Dr Ulysse Pasquier is a researcher in flood risk management and climate adaptation. Ulysse obtained his PhD in Environmental Science from the University of East Anglia in 2020 under the supervision of Dr Helen He. In partnership with the Broads Authority, this NERC-funded CASE studentship looked to assess future compound flooding risks in the Broadland Catchment. Ulysse has since carried out research on urban resilience at the Lawrence Berkeley National Laboratory in California, US. His work focused on developing process-based approaches to model the impact of land use and climatic changes on water resources and flooding risk in cities such as Los Angeles. Ulysse (re)joined the Tyndall Centre in 2023 as a senior research associate as part of the EU-funded CoCliCo project, which is developing coastal climate services for Europe related to marine flooding and sea-level rise. Within CoCliCo, Ulysse is initially assessing and synthesising contemporary coastal flood adaptation practise across European coastal nations to create a baseline for European-scale analysis over the coming century.
Ulysse Pasquier
2024
Gudde, Ross; He, Yi; Pasquier, Ulysse; Forstenhäusler, Nicole; Noble, Ciar; Zha, Qianyu
Quantifying future changes of flood hazards within the Broadland catchment in the UK Journal Article
In: Natural Hazards, 2024, ISSN: 0921-030X.
@article{f7db0252b99a4609ad66e956b7113ce9,
title = {Quantifying future changes of flood hazards within the Broadland catchment in the UK},
author = {Ross Gudde and Yi He and Ulysse Pasquier and Nicole Forstenhäusler and Ciar Noble and Qianyu Zha},
doi = {10.1007/s11069-024-06590-5},
issn = {0921-030X},
year = {2024},
date = {2024-04-21},
journal = {Natural Hazards},
publisher = {Springer},
abstract = {Flooding represents the greatest natural threat to the UK, presenting severe risk to populations along coastlines and floodplains through extreme tidal surge and hydrometeorological events. Climate change is projected to significantly elevate flood risk through increased severity and frequency of occurrences, which will be exacerbated by external drivers of risk such as property development and population growth throughout floodplains. This investigation explores the entire flood hazard modelling chain, utilising the nonparametric bias correction of UKCP18 regional climate projections, the distributed HBV-TYN hydrological model and HEC-RAS hydraulic model to assess future manifestation of flood hazard within the Broadland Catchment, UK. When assessing the independent impact of extreme river discharge and storm surge events as well as the impact of a compound event of the two along a high emission scenario, exponential increases in hazard extent over time were observed. The flood extent increases from 197 km2 in 1990 to 200 km2 in 2030, and 208 km2 in 2070. In parallel, exponential population exposure increases were found from 13,917 (1990) to 14,088 (2030) to 18,785 (2070). This methodology could see integration into policy-based flood risk management by use of the developed hazard modelling tool for future planning and suitability of existing infrastructure at a catchment scale.},
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2023
Rhoades, Alan M.; Zarzycki, Colin M.; Inda-Diaz, Héctor A.; Ombadi, Mohammed; Pasquier, Ulysse; Srivastava, Abhishekh; Hatchett, Benjamin J.; Dennis, Eli; Heggli, Anne; McCrary, Rachel; McGinnis, Seth; Rahimi-Esfarjani, Stefan; Slinskey, Emily; Ullrich, Paul A.; Wehner, Michael; Jones, Andrew D.
Recreating the California New Year’s flood event of 1997 in a regionally refined earth system model Journal Article
In: Journal of Advances in Modeling Earth Systems, vol. 15, no. 10, 2023, ISSN: 1942-2466, (Funding Information: This study was primarily funded by the Director, Office of Science, Office of Biological and Environmental Research of the U.S. Department of Energy Regional and Global Model Analysis (RGMA) Program. Authors Inda-Diaz, Ombadi, Pasquier, Rhoades, Srivastava, Ullrich, and Wehner were funded by “the Calibrated and Systematic Characterization, Attribution and Detection of Extremes (CASCADE)” Science Focus Area (award no. DE-AC02-05CH11231). Authors Dennis, Jones, McCrary, McGinnis, Rahimi-Esfarjani, Rhoades, Slinskey, Srivastava, Ullrich, and Zarzycki were funded by the “An Integrated Evaluation of the Simulated Hydroclimate System of the Continental US” project (award no. DE-SC0016605). Authors Hatchett and Heggli received support from the Nevada Department of Transportation under agreement P296-22-803. We would also like to acknowledge Smitha Buddhavarapu and Kripa Jagannathan for the considerable time and energy they provided in facilitating scientist-stakeholder discussions in the HyperFACETS project. The facilitated discussions played a key role in helping us to choose the 1997 flood event as a featured storyline within the HyperFACETS project. We also appreciate their constructive suggestions on our manuscript draft. We also thank the two anonymous reviewers and editor for their constructive comments and revision requests that elevated the impact and enhanced the clarity of our manuscript. Funding Information: This study was primarily funded by the Director, Office of Science, Office of Biological and Environmental Research of the U.S. Department of Energy Regional and Global Model Analysis (RGMA) Program. Authors Inda‐Diaz, Ombadi, Pasquier, Rhoades, Srivastava, Ullrich, and Wehner were funded by “the Calibrated and Systematic Characterization, Attribution and Detection of Extremes (CASCADE)” Science Focus Area (award no. DE‐AC02‐05CH11231). Authors Dennis, Jones, McCrary, McGinnis, Rahimi‐Esfarjani, Rhoades, Slinskey, Srivastava, Ullrich, and Zarzycki were funded by the “An Integrated Evaluation of the Simulated Hydroclimate System of the Continental US” project (award no. DE‐SC0016605). Authors Hatchett and Heggli received support from the Nevada Department of Transportation under agreement P296‐22‐803. We would also like to acknowledge Smitha Buddhavarapu and Kripa Jagannathan for the considerable time and energy they provided in facilitating scientist‐stakeholder discussions in the HyperFACETS project. The facilitated discussions played a key role in helping us to choose the 1997 flood event as a featured storyline within the HyperFACETS project. We also appreciate their constructive suggestions on our manuscript draft. We also thank the two anonymous reviewers and editor for their constructive comments and revision requests that elevated the impact and enhanced the clarity of our manuscript. Publisher Copyright: © 2023 The Authors. Journal of Advances in Modeling Earth Systems published by Wiley Periodicals LLC on behalf of American Geophysical Union.).
@article{e74d9cbf289d439ebd8fc843251c6882,
title = {Recreating the California New Year's flood event of 1997 in a regionally refined earth system model},
author = {Alan M. Rhoades and Colin M. Zarzycki and Héctor A. Inda-Diaz and Mohammed Ombadi and Ulysse Pasquier and Abhishekh Srivastava and Benjamin J. Hatchett and Eli Dennis and Anne Heggli and Rachel McCrary and Seth McGinnis and Stefan Rahimi-Esfarjani and Emily Slinskey and Paul A. Ullrich and Michael Wehner and Andrew D. Jones},
doi = {10.1029/2023MS003793},
issn = {1942-2466},
year = {2023},
date = {2023-10-01},
journal = {Journal of Advances in Modeling Earth Systems},
volume = {15},
number = {10},
publisher = {American Geophysical Union},
abstract = {The 1997 New Year's flood event was the most costly in California's history. This compound extreme event was driven by a category 5 atmospheric river that led to widespread snowmelt. Extreme precipitation, snowmelt, and saturated soils produced heavy runoff causing widespread inundation in the Sacramento Valley. This study recreates the 1997 flood using the Regionally Refined Mesh capabilities of the Energy Exascale Earth System Model (RRM-E3SM) under prescribed ocean conditions. Understanding the processes causing extreme events informs practical efforts to anticipate and prepare for such events in the future, and also provides a rich context to evaluate model skill in representing extremes. Three California-focused RRM grids, with horizontal resolution refinement of 14 km down to 3.5 km, and six forecast lead times, 28 December 1996 at 00Z through 30 December 1996 at 12Z, are assessed for their ability to recreate the 1997 flood. Planetary to synoptic scale atmospheric circulations and integrated vapor transport are weakly influenced by horizontal resolution refinement over California. Topography and mesoscale circulations, such as the Sierra barrier jet, are better represented at finer horizontal resolutions resulting in better estimates of storm total precipitation and storm duration snowpack changes. Traditional time-series and causal analysis frameworks are used to examine runoff sensitivities state-wide and above major reservoirs. These frameworks show that horizontal resolution plays a more prominent role in shaping reservoir inflows, namely the magnitude and time-series shape, than forecast lead time, 2-to-4 days prior to the 1997 flood onset.},
note = {Funding Information: This study was primarily funded by the Director, Office of Science, Office of Biological and Environmental Research of the U.S. Department of Energy Regional and Global Model Analysis (RGMA) Program. Authors Inda-Diaz, Ombadi, Pasquier, Rhoades, Srivastava, Ullrich, and Wehner were funded by “the Calibrated and Systematic Characterization, Attribution and Detection of Extremes (CASCADE)” Science Focus Area (award no. DE-AC02-05CH11231). Authors Dennis, Jones, McCrary, McGinnis, Rahimi-Esfarjani, Rhoades, Slinskey, Srivastava, Ullrich, and Zarzycki were funded by the “An Integrated Evaluation of the Simulated Hydroclimate System of the Continental US” project (award no. DE-SC0016605). Authors Hatchett and Heggli received support from the Nevada Department of Transportation under agreement P296-22-803. We would also like to acknowledge Smitha Buddhavarapu and Kripa Jagannathan for the considerable time and energy they provided in facilitating scientist-stakeholder discussions in the HyperFACETS project. The facilitated discussions played a key role in helping us to choose the 1997 flood event as a featured storyline within the HyperFACETS project. We also appreciate their constructive suggestions on our manuscript draft. We also thank the two anonymous reviewers and editor for their constructive comments and revision requests that elevated the impact and enhanced the clarity of our manuscript. Funding Information: This study was primarily funded by the Director, Office of Science, Office of Biological and Environmental Research of the U.S. Department of Energy Regional and Global Model Analysis (RGMA) Program. Authors Inda‐Diaz, Ombadi, Pasquier, Rhoades, Srivastava, Ullrich, and Wehner were funded by “the Calibrated and Systematic Characterization, Attribution and Detection of Extremes (CASCADE)” Science Focus Area (award no. DE‐AC02‐05CH11231). Authors Dennis, Jones, McCrary, McGinnis, Rahimi‐Esfarjani, Rhoades, Slinskey, Srivastava, Ullrich, and Zarzycki were funded by the “An Integrated Evaluation of the Simulated Hydroclimate System of the Continental US” project (award no. DE‐SC0016605). Authors Hatchett and Heggli received support from the Nevada Department of Transportation under agreement P296‐22‐803. We would also like to acknowledge Smitha Buddhavarapu and Kripa Jagannathan for the considerable time and energy they provided in facilitating scientist‐stakeholder discussions in the HyperFACETS project. The facilitated discussions played a key role in helping us to choose the 1997 flood event as a featured storyline within the HyperFACETS project. We also appreciate their constructive suggestions on our manuscript draft. We also thank the two anonymous reviewers and editor for their constructive comments and revision requests that elevated the impact and enhanced the clarity of our manuscript. Publisher Copyright: © 2023 The Authors. Journal of Advances in Modeling Earth Systems published by Wiley Periodicals LLC on behalf of American Geophysical Union.},
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}
2022
Pasquier, Ulysse; Vahmani, Pouya; Jones, Andrew D.
Quantifying the city-scale impacts of impervious surfaces on groundwater recharge potential: An urban application of WRF–Hydro Journal Article
In: Water, vol. 14, no. 19, 2022, ISSN: 2073-4441, (Acknowledgements: This research was funded by the Laboratory Directed Research and Development Program of Lawrence Berkeley National Laboratory under U.S. Department of Energy Contract No. DE–AC02–05CH11231 and by the Regional and Global Climate Modeling Program (RGCM) program under “the Calibrated and Systematic Characterization, Attribution and Detection of Extremes (CASCADE)” Science Focus Area (award no. DE-AC02-05CH11231). Analysis and model simulations were performed using the National Energy Research Scientific Computing Center (NERSC), specifically Cori-KNL supercomputing facilities (contract number DE-AC02-05CH11231).).
@article{92a1587a105e4114a209ef4c552310af,
title = {Quantifying the city-scale impacts of impervious surfaces on groundwater recharge potential: An urban application of WRF–Hydro},
author = {Ulysse Pasquier and Pouya Vahmani and Andrew D. Jones},
doi = {10.3390/w14193143},
issn = {2073-4441},
year = {2022},
date = {2022-10-06},
urldate = {2022-11-13},
journal = {Water},
volume = {14},
number = {19},
publisher = {MDPI AG},
abstract = {Decades of urbanization have created sprawling, complex, and vulnerable cities, half of which are located in water-scarce areas. With the looming effects of climate change, including increasing droughts and water shortages, there is an urgent need to better understand how urbanization impacts the water cycle at city scale. Impervious surfaces disrupt the natural flow of water, affecting groundwater recharge in water-scarce cities, such as Los Angeles, looking to harness local water resources. In the face of growing water demand, informing on opportunities to maximize potential groundwater recharge can help increase cities’ resilience. WRF–Hydro, a physics-based hydrological modeling system, capable of resolving atmospheric, land surface, and hydrological processes at city scale, is adapted to represent urban impervious surfaces. The modified model is used to assess the hydrological implications of historical urbanization. Pre- and post-urban scenarios are used to quantify the impacts of impervious surfaces on the local water budget. Our results show that urbanization in LA has vastly decreased the potential for groundwater recharge, with up to half of the water inflow being redirected from infiltration in highly urbanized watersheds, while doubling surface runoff’s share of the city’s water budget, from ~15% to 30%. This study not only sheds light on the role of imperviousness on groundwater recharge in water-scarce cities, but also offers a robust and transferable tool for the management of urban land and water resources.},
note = {Acknowledgements: This research was funded by the Laboratory Directed Research and Development Program of Lawrence Berkeley National Laboratory under U.S. Department of Energy Contract No. DE–AC02–05CH11231 and by the Regional and Global Climate Modeling Program (RGCM) program under “the Calibrated and Systematic Characterization, Attribution and Detection of Extremes (CASCADE)” Science Focus Area (award no. DE-AC02-05CH11231). Analysis and model simulations were performed using the National Energy Research Scientific Computing Center (NERSC), specifically Cori-KNL supercomputing facilities (contract number DE-AC02-05CH11231).},
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2020
Pasquier, Ulysse; Few, Roger; Goulden, Marisa C.; Hooton, Simon; He, Yi; Hiscock, Kevin M.
In: Environmental Science & Policy, vol. 103, pp. 50–57, 2020, ISSN: 1462-9011.
@article{b3e2cd9e27be44d798a9607ed817b569,
title = {“We can’t do it on our own!”—Integrating stakeholder and scientific knowledge of future flood risk to inform climate change adaptation planning in a coastal region},
author = {Ulysse Pasquier and Roger Few and Marisa C. Goulden and Simon Hooton and Yi He and Kevin M. Hiscock},
doi = {10.1016/j.envsci.2019.10.016},
issn = {1462-9011},
year = {2020},
date = {2020-01-01},
journal = {Environmental Science & Policy},
volume = {103},
pages = {50–57},
publisher = {Elsevier},
abstract = {Decision-makers face a particular challenge in planning for climate adaptation. The complexity of climate change's likely impacts, such as increased flooding, has widened the scope of information necessary to take action. This is particularly the case in valuable low-lying coastal regions, which host many competing interests, and where there is a growing need to draw from varied fields in the risk-based management of flooding. The rising scrutiny over science's ability to match expectations of policy actors has called for the integration of stakeholder and scientific knowledge domains. Focusing on the Broads — the United Kingdom's largest protected wetland — this study looked to assess future flood risk and consider potential adaptation responses in a collaborative approach. Interviews and surveys with local stakeholders accompanied the development of a hydraulic model in an iterative participatory design, centred on a scientist-stakeholder workshop. Knowledge and perspectives were shared on processes driving risk in the Broads, as well as on the implications of adaptation measures, allowing for their prioritisation. The research outcomes highlight not only the challenges that scientist-stakeholder integrated assessments of future flood risk face, but also their potential to lead to the production of useful information for decision-making.},
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2019
Pasquier, Ulysse; He, Yi; Hooton, Simon; Goulden, Marisa; Hiscock, Kevin M.
An integrated 1D–2D hydraulic modelling approach to assess the sensitivity of a coastal region to compound flooding hazard under climate change Journal Article
In: Natural Hazards, vol. 98, no. 3, pp. 915–937, 2019, ISSN: 0921-030X.
@article{379572305f10420cbc4d5633b36238ef,
title = {An integrated 1D–2D hydraulic modelling approach to assess the sensitivity of a coastal region to compound flooding hazard under climate change},
author = {Ulysse Pasquier and Yi He and Simon Hooton and Marisa Goulden and Kevin M. Hiscock},
doi = {10.1007/s11069-018-3462-1},
issn = {0921-030X},
year = {2019},
date = {2019-09-01},
journal = {Natural Hazards},
volume = {98},
number = {3},
pages = {915–937},
publisher = {Springer},
abstract = {Coastal regions are dynamic areas that often lie at the junction of different natural hazards. Extreme events such as storm surges and high precipitation are significant sources of concern for flood management. As climatic changes and sea-level rise put further pressure on these vulnerable systems, there is a need for a better understanding of the implications of compounding hazards. Recent computational advances in hydraulic modelling offer new opportunities to support decision-making and adaptation. Our research makes use of recently released features in the HEC-RAS version 5.0 software to develop an integrated 1D–2D hydrodynamic model. Using extreme value analysis with the Peaks-Over-Threshold method to define extreme scenarios, the model was applied to the eastern coast of the UK. The sensitivity of the protected wetland known as the Broads to a combination of fluvial, tidal and coastal sources of flooding was assessed, accounting for different rates of twenty-first century sea-level rise up to the year 2100. The 1D–2D approach led to a more detailed representation of inundation in coastal urban areas, while allowing for interactions with more fluvially dominated inland areas to be captured. While flooding was primarily driven by increased sea levels, combined events exacerbated flooded area by 5–40% and average depth by 10–32%, affecting different locations depending on the scenario. The results emphasise the importance of catchment-scale strategies that account for potentially interacting sources of flooding.},
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