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John Crusius

John is a Research Chemist for the Alaska Science Center.

Science and Products

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Turquoise bay waters with forested island and snow-capped mountains in background

Webinar: Impacts of Climate Change and Melting Glaciers on Coastal Ecosystems in the Nearshore Waters of the Gulf of Alaska

View this webinar to learn more about the impacts metling glaciers have on Alaska's coastal wetlands.
By
Ecosystems, Climate Adaptation Science Centers, Climate Adaptation Science Centers
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Webinar: Impacts of Climate Change and Melting Glaciers on Coastal Ecosystems in the Nearshore Waters of the Gulf of Alaska

View this webinar to learn more about the impacts metling glaciers have on Alaska's coastal wetlands.
Learn More
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Image: Mountains over Copper River, AK

Impacts of Climate Change and Melting Glaciers on Coastal Ecosystems in the Gulf of Alaska

As glaciers melt from climate change, their contents – namely, large quantities of freshwater, sediment, and nutrients – are slowly released into coastal ecosystems. This project addressed the impacts of melting glaciers on coastal ecosystems in the Copper River region of the Gulf of Alaska, which is home to several commercially important fisheries. Researchers examined how glacial melting is alte...
By
Climate Adaptation Science Centers
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Impacts of Climate Change and Melting Glaciers on Coastal Ecosystems in the Gulf of Alaska

As glaciers melt from climate change, their contents – namely, large quantities of freshwater, sediment, and nutrients – are slowly released into coastal ecosystems. This project addressed the impacts of melting glaciers on coastal ecosystems in the Copper River region of the Gulf of Alaska, which is home to several commercially important fisheries. Researchers examined how glacial melting is alte...
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Gulf of Alaska Shelf and Slope Iron and Nitrate data, Copper River Region, 2010

These are data from cruises carried out in April, May and July 2010 from the Copper River (AK) mouth to beyond the shelf break, ~150 km from shore. The focus of the dataset is the iron (Fe) data, intended to help infer the processes controlling concentrations of Fe. The data include concentrations of total dissolvable Fe (TDFe), dissolved Fe (dFe), nitrate, and salinity, temperature and fluoresc
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Alaska Science Center

Coastal Groundwater Chemical Data from the North and South Shores of Long Island, New York

Groundwater data were collected in the spring and fall of 2008 from three sites representing different geological settings and biogeochemical conditions within the surficial glacial aquifer of Long Island, NY. Investigations were designed to examine the extent to which average vadose zone thickness in contributing watersheds controlled biogeochemical conditions and processes, including dissolved o
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Coastal and Marine Hazards and Resources Program, Woods Hole Coastal and Marine Science Center
Filter Total Items: 38

Dissolved Fe supply to the central Gulf of Alaska is inferred to be derived from Alaskan glacial dust that is not resolved by dust transport models

Re-examination of previously published dissolved iron time-series data from Ocean Station Papa in the central Gulf of Alaska (GoA) reveals 33-70% increases in the dissolved iron inventories occurring between September and February of successive years, implying a source of Fe to this region during autumn or early winter. Because I can virtually rule out many possible iron sources at this time of ye
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Alaska Science Center

Atmospheric deposition of glacial iron in the Gulf of Alaska impacted by the position of the Aleutian Low

Our understanding of glacial flour dust storm delivery of iron to the Gulf of Alaska (GoA) is limited. Here we interpret concurrent time series satellite, meteorological, and aerosol geochemical data from the GoA to examine how interannual variability in regional weather patterns impacts offshore aerosol glacial Fe deposition. In 2011, when a northerly Aleutian Low (AL) was persistent during fall,
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Groundwater and Streamflow Information Program, Alaska Science Center

Depth of the vadose zone controls aquifer biogeochemical conditions and extent of anthropogenic nitrogen removal

We investigated biogeochemical conditions and watershed features controlling the extent of nitrate removal through microbial dinitrogen (N2) production within the surficial glacial aquifer located on the north and south shores of Long Island, NY, USA. The extent of N2 production differs within portions of the aquifer, with greatest N2 production observed at the south shore of Long Island where the
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Woods Hole Coastal and Marine Science Center

Seasonal and spatial variabilities in northern Gulf of Alaska surface water iron concentrations driven by shelf sediment resuspension, glacial meltwater, a Yakutat eddy, and dust

Phytoplankton growth in the Gulf of Alaska (GoA) is limited by iron (Fe), yet Fe sources are poorly constrained. We examine the temporal and spatial distributions of Fe, and its sources in the GoA, based on data from three cruises carried out in 2010 from the Copper River (AK) mouth to beyond the shelf break. April data are the first to describe late winter Fe behavior before surface water nitrate
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Groundwater and Streamflow Information Program, Alaska Science Center

High-latitude dust in the Earth system

Natural dust is often associated with hot, subtropical deserts, but significant dust events have been reported from cold, high latitudes. This review synthesizes current understanding of high-latitude (≥50°N and ≥40°S) dust source geography and dynamics and provides a prospectus for future research on the topic. Although the fundamental processes controlling aeolian dust emissions in high latitude
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Groundwater and Streamflow Information Program, Alaska Science Center

Substantial nitrous oxide emissions from intertidal sediments and groundwater in anthropogenically-impacted West Falmouth Harbor, Massachusetts

Large N2O emissions were observed from intertidal sediments in a coastal estuary, West Falmouth Harbor, MA, USA. Average N2O emission rates from 41 chambers during summer 2008 were 10.7 mol N2O m(-2) h(-1)±4.43 μmol N2O m(-2) h(-1) (standard error). Emissions were highest from sediments within a known wastewater plume, where a maximum N2O emission rate was 155 μmol N2O m(-2) h(-1). Intertidal N2O
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Woods Hole Coastal and Marine Science Center

Centennial changes in North Pacific anoxia linked to tropical trade winds

Climate warming is expected to reduce oxygen (O2) supply to the ocean and expand its oxygen minimum zones (OMZs). We reconstructed variations in the extent of North Pacific anoxia since 1850 using a geochemical proxy for denitrification (δ15N) from multiple sediment cores. Increasing δ15N since ~1990 records an expansion of anoxia, consistent with observed O2 trends. However, this was preceded by
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Ecosystems, Alaska Science Center

Estuarine removal of glacial iron and implications for iron fluxes to the ocean

While recent work demonstrates that glacial meltwater provides a substantial and relatively labile flux of the micronutrient iron to oceans, the role of high-latitude estuary environments as a potential sink of glacial iron is unknown. Here we present the first quantitative description of iron removal in a meltwater-dominated estuary. We find that 85% of “dissolved” Fe is removed in the low-salini
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Groundwater and Streamflow Information Program, Alaska Science Center

Continuous resistivity profiling data from Great South Bay, Long Island, New York

An investigation of submarine aquifers adjacent to the Fire Island National Seashore and Long Island, New York was conducted to assess the importance of submarine groundwater discharge as a potential nonpoint source of nitrogen delivery to Great South Bay. Over 200 kilometers of continuous resistivity profiling data were collected to image the fresh-saline groundwater interface in sediments beneat
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Woods Hole Coastal and Marine Science Center

Continuous resistivity profiling data from Northport Harbor and Manhasset Bay, Long Island, New York

An investigation of coastal groundwater systems was performed along the North Shore of Long Island, New York, during May 2008 to constrain nutrient delivery to Northport Harbor and Manhasset Bay by delineating locations of likely groundwater discharge. The embayments are bounded by steep moraines and are underlain by thick, fine-grained sediments deposited in proglacial lakes during the last ice a
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Woods Hole Coastal and Marine Science Center

Continuous resistivity profiling data from the Corsica River Estuary, Maryland

Submarine groundwater discharge (SGD) into Maryland's Corsica River Estuary was investigated as part of a larger study to determine its importance in nutrient delivery to the Chesapeake Bay. The Corsica River Estuary represents a coastal lowland setting typical of much of the eastern bay. An interdisciplinary U.S. Geological Survey (USGS) science team conducted field operations in the lower estuar
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Woods Hole Coastal and Marine Science Center

Glacial influence on the geochemistry of riverine iron fluxes to the Gulf of Alaska and effects of deglaciation

Riverine iron (Fe) derived from glacial weathering is a critical micronutrient source to ecosystems of the Gulf of Alaska (GoA). Here we demonstrate that the source and chemical nature of riverine Fe input to the GoA could change dramatically due to the widespread watershed deglaciation that is underway. We examine Fe size partitioning, speciation, and isotopic composition in tributaries of the Co
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Woods Hole Coastal and Marine Science Center

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