Paleoclimate and Paleoecology

The Atlantic Subsurface Stratigraphic Initiative (ASSI) is a project with an interdisciplinary group of scientists focused on documenting the Cretaceous and Cenozoic subsurface geology of the Salisbury Embayment across Maryland and Virginia. Data generated by ASSI is crucial for resolving stratigraphic issues across state boundaries and regions. By working closely with state geologic surveys, ASSI...

Estuaries and their surrounding wetlands are coastal transition zones where freshwater rivers meet tidal seawater. As sea levels rise, tidal forces move saltier water farther upstream, extending into freshwater wetland areas. Human changes to the surrounding landscape may amplify the effects of this tidal extension, impacting the resiliency and function of the upper estuarine wetlands. One visible...

The Greater Everglades Ecosystem, which includes Everglades National Park and Biscayne National Park, experienced significant alterations in the 20th century with the construction of canals to divert water, water management practices, growth of agriculture, and the rapidly expanding urban population of Miami and south Florida. In the 1990s a federal, state, and local effort to restore the Greater...

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...

Heavy rainfall, flooding, and drought frequently devastate North American populations and are predicted to continue posing serious threats over the next century. The nature of these phenomena at centennial and millennial timescales is not well constrained. Clarifying the spatial patterns of drought and moisture trends is fundamental for comparison with other datasets for the purposes of...

The Holocene Synthesis Project integrates a variety of information about past climate variability across the North American continent for the past ~12,000 years to characterize the spatial patterns of previous climate states, advance our understanding about mechanisms that drive natural climate variability, and improve the quality of climate models that are used to predict future climate patterns...

The Arctic is undergoing historically unprecedented changes in weather, sea ice, temperature and ecosystems. These changes have led to greater coastal erosion, greater export of freshwater, and changes to marine and terrestrial ecosystems, habitats, and productivity, among other trends. Meanwhile, many believe the Arctic “amplifies” large climate changes during both warm periods and ice ages and...

PRISM will help distinguish the USGS as a world leader in paleoclimate research, data generation and delivery for use in addressing the modern world's climate-related needs. We will be recognized for the passion of our researchers and partners in providing quality, innovative paleoclimate interpretation and data analysis to the science (climate change) community and to the public we serve.

The Greater Everglades Ecosystem covers much of south Florida, and the highest areas are only a few meters above sea level. Predictions of sea level rise and changes in storm intensity for the 21st century are particularly concerning to the urban population of Miami and the east coast, but also represent a challenge to Everglades National Park and Biscayne National Park resource managers. The...

Geological Investigations of the Neogene explores past warmer-than-modern climates of the mid-Miocene (about 14-17 million years ago) and Piacenzian (about 3 million years ago) to assess the potential environmental and economic impacts to population centers along the US Atlantic coast under different rates and magnitudes of changes related to warmer temperatures. Specifically, we look at past...

Wetlands accumulate organic-rich sediment or peat stratigraphically, making them great archives of past environmental change. Wetlands also act as hydrologic buffers on the landscape and are important to global biogeochemical cycling. This project uses wetland archives from a range of environments to better understand how vegetation, hydrology, and hydroclimate has changed on decadal to multi...

Sudden and extreme global warming events of the past are known as hyperthermals. The most intensely studied of these is the Paleocene-Eocene Thermal Maximum (PETM) that occurred about 56 million years ago. During the PETM, global temperatures rose by ~5°C, ocean acidification was widespread, floral and faunal communities were severely disrupted, and changing oceanic circulation and a disrupted...