The Impact Of Global Change On Water Scarcity And Its Mitigation
Event Type: Seminar
Event Date: 01 Feb 2018
Venue: ASE 3D Viz Laboratory Room (N2-B1c-16c)
Speaker: Junguo Liu
About the speaker:
Dr. Junguo Liu is a professor in the School of Environmental Science and Engineering, at Southern University of Science and Technology (SUSTech) in China, and a research scholar at the International Institute for Applied Systems Analysis (IIASA) in Austria. His main research interests include hydrology and water resources management, global environmental change, and ecological restoration. He has earned an excellent international reputation through his contributions to the fields of water resources research and eco-hydrological restoration.
About the event:
Water scarcity has become a major constraint to socio-economic development and a threat to livelihood in increasing parts of the world. In this talk, water scarcity will be discussed on two scales. On the global scale, water scarcity is simulated by a scenario analysis using monthly water resources simulations at a 0.5 degree (About 50 km at the equator) spatial resolution for the period 1971–2010 reflecting conditions of no human interventions (NHI) and time-varying human interventions (NHI). Our results show that HI drastically change the critical dimensions of water scarcity, aggravating water scarcity for 8.8% (7.4-16.5%) of the global population but alleviating it for another 8.3% (6.4-15.8%). Positive impacts of HI mostly occur upstream, whereas HI aggravate water scarcity downstream; HI cause water scarcity to travel downstream. Compared with those regions with a significant trend in climate change impacts on water resources, affecting on average 12.1% of the global population, HI impacts contributed or dominated the change in water resources over time in a significant part of the globe, inhabited by 8.2% and 1.5% of the global population, respectively.
On the national scale, we aim to answer the question whether the water redistributions through virtual and physical forms in China can be effective in mitigating regional water stress. Our analysis shows that both physical and virtual water flows do not play a major role in mitigating water stress in the water-receiving regions but exacerbate water stress for the water-exporting regions of China. Improving water use efficiency is key to mitigating water stress, but the efficiency gains will be largely offset by the water demand increase caused by continued economic development. We conclude that much greater attention needs to be paid to water demand management rather than the current focus on supply-oriented management. In addition, “gray” infrastructure as the conventional way to manage water is often capital intensive and may address only a few water problems. There is renewed focus on “green” infrastructure, which can be more flexible and cost effective for providing benefits besides water provision. Supplementing or integrating gray infrastructure with biophysical systems is critical to meet current and future water needs.