Hydrologic Change

Land cover and land use (LC/LU), climate, and biogeochemical processing are significant drivers of water quality in streams and rivers over broad scales of space and time. As LC/LU and climate continue to change we can expect changes in water quality. This project seeks to understand the drivers of spatial and temporal variability in water quality across scales using new and existing data to...

Climate-related forest disturbances, particularly drought-induced tree mortality and large, high-severity fires from increasingly warm and dry conditions, are altering forest ecosystems and the ecosystem services society depends on (e.g., water supplies). Our research combines long-term place-based ecological data, diverse methods (e.g., paleo, remote-sensing), and networking approaches to...

Changes in snowpack accumulation, distribution, and melt in high-elevation catchments are likely to have important impacts on water, carbon, and nitrogen cycles, which are tightly coupled through exchanges of energy and biogeochemical compounds between atmospheric, terrestrial, and aquatic environments. Our research helps to better understand how changes in climate will affect water availability...

Significant change to the Arctic and sub-arctic water cycle is underway, impacting hydrologic and biogeochemical fluxes. In southcentral Alaska, glacier mass loss, changes to precipitation (including the rain/snow fraction), thawing ground ice, and vegetation encroachment will change both magnitude and timing of water and solute fluxes downstream. Although altered fluxes of limiting nutrients are...

Forests provide society with economically important and often irreplaceable goods and services, such as wood products, carbon sequestration, clean water, biodiversity, and recreational opportunities. Yet hotter droughts (droughts in which unusually high temperatures exacerbate the effects of low precipitation) are projected to increase in frequency and intensity in coming decades, potentially...

Sea level and Storm Hazards: Past and Present is a multidisciplinary study of past changes in sea level. Prehistoric shorelines can be used as a baseline for current and future sea level changes under warmer-than-present climate. Emphasis is placed on looking at sea levels during warm periods of the last 500,000 years as well as how base level changes increase the risk of coastal inundation during...

Changes in rainfall patterns as a result of anthropogenic climate change are already having large ecological and socioeconomic impacts across the globe. Increases in flood damage, wildfire damage, and agricultural losses can all be attributed to anomalous rainfall events and prolonged droughts across the United States in recent years. Additionally, Atlantic Ocean circulation, which has a large...

Interactions between forested and urban landscapes can lead to reciprocal effects that have substantial impacts on water supply and ecology. Air pollution from urban and forested landscapes can be deposited on adjacent forests, while forest disturbance, such as wildfires and floods, can remobilize those contaminants. Additionally, pollutants from legacy land use (e.g., mining) can also be...

The Prairie Pothole Region (PPR) of North America is one of the most important breeding areas for continental waterfowl populations, a Department of Interior (DOI) trust resource. Land use and climate both influence the functioning of the region’s wetland ecosystems, with effects not just on the waterfowl that depend on these wetlands, but also on the services they provide to society, such as...

Extreme low streamflows impact water availability for human systems and ecosystems. Numerous researchers have analyzed trends in low streamflows in the U.S. There is no known published work, however, on historical trends over time in the most extreme low streamflows—the flows with the largest impacts on human systems and ecosystems. The current study attempts to fill this gap. The wealth of...

This project investigates the links between terrestrial and marine carbon cycling and fluvial transport of freshwater and dissolved organic carbon (DOC) to the near-coastal ocean. The project analyzes DOC export that integrates complex interacting processes in natural and human-impacted terrestrial and aquatic environments. Changes in DOC export may indicate changes in terrestrial ecosystem carbon...

Previous work performed as part of the USGS Holocene Synthesis project illuminated complex centennial-scale patterns of drought and wetter-than-average conditions across the North American continent interior during the past two millennia, where paleorecord data coverage is sparse. In order to explain the patterns of naturally-occurring drought, floods, and storms for the past, identified by the...