Murugesu Sivapalan

In honor of Sivapalan's contributions to the development of hydrologic science the International Association of Hydrological Sciences (IAHS) established the Sivapalan Young Scientists Travel Award (SYSTA) in 2018.

From about 2010, Sivapalan turned his attention to the problem of predictions under change, especially human-induced changes to the hydrologic systems. Through a series of meetings, he brought the hydrologic community together to develop a forward-looking agenda to deal with predictions under change. In 2011 he and his colleagues launched the sub-field of socio-hydrology as a science that deals with the two-way feedback between humans and water. Socio-hydrology presents a coevolutionary view of hydrologic systems and explores the relationship between water, human activities, landscapes, and climate. The launch of socio-hydrology coincided with the launch of the Panta Rhei: Change in Hydrology and Society, another global, decadal (2013–22) initiative of the International Association of Hydrological Sciences in which once again Sivapalan played a leading role. He traveled around the world, establishing international collaborations in Australia, China, and Europe, and promoting socio-hydrologic thinking. For his contributions to socio-hydrology and his leadership in promoting the field around the world he was awarded the Prince Sultan Bin Abdulaziz International Prize for Water (PSIPW) (Creativity Prize).

Sivapalan joined the University of Illinois at Urbana-Champaign in 2005. He became Chester and Helen Siess Endowed Professor of Civil and Environmental Engineering in April 2015.

Around 2001, Sivapalan turned his attention to the problem of Predictions in Ungauged Basins (PUB). He introduced the idea of PUB to the International Association of Hydrological Sciences (IAHS), which launched PUB as a global, decadal (2003–2012) initiative, with Sivapalan as the founding chair. Sivapalan wrote the PUB science plan, organized several workshops and conferences, and traveled around the world to promote it and mobilize the community. Apart from its practical value, Sivapalan saw PUB as providing the basis for advancing a unified theoretical basis for catchment hydrology. The culmination of PUB was the publication of the landmark synthesis book Runoff Predictions in Ungauged Basins (Blöschl et al., 2013) by Cambridge University Press, in which Sivapalan served as an editor.

From1999 to 2008, Sivapalan focused on the development of hydrological models at the catchment scale. He approached the problem from the bottom up and top down. He and his doctoral student Paolo Reggiani proposed a/the thermodynamic theory framework to formulate balance equations for mass, momentum, and energy at the catchment scale and associated constitutive theory and closure relations that he introduced as a way to develop physically based hydrologic models of appropriate complexity and fidelity over what he called the representative elementary watershed (REW) scale. In parallel, he and students Chatchai Jothityangkoon and Darren Farmer proposed an alternative top-down, data-based methodology for the systematic development of models of appropriate complexity by focusing on reproducing signatures of hydrologic variability over a range of timescales.

During his PhD studies and in the ten years afterward (1989–1998), Sivapalan devoted himself to research on scale issues in hydrological predictions. This research led successively to several new concepts: hydrologic scale concept that covers "hydrologic process scale", "observation scale" and "modeling scale" temporally and spatially; hydrological similarity concept that connects the watershed heterogeneity and flood frequency analyses; the representative elementary area (REA) concept that deals with the effects of small scale spatial variability of catchments in an aggregate way; meta channel concept which collapses the stream network of a catchment into a single channel with effective hydraulic properties. His review paper Career path Research achievements Phase 1. Extrapolation Across Scales: Scale Issues in Hydrologic Predictions with Günter Blöschl on scale issues in hydrological modeling has now become a classic. He organized successful workshops on scale issues in Robertson, Australia, in 1993 and in Krumbach, Austria, in 1996, which had a major impact on the field.

In 1988 Sivapalan migrated to Australia, and between 1988 and 2005, he worked at the Centre for Water Research, Department of Environmental Engineering in the University of Western Australia, joining as a lecturer (1988) and subsequently being promoted to senior lecturer (1992), associate professor (1995) and professor (1999).

Sivapalan had his high school education at Hartley College, Point Pedro. After school, he joined the University of Ceylon, Peradeniya, and graduated from its successor, the University of Sri Lanka Peradeniya campus in 1975 with a BSc. degree in civil engineering. He later received an MEng degree in water resources engineering from the Asian Institute of Technology in Bangkok, Thailand in 1977. Subsequently, he obtained the M.A. (1983) and PhD (1986) degrees in civil engineering, with a specialization in hydrology from Princeton University. In 2012, Sivapalan was awarded the Honorary Doctorate by Delft University of Technology.

In 1975, Sivapalan worked briefly at the Faculty of Engineering, University of Sri Lanka (Peradeniya campus) as an instructor in civil engineering. Later in 1977, he worked as a research associate in the Division of Water Resources Engineering Asian Institute of Technology. Between 1978 and 1981, he worked as a geotechnical engineer for Rocks & Stones Ltd., a consulting engineering company based in Ibadan, Nigeria. Between 1986 and 1988, upon completion of his PhD, Sivapalan served as a post-doctoral research associate at Princeton University's department of civil engineering and operations research.

Sivapalan was born on 19 April 1953, in Karaveddy in northern Sri Lanka. He was the son of Sangarapillai and Umadevy Murugesu. He is married to Banumathy. They have two sons: Mayuran and Kavin.