but charging higher prices is politically not feasible. In this study, we describe the results of a pilot scheme implemented in Punjab, India, where farmers who enrolled were allocated a monthly entitlement of electricity units and compensated for unused electricity. Eight hours of uninterrupted daytime electricity supply were also provided under the scheme instead of the usual mix of daytime and night-time supply. Analyzing data from a cross-sectional farm household survey and instrumenting for enrollment, we find that self-reported hours of irrigation for enrolled farmers were significantly lower than for non-enrolled ones, with no impact on rice yields. We also find a reduction in monthly electricity consumption at electricity-feeder level due to the pilot scheme using the synthetic control method. Our results suggest that the combination of daytime electricity provision and cash incentives for unused electricity has the potential to incentivize farmers to reduce electricity consumption and irrigation hours by at least 7.5% and up to 30% without impacting paddy yields.
19 Wang, L.; Zhang, F.; Nepal, Santosh; Xiang, Y.; Tang, H.; Shi, X.; Zeng, C.; Ahmad, I.; Yu, Z. 2023. Response of runoff processes to temperature rise in basins with different glacier ratios in the monsoon-influenced southern Tibetan Plateau. Journal of Hydrology: Regional Studies, 45:101299. [doi: https://doi.org/10.1016/j.ejrh.2022.101299]
River basins ; Runoff ; Temperature ; Glaciers ; Monsoons ; Forecasting / Asia / Tibetan Plateau / Karuxung River Basin / Dudh Koshi River Basin / Arun River Basin / Gandaki River Basin / Lhasa River Basin
(Location: IWMI HQ Call no: e-copy only Record No: H051663)
https://www.sciencedirect.com/science/article/pii/S2214581822003123/pdfft?md5=aad81fb593686cfca687574039f2915b&pid=1-s2.0-S2214581822003123-main.pdf
https://vlibrary.iwmi.org/pdf/H051663.pdf
https://vlibrary.iwmi.org/pdf/H051663.pdf
(9.56 MB) (9.56 MB)
Study region: River basins with glacier ratios ranging from 1.8% to 20.7% in the monsoon-influenced southern Tibetan Plateau.
Study focus: The response of runoff processes in basins with different glacier ratios under global warming of 1.5 C and 2 C was explored based on SPHY (Spatial Processes in Hydrology) model and GCMs (General Circulation Models).
New hydrological insights for the region: More prominent temperature and precipitation changes were observed in the monsoon-influenced southern Tibetan Plateau compared with the global averages. With increasing temperature and precipitation, the total runoff and glacier runoff of these basins showed increasing trends under global warming of 1.5 C and 2 C. Compared with the baseline period (1985–2014), increases were observed in the total runoff (1.7–20.6%), base flow (2.8–8.3%), glacier runoff (8.1–35.9%), and rainfall runoff (6.0–36.0%) of these basins. In contrast, snowmelt runoff decreased (- 28.3% - - 4.3%). Therefore, relevant management and allocation of water resources may be required. The hydrological regulation function of glaciers was found to be strongly correlated with glacier ratio. In general, the hydrological regulation function of glaciers would decrease in the future along with warming induced glacier retreat. These findings would help deepen the understanding of runoff processes on the Tibetan Plateau and other alpine regions, thus providing a scientific basis for water resources management under climate change.
Study focus: The response of runoff processes in basins with different glacier ratios under global warming of 1.5 C and 2 C was explored based on SPHY (Spatial Processes in Hydrology) model and GCMs (General Circulation Models).
New hydrological insights for the region: More prominent temperature and precipitation changes were observed in the monsoon-influenced southern Tibetan Plateau compared with the global averages. With increasing temperature and precipitation, the total runoff and glacier runoff of these basins showed increasing trends under global warming of 1.5 C and 2 C. Compared with the baseline period (1985–2014), increases were observed in the total runoff (1.7–20.6%), base flow (2.8–8.3%), glacier runoff (8.1–35.9%), and rainfall runoff (6.0–36.0%) of these basins. In contrast, snowmelt runoff decreased (- 28.3% - - 4.3%). Therefore, relevant management and allocation of water resources may be required. The hydrological regulation function of glaciers was found to be strongly correlated with glacier ratio. In general, the hydrological regulation function of glaciers would decrease in the future along with warming induced glacier retreat. These findings would help deepen the understanding of runoff processes on the Tibetan Plateau and other alpine regions, thus providing a scientific basis for water resources management under climate change.
20 Mukherjee, J.; Ghosh, Surajit. 2023. Decoding the vitality of earth observation for flood monitoring in the Lower Godavari River Basin, India. Journal of the Geological Society of India, 99(6):802-808. [doi: https://doi.org/10.1007/s12594-023-2387-9]
Floods ; Monitoring ; Earth observation satellites ; River basins ; Datasets ; Stream flow ; Forecasting ; Rainfall ; Monsoons ; Climate change ; Satellite imagery / India / Lower Godavari River Basin
(Location: IWMI HQ Call no: e-copy only Record No: H052095)
(2.44 MB)
The entire Indian subcontinent experienced devastating floods in the year 2022. The central section of the Godavari river basin (GRB) received torrential rainfall from the southwest monsoon during the second week of July 2022. This study exhibits how Earth observation (EO) datasets and cloud platforms like Google Earth Engine (GEE) can be used for swift, lucid and accurate decoding of the flood inundation signatures. Geospatial analysts can estimate concurrent floods using high-resolution C-band SAR/Sentinel-1 images, gridded precipitation and streamflow forecast datasets. The GPM (IMERG) precipitation data showed an incremental trend with prime hotspots, rainfall dissemination and retrieval from 01–20 July 2022 in the mid-GRB. The flood inundation layers were derived based on Otsu’s method with selective topographic conditions from Sentinel-1 in GEE. Five significant flood affected case sites were identified in the lower GRB from Kothapalli to Yanam town, where the Godavari river meets the Bay of Bengal. Large stretches of agricultural lands were found to be inundated, resulting in extensive economic losses. Such flooded farmlands surrounding Kothapalli, Bhadrachalam, Kunavaram, Polavaram and Yanam towns were estimated as 60, 91, 86, 170 and 142 km2 on 16 and 21 July 2022, respectively. The results were validated and cross-verified using bulletins and maps issued by various national agencies. Hence, EO, GEE and cloud analytical techniques are modern untapped potential e-assets vital for incorporation in policy frameworks helping disaster managers with comprehensive flood condition analysis.
Powered by DB/Text WebPublisher, from
