The objectives of this project are to reconstruct detailed histories of Holocene hydroclimate and corresponding environmental change from geological archives such as lake sediment, peat, and wood to more fully understand past, ongoing, and future change and its impacts.
Study sites for this research are located in the intermountain regions of western North America, including Alaska. The overarching research goal is to develop a spatial network of hydroclimatic records for the past ~10,000 years (The Holocene) that have the ability to detect climate change on decade-to-century time scales. These data are used to investigate past large-scale atmosphere-ocean dynamics that are known to currently influence western U.S. water availability. Several proxy methods are utilized with primary emphasis on isotope geochemistry of lake sediments, fossil moss and wood. Results lead to better understanding of the full range of potential climate states during the most recent period in earth's history with similar global boundary conditions as the pre-industrial period.
Why is this research important?
Documenting past climate, landscapes and ecosystems provides the necessary long-term context to better understand the changes in earth systems taking place today. This project provides a comparable long-term perspective of water availability. Examples of questions addressed by this project are:
- What is the Holocene range of Rocky Mountain precipitation variability and how has it varied seasonally in space and time?
- What is the Holocene range of temperature and precipitation variability in Alaska and how do past variations relate to Rocky Mountain patterns?
- What is the Holocene range of North American Monsoon dynamics and how have they influenced the seasonal balance of precipitation and drought in the west?
Below are publications associated with this project.
High sensitivity of gross primary production in the Rocky Mountains to summer rain
Water isotope systematics: Improving our palaeoclimate interpretations
Isotopes in North American Rocky Mountain snowpack 1993–2014
A multi-proxy record of hydroclimate, vegetation, fire, and post-settlement impacts for a subalpine plateau, Central Rocky Mountains U.S.A
An 8700 year paleoclimate reconstruction from the southern Maya lowlands
Controls on recent Alaskan lake changes identified from water isotopes and remote sensing
Rocky Mountain hydroclimate: Holocene variability and the role of insolation, ENSO, and the North American Monsoon
Enhanced Late Holocene ENSO/PDO expression along the margins of the eastern North Pacific
Holocene record of precipitation seasonality from lake calcite δ18O in the central Rocky Mountains, United States
Lake carbonate-δ18 records from the Yukon Territory, Canada: Little Ice Age moisture variability and patterns
- Overview
The objectives of this project are to reconstruct detailed histories of Holocene hydroclimate and corresponding environmental change from geological archives such as lake sediment, peat, and wood to more fully understand past, ongoing, and future change and its impacts.
Project scientists and collaborators obtain lake sediment cores from the lake ice in Alaska in early spring. Geochemical climate proxies obtained from lake sediments document climate change and impacts over the past ~10,000 years and provide a long-term context to more fully understand past, ongoing and future change. (Credit: Lesleigh Anderson, USGS GECSC. Public domain.) Study sites for this research are located in the intermountain regions of western North America, including Alaska. The overarching research goal is to develop a spatial network of hydroclimatic records for the past ~10,000 years (The Holocene) that have the ability to detect climate change on decade-to-century time scales. These data are used to investigate past large-scale atmosphere-ocean dynamics that are known to currently influence western U.S. water availability. Several proxy methods are utilized with primary emphasis on isotope geochemistry of lake sediments, fossil moss and wood. Results lead to better understanding of the full range of potential climate states during the most recent period in earth's history with similar global boundary conditions as the pre-industrial period.
Why is this research important?
Documenting past climate, landscapes and ecosystems provides the necessary long-term context to better understand the changes in earth systems taking place today. This project provides a comparable long-term perspective of water availability. Examples of questions addressed by this project are:
- What is the Holocene range of Rocky Mountain precipitation variability and how has it varied seasonally in space and time?
- What is the Holocene range of temperature and precipitation variability in Alaska and how do past variations relate to Rocky Mountain patterns?
- What is the Holocene range of North American Monsoon dynamics and how have they influenced the seasonal balance of precipitation and drought in the west?
- Publications
Below are publications associated with this project.
High sensitivity of gross primary production in the Rocky Mountains to summer rain
In the catchments of the Rocky Mountains, peak snowpack is declining in response to warmer spring temperatures. To understand how this will influence terrestrial gross primary production (GPP), we compared precipitation data across the intermountain west with satellite retrievals of solar-induced fluorescence (SIF), a proxy for GPP. Annual precipitation patterns explained most of the spatial and tWater isotope systematics: Improving our palaeoclimate interpretations
The stable isotopes of oxygen and hydrogen, measured in a variety of archives, are widely used proxies in Quaternary Science. Understanding the processes that control δ18O change have long been a focus of research (e.g. Shackleton and Opdyke, 1973; Talbot, 1990 ; Leng, 2006). Both the dynamics of water isotope cycling and the appropriate interpretation of geological water-isotope proxy time seriesIsotopes in North American Rocky Mountain snowpack 1993–2014
We present ∼1300 new isotopic measurements (δ18O and δ2H) from a network of snowpack sites in the Rocky Mountains that have been sampled since 1993. The network includes 177 locations where depth-integrated snow samples are collected each spring near peak accumulation. At 57 of these locations snowpack samples were obtained for 10–21 years and their isotopic measurements provide unprecedented spatA multi-proxy record of hydroclimate, vegetation, fire, and post-settlement impacts for a subalpine plateau, Central Rocky Mountains U.S.A
Apparent changes in vegetation distribution, fire, and other disturbance regimes throughout western North America have prompted investigations of the relative importance of human activities and climate change as potential causal mechanisms. Assessing the effects of Euro-American settlement is difficult because climate changes occur on multi-decadal to centennial time scales and require longer timeAn 8700 year paleoclimate reconstruction from the southern Maya lowlands
Analysis of a sediment core from Lago Puerto Arturo, a closed basin lake in northern Peten, Guatemala, has provided an ∼8700 cal year record of climate change and human activity in the southern Maya lowlands. Stable isotope, magnetic susceptibility, and pollen analyses were used to reconstruct environmental change in the region. Results indicate a relatively wet early to middle Holocene followed bByEnergy and Minerals Mission Area, Climate Research and Development Program, Energy Resources Program, Groundwater and Streamflow Information Program, Mineral Resources Program, National Laboratories Program, Science and Decisions Center, Geology, Minerals, Energy, and Geophysics Science Center, Geosciences and Environmental Change Science CenterControls on recent Alaskan lake changes identified from water isotopes and remote sensing
High-latitude lakes are important for terrestrial carbon dynamics and waterfowl habitat driving a need to better understand controls on lake area changes. To identify the existence and cause of recent lake area changes in the Yukon Flats, a region of discontinuous permafrost in north central Alaska, we evaluate remotely sensed imagery with lake water isotope compositions and hydroclimatic parameteRocky Mountain hydroclimate: Holocene variability and the role of insolation, ENSO, and the North American Monsoon
Over the period of instrumental records, precipitation maximum in the headwaters of the Colorado Rocky Mountains has been dominated by winter snow, with a substantial degree of interannual variability linked to Pacific ocean–atmosphere dynamics. High-elevation snowpack is an important water storage that is carefully observed in order to meet increasing water demands in the greater semi-arid regionEnhanced Late Holocene ENSO/PDO expression along the margins of the eastern North Pacific
Pacific climate is known to have varied during the Holocene, but spatial patterns remain poorly defined. This paper compiles terrestrial and marine proxy data from sites along the northeastern Pacific margins and proposes that they indicate 1) suppressed ENSO conditions during the middle Holocene between ∼8000 and 4000 cal BP with a North Pacific that generally resembled a La Niña-like or more negHolocene record of precipitation seasonality from lake calcite δ18O in the central Rocky Mountains, United States
A context for recent hydroclimatic extremes and variability is provided by a ∼10 k.y. sediment carbonate oxygen isotope (δ18O) record at 5–100 yr resolution from Bison Lake, 3255 m above sea level, in northwestern Colorado (United States). Winter precipitation is the primary water source for the alpine headwater lake in the Upper Colorado River Basin and lake water δ18O measurements reflect seasonLake carbonate-δ18 records from the Yukon Territory, Canada: Little Ice Age moisture variability and patterns
A 1000-yr history of climate change in the central Yukon Territory, Canada, is inferred from sediment composition and isotope geochemistry from small, groundwater fed, Seven Mile Lake. Recent observations of lake-water δ18O, lake level, river discharge, and climate variations, suggest that changes in regional effective moisture (precipitation minus evaporation) are reflected by the lake’s hydrolog