Pitt | Swanson Engineering
Liang, Xu
Civil & Environmental Engr
Publication Role 
Water Resources Research Associate Editor

PhD in Hydrology and Water Resources, University of Washington, 1994

Postdoctoral Training in Postdoctoral Researcher/Research Associate, Princeton University, 1994-1996

Dr. Liang’s fundamental research interests are: (1) to discover fundamental laws that govern water and energy cycles, (2) to investigate how the water and energy cycles affect the health of our environment and ecological systems, and how they influence the transport and cycling of nutrients and pollutants at different scales, such as at local, regional, continental, and global scales, and (3) how to improve hydrological forecasting of extreme events including flooding and droughts.

Dr. Liang’s research work includes (1) land surface modeling, (2) hydro-informatics with machine learning methods and (3) cyber-infrastructure for earth science, and applications of sensors and wireless sensor network for environmental, ecological, and hydrological systems.

Recipient of 2016 Chancellor’s Distinguished Research Award (senior category), University of Pittsburgh, Pittsburgh, PA.

Fellow, American Meteorological Society (AMS)

Recipient of the 2014 Carnegie Science Environmental Award.

Chang Jiang Chair Professor, China's Ministry of Education and Hongkong Li Ka-Shing Foundation, 2009 – 2012.

Recipient of two award certificates for “the creative development of technically significant software” entitled “MODIS Atmosphere Level-3 Algorithm Software – Level 3 Atmosphere 8-day and Monday, CMG”, NASA, October 2003.

Recipient of Hellman Foundation Junior Faculty Research Award, Univ. of California at Berkeley, 2000. This award is to “support substantially the research of promising assistant professors who show capacity for great distinction in their research” ( http://vpf.berkeley.edu/hellman-fellows-fund).

Three of her Ph.D. students (Drs. T. Davis, L. Parada, and M. Huang) received student awards from AGU (2009) and UC Berkeley (2002, 2003, and 2004), respectively.

Luo, X., X. Liang, and J.-S. Lin, Plant transpiration and groundwater dynamics in water-limited climates: Impacts of hydraulic redistribution, Water Resour. Res., 52, doi:10.1002/2015WR017316 (22 pages), 2016.

Prentice, I.C., X. Liang, B.E. Medlyn, and Y.-P. Wang, Reliable, robust and realistic: the three R’s of next-generation land-surface modeling, Atmos. Chem. Phys., 15, doi:10.5194/acp-15-5987-2015, 5987–6005, 2015.

Wang, S., and X. Liang, A Parameter Estimation Framework for Multiscale Kalman Smoother Algorithm in Precipitation Data Fusion, Water Resour. Res., 50, 8675-8693, doi:10.1002/2013WR014942, 2014.

Navarro, M., T.W. Davis, G. Villalba, Y. Li, X. Zhong, N. Erratt, X. Liang, and Y. Liang, Towards long-term multi-hop WSN deployments for environmental monitoring: An experimental network evaluation, J. Sens. Actuator Netw., 4, 297-330, doi:10.3390/jsan3040297, 2014.

Luo, X., X. Liang, and H.R. McCarthy, VIC+ for Water-limited Conditions: A Study of Biological and Hydrological Processes and Their Interactions in Soil-Plant-Atmosphere Continuum, Water Resour. Res., 49, doi:10.1002/2012WR012851 (22 pages), 2013.

Davis, T.W. and X. Liang, The Potential Use of Soil Moisture Sensors for Observing Hydraulic Redistribution Characteristics, J. of Water Resour. & Hydraulic Eng., 2(3), 84-91, 2013.

Wen, Z., X. Liang, and S. Yang, A new multiscale routing framework and its evaluation for land surface modeling applications, Water Resour. Res., W08528, doi:10.1029/2011WR011337, (16 pages), 2012.

Davis, T.W., C-M. Kuo, X. Liang, and P-S Yu, Sap flow sensors: construction, quality control and comparison, Sensors, 12, doi:10.3390/s120100954, 954-971, 2012c.

Davis, T., X. Liang, M. Navarro, D. Bhatnagar, and Y. Liang, An Experimental Study of WSN Power Efficiency: MICAz networks with XMesh, in special issue of Smart Sensor Networks: Theory and Practice -- International Journal of Distributed Sensor Networks, doi:10.1155/2012/358238, (14 pages), 2012b.

Davis, T.W., X. Liang, C-M. Kuo, and Y. Liang, Analysis of power characteristics for sap flow, soil moisture and soil water potential sensors in wireless sensor networking systems, IEEE Sensors Journal, Vol. 12, No. 6, 1933-1945, 2012a.

Salas, D., X. Liang, and Y. Liang, A systematic approach for hydrological model couplings, Int. J. Communications, Network and System Sciences, 5, 343-352, 2012.

Xu, W., Z. Niu, and X. Liang, Experimental investigation of the scouring of quake dams during dam-break, J. of Earthquake and Tsunami, 5(5), DOI: 10.1142/S1793431111001170, 429-444, 2011.

Wang, S., X. Liang, and Z. Nan, How much improvement can precipitation data fusion achieve with a Multiscale Kalman Smoother-based framework?”, Water Resour. Res., 47, W00H12, doi:10.1029/2010WR009953, (18 pages), 2011.

Ferguson, I.M, P.B. Duffy, T.J. Phillips, X. Liang, J.A. Dracup, S. Schubert, and P. Pegion, Non-stationarity of the signal and noise characteristics of seasonal precipitation anomalies, Climate Dynamics, Vol. 36, No. 3-4, 739-752, DOI 10.1007/s00382-010-0850-y, 2011.

Leung, L.R., M. Huang, Y. Qian, and X. Liang, Climate-Soil-Vegetation control on groundwater table dynamics and its feedbacks in a climate model, Climate Dynamics, Vol. 36, No. 1-2, 57-81, DOI 10.1007/s00382-010-0746-x, 2011.

Nan, Z., S. Wang, X. Liang, T. Adams, W. Teng, and Y. Liang, Analysis of spatial similarities between NEXRAD Stage III and LDAS Combo precipitation data products, IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 3(3), 371-385, 2010.

Parada, L.M., and X. Liang, A novel approach to infer streamflow signals for ungauged basins, Advances in Water Resources, 33, 372-386, 2010.

Ravindran, N., Y. Liang, and X. Liang, A labeled-tree approach to semantic and structural data interoperability applied in hydrology domain, Information Sciences, 180, 5008-5028, 2010.

Huang, M., X. Liang, and L.R. Leung, A generalized subsurface flow parameterization considering subgrid spatial variability of recharge and topography, J. Hydrometeorology, 9, 1151-1171, DOI: 10.1175/2008JHM936.1, 2008.

Parada, L.M., and X. Liang, Impacts of spatial resolutions and data quality on soil moisture data assimilation, J. Geophys. Res., 113, D10101, doi:10.1029/2007JD009037, (17 pages), 2008.

Liang, Y., and X. Liang, Improving signal prediction performance of neural networks through multiresolution learning approach, IEEE Transactions on Systems, Man and Cybernetics –Part B, 36(2), 341-352, 2006.

Jeong, S., Y. Liang, and X. Liang, Design of an integrated data retrieval, analysis, and visualization system: Application in the hydrology domain, Environmental Modelling & Software, 21(12), 1722-1740, 2006.

Huang, M., and X. Liang, On the assessment of the impact of reducing parameters and identification of parameter uncertainties for a hydrologic model with applications to ungauged basins, J. Hydrol., 320, 37-61, 2006.

Liang, X. with Q. Duan et al., Model Parameter Estimation Experiment (MOPEX): An overview of science strategy and major results from the second and third workshops, J. Hydrol., 320, 3-17, 2006.

Parada, L. M., and X. Liang, Optimal multiscale Kalman filter for assimilation of near-surface soil moisture into land surface models, J. Geophys. Res., 109(D24), doi:10.1029/2004JD004745, (21 pages), 2004.

Guo, J., X. Liang, and L.R. Leung, A new multi-scale flow network generation scheme for land surface models, Geophys. Res. Letters, 31, L23502, doi:10.1029/2004GL021381, (4 pages), 2004b.

Zhou, S., X. Liang, J. Chen, and P. Gong, An assessment of the VIC-3L hydrological model for the Yangtze River basin based on remote sensing: a case study of the Baohe River basin, Canadian Journal of Remote Sensing, 30(5), 840-853, 2004.

Yuan, F., Z.H. Xie, Q. Liu, H.W. Yang, F.G. Su, X. Liang, and L.L. Ren, An application of the VIC-3L land surface model and remote sensing data in simulating streamflow for the Hanjiang River basin, Canadian Journal of Remote Sensing, 30(5), 680-690, 2004.

29. Guo, J., X. Liang, and L. R. Leung, Impacts of different precipitation data sources on water budgets, J. Hydrol., 298, 311-334, 2004a.

Liang, X., J. Guo, and L. R. Leung, Assessment of the effects of spatial resolutions on daily water flux simulations, J. Hydrol., 298, 287-310, 2004.

Xie, Z.H., F.G. Su, X. Liang, Q.C. Zeng, Z.C. Hao, and Y.F. Guo, Applications of a surface runoff model with Horton and Dunne runoff for VIC, Advances in atmospheric sciences, 20(2), 165-172, 2003.

Sivapalan M., K. Takeuchi, S.W. Franks, V.K. Gupta, H. Karambiri, V. Lakshmi, X. Liang, J.J. McDonnell, E.M. Mendiondo, P.E. O'Connell, T. Oki, J.W. Pomeroy, D. Schertzer, S. Uhlenbrook, E. Zehe, IAHS decade on Predictions in Ungauged Basins (PUB), 2003-2012: Shaping an exciting future for the hydrological sciences, Hydrological Sciences Journal, 48 (6), 857-880, 2003.

Parada, L. M., and X. Liang, A downscaling framework for L band radiobrightness temperature imagery, J. Geophys. Res., 108(D22), 8863, doi:10.1029/2003JD003637, (15 pages), 2003.

Huang, M., X. Liang, and Y. Liang, A transferability study of model parameters for the variable infiltration capacity land surface scheme, J. Geophys. Res., 108(D22), 8864, doi: 10.1029/2003JD003676, (15 pages), 2003.

Parada, L. M., and X. Liang, A stochastic modeling approach for characterizing the spatial structure of L band radiobrightness temperature imagery, J. Geophys. Res., 108(D22), 8862, doi:10.1029/2003JD003567, (14 pages), 2003.

Liang, X., and J. Guo, Intercomparison of land surface parameterization schemes: Sensitivity of surface energy and water fluxes to model parameters, J. Hydrol., 279, 182-209, 2003.

Liang, X., Z. Xie, and M. Huang, A new parameterization for surface and groundwater interactions and its impact on water budgets with the variable infiltration capacity (VIC) land surface model,J. Geophys. Res., 108(D16), 8613, doi: 10.1029/2002JD003090, (17 pages), 2003.

Liang, X., and Z. Xie, Important factors in land-atmosphere interactions: Surface runoff generations and interactions between surface and groundwater, Global & Planetary Change, 38(1-2), 101-114, July 2003.

Parada, L. M., J. P. Fram, and X. Liang, Multi-resolution calibration methodology for hydrologic models: Applications to a sub-humid catchment, in Advances in Calibration of Watershed Models, Q. Duan, H. Gupta, S. Sorooshian, A. Rousseau, and R. Turcotte, Eds., Water Science and Application Series, 6, American Geophy. Union, 197-211, 2003.

Liang, X., and Z. Xie, A new surface runoff parameterization with subgrid-scale soil heterogeneity for land surface models, Advances in Water Resources, 24(9-10), 1173-1193, November-December 2001.

Liang, X., E.F. Wood, and D.P. Lettenmaier, Reply to comments by Lohmann (2001) on Modeling Ground Heat Flux in Land Surface Parameterization Schemes, by Liang, Wood, and Lettenmaier (1999),J. Geophys. Res., 106(D16), 17,893-17,896, August 2001.

Jackson, C.R., S.J. Burges, X. Liang, K.M. Leytham et al., Development and application of simplified continuous hydrologic modeling for drainage design and analysis, in Land Use and Watersheds: Human Influence on Hydrology and Geomorphology in Urban and Forest Areas, M. Wigmosta and S.J. Burges, Eds., Water Science and Application Series, 2, American Geophy. Union, 39‑58, 2001.

Liang, X. with A.J. Pitman et al., Key results and implications from phase 1(c) of the Project for Intercomparison of Land-surface Parameterization Schemes, Clim. Dynamics, 15(9), 673-684, September 1999.

Abdulla, F.A., D.P. Lettenmaier, and X. Liang, Estimation of the ARNO model baseflow parameters using daily streamflow data, J. Hydrol., 222(1-4), 37-54, September 1999.

Liang, X., E.F. Wood, and D.P. Lettenmaier, Modeling ground heat flux in land surface parameterization schemes, J. Geophys. Res., 104(D8), 9581-9600, April 1999.

Lohmann, D., D.P. Lettenmaier, X. Liang, E.F. Wood et al., The project for intercomparison of land-surface parameterization schemes (PILPS) phase-2c Red-Arkansas river basin experiment: 3. Spatial and temporal analysis of water fluxes, Global and Planetary Change,19(1-4), 161-179, December 1998.

Liang, X., E.F. Wood, D.P. Lettenmaier et al., The project for intercomparison of land-surface parameterization schemes (PILPS) phase-2c Red-Arkansas river basin experiment: 2. Spatial and temporal analysis of energy fluxes, Global and Planetary Change, 19(1-4), 137-159, December 1998.

Wood, E.F., D.P. Lettenmaier, X. Liang, D. Lohmann, A. Boone et al., The project for intercomparison of land-surface parameterization schemes (PILPS) phase-2c Red-Arkansas river basin experiment: 1. Experiment description and summary intercomparisons, Global and Planetary Change, 19(1-4), 115-135, December 1998.

Liang, X. with W. Qu et al., Sensitivity of latent heat flux from PILPS land-surface schemes to perturbations of surface air temperature, J. Atmos. Sci., 55(11), 1909-1927, June 1998.

Peters-Lidard, C.D., E. Blackburn, X. Liang, and E.F. Wood, The effect of soil thermal conductivity parameterization on surface energy fluxes and temperatures, J. Atmos. Sci., 55(7), 1209-1224, April 1998.

Liang, X., with T.H. Chen et al., Cabauw experimental results from the project for intercomparison of land-surface parameterization schemes, J. Clim., 10(6), 1194-1215, June 1997.

Nijssen, B., D.P. Lettenmaier, X. Liang, S. Wetzel, E.F. Wood, Streamflow simulation for continental-scale river basins,Water Resour.Res., 33(4), 711-724, April 1997.

Wood, E.F., D.P. Lettenmaier, X. Liang, B. Nijssen, and S.W. Wetzel, Hydrological modeling of continental-scale basins,Annu. Rev. Earth Planet. Sci., 25, 279-300, 1997.

Liang, X., D.P. Lettenmaier, and E.F. Wood, A one-dimensional statistical dynamic representation of subgrid spatial variability of precipitation in the two-layer variable infiltration capacity model, J. Geophys. Res., 101(D16), 21,403-21,422, September 1996b.

Wetzel, P.J., X. Liang, P. Irannejad, A. Boone, J. Nolhan, Y. Shao, C. Skelly, Y. Xue, and Z. Yang, Modeling vadose zone liquid water fluxes: Infiltration, runoff, drainage, interflow, Global and Planetary Change, 13(1-4), 57-71, June 1996.

Liang, X., E.F. Wood, and D.P. Lettenmaier, Surface soil moisture parameterization of the VIC-2L model: Evaluation and modifications, Global and Planetary Change, 13(1-4), 195-206, June 1996a.

Liang, X., D.P. Lettenmaier, E.F. Wood, and S.J. Burges, A simple hydrologically based model of land surface water and energy fluxes for general circulation models, J. Geophys. Res., 99(D7), 14,415-14,428, July 1994.