The tree rings in this whitebark pine (Pinus albicaulis) cross-section provide a view back in time. Scientists study the patterns of tree ring growth, scars, and wood coloration to determine how long the tree lived, record changes in climate, and even track past fires, insect attacks, and earthquakes!
Greg Pederson, Ph.D.
Greg Pederson is a research scientist working primarily on the role of climate variability in driving changes in water resources, and other biological and physical components of mountainous ecosystems in western North America.
Research Interests
Of particular interest is the magnitude of low-frequency hydroclimatic variability and its implications for drought risk, as well as the climatic drivers associated with observed changes in mountain snowpack, streamflow, glaciers, and forest disturbance events. Understanding the time intervals and spatial scales over which these processes operate requires a long-term perspective, and for that I rely on proxy records primarily from tree-ring and lake sediments along with instrumental and modeled climate records. Recent and ongoing studies have addressed the susceptibility of natural resources to climate variability and change, and sought to apply both the modern and paleoclimatic records to present day resource management problems.
Current Research Projects Include:
- Drivers of Drought in the Upper Colorado River Basin [DOI Southwestern CSC]
- Multi-century perspectives on current and future streamflow in the Missouri River Basin [NSF P2C2]
- Reconstructions of Columbia River flow from winter and summer precipitation sensitive proxies in the Northwestern U.S. with implications for 21st century flow [CSC and CLU]
- A Broader view of North American climate over the past two millennia: Synthesizing paleoclimate records from diverse archives [USGS Powell Center]
- Holocene climate variability in Alaska from relict wood [DOI Alaska CSC]
- Holocene climates of the Northern Rockies from relict wood emerging from ice patches [CLU]
- Megadroughts and uncertainty in Upper Colorado River flow low-frequency variability [CLU]
Education and Certifications
Ph.D. Watershed Management & Ecohydrology. 2010. University of Arizona, School of Natural Resources.
M.S. Environmental Science. 2004. Montana State University
B.S. Ecology and Evolution in Botany & Zoology. 2000. Michigan State University
Affiliations and Memberships*
Greg is affiliate faculty with the Earth Sciences department and the Institute on Ecosystems (IoE) at Montana State University.
Science and Products
Building drought early warning systems for fisheries and water management across the U.S.
Reconstructing Ancient Human and Ecosystem Responses to Holocene Climate Conditions
Multi-century perspectives on current and future streamflow in the Missouri River Basin
Characterizing Historic Streamflow to Support Drought Planning in the Upper Missouri River Basin
Anticipating Future Impacts of Temperature on Streamflow in the Colorado River Basin
Drivers of Drought in the Upper Colorado River Basin
Mid-Holocene-to-present Modeled (ca., 7,000 to 100 cal. BP) and Reconstructed (ca., 5,900 to 5,436 cal. BP) Temperature for the High-Elevations of the Greater Yellowstone Ecosystem: Derived from a Transient Climate Model and Whitebark Pine Tree-rings Mid-Holocene-to-present Modeled (ca., 7,000 to 100 cal. BP) and Reconstructed (ca., 5,900 to 5,436 cal. BP) Temperature for the High-Elevations of the Greater Yellowstone Ecosystem: Derived from a Transient Climate Model and Whitebark Pine Tree-rings
Radiocarbon dating of silicified wood from around Artemisia Geyser in the Upper Geyser Basin, Yellowstone National Park Radiocarbon dating of silicified wood from around Artemisia Geyser in the Upper Geyser Basin, Yellowstone National Park
Radiocarbon dating of silicified wood from around Steamboat Geyser in Norris Geyser Basin, Yellowstone National Park, 2021-2022 Radiocarbon dating of silicified wood from around Steamboat Geyser in Norris Geyser Basin, Yellowstone National Park, 2021-2022
Cool Season (September-June) Total Precipitation Reconstruction for Deschutes County, Oregon, 1000-1991 CE Cool Season (September-June) Total Precipitation Reconstruction for Deschutes County, Oregon, 1000-1991 CE
A network of eight naturalized streamflow reconstructions for the Milk and St Mary Rivers spanning years 1017 - 1998 CE A network of eight naturalized streamflow reconstructions for the Milk and St Mary Rivers spanning years 1017 - 1998 CE
Tree ring dataset for a regional avalanche chronology in northwest Montana, 1636-2017 Tree ring dataset for a regional avalanche chronology in northwest Montana, 1636-2017
The tree rings in this whitebark pine (Pinus albicaulis) cross-section provide a view back in time. Scientists study the patterns of tree ring growth, scars, and wood coloration to determine how long the tree lived, record changes in climate, and even track past fires, insect attacks, and earthquakes!
Dynamic treeline and cryosphere response to pronounced mid-Holocene climatic variability in the US Rocky Mountains Dynamic treeline and cryosphere response to pronounced mid-Holocene climatic variability in the US Rocky Mountains
Drought as an emergent driver of ecological transformation in the twenty-first century Drought as an emergent driver of ecological transformation in the twenty-first century
Organic layers preserved in ice patches: A new record of Holocene environmental change on the Beartooth Plateau, USA Organic layers preserved in ice patches: A new record of Holocene environmental change on the Beartooth Plateau, USA
Big avalanches in a changing climate: Using tree-ring derived avalanche chronologies to examine avalanche frequency across multiple climate types Big avalanches in a changing climate: Using tree-ring derived avalanche chronologies to examine avalanche frequency across multiple climate types
Using tree rings to compare Colorado’s 2019 avalanche cycle to previous large avalanche cycles Using tree rings to compare Colorado’s 2019 avalanche cycle to previous large avalanche cycles
The relation between decadal droughts and eruptions of Steamboat Geyser in Yellowstone National Park, USA The relation between decadal droughts and eruptions of Steamboat Geyser in Yellowstone National Park, USA
Science and Products
Building drought early warning systems for fisheries and water management across the U.S.
Reconstructing Ancient Human and Ecosystem Responses to Holocene Climate Conditions
Multi-century perspectives on current and future streamflow in the Missouri River Basin
Characterizing Historic Streamflow to Support Drought Planning in the Upper Missouri River Basin
Anticipating Future Impacts of Temperature on Streamflow in the Colorado River Basin
Drivers of Drought in the Upper Colorado River Basin
Mid-Holocene-to-present Modeled (ca., 7,000 to 100 cal. BP) and Reconstructed (ca., 5,900 to 5,436 cal. BP) Temperature for the High-Elevations of the Greater Yellowstone Ecosystem: Derived from a Transient Climate Model and Whitebark Pine Tree-rings Mid-Holocene-to-present Modeled (ca., 7,000 to 100 cal. BP) and Reconstructed (ca., 5,900 to 5,436 cal. BP) Temperature for the High-Elevations of the Greater Yellowstone Ecosystem: Derived from a Transient Climate Model and Whitebark Pine Tree-rings
Radiocarbon dating of silicified wood from around Artemisia Geyser in the Upper Geyser Basin, Yellowstone National Park Radiocarbon dating of silicified wood from around Artemisia Geyser in the Upper Geyser Basin, Yellowstone National Park
Radiocarbon dating of silicified wood from around Steamboat Geyser in Norris Geyser Basin, Yellowstone National Park, 2021-2022 Radiocarbon dating of silicified wood from around Steamboat Geyser in Norris Geyser Basin, Yellowstone National Park, 2021-2022
Cool Season (September-June) Total Precipitation Reconstruction for Deschutes County, Oregon, 1000-1991 CE Cool Season (September-June) Total Precipitation Reconstruction for Deschutes County, Oregon, 1000-1991 CE
A network of eight naturalized streamflow reconstructions for the Milk and St Mary Rivers spanning years 1017 - 1998 CE A network of eight naturalized streamflow reconstructions for the Milk and St Mary Rivers spanning years 1017 - 1998 CE
Tree ring dataset for a regional avalanche chronology in northwest Montana, 1636-2017 Tree ring dataset for a regional avalanche chronology in northwest Montana, 1636-2017
The tree rings in this whitebark pine (Pinus albicaulis) cross-section provide a view back in time. Scientists study the patterns of tree ring growth, scars, and wood coloration to determine how long the tree lived, record changes in climate, and even track past fires, insect attacks, and earthquakes!
The tree rings in this whitebark pine (Pinus albicaulis) cross-section provide a view back in time. Scientists study the patterns of tree ring growth, scars, and wood coloration to determine how long the tree lived, record changes in climate, and even track past fires, insect attacks, and earthquakes!
Dynamic treeline and cryosphere response to pronounced mid-Holocene climatic variability in the US Rocky Mountains Dynamic treeline and cryosphere response to pronounced mid-Holocene climatic variability in the US Rocky Mountains
Drought as an emergent driver of ecological transformation in the twenty-first century Drought as an emergent driver of ecological transformation in the twenty-first century
Organic layers preserved in ice patches: A new record of Holocene environmental change on the Beartooth Plateau, USA Organic layers preserved in ice patches: A new record of Holocene environmental change on the Beartooth Plateau, USA
Big avalanches in a changing climate: Using tree-ring derived avalanche chronologies to examine avalanche frequency across multiple climate types Big avalanches in a changing climate: Using tree-ring derived avalanche chronologies to examine avalanche frequency across multiple climate types
Using tree rings to compare Colorado’s 2019 avalanche cycle to previous large avalanche cycles Using tree rings to compare Colorado’s 2019 avalanche cycle to previous large avalanche cycles
The relation between decadal droughts and eruptions of Steamboat Geyser in Yellowstone National Park, USA The relation between decadal droughts and eruptions of Steamboat Geyser in Yellowstone National Park, USA
*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