# Vijay Gupta

## Research Interests

Vijay K. Gupta was a professor emeritus in the Department of Civil, Environmental and Architectural Engineering, and a fellow emeritus of CIRES. Vijay has widely published in major research journals in hydrologic and atmospheric sciences, applied mathematics, probability theory, and nonlinear processes in geophysics. Soon after completing his PhD in 1973, Vijay embarked upon highly interdisciplinary collaborative research. From the onset, he recognized the fundamental importance of scale. It became a pervasive theme in all his work, which has uniquely ranged from the molecular to the planetary scales. His life-long collaboration with colleagues from many different disciplines and outstanding graduate students led to establishing the nonlinear geophysical foundations of floods in river networks on multiple space and time scales. The Iowa Flood Center at the University of Iowa is building on these foundations with new applications. Vijay modernized and developed a new graduate course over a decade titled “introduction to multi-scale hydrology”, which has continued to be taught at the University of Iowa. Vijay served on the editorial boards of prominent international journals, and on important national committees. He was invited as a keynote speaker in several national and international conferences and workshops, and gave seminars at well-known universities in USA, Asia, Latin America and Europe. Sadly, Vijay died in March of 2022.

## Current Research

Publications Before Retirement (2007 - 2012)

Furey, P.R. and Gupta, V. K. (2007), Diagnosing peak-discharge power laws observed in rainfall–runoff events in Goodwin Creek experimental watershed, Advances in Water Resources, 30 2387–2399.

Gupta, V. K., Troutman, B. M., and Dawdy, D. R. (2007), Towards a nonlinear geophysical theory of floods in river networks: an overview of 20 years of progress, Nonlinear dynamics in geosciences, edited by A. A. Tsonis and J. B. Elsner, pp. 121–151, doi:10.1007/978-0- 387-34918-3_8, Springer, New York.

McConnell, M., and Gupta, V. K. (2008). "A proof of the horton law of stream numbers for the Tokunaga model of river networks." Fractals, 16(03), 227-233.

Mandapaka, P. V., Krajewski, W. F., Mantilla, R., and Gupta, V. K. (2009). "Dissecting the effect of rainfall variability on the statistical structure of peak flows." Advances in Water Resources, 32(10), 1508-1525.

Gupta, V. K., Mantilla, R., Troutman, B. M., Dawdy, D., and Krajewski, W. F. (2010). "Generalizing a nonlinear geophysical flood theory to medium-sized river networks." Geophysical Research Letters, 37(11), L11402-L11402.

Mantilla, R., Troutman, B. M., and Gupta, V. K. (2010). "Testing statistical self-similarity in the topology of river networks." Journal of Geophysical Research: Earth Surface, 115(F3), F03038.

Mantilla, R., Gupta, V. K., and Troutman, B. M. (2011). "Scaling of peak flows with constant flow velocity in random self-similar networks." Nonlinear Processes in Geophysics, 18(4), 489-502.

Dunn, W., Milne, B., Mantilla, R., and Gupta, V. (2011). "Scaling relations between riparian vegetation and stream order in the Whitewater River network, Kansas, USA." Landscape Ecol, 26(7), 983-997.

Mantilla, R., Gupta, V. K., Troutman, B. M. (2012). Extending generalized Horton laws to test embedding algorithms for topologic river networks, Geomorphology, 151–152, 13–26.

Publications After Retirement (2012 - 2017)

Vijay completed and published the most challenging papers that he worked on for decades:

A. S. Sharma, D. N. Baker, A. Bhattacharyya, A. Bunde, V. P. Dimri, H. K. Gupta, V. K. Gupta, S. Lovejoy, I. G. Main, D. Schertzer, H. Storch, and N. W. Watkins (2012), Complexity and Extreme Events in Geosciences: An Overview, Geophysical Monograph Series 196 , 1-16, American Geophysical Union.

O. J. Mesa, V. K. Gupta, and P. E. O’Connell, Dynamical System Exploration of the Hurst Phenomenon in Simple Climate Models, Extreme Events and Natural Hazards: The Complexity Perspective, Geophysical Monograph Series 196 , 209-229, American Geophysical Union, 2012.

D. R. Dawdy, V. W. Griffis and V. K. Gupta, Regional Flood Frequency Analysis: How We Got Here and Where We are Going, J. Hydrologic Eng. 17:953-959, 2012.

P. R. Furey, V. K. Gupta, and B. M. Troutman, A top-down model to generate ensembles of runoff from a large number of hillslopes, Nonlin. Processes Geophys., 20, 683–704, 2013.

V. K. Gupta and O. J. Mesa, Horton laws for hydraulic–geometric variables and their scaling exponents in self-similar Tokunaga river networks, Nonlin. Processes Geophys., 21, 1007–1025, 2014.

V. K. Gupta, T. B. Ayalew, R. Mantilla, and W. F. Krajewski, Classical and generalized Horton laws for peak flows in rainfall-runoff events, Chaos, 25, 075408 (2015); doi: 10.1063/1.4922177.

P. Furey, B. M. Troutman, V. K. Gupta, and W. F. Krajewski, Connecting Event-Based Scaling of Flood Peaks to Regional Flood Frequency Relationships, J. Hydrologic Eng. 2016. DOI: 10.1061/(ASCE)HE.1943-5584.0001411

B Milne and V. K. Gupta, Horton Ratios Link Self-Similarity with Maximum Entropy of Eco-Geomorphological Properties in Stream Networks, Entropy (2017), 19, doi10.3390/e19060249

## Honors and Awards

- CUHASI (www.cuahsi.org) honored him with a service award for “outstanding vision and leadership in the development of interdisciplinary research in hydrologic sciences”, 2012
- Robert E. Horton medal of the AGU for outstanding contributions to Hydrology, 2008
- Golden Jubilee Lecture, Dept. of Civil Eng., Indian Inst. Sci., Bangalore, India, 2000
- Fellow of the American Geophysical Union (AGU),1990