CUAHSI-AGU H3S Cyberseminar Series

Coastal Dynamics in a Changing World

Beaches as a dynamic reactor: spatiotemporal dynamics of coastal groundwater biogeochemistry (Kim)

Fresh groundwater in coastal aquifers experience biogeochemical reactions that alter nutrient fluxes to oceans. My research focuses on how these reactions vary over space and time, influenced by hydrology, reactant delivery, and carbon transport.

Nitrate Removal Capacity of Delta Wetlands (Knights)

Wetlands that establish on deltas have the potential to retain nutrients and act as a buffer that limits nutrient flux to oceans. This project aims to quantify nitrate removal capacity of deltas and to understand variability in removal rates among unique delta environments.

Numerical modeling of Tsunami-Induced seawater intrusion in coastal areas (Liu)

The Niijima Island, Japan is facing tsunami risks triggered by the anticipated Nankai Earthquake in the next 30 years. We simulated the seawater intrusion and aquifer recovery processes under this tsunami scenario using numerical modeling method.

Sea-level rise changes groundwater-surface water exchange and hydro-redox zonations in a temperate salt marsh: implications for carbon cycling (Guimond)

Using a hydrological model of a mid-Atlantic salt marsh, we simulate present-day and future sea-level scenarios to understand how coastal marsh groundwater-surface water exchange and hydro-redox zonations will change and assess the implications of these changes on coastal carbon dynamics.

Rivers and Lakes Under a Changing Climate

Climate impacts on Andean hydrology using a mountain systems approach (Somers)

As Andean glaciers recede, the capacity of snow and ice to buffer low flow periods is lost. We integrate climate, glacier, surface water and groundwater modelling techniques to project hydrologic change in an Andean catchment through 2100.

From the Elwha to the Mekong: Watershed-scale sediment dynamics under the impacts of hydropower dams and environmental change (Beveridge)

This talk will provide an overview of how interdisciplinary research approaches, encompassing computational modeling and satellite remote sensing, are being applied to understanding river network sediment transport and storage. These approaches are applied in two study areas of vastly different environmental conditions and stages of hydropower dam development: the Elwha River Basin of Washington State, where the world's largest dam removal recently occurred; and the Mekong River Basin of Southeast Asia, where hydropower development is rapidly advancing.

Water and water shortage in Iran, Case study Tashk-Bakhtegan and Maharlu lakes basin, Iran (Ghader)

In this study for the first time, complete research was carried out to understand the hydrologic circle of Tashk-Bakhtegan and Maharlu lakes' basin. In this study, those basins were evaluated in terms of meteorology, surface water, groundwater, water quality, and water balance was carried out. Although the agriculture section was evaluated as the most water consumer.

Climate change and mountain groundwater: an integrated field and numerical approach (Markovich)

Climate change will exacerbate water scarcity globally and particularly in snowmelt-dominated regions via a snow-to-rain shift and earlier snowmelt period. Observational records of mountain systems show evidence of this snow-to-rain transition; however, the mountain groundwater response is not well understood. This uncertainty is largely due to our inability to ‘see’ mountain groundwater, because mountain systems are generally data poor and deep wells completed in the mountain block are rarely available. My research blends field and numerical methods to characterize mountain groundwater systems with the ultimate goal of improved prediction of hydrologic response to climate change in mountain systems. First, I present a Bayesian hydrograph separation approach to better constrain the proportional contribution of groundwater to streamflow in a volcanic catchment in Central Chile. This approach is useful in data limited systems for developing a conceptual model of the surface water groundwater interactions, and for further hypothesis development of climate change response; however, this lacks a direct, quantitative link to integrated hydrologic models. My current research explores the use of multiple age tracers ( 3 H/ 3 He, 39 Ar, 14 C) in mountain groundwater systems as a direct link to an integrated hydrologic model, ParFlow-CLM, via particle tracking. This work aims to constrain estimates of mountain block recharge to the Tucson basin and project recharge response under future climate conditions.

Water Resources and Management

Hydrologic impacts and trade-offs associated with forest-based bioenergy development practices in a snow-dominated watershed, Wisconsin, USA (Heydari)

Tradeoffs between biomass production, hydrologic alteration, and fertilizer use are assessed. High density, short rotation treatments for poplar production produce the optimal tradeoff. Poplar ET exceeds original land ET in summer months, decreasing streamflows by up to 50%.

Patchy snowpacks can enhance groundwater recharge in a warmer climate (Beria)

Snowmelt is known to be more efficient in recharging groundwater than rain. As climate warms, more precipitation is expected in the form of rainfall vs snowfall, which can potentially decrease the amount of groundwater recharge. Somehow counterintuitively, we show that the opposite might be more likely using a combination of stable water isotopes and streamflow recession analysis for headwater catchments spread across Switzerland.

Emerging conflicts in water management due to trade-offs between human and environmental needs (Hassanzade)

This study aims at presenting the water management challenges to meet growing human water demand while maintaining environmental needs. Examples are given from the regional water resource system in the Province of Saskatchewan, Canada in terms of conflicts between developing upstream agriculture vs. downstream ecosystem livelihood in one of the North America’s largest inland deltas.

Whole Watershed Management to Maximize Total Water Storage (Goharian)

Growing water scarcity, due to natural and anthropogenic forces, in many parts of the world has a profound effect on human, agricultural, and environmental water needs. These concerns call for a stringent evaluation of future water resources sustainability and security. While the public and water resources planners habitually look to surface reservoirs for storage solutions, we show how total system water storage can be increased through reoperation of both the surface and subsurface reservoirs.

Water Pollution and Quality

Searching for freshwater in coastal Bangladesh (Peters)

Drinking water is hard to find in coastal Bangladesh. My research explores the (1) identification of potable groundwater, (2) factors influencing drinking water use, and (3) delivery of our findings to the local community.

Microplastics and poop, making number two, number one! (Rolsky)

Charlie Rolsky is a PhD candidate at Arizona State University investigating the effects of plastic pollution on marine ecosystems around the globe. He has developed new methods to better understand the transport, fate, and ultimate impact of microplastics on wild species, including whales.

Back to the Future: How Past Land Use Impacts Tomorrow’s Water Quality. (Van Meter)

In my work, I expand upon the idea of the river as spatial integrator and suggest that watersheds must also be seen as temporal integrators. Watersheds are not just the sums of their parts—they are the sums of their pasts and their presents. Accordingly, as changes in climate and land use lead us to a “new normal,” where past assumptions may no longer hold, we also remain strongly bound by the past.

Fundamental Water Issues associated with Algae biofuels (Tavakoli)

The goal of this chapter is to determine how an algal biofuel production facility would affect the water resources in a water-stressed region. This case study focuses on the Middle Rio Grande basin, which includes parts of Texas and New Mexico in the US and the State of Chihuahua in Mexico. Tasks to be done for this purpose start with land selection, developing an algae growth model, creating a water and salinity balance, define choices of water supply sources and allocations on water availability in the context of a changing climate and water use patterns, and managing datasets.