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Sarah N Rosa

Sarah Rosa is a hydrologist with the Pacific Islands Water Science Center in Honolulu, Hawaiʻi.

Sarah Rosa has been a hydrologist with the USGS Pacific Islands Water Science Center since 2008. She has conducted surface-water studies using watershed and water-balance models in Guam and Hawaiʻi that are part of water-availability investigations. Her continued surface-water studies include understanding climate-based changes to runoff and groundwater recharge.

 

Education

MS, Natural Resources and Environmental Management (Watershed Hydrology), University of Hawaiʻi at Mānoa, 2013 

BS, Environmental Earth Science, Dartmouth College, 2007

 

Professional Experience

Hydrologist, USGS Pacific Islands Water Science Center, 2008‒present

Research Internship, University of California, San Diego’s Summer Training Academy for Research in the Sciences at Scripps Institute of Oceanography, 2007

Laboratory/Field Assistant, Department of Oceanography, University of Hawaiʻi at Mānoa, 2006

Laboratory Assistant, Department of Earth Sciences, Dartmouth College, 2005

 

Science and Products

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Image: Haleakala National Park

Effects of Drought on Soil Moisture and Water Resources in Hawai‘i

Droughts in the Hawaiian Islands can enhance wildfire risk, diminish freshwater resources, and devastate threatened and endangered species on land and in nearshore ecosystems. During periods of drought, cloud-water interception, or fog drip (the process by which water droplets accumulate on the leaves and branches of plants and then drip to the ground) in Hawai‘i’s rain forests may play an importa
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Climate Adaptation Science Centers
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Effects of Drought on Soil Moisture and Water Resources in Hawai‘i

Droughts in the Hawaiian Islands can enhance wildfire risk, diminish freshwater resources, and devastate threatened and endangered species on land and in nearshore ecosystems. During periods of drought, cloud-water interception, or fog drip (the process by which water droplets accumulate on the leaves and branches of plants and then drip to the ground) in Hawai‘i’s rain forests may play an importa
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Seepage Runs of Hālawa Stream, Oʻahu, Hawaiʻi: December 2021 - June 2022

This data release contains four seepage runs conducted along selected reaches of South Hālawa Stream, North Hālawa Stream, and Hālawa Stream, Oʻahu, Hawaiʻi between December 2021 and June 2022. The data release has four child items that each consist of the following files: (1) a metadata xml file describing the child-item files and data attributes, (2) an annotated map showing the seepage-run meas
By
Pacific Islands Water Science Center

Seepage-run discharge measurements, March 23, 2022, He'eia Stream and 'Ioleka'a Stream, O'ahu, Hawai'i

This data release contains a comma-delimited ascii file of 15 discrete discharge measurements made at sites along selected reaches of He'eia Stream and 'Ioleka'a Stream, O'ahu, Hawai'i, on March 23, 2022. These discrete discharge measurements form what is commonly referred to as a "seepage run." The intent of the seepage run is to quantify the spatial distribution of streamflow along the reach dur
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Pacific Islands Water Science Center

Seepage-run discharge measurements, August 9, 2022, He'eia Stream and 'Ioleka'a Stream, O'ahu, Hawai'i

This data release contains a comma-delimited ascii file of 16 discrete discharge measurements made at sites along selected reaches of He'eia Stream and 'Ioleka'a Stream, O'ahu, Hawai'i, on August 9, 2022. These discrete discharge measurements form what is commonly referred to as a "seepage run." The intent of the seepage run is to quantify the spatial distribution of streamflow along the reach dur
By
Pacific Islands Water Science Center

Seepage-run discharge measurements, November 15, 2021, He'eia Stream and 'Ioleka'a Stream, O'ahu, Hawai'i

This data release contains a comma-delimited ascii file of 16 discrete discharge measurements made at sites along selected reaches of He'eia Stream and 'Ioleka'a Stream, O'ahu, Hawai'i, on November 15, 2021. These discrete discharge measurements form what is commonly referred to as a "seepage run." The intent of the seepage run is to quantify the spatial distribution of streamflow along the reach
By
Pacific Islands Water Science Center

Seepage-run discharge measurements, September 8, 2021, He'eia Stream and 'Ioleka'a Stream, O'ahu, Hawai'i

This data release contains a comma-delimited ascii file of nine discrete discharge measurements made at sites along selected reaches of He'eia Stream and 'Ioleka'a Stream, O'ahu, Hawai'i, on September 8, 2021. These discrete discharge measurements form what is commonly referred to as a "seepage run." The intent of the seepage run is to quantify the spatial distribution of streamflow along the reac
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Pacific Islands Water Science Center

Supporting data for Hanalei Watershed model: SWAT_Hanalei

This data release contains inputs and outputs needed to reproduce the Soil and Water Assessment Tool (SWAT) model findings for the publication: Fortini, L.B., Leopold, C.R., Perkins, K., Chadwick, O.A., Yelenik, S.G., Jacobi, J.D., Bishaw, K., II, Gregg, M. and Rosa, S., 2020, Local to landscape-level controls of water fluxes through Hawaiian forests: Effects of invasive animals and plants on soil
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Pacific Islands Water Science Center

Hawaiian Islands datasets quantifying the effects of invasive animals and plants on native forests across the archipelago 2019

Dataset includes publicly available geologic and rainfall data, and environmental and ecological data derived or collected for this project. Specifically, water infiltration measurements, interpreted field-saturated hydraulic conductivity values, ungulate activity, vegetation cover, general soil and weather conditions data are included. Soil samples were collected, lab analyzed, and are included i
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Pacific Island Ecosystems Research Center

Southern Guam watershed modeling and Fena Valley Reservoir water-balance model input files for historic (1990-2009) and future (2080-2099) climate conditions

This data release contains the input files for the watershed and water-balance models that simulate historic (1990-2009) and future (2080-2099) climate conditions on Guam. These simulations are described in the associated Scientific Investigations Report, "Water Resources on Guam-Potential Impacts of and Adaptive Response to Climate Change" by Stephen B. Gingerich, Adam G. Johnson, Sarah N. Rosa,
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Pacific Islands Water Science Center

Supporting data for Fena Valley Reservoir watershed and water-balance model, southern Guam

This data release contains inputs and outputs needed to reproduce the findings for the publication: Rosa, S.N., and Hay, L.E., in press, Fena Valley Reservoir watershed and water-balance model updates and expansion of watershed modeling to Southern Guam: U.S. Geological Survey Scientific Investigations Report 2017-5093, 64 p., https://doi.org/10.3133/sir20175093. Data are provided in several file
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Pacific Islands Water Science Center

Local to landscape-level controls of water fluxes through Hawaiian forests: Effects of invasive animals and plants on soil infiltration capacity across substrate and moisture gradients

Given the potential effect of invasive plants and animals to water fluxes through forests, the invasive-driven degradation of native ecosystems is a topic of great concern for many downstream land and water managers. The infiltration rate determines the partitioning between runoff and infiltration into soil in Hawaiian forests and beyond. Thus, to explore the ecohydrological effects of plant and a
Authors
Lucas B. Fortini, Christina Leopold, Kimberlie Perkins, Oliver A. Chadwick, Stephanie G. Yelenik, James D. Jacobi, Kaiena Bishaw, Makani Gregg, Sarah N. Rosa
By
Ecosystems Mission Area, Water Resources Mission Area, Pacific Island Ecosystems Research Center, Pacific Islands Water Science Center

Water resources on Guam—Potential impacts of and adaptive response to climate change

The goals of this joint U.S. Geological Survey, University of Hawaiʻi, University of Guam, University of Texas, and East-West Center study were to (1) provide basic understanding about water resources for U.S. Department of Defense installations on Guam and (2) assess the resulting effect of sea-level rise and a changing climate on freshwater availability, on the basis of historic information, sea
Authors
Stephen B. Gingerich, Adam G. Johnson, Sarah N. Rosa, Mathieu D. Marineau, Scott A. Wright, Lauren E. Hay, Matthew J. Widlansky, John W. Jenson, Corinne I. Wong, Jay L. Banner, Melissa L. Finucane, Victoria W. Keener
By
Water Resources Mission Area, Pacific Islands Water Science Center

Fena Valley Reservoir watershed and water-balance model updates and expansion of watershed modeling to southern Guam

In 2014, the U.S. Geological Survey, in cooperation with the U.S. Department of Defense’s Strategic Environmental Research and Development Program, initiated a project to evaluate the potential impacts of projected climate-change on Department of Defense installations that rely on Guam’s water resources. A major task of that project was to develop a watershed model of southern Guam and a water-bal
Authors
Sarah N. Rosa, Lauren E. Hay
By
Water Resources Mission Area, Pacific Islands Water Science Center

Measuring surface-water loss in Honouliuli Stream near the ‘Ewa Shaft, O‘ahu, Hawai‘i

The Honolulu Board of Water Supply is currently concerned with the possibility of bacteria in the pumped water of the ‘Ewa Shaft (State well 3-2202-21). Groundwater from the ‘Ewa Shaft could potentially be used to meet future potable water needs in the ‘Ewa area on the island of O‘ahu. The source of the bacteria in the pumped water is unknown, although previous studies indicate that surface water
Authors
Sarah N. Rosa
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Water Resources Mission Area, Pacific Islands Water Science Center

Hawaii StreamStats: A web application for defining drainage-basin characteristics and estimating peak-streamflow statistics

Reliable estimates of the magnitude and frequency of floods are necessary for the safe and efficient design of roads, bridges, water-conveyance structures, and flood-control projects and for the management of flood plains and flood-prone areas. StreamStats provides a simple, fast, and reproducible method to define drainage-basin characteristics and estimate the frequency and magnitude of peak disc
Authors
Sarah N. Rosa, Delwyn S. Oki
By
Water Resources Mission Area, Pacific Islands Water Science Center

Flood-frequency estimates for streams on Kauai, Oahu, Molokai, Maui, and Hawaii, State of Hawaii

This study provides an updated analysis of the magnitude and frequency of peak stream discharges in Hawai`i. Annual peak-discharge data collected by the U.S. Geological Survey during and before water year 2008 (ending September 30, 2008) at stream-gaging stations were analyzed. The existing generalized-skew value for the State of Hawai`i was retained, although three methods were used to evaluate w
Authors
Delwyn S. Oki, Sarah N. Rosa, Chiu W. Yeung
By
Water Resources Mission Area, Pacific Islands Water Science Center

A Multitracer Approach to Detecting Wastewater Plumes from Municipal Injection Wells in Nearshore Marine Waters at Kihei and Lahaina, Maui, Hawaii

Municipal wastewater plumes discharging from aquifer to ocean were detected by nearshore wading surveys at Kihei and Lahaina, on the island of Maui in Hawaii. Developed in cooperation with the Hawaii State Department of Health, the survey methodology included instrument trolling to detect submarine groundwater discharge, followed by analysis of water and macroalgae for a suite of chemical and isot
Authors
Charles D. Hunt, Sarah N. Rosa
By
Water Resources Mission Area, Pacific Islands Water Science Center
Adaptive management strategies for potential impacts of climate change on Guam

Adaptive management strategies for potential impacts of climate change on Guam

Guam’s water demands are anticipated to increase. Potential impacts of sea-level rise and a changing climate on surface-water and groundwater...

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