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Joshua C Koch, Ph.D.

Surface water / groundwater interactions; hyporheic zone hydrology and biogeochemistry; carbon, nitrogen, and phosphorus cycling; flow above / through frozen ground; preferential flow and soil pipe formation and transport.

Professional Experience

  • 2011 - Present   Research Hydrologist, U.S. Geological Survey (USGS), Anchorage, AK

  • 2006 - 2011       Student Hydrologist, Branch of Regional Research, USGS, Boulder, CO

  • 2005 - 2006      Research Assistant, Institute of Alpine and Arctic Research, University of Colorado, Boulder

  • 2003 - 2005      Research Assistant, Semi-Arid Hydrology and Riparian Areas, University of Arizona, Tucson, AZ

  • 2002 - 2003      Hydrologist Intern, Branch of Regional Research, USGS, Lakewood, CO

  • 2001 - 2002      Hydrologist Intern, MA-RI Water District, USGS, Northborough, MA

Education and Certifications

  • PhD    2010    University of Colorado, Boulder, CO    Civil, Environmental, and Architectural Engineering

  • MS      2005   University of Arizona, Tucson, AZ        Department of Hydrology

  • BA      2001    Wesleyan University, Middletown, CT  Earth and Environmental Sciences

Affiliations and Memberships*

  • American Geophysical Union, Hydrology and Cryosphere Sections

  • American Water Resources Association - Alaska Chapter

  • Association of Polar Early Career Scientists

Science and Products

Filter Total Items: 58

Sensitivity of headwater streamflow to thawing permafrost and vegetation change in a warming Arctic Sensitivity of headwater streamflow to thawing permafrost and vegetation change in a warming Arctic

Climate change has the potential to impact headwater streams in the Arctic by thawing permafrost and subsequently altering hydrologic regimes and vegetation distribution, physiognomy and productivity. Permafrost thaw and increased subsurface flow have been inferred from the chemistry of large rivers, but there is limited empirical evidence of the impacts to headwater streams. Here we...
Authors
Joshua Koch, Ylva Sjoberg, Jonathan O’Donnell, Michael Carey, Pamela Sullivan, A. Terskaia
By
Alaska Science Center

Heterogeneous patterns of aged organic carbon export driven by hydrologic flow paths, soil texture, fire, and thaw in discontinuous permafrost headwaters Heterogeneous patterns of aged organic carbon export driven by hydrologic flow paths, soil texture, fire, and thaw in discontinuous permafrost headwaters

Climate change is thawing and potentially mobilizing vast quantities of organic carbon (OC) previously stored for millennia in permafrost soils of northern circumpolar landscapes. Climate-driven increases in fire and thermokarst may play a key role in OC mobilization by thawing permafrost and promoting transport of OC. Yet, the extent of OC mobilization and mechanisms controlling...
Authors
Joshua Koch, Matthew Bogard, David Butman, Kerri Finlay, Brian A. Ebel, Jason James, Sarah Johnston, Torre Jorgenson, Neal Pastick, Rob Spencer, Rob Striegl, Michelle Walvoord, Kimberly Wickland
By
Water Resources Mission Area, Earth Resources Observation and Science (EROS) Center , Alaska Science Center

Multi-year, spatially extensive, watershed-scale synoptic stream chemistry and water quality conditions for six permafrost-underlain Arctic watersheds Multi-year, spatially extensive, watershed-scale synoptic stream chemistry and water quality conditions for six permafrost-underlain Arctic watersheds

Repeated sampling of spatially distributed river chemistry can be used to assess the location, scale, and persistence of carbon and nutrient contributions to watershed exports. Here, we provide a comprehensive set of water chemistry measurements and ecohydrological metrics describing the biogeochemical conditions of permafrost-affected Arctic watersheds. These data were collected in...
Authors
Arial Shogren, Jay Zarnetske, Benjamin Abbott, Samuel Bratsman, Brian Brown, Michael Carey, Randy Fulweiber, Heather Greaves, Emma Haines, Frances Iannucci, Joshua Koch, Alex Medvedeff, Jonathan O’Donnell, Leika Patch, Brett Poulin, Tanner Williamson, William Bowden
By
Alaska Science Center

Seasonality of solute flux and water source chemistry in a coastal glacierized watershed undergoing rapid change: Wolverine Glacier watershed, Alaska Seasonality of solute flux and water source chemistry in a coastal glacierized watershed undergoing rapid change: Wolverine Glacier watershed, Alaska

As glaciers around the world rapidly lose mass, the tight coupling between glaciers and downstream ecosystems is resulting in widespread impacts on global hydrologic and biogeochemical cycling. However, a range of challenges make it difficult to conduct research in glacierized systems and our knowledge of seasonally changing hydrologic processes and solute sources and signatures is...
Authors
Anna Bergstrom, Joshua Koch, Shad O'Neel, Emily Baker
By
Ecosystems Land Change Science Program, Alaska Science Center

Storm-scale and seasonal dynamics of carbon export from a nested subarctic watershed underlain by permafrost Storm-scale and seasonal dynamics of carbon export from a nested subarctic watershed underlain by permafrost

Subarctic catchments underlain by permafrost sequester a major stock of frozen organic carbon (C), which may be mobilized as the Arctic warms. Warming can impact C export from thawing soils by altering the depth and timing of runoff related to changing storm and fire regimes and altered soil thaw depths. We investigated C export in a first order headwater stream (West Twin Creek) and its...
Authors
Joshua Koch, Mark Dornblaser, Rob Striegl
By
Ecosystems Mission Area, Alaska Science Center, Wildland Fire Science

Arctic insect emergence timing and composition differs across thaw ponds of varying morphology Arctic insect emergence timing and composition differs across thaw ponds of varying morphology

Freshwater ponds provide habitats for aquatic insects that emerge and subsidize consumers in terrestrial ecosystems. In the Arctic, insects provide an important seasonal source of energy to birds that breed and rear young on the tundra. The abundance and timing of insect emergence from arctic thaw ponds is poorly understood, but understanding these fluxes is important, given the role of...
Authors
Sarah Laske, Kirsty Gurney, Joshua Koch, Joel Schmutz, Mark Wipfli
By
Alaska Science Center
Filter Total Items: 17
Filter Total Items: 30

Water quality and gas fluxes of Interior Alaska (2014-2018) Water quality and gas fluxes of Interior Alaska (2014-2018)

This product consists of multiple tabular datasets and associated metadata of water quality information related to rivers, streams, and lakes in the Yukon River watershed between 2014 and 2018. This data release is apart of the National Aeronautics and Space Administration (NASA) funded Arctic-Boreal Vulnerability Experiment (ABoVE) and is an assessment of water quality and greenhouse...
By
Water Resources Mission Area

Descriptions, Depth to Refusal, and Field-Saturated Hydraulic Conductivity of Soils on the Arctic Coastal Plain of Alaska, 2012-2016 Descriptions, Depth to Refusal, and Field-Saturated Hydraulic Conductivity of Soils on the Arctic Coastal Plain of Alaska, 2012-2016

This dataset includes soil data collected from various landscapes adjacent to thaw ponds on the North Slope of Alaska between 2012 and 2018. The landscapes include ice-rich polygonal ground found on basin uplands, as well as bluffs and lake edges. At each site a visual description of soil type and texture was performed, and a permafrost probe was used to determine a 'depth to refusal'...
By
Alaska Science Center

Physical, Hydraulic, and Thermal Properties of Soils in the Noatak River Basin, Alaska, 2016 Physical, Hydraulic, and Thermal Properties of Soils in the Noatak River Basin, Alaska, 2016

This dataset includes physical, hydraulic, and thermal properties of soils collected in two sub-watersheds in the Noatak River Basin in northwestern Alaska. Physical properties include dry bulk density and porosity. Hydraulic properties include field- and lab-based hydraulic conductivity, soil-water retention data, and parameters used in a common soil-water retention model (van Genuchten...
By
Alaska Science Center

Water Level, Temperature, and Discharge of Headwater Streams in the Yukon River Basin, Alaska, 2016 and 2017 Water Level, Temperature, and Discharge of Headwater Streams in the Yukon River Basin, Alaska, 2016 and 2017

This dataset includes 15-minute interval data on stream temperature, stage, and discharge from low-order streams in the Yukon River Basin in interior Alaska, collected during the summer months. The depth of the water and temperature were determined using a combined pressure transducer and temperature sensor that was deployed through the summer months. Different sensors were used in each...
By
Alaska Science Center

Nitrogen biogeochemistry in a boreal headwater stream network in Interior Alaska, 2008 to 2011 Nitrogen biogeochemistry in a boreal headwater stream network in Interior Alaska, 2008 to 2011

High latitude, boreal watersheds are nitrogen-limited ecosystems that export large amounts of organic carbon. Key controls on carbon cycling in these environments are the biogeochemical processes affecting the nitrogen cycle. This data release presents results of a 3-year field study from 2008-2011 to document the relation between seasonal and transport-associated changes in carbon and...
By
Water Resources Mission Area

Water Level, Temperature, and Discharge of Headwater Streams in the Noatak and Kobuk River Basins, Northwest Alaska, 2015-2017 Water Level, Temperature, and Discharge of Headwater Streams in the Noatak and Kobuk River Basins, Northwest Alaska, 2015-2017

This dataset includes 15-minute interval data on stream temperature, stage, and discharge from low-order streams in the Noatak and Kobuk River valleys in Northwestern Alaska, collected during the summer months. Several sites in the Agashashok River basin were monitored in 2015 and 2016, and additional sites were added in 2017. The depth of the water and temperature were determined using...
By
Alaska Science Center
Filter Total Items: 65
A stream winding through polygonal ground on the Arctic Coastal Plain
A stream winding through polygonal ground on the Arctic Coastal Plain
A stream winding through polygonal ground on the Arctic Coastal Plain
A stream winding through polygonal ground on the Arctic Coastal Plain

A stream winding through polygonal ground on the Arctic Coastal Plain

A stream winding through polygonal ground on the Arctic Coastal Plain

A stream winding through polygonal ground on the Arctic Coastal Plain

By
Alaska Science Center
A stream winding through polygonal ground on the Arctic Coastal Plain

A stream winding through polygonal ground on the Arctic Coastal Plain

A stream winding through polygonal ground on the Arctic Coastal Plain

A stream winding through polygonal ground on the Arctic Coastal Plain

By
Alaska Science Center
Researchers collect water chemistry and invertebrates from a degrading trough pond
Collect water chemistry and invertebrates at a degrading trough pond
Collect water chemistry and invertebrates at a degrading trough pond
Researchers collect water chemistry and invertebrates from a degrading trough pond

Collect water chemistry and invertebrates at a degrading trough pond

Collect water chemistry and invertebrates at a degrading trough pond

Researchers collect water chemistry and invertebrates from a degrading trough pond.

By
Alaska Science Center
Researchers collect water chemistry and invertebrates from a degrading trough pond

Collect water chemistry and invertebrates at a degrading trough pond

Collect water chemistry and invertebrates at a degrading trough pond

Researchers collect water chemistry and invertebrates from a degrading trough pond.

By
Alaska Science Center

Science and Products

Filter Total Items: 58

Sensitivity of headwater streamflow to thawing permafrost and vegetation change in a warming Arctic Sensitivity of headwater streamflow to thawing permafrost and vegetation change in a warming Arctic

Climate change has the potential to impact headwater streams in the Arctic by thawing permafrost and subsequently altering hydrologic regimes and vegetation distribution, physiognomy and productivity. Permafrost thaw and increased subsurface flow have been inferred from the chemistry of large rivers, but there is limited empirical evidence of the impacts to headwater streams. Here we...
Authors
Joshua Koch, Ylva Sjoberg, Jonathan O’Donnell, Michael Carey, Pamela Sullivan, A. Terskaia
By
Alaska Science Center

Heterogeneous patterns of aged organic carbon export driven by hydrologic flow paths, soil texture, fire, and thaw in discontinuous permafrost headwaters Heterogeneous patterns of aged organic carbon export driven by hydrologic flow paths, soil texture, fire, and thaw in discontinuous permafrost headwaters

Climate change is thawing and potentially mobilizing vast quantities of organic carbon (OC) previously stored for millennia in permafrost soils of northern circumpolar landscapes. Climate-driven increases in fire and thermokarst may play a key role in OC mobilization by thawing permafrost and promoting transport of OC. Yet, the extent of OC mobilization and mechanisms controlling...
Authors
Joshua Koch, Matthew Bogard, David Butman, Kerri Finlay, Brian A. Ebel, Jason James, Sarah Johnston, Torre Jorgenson, Neal Pastick, Rob Spencer, Rob Striegl, Michelle Walvoord, Kimberly Wickland
By
Water Resources Mission Area, Earth Resources Observation and Science (EROS) Center , Alaska Science Center

Multi-year, spatially extensive, watershed-scale synoptic stream chemistry and water quality conditions for six permafrost-underlain Arctic watersheds Multi-year, spatially extensive, watershed-scale synoptic stream chemistry and water quality conditions for six permafrost-underlain Arctic watersheds

Repeated sampling of spatially distributed river chemistry can be used to assess the location, scale, and persistence of carbon and nutrient contributions to watershed exports. Here, we provide a comprehensive set of water chemistry measurements and ecohydrological metrics describing the biogeochemical conditions of permafrost-affected Arctic watersheds. These data were collected in...
Authors
Arial Shogren, Jay Zarnetske, Benjamin Abbott, Samuel Bratsman, Brian Brown, Michael Carey, Randy Fulweiber, Heather Greaves, Emma Haines, Frances Iannucci, Joshua Koch, Alex Medvedeff, Jonathan O’Donnell, Leika Patch, Brett Poulin, Tanner Williamson, William Bowden
By
Alaska Science Center

Seasonality of solute flux and water source chemistry in a coastal glacierized watershed undergoing rapid change: Wolverine Glacier watershed, Alaska Seasonality of solute flux and water source chemistry in a coastal glacierized watershed undergoing rapid change: Wolverine Glacier watershed, Alaska

As glaciers around the world rapidly lose mass, the tight coupling between glaciers and downstream ecosystems is resulting in widespread impacts on global hydrologic and biogeochemical cycling. However, a range of challenges make it difficult to conduct research in glacierized systems and our knowledge of seasonally changing hydrologic processes and solute sources and signatures is...
Authors
Anna Bergstrom, Joshua Koch, Shad O'Neel, Emily Baker
By
Ecosystems Land Change Science Program, Alaska Science Center

Storm-scale and seasonal dynamics of carbon export from a nested subarctic watershed underlain by permafrost Storm-scale and seasonal dynamics of carbon export from a nested subarctic watershed underlain by permafrost

Subarctic catchments underlain by permafrost sequester a major stock of frozen organic carbon (C), which may be mobilized as the Arctic warms. Warming can impact C export from thawing soils by altering the depth and timing of runoff related to changing storm and fire regimes and altered soil thaw depths. We investigated C export in a first order headwater stream (West Twin Creek) and its...
Authors
Joshua Koch, Mark Dornblaser, Rob Striegl
By
Ecosystems Mission Area, Alaska Science Center, Wildland Fire Science

Arctic insect emergence timing and composition differs across thaw ponds of varying morphology Arctic insect emergence timing and composition differs across thaw ponds of varying morphology

Freshwater ponds provide habitats for aquatic insects that emerge and subsidize consumers in terrestrial ecosystems. In the Arctic, insects provide an important seasonal source of energy to birds that breed and rear young on the tundra. The abundance and timing of insect emergence from arctic thaw ponds is poorly understood, but understanding these fluxes is important, given the role of...
Authors
Sarah Laske, Kirsty Gurney, Joshua Koch, Joel Schmutz, Mark Wipfli
By
Alaska Science Center
Filter Total Items: 17
Filter Total Items: 30

Water quality and gas fluxes of Interior Alaska (2014-2018) Water quality and gas fluxes of Interior Alaska (2014-2018)

This product consists of multiple tabular datasets and associated metadata of water quality information related to rivers, streams, and lakes in the Yukon River watershed between 2014 and 2018. This data release is apart of the National Aeronautics and Space Administration (NASA) funded Arctic-Boreal Vulnerability Experiment (ABoVE) and is an assessment of water quality and greenhouse...
By
Water Resources Mission Area

Descriptions, Depth to Refusal, and Field-Saturated Hydraulic Conductivity of Soils on the Arctic Coastal Plain of Alaska, 2012-2016 Descriptions, Depth to Refusal, and Field-Saturated Hydraulic Conductivity of Soils on the Arctic Coastal Plain of Alaska, 2012-2016

This dataset includes soil data collected from various landscapes adjacent to thaw ponds on the North Slope of Alaska between 2012 and 2018. The landscapes include ice-rich polygonal ground found on basin uplands, as well as bluffs and lake edges. At each site a visual description of soil type and texture was performed, and a permafrost probe was used to determine a 'depth to refusal'...
By
Alaska Science Center

Physical, Hydraulic, and Thermal Properties of Soils in the Noatak River Basin, Alaska, 2016 Physical, Hydraulic, and Thermal Properties of Soils in the Noatak River Basin, Alaska, 2016

This dataset includes physical, hydraulic, and thermal properties of soils collected in two sub-watersheds in the Noatak River Basin in northwestern Alaska. Physical properties include dry bulk density and porosity. Hydraulic properties include field- and lab-based hydraulic conductivity, soil-water retention data, and parameters used in a common soil-water retention model (van Genuchten...
By
Alaska Science Center

Water Level, Temperature, and Discharge of Headwater Streams in the Yukon River Basin, Alaska, 2016 and 2017 Water Level, Temperature, and Discharge of Headwater Streams in the Yukon River Basin, Alaska, 2016 and 2017

This dataset includes 15-minute interval data on stream temperature, stage, and discharge from low-order streams in the Yukon River Basin in interior Alaska, collected during the summer months. The depth of the water and temperature were determined using a combined pressure transducer and temperature sensor that was deployed through the summer months. Different sensors were used in each...
By
Alaska Science Center

Nitrogen biogeochemistry in a boreal headwater stream network in Interior Alaska, 2008 to 2011 Nitrogen biogeochemistry in a boreal headwater stream network in Interior Alaska, 2008 to 2011

High latitude, boreal watersheds are nitrogen-limited ecosystems that export large amounts of organic carbon. Key controls on carbon cycling in these environments are the biogeochemical processes affecting the nitrogen cycle. This data release presents results of a 3-year field study from 2008-2011 to document the relation between seasonal and transport-associated changes in carbon and...
By
Water Resources Mission Area

Water Level, Temperature, and Discharge of Headwater Streams in the Noatak and Kobuk River Basins, Northwest Alaska, 2015-2017 Water Level, Temperature, and Discharge of Headwater Streams in the Noatak and Kobuk River Basins, Northwest Alaska, 2015-2017

This dataset includes 15-minute interval data on stream temperature, stage, and discharge from low-order streams in the Noatak and Kobuk River valleys in Northwestern Alaska, collected during the summer months. Several sites in the Agashashok River basin were monitored in 2015 and 2016, and additional sites were added in 2017. The depth of the water and temperature were determined using...
By
Alaska Science Center
Filter Total Items: 65
A stream winding through polygonal ground on the Arctic Coastal Plain
A stream winding through polygonal ground on the Arctic Coastal Plain
A stream winding through polygonal ground on the Arctic Coastal Plain
A stream winding through polygonal ground on the Arctic Coastal Plain

A stream winding through polygonal ground on the Arctic Coastal Plain

A stream winding through polygonal ground on the Arctic Coastal Plain

A stream winding through polygonal ground on the Arctic Coastal Plain

By
Alaska Science Center
A stream winding through polygonal ground on the Arctic Coastal Plain

A stream winding through polygonal ground on the Arctic Coastal Plain

A stream winding through polygonal ground on the Arctic Coastal Plain

A stream winding through polygonal ground on the Arctic Coastal Plain

By
Alaska Science Center
Researchers collect water chemistry and invertebrates from a degrading trough pond
Collect water chemistry and invertebrates at a degrading trough pond
Collect water chemistry and invertebrates at a degrading trough pond
Researchers collect water chemistry and invertebrates from a degrading trough pond

Collect water chemistry and invertebrates at a degrading trough pond

Collect water chemistry and invertebrates at a degrading trough pond

Researchers collect water chemistry and invertebrates from a degrading trough pond.

By
Alaska Science Center
Researchers collect water chemistry and invertebrates from a degrading trough pond

Collect water chemistry and invertebrates at a degrading trough pond

Collect water chemistry and invertebrates at a degrading trough pond

Researchers collect water chemistry and invertebrates from a degrading trough pond.

By
Alaska Science Center

*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government

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