Leading the way: Creating dialogue on the water-food-energy nexus
Across the world, the assessment and sustainable management of water resources is a major issue fraught with challenges.
This is even more so for the regional basins of South Asia where population pressure, uncertainty about water availability and the effects of climate variability and climate change put unprecedented stress on these vital water resources.
Solutions to these challenges are being sought that use science and models to contribute data and information to policy and program decisions where knowledge is limited.
CSIRO’s Dr Sreekanth Janardhanan, Dr Jorge Peña Arancibia and Dr Mainuddin Mohammed, co-convened a session at the Asia Oceania Geosciences Society 2019 Conference inviting submissions from researchers addressing challenges in the Water-Energy-Food Nexus to enable greater collaboration and networking between researchers and organisations.
The session was a great success with several presentations discussing issues in the Ganga, Brahmaputra, Indus, Mekong, Yellow and African basins and generating much positive feedback from participants.
Conference attendees and presenters.
The conference session brought together researchers in integrated water resources use and management to share their research, this knowledge sharing enables the learning of new perspectives on issues, problem solving and stimulates innovation. Continued support of network growth and cross-collaboration are important in addressing the global issue of water security and sustainably managing water resources for a water secure future for South East Asia.
CSIRO presented two case studies, Dr Jorge Peña Arancibia presented about the impact of irrigation on groundwater levels in Bangladesh and Dr J Indu, collaborator from IIT Bombay presented about the use of climate change and water models to predict the future water availability on behalf of Dr Janardhanan
Case study 1: Impact of irrigation on groundwater levels
The northwest region of Bangladesh is the largest irrigated area in the country. This region supplies Bangladesh with 35% of all dry season rice – Boro rice and more than 60% of wheat and maize, helping to achieve food security for about 165 million people. Declining groundwater levels are resulting in the need to deepen wells which in turn increases the cost of water pumping, affecting drinking and irrigation water supply.
The project team aimed to determine the main causes of Bangladesh’s declining groundwater levels via hydrological modelling. By capturing the long-term changes in irrigation using remote sensing and crop survey data, and then analysing rainfall, evapotranspiration and groundwater levels, the team found that several factors were linked to declining groundwater levels. These included, reduced rainfall, declining deep drainage and increased pumping for irrigation and the degree of importance of these factors varied across the region.
Such variety of contributing factors highlights the need for a multi-pronged approach to addressing the root causes of groundwater decline and a single policy or management change like increasing the use of surface water for irrigation will not be enough to reverse diminishing groundwater.
Case study 2: Predicting climate change stressor impact on river basins
Groundwater extraction in India accounts for (a huge) 25% of global groundwater extraction and is used in around 65% of irrigated agriculture in India.
More than 50% of districts in India are facing declining groundwater that is expected to be exacerbated by the effects of climate change.
Decisions about the management and regulation of groundwater must be supported by knowledge and evidence of the status, trends and future conditions of the groundwater resource. There is a relatively modest amount of conventional groundwater monitoring data available in most regions in India.
To understand the amount of available groundwater, water assessments it is best to integrate the diverse and extensive data and knowledge from a range of disciplines including remote sensing, hydrology, climate forecasting and agricultural systems modelling to inform decision making.
The project team successfully developed and tested an integrated approach using regional scale land surface and groundwater models to understand the groundwater resource in the Ganga Basin. Model inputs were further refined with local data sets. Using this modelling approach the low, middle and high ranges of groundwater levels can be forecast for future conditions such as climate change and increased irrigation demand, creating more data and knowledge for water managers in the sustainable management of the groundwater resource.
This news post, designed and implemented by CSIRO, contributes to SDIP and is supported by the Australian aid program.
SDIP Phase 2 aims to improve the integrated management of water, energy and food in the Himalayan river basins, addressing climate risk and the interests of women and girls. It seeks to:
- strengthen practices for regional cooperation
- generate and use critical new knowledge to enhance regional cooperation
- improve the regional enabling environment for private sector engagement.