top of page


55. Armengol, S.*, H. Ajami, J.S. Acero Triana, J. O. Sickman, L. Ortega. 2024. Isogeochemical Characterization of Mountain System Recharge Processes in the Sierra Nevada, California. Water Resources Research, 60, e2023WR035719.

54. Meles, M.B., S. Bradford, A. Casillas-Trasvina, L. Chen*, G. Osterman, T. Hatch, H. Ajami, O. Crompton, L. Levers, I. Kisekka. 2024. Uncovering the Gaps in Managed Aquifer Recharge for Sustainable Groundwater Management: A Focus on Hillslopes and Mountains. Journal of Hydrology.

53. Meles, M.B., L. Chen*, C. Unkrich, H. Ajami, S. Bradford, J. Šimůnek, D.C. Goodrich. 2024. Computationally Efficient Watershed-Scale Hydrological Modeling: Integrating HYDRUS-1D and KINEROS2 for Coupled Surface-Subsurface Analysis. Journal of Hydrology.

52. Zipper, S., A. Brookfield, H. Ajami, J.R. Ayers, C. Beightel, M.N. Fienen, T. Gleeson,  J. Hammond,  M. Hill,  A.D. Kendall,  B. Kerr,  D. Lapides,  M. Porter,  S. Parimalarenganayaki,  M.M. Rohde,  C. Wardropper. 2024. Streamflow Depletion Caused by Groundwater Pumping: Fundamental Research Priorities for Management-relevant Science. Water Resources Research, 60, e2023WR035727.


51. Yuan, Y.*, L. Wang, Z. Wei, H. Ajami, H. Wang, T. Du. 2024. Using Median Point in Keeling Plot to Reduce the Uncertainty of the Isotopic Composition of Evapotranspiration. Journal of Hydrometeorology

50. Duro, A. M.*, D.R. Hirmas, H. Ajami, S.A. Billings, X. Zhang, L. Li, A. Flores, V. Moreno, X. Cao, J. Guilinger, E. Oleghe, D. Giménez, A. Gray, P.L. Sullivan. 2024. Topographic Correction of Visible Near-Infrared Reflectance Spectra for Horizon-Scale Soil Organic Carbon Mapping. Soil Science Society of America Journal, 00, 00–00.

49. Chen, L.*, J. Šimůnek, S.A. Bradford, H. Ajami, M.B. Meles. 2023. Coupling Water, Solute, and Sediment Transport into a New Computationally Efficient Hydrologic Model. Journal of Hydrology


48. Lee, S.*, H. Ajami.2023. Comprehensive Assessment of Baseflow Responses to Long-term Meteorological Droughts across the United States. Journal of Hydrology

  • Rivers may not recover from drought for years (UCR press release) 

  • River recovery from drought can take years (AGU Eos)

  • River recoveries can take years due to prolonged drought, lack of rain, study shows (Nature World News)

47. Koop, A.N., D.R. Hirmas, S.A. Billings, L. Li, A. Cueva, X. Zhang, H. Wen, A. Nemes, L.F.T. Souza, H. Ajami, A.N. Flores, A.K. Rudick, A. Guthrie, L.M. Klamm, M. Unruh, P.L. Sullivan.2023. Is Macroporosity Controlled by Complexed Clay and Soil Organic Carbon? Geoderma 437, 116565.

46. Brookfield, A.E., S. Zipper, A.D. Kendall, H. Ajami, J.M. Deines. 2023. Estimating Groundwater Pumping for Irrigation - A Method Comparison. Groundwater.

45. Souza, L.F.T., D.R. Hirmas, P.L. Sullivan, D.C. Reuman, M.F. Kirk, L. Li, H. Ajami, H. Wen, M.V.M. Sarto, T.D. Loecke, A.K. Rudick, C.W. Rice, S.A. Billings. 2023. Root Distributions, Precipitation, and Soil Structure Converge to Govern Soil Organic Carbon Depth Distributions. Geoderma. 437, 116569.

44. Brookfield, A.E., H. Ajami, R.W.H. Carroll, C. Tague, P.L. Sullivan, L.E. Condon.2023. Recent advances in integrated hydrologic models: Integration of new domains. Journal of Hydrology. 620, 129515.

43. Aiken, M.L., C.E. Pace, M. Ramachandran, K.A. Schwabe, H. Ajami, B.G. Link, S.C. Ying. 2023. Disparities in Drinking Water Manganese Concentrations in Domestic Wells and Community Water Systems in the Central Valley, CA, USA. Environmental Science and Technology. 57, 1987–1996.


42. Chen, L.*, J. Šimůnek, S.A. Bradford, H. Ajami, M.B. Meles. 2022. A Computationally Efficient Hydrologic Modeling Framework to Simulate Surface-Subsurface Hydrological Processes at the Hillslope Scale. Journal of Hydrology

41. Stephens, C. M., L.A. Marshall, F.M. Johnson, H. Ajami, L. Lin, L.E.  Band. 2022. Spatial Variation in Catchment Response to Climate Change Depends on Lateral Moisture Transport and Nutrient Dynamics. Water Resources Research, 58, e2021WR030577.

40. Acero Triana, J. S.*, H. Ajami. 2022. Identifying Major Hydrologic Change Drivers in a Highly Managed Transboundary Endorheic Basin: Integrating Hydro-ecological Models and Time-Series Data Mining Techniques. Water Resources Research, 58, e2022WR032281.

39. Wen, H., P.L. Sullivan, S.A. Billings, H. Ajami, A. Cueva, A. Flores, D.R. Hirmas, A.N. Koop, K. Murenbeeld, X. Zhang, L. Li.2022. From Soils to Streams: Connecting Terrestrial Carbon Transformation, Chemical Weathering, and Solute Export Across Hydrological Regimes. Water Resources Research, 58, e2022WR032314.

38. Schreiner-McGraw, A. P.*, H. Ajami, R.GAnderson, D. Wang. 2022. Integrating Partitioned Evapotranspiration Data into Hydrologic Models: Vegetation Parameterization and Uncertainty Quantification of Simulated Plant Water Use. Hydrological Processes, 36(6), e14580.

37. Bradly, T., H. Ajami, W. Porter. 2022. Ecological Transitions at the Salton Sea: Past, Present and Future, California Agriculture,

36. Zipper, S.C., W.H. Farmer, A. Brookfield, H. Ajami, H.W. Reeves, C. Wardropper, J.C. Hammond, T. Gleeson, J.M. Deines. 2022. Quantifying Streamflow Depletion from Groundwater Pumping: A Practical Review of Past and Emerging Approaches for Water Management, Journal of the American Water Resources Association


35. Schreiner-McGraw, A*, H. Ajami.2022. Combined Impacts of Uncertainty in Precipitation and Air Temperature on Simulated Mountain System Recharge from an Integrated Hydrologic Model, Hydrology & Earth System Sciences

34. Sullivan, P.L., S. Billings, D. Hirmas, L. Li, X. Zhang, S. Ziegler, K. Murenbeeld, H. Ajami, A. Guthrie, K. Singha, D. Giménez, A. Duro, V. Moreno, A. Flores, A. Cueva,  Koop, E.L. Aronson, H.R. Barnard, S.A. Banwart, R.M. Keen, A. Nemes, N.P. Nikolaidis, J.B. Nippert, D. Richter, D.A. Robinson, K. Sadayappan, L.F.T. de Souza, M. Unruh, H. Wen. 2022. Embracing the Dynamic Nature of Soil Structure: A Paradigm Illuminating the Role of Life in Critical Zones of the Anthropocene, Earth-Science Reviews,

33. Cowger, W.C., A. Gray, H. Hapich, J. Osei-Enin, B. Huynh, H. Nogi, S. Singh, S. Brownlee, J. Fong, T. Lok, G. Singer, H. Ajami.2022. Litter Origins, Accumulation Rates, and Hierarchical Composition on Urban Roadsides of the Inland Empire, California, Environmental Research Letters 


32. Schreiner-McGraw, A.*, H. Ajami.2021. Delayed Response of Groundwater to Multi-year Meteorological Droughts in the Absence of Anthropogenic Management, Journal of Hydrology


31. Schreiner-McGraw, A.*, H. Ajami.2020. Impact of Uncertainty in Precipitation Forcing Datasets on the Hydrologic Budget of an Integrated Hydrologic Model in Mountainous Terrain, Water Resources Research

30. Kim, S., H. Ajami, A. Sharma. 2020. Using Remotely Sensed Information to Improve Vegetation Parameterization in a Semi-distributed Hydrological Model (SMART) for Upland Catchments in Australia, Remote Sensing

29. Stephens, C. M., L.A. Marshall, F.M. Johnson, L. Lin, L.E. Band, and H. Ajami. 2020. Is Past Variability a Suitable Proxy for Future Change? A Virtual Catchment Experiment, Water Resources Research, 56,

28. Schreiner-McGraw*, A., E.R. Vivoni, H. Ajami, O.E. Sala, H.L. Throop, D.P.C. Peters.2020. Woody Plant Encroachment has a Larger Impact than Climate Change on Dryland Water Budgets, Scientific Reports,



27. Schreiner-McGraw*, A., H. Ajami, E. Vivoni.2019. Extreme Weather Events and Transmission Losses in Arid Streams, Environmental Research Letters, doi: 10.1088/1748-9326/ab2949

26. Tang, Y., L. Marshall, A. Sharma, H. Ajami, D.J. Nott. 2019. Ecohydrologic Error Models for Improved Bayesian Inference in Remotely Sensed Catchments, Water Resources Research

25. Fan, Y., M. Clark, D. M. Lawrence, S. Swenson, L. E. Band, S. L. Brantley, P. D. Brooks, W. E. Dietrich, A. Flores, G. Grant, J. W. Kirchner, D. S. Mackay, J. J. McDonnell, P. C. D. Milly, P. L. Sullivan, C. Tague, H. Ajami, N. Chaney, A. Hartmann, P. Hazenberg, J. McNamara, J. Pelletier, J. Perket, E. Rouholahnejad-Freund, T. Wagener, X. Zeng, E. Beighley, J. Buzan, M Huang, B. Livneh, B. P. Mohanty, B. Nijssen, M. Safeeq, C. Shen, W. van Verseveld, J. Volk, D Yamazaki. 2019. Hillslope Hydrology in Global Change Research and Earth System Modeling, Water Resources Research


24. Tang, Y., L. Marshall, A. Sharma, H. Ajami. 2018. Modelling Precipitation Uncertainties in a Multi-objective Bayesian Ecohydrological Setting, Advances in Water Resources

23. Ajami, H., A. Sharma. 2018. Disaggregating Soil Moisture to Finer Spatial Resolutions - A Comparison of Alternatives, Water Resources Research,

22. Sandoval, E., G. Baldo, N., Núñez, J., Oyarzún, J.P. Fairley, H. Ajami, J.L. Arumí, E. Aguirre, H. Maturana, R. Oyarzún. 2018. Groundwater Recharge Assessment in a Rural, Arid, Mid-mountain Basin in North-Central Chile, Hydrological Sciences Journal, 63(13-14),1873-1889,

21. Khan, U., H. Ajami, N.K. Tuteja, A. Sharma, S. Kim. 2018. Catchment Scale Simulations of Soil Moisture Dynamics Using an Equivalent Cross-Section based Hydrological Modelling Approach, Journal of Hydrology.

20. Tang, Y., L. Marshall, A. Sharma, H. Ajami. 2018. A Bayesian Alternative for Multi-objective Ecohydrological Model Specification, Journal of Hydrology


19. Niraula, R., T. Meixner, F. Dominguez, N. Bhattarai, M. Rodell, H. Ajami, D. Gochis, C. Castro. 2017. How Might Recharge Change Under Projected Climate Change in the Western US?, Geophysical Research Letters, doi:10.1002/2017GL075421

18. Niraula, R., T, Meixner, H. Ajami, M. Rodell, D. Gochis, C.L. Castro. 2017. Comparing Potential Recharge Estimates from Three Land Surface Models across the Western US​, Journal of Hydrology

17. Gemitzi, A., H. Ajami, H. Richnow. 2017. Developing Empirical Monthly Groundwater Recharge Equations based on Modeling and Remote Sensing Data - Modeling Future Groundwater Recharge to Predict Potential Climate Change Impacts​, Journal of Hydrology

16. Ajami, H., A. Sharma, L.E. Band, J.P. Evans, N. K. Tuteja, G.E. Amirthanathan, M.A. Bari. 2017. On the Non-stationarity of Hydrological Response in Anthropogenically Unaffected Catchments: An Australian Perspective, Hydrology and Earth System Sciencesdoi:10.5194/hess-21-281-2017


15. Ajami, H., U. Khan, N.K. Tuteja, A. Sharma. 2016. Development of a Computationally Efficient Semi-distributed Hydrologic Modeling Application for Soil Moisture, Lateral Flow and Runoff Simulation, Environmental Modelling & Software. doi: 10.1016/j.envsoft.2016.09.002

14. Meixner, T., A. Manning, D. Stonestrom, D.M. Allen, H. Ajami, K. Blasch, A. Brookfield, C.L. Castro,  J.F. Clark, D. Gochis, A. Flint, K. Neff, R. Niraula, M. Rodell, B. Scanlon, K. Singha, M. Walvoord. 2016. Implications of Prospective Climate Change for Groundwater Recharge in the Western United States, Journal of Hydrology, doi:10.1016/j.jhydrol.2015.12.027

13. Naseem, B., H. Ajami, Y. Liu, I. Cordery, A. Sharma. 2016. Multi-objective Assessment of Three Remote Sensing Vegetation Products for Streamflow Prediction in a Conceptual Ecohydrological Model, Journal of Hydrology, doi:10.1016/j.jhydrol.2016.10.038


12. Ajami, H., M.F. McCabe, J.P. Evans. 2015. Impacts of Model Initialization on an Integrated Surface Water–Groundwater Model, Hydrological Processes, 29(17):3790-3801, doi: 10.1002/hyp.10478

11. Naseem, B., H. Ajami, I. Cordery, A. Sharma. 2015. A Multi-objective Assessment of Alternate Conceptual Ecohydrological Models, Journal of Hydrology, 529(3):1221-1234, doi:10.1016/j.jhydrol.2015.08.060

10. Graham, P., M. Andersen, M.F. McCabe, H. Ajami, A. Baker, I. Acworth. 2015. To What Extent Do Long-Duration High-Volume Dam Releases Influence River-Aquifer Interactions? A Case Study in New South Wales, Australia, Hydrogeology Journal, 23: 319-334, doi: 10.1007/s10040-014-1212-3


9. Ajami, H., J.P. Evans, M.F. McCabe, S. Stisen. 2014. Technical Note: Reducing the Spin-up Time of Integrated Surface Water–Groundwater Models, Hydrology and Earth System Sciences, 18, 5169-5179, doi: 10.5194/hess-18-5169-2014

8. Ajami, H., M.F. McCabe, J.P. Evans, S. Stisen. 2014. Assessing the Impact of Model Spin-up on Surface Water-Groundwater Interactions Using an Integrated Hydrologic Model, Water Resources Research, 50: doi:10.1002/2013WR014258

7. Khan, U., N. Tuteja, H. Ajami, A. Sharma. 2014. An Equivalent Cross-Sectional Basis for Semi-Distributed Hydrological Modeling, Water Resources Research, 50, doi:10.1002/2013WR014741


6. Ajami, H., T. Maddock III, T. Meixner, J.F. Hogan, D.P. Guertin.2012. RIPGIS-NET: A GIS Tool for Riparian Groundwater Evapotranspiration in MODFLOW, Ground Water, 50(1): 154-158, doi:10.1111/j.1745-6584.2011.00809.x

5. Abramowitz, G., L. Pouyanne, H. Ajami. 2012. On the Information Content of Surface Meteorology for Downward Atmospheric Long-wave Radiation Synthesis, Geophysical Research Letters, 39: doi:10.1029/2011GL050726

4. Ajami, H., T. Meixner, F. Dominguez, J.F. Hogan, T. Maddock III. 2012. Seasonalizing Mountain System Recharge in Semi-Arid Basins-Climate Change Impacts, Ground Water, 50(4): 585-597, doi:10.1111/j.1745-6584.2011.00881.x

Prior to 2011

3. Ajami, H., P.A. Troch, T. Maddock III, T. Meixner, C. Eastoe. 2011. Quantifying Mountain Block Recharge by Means of Catchment-Scale Storage-Discharge Relationship, Water Resources Research, 47, W04504, doi:10.1029/2010WR009598

2. Ajami, H., T. Meixner, T. Maddock III, J.F. Hogan, D.P. Guertin.2011. Impact of Land-Surface Elevation and Riparian Evapotranspiration Seasonality on Groundwater Budget in MODFLOW Models, Hydrogeology Journal, 19:1181-1188, doi:10.1007/s10040-011-0743-0

1. Stromberg, J.C., M.G.F. Tluczek, A.F. Hazelton, H. Ajami.2010. A Century of Riparian Forest Expansion Following Extreme Disturbance: Spatio-Temporal Change in Populus/Salix/Tamarix Forests Along the Upper San Pedro River, Arizona, USA, Forest Ecology and Management, 259 (6):1181-1189, doi:10.1016/j.foreco.2010.01.005

Book Chapters

1. Ajami, H. 2021. Geohydrology: Global Hydrological Cycle, In: Alderton, David; Elias, Scott A. (eds.) Encyclopedia of Geology, 2nd edition, vol.[6], pp. 393-398. United Kingdom: Academic Press,

2. Ajami, H.2021. Geohydrology: Groundwater, In: Alderton, David; Elias, Scott A. (eds.) Encyclopedia of Geology, 2nd edition, vol.[6], pp. 408-415. United Kingdom: Academic Press,


bottom of page