Julie Richey, Ph.D.
Paleoclimate and Environmental Change
Establishing a baseline of natural climate variability over the past 2,000 years is essential to accurately predicting regional responses to anthropogenic climate change. My research focus is reconstructing temperature and hydroclimatic variability in the Gulf of Mexico/Subtropical Atlantic Ocean using a broad range of different paleoclimate archives. In addition to generating proxy-based paleoclimate records, I am working on proxy development and calibration studies to improve our ability to quantify past changes in temperature, salinity and precipitation in both terrestrial and marine environments.
- Using stable isotopes and trace elements to reconstruct climate from coral skeletons
- Investigating the effect of water quality and coral ecology on geochemical proxies
- US Virgin Islands
- Dry Tortugas National Park
- Florida Keys Reef Tract
Project web page: http://coastal.er.usgs.gov/crest/research-themes/climate.html
Holocene Paleoclimate in the Gulf of Mexico
- Calibration of paleocenographic proxies using Sediment Trap in the northern Gulf of Mexico
- Generating high-resolution records of sea surface temperature in the northern Gulf of Mexico using foraminiferal Mg/Ca
- Garrison Basin (Gulf of Mexico)
- Fisk Basin (Gulf of Mexico)
- Pigmy Basin (Gulf of Mexico)
- Sediment Trap Site (Gulf of Mexico)
- Ph. D. - Marine Geology (2010), Univ. of South Florida, College of Marine Science
- M.S. - Marine Geology (2007), Univ. of South Florida, College of Marine Science
- B.S. - Geological Sciences/Biological Sciences (2004), The Ohio State Univ.
Google Scholar Profile: https://scholar.google.com/citations?user=595LDgUAAAAJ&hl=en&oi=ao
Science and Products
The specific objectives of this project are to identify and describe the processes that are important in determining rates of coral-reef construction. How quickly the skeletons of calcifying organisms accumulate to form massive barrier-reef structure is determined by processes of both construction (how fast organisms grow and reproduce) and destruction (how fast reefs break down by mechanical...
Ecosystem-wide study of seafloor erosion, changing coastal water depths, and effects on coastal storm and wave impacts along the Florida Keys Coral Reef Tract in South Florida.
Environmental controls on the geochemistry of Globorotalia truncatulinoides in the Gulf of Mexico: Implications for paleoceanographic reconstructions
Modern observations of planktic foraminifera from sediment trap studies help to constrain the regional ecology of paleoceanographically valuable species. Results from a weekly-resolved sediment trap time series (2008–2014) in the northern Gulf of Mexico demonstrate that 92% of Globorotalia truncatulinoides ...Reynolds, Caitlin E.; Richey, Julie N.; Fehrenbacher, Jennifer S.; Rosenheim, Brad E.; Spero, Howard J.
A North American Hydroclimate Synthesis (NAHS) of the Common Era
This study presents a synthesis of century-scale hydroclimate variations in North America for the Common Era (last 2000 years) using new age models of previously published multiple proxy-based paleoclimate data. This North American Hydroclimate Synthesis (NAHS) examines regional hydroclimate patterns and related environmental indicators,...Rodysill, Jessica R. ; Anderson, Lesleigh; Cronin, Thomas M.; Jones, Miriam C.; Thompson, Robert S.; Wahl, David B.; Willard, Debra A.; Addison, Jason A.; Alder, Jay R.; Anderson, Katherine H.; Anderson, Lysanna; Barron, John A.; Bernhardt, Christopher E.; Hostetler, Steven W.; Kehrwald, Natalie M.; Khan, Nicole; Richey, Julie N.; Starratt, Scott W.; Strickland, Laura E.; Toomey, Michael; Treat, Claire C.; Wingard, G. Lynn
Pronounced centennial-scale Atlantic Ocean climate variability correlated with Western Hemisphere hydroclimate
Surface-ocean circulation in the northern Atlantic Ocean influences Northern Hemisphere climate. Century-scale circulation variability in the Atlantic Ocean, however, is poorly constrained due to insufficiently-resolved paleoceanographic records. Here we present a replicated reconstruction of sea-surface temperature and salinity from a site...Thirumalai, Kaustubh; Quinn, Terrence M.; Okumura, Yuko; Richey, Julie N.; Partin, Judson W.; Poore, Richard Z.; Moreno-Chamarro, Eduardo
Millennial-scale variability in the local radiocarbon reservoir age of south Florida during the Holocene
A growing body of research suggests that the marine environments of south Florida provide a critical link between the tropical and high-latitude Atlantic. Changes in the characteristics of water masses off south Florida may therefore have important implications for our understanding of climatic and oceanographic variability over a broad spatial...Toth, Lauren T.; Cheng, Hai; Edwards, R. Lawrence; Ashe, Erica; Richey, Julie N.
Fidelity of the Sr/Ca proxy in recording ocean temperature in the western Atlantic coral Siderastrea siderea
Massive corals provide a useful archive of environmental variability, but careful testing of geochemical proxies in corals is necessary to validate the relationship between each proxy and environmental parameter throughout the full range of conditions experienced by the recording organisms. Here we use samples from a coral-growth study to test the...Kuffner, Ilsa B.; Roberts, Kelsey E.; Flannery, Jennifer A.; Morrison, Jennifer M.; Richey, Julie N.
Multi-species coral Sr/Ca-based sea-surface temperature reconstruction using Orbicella faveolata and Siderastrea siderea from the Florida Straits
We present new, monthly-resolved Sr/Ca-based sea-surface temperature (SST) records from two species of massive coral, Orbicella faveolata and Siderastrea siderea, from the Dry Tortugas National Park, FL, USA (DTNP). We combine these new records with published data from three additional S. siderea coral colonies to generate a 278-year long multi-...Flannery, Jennifer A.; Richey, Julie N.; Thirumalai, Kaustubh; Poore, Richard Z.; DeLong, Kristine L.
GDGT and alkenone flux in the northern Gulf of Mexico: Implications for the TEX86 and UK137 paleothermometers
The TEX86 and molecular biomarker proxies have been broadly applied in down-core marine sediments to reconstruct past sea surface temperature (SST). Although both TEX86 and have been interpreted as proxies for mean annual SST throughout the global ocean, regional studies of GDGTs and alkenones in sinking particles are required to understand the...Richey, Julie N.; Tierney, Jessica E.
Data for evaluating the Sr/Ca temperature proxy with in-situ temperature in the western Atlantic coral Siderastrea siderea
Massive corals are used as environmental recorders throughout the tropics and subtropics to study environmental variability during time periods preceding ocean-observing instrumentation. However, careful testing of paleoproxies is necessary to validate the environmental-proxy record throughout a range of conditions experienced by the recording...Kuffner, Ilsa B.; Roberts, Kelsey E.; Flannery, Jennifer A.; Morrison, Jennifer M.; Richey, Julie
GDGT and alkenone flux in the northern Gulf of Mexico
This dataset is a weekly to bi-weekly resolution 4-year time series (2010-2014) of GDGT and alkenone flux in the northern Gulf of Mexico. The TEX86 and U37K' indices are also included, which are sea surface temperature proxies based on the distribution of GDGTs and alkenones, respectively. For further information regarding data collection and/or...Richey, Julie; Tierney, Jessica E.
Precipitation changes in the western tropical Pacific over the past millennium
Modern seasonal and inter-annual precipitation variability in Palau is linked to both meridional movement of the Intertropical Convergence Zone (ITCZ) and changes in the Pacific Walker Circula- tion (PWC) associated with the El Niño–Southern Oscillation. Thus, Palau’s hydroclimate should be sensitive to mean shifts in the ITCZ and PWC on decadal...Richey, Julie N.; Sachs, Julian P.
Seasonal flux and assemblage composition of planktic foraminifera from the northern Gulf of Mexico, 2008–14
The U.S. Geological Survey anchored a sediment trap in the northern Gulf of Mexico in January 2008 to collect seasonal time-series data on the flux and assemblage composition of live planktic foraminifers. This report provides an update of the previous time-series data to include continuous results from January 2013 through May 2014. Ten taxa...Reynolds, Caitlin E.; Richey, Julie N.
The relationship between the ratio of strontium to calcium and sea-surface temperature in a modern Porites astreoides coral: Implications for using P. astreoides as a paleoclimate archive
An inverse relationship has been demonstrated between water temperature and the ratio of strontium to calcium (Sr/Ca) in coral aragonite for a number of Pacific species of the genus Porites. This empirically determined relationship has been used to reconstruct past sea-surface temperature (SST) from modern and Holocene age coral archives. A study...Tess E. Busch; Flannery, Jennifer A.; Richey, Julie N.; Stathakopoulos, Anastasios