A novel partitioning of gross primary production and water use efficiency for sustaining water and food security using Budyko hypothesis.

This study coupled the green water and blue water accounting with the existing standard Budyko framework and Fu's 1-parameter Budyko framework to diagnose the basin hydrological behavior. Both Budyko frameworks were employed to determine green water consumption (ETGreen) and blue water consumption (ETBlue) which, in turn, were used to map the blue water index (BWI) hotspots and green water index (GWI) bright spots. The relative contributions of green water and blue water were quantified for sustaining water and food security. A new methodology is proposed using BWI and GWI for partitioning the Gross Primary Production (GPP) and Water Use Efficiency (WUE) into GPPBlue, GPPGreen and WUEBlue and WUEGreen. The methodology was applied to five sub-basins of the Central Godavari River Basin (CGRB): Purna, Dhalegaon, GR Bridge, Yeli and Delta. Results showed that all five basins exhibited larger deviations from the theoretical Budyko curve of Fu's 1-parameter Budyko framework than did the standard Budyko framework and the Dhalegaon basin showed the largest deviations. The partitioning of GPP and WUE by the proposed methodology showed that the proportion of GPPGreen to the total GPP was much higher than that of the GPPBlue. Similarly, the proportion of WUEGreen to WUE was more than that of WUEBlue. The mapping of GPPBlue and GPPGreen, and WUEBlue and WUEGreen showed that the Delta and Yeli basins had the highest values of both GPPGreen & GPPBlue and WUEBlue and WUEGreen (bright spot basins) and the Dhalegaon and parts of GR Bridge basin had the lowest values (hot spot basins). The proposed partitioning of GPP and WUE will help identify the relative contributions of green water and blue water (for managing agricultural waters) and formulate agronomical and engineering practices for stakeholders and policy makers for increasing the overall WUE and GPP to sustain water and food security.

Drought risk assessment on the eastern part of Indian peninsula-a study on Purulia district, West Bengal.

This study focuses on measuring the spatial nature of drought risk which is conceived as the product of drought severity, drought vulnerability, and drought exposure in the Purulia district, located in the eastern part of the Indian peninsula. Drought severity is measured using the Standard Precipitation Index and drought vulnerability is calculated as the average condition of meteorological, hydrological, agricultural, and socio-economic drought. The drought types and drought exposure conditions are the outcome of multi-criteria analysis where the Fuzzy Analytical Hierarchy Process is used for assigning weights to the respective parameters and the Analytical Hierarchy Process is used for determining the class ranks. 31.46% of the total district area has registered moderate to high and high vulnerability to drought situations, while 16.57% of the entire district area has been found moderate to high and highly exposed to drought situations. Similarly, 39.39% of the district's total area is under a significant drought risk. Blocks like Barabazar (75.49%), Jhalda-I (71.85%), and Purulia-II (52.66%) have the majority of their area under extreme drought risk conditions. The modeled outcome of drought vulnerability was found significant while being tested with phenomena highly correlated to drought events, land surface temperature, and aridity index. The computed spatial profile of the districts' drought risk condition is of substantial help for the policymakers in preparing effective drought mitigation measures to restrict drought impacts reasonably.

Overview of terrestrial water storage changes over the Indus River Basin based on GRACE/GRACE-FO solutions.

Water resources are under severe stress in the highly populated Indus River Basin due to the increased consumption of water across different sectors and climate change. Coping with these challenges, requires a clear understanding on hydrological processes and anthropogenic activities, and how these are influencing recharging and spatiotemporal availability of groundwater in the basin. The present study aims to investigate the natural and anthropogenic impact on Terrestrial Water Storage (TWS) over the Indus River Basin by using a series of statistical methods and the observation data from the Gravity Recovery and Climate Experiment (GRACE) and Follow-On (GRACE-FO). Our results show that (i) TWS Anomaly (TWSA) experienced a significant decrease from 2002 to 2020, particularly in the MUIP; (ii) the UIB showed a weak decreasing trend in TWSA as a result of the accelerated glacier melting; (iii) there was significant loss of groundwater (1.57 mm/month) caused by ineffective water management and over-exploitation; and (iv) assisted by favorable meteorological conditions, the precipitation presented a positive trend against the weakness of the Westerlies, which exerted the positive influence on TWSA.