Climate and Environmental Change in the Gulf of Mexico and Caribbean
Science Center Objects
This project documents paleoceanographic, climatic, and environmental changes in the Gulf of Mexico and adjacent land areas over the last 10,000 years. The paleoenvironmental data is used to determine rates of change in the past, and to better understand both the natural and anthropogenic factors that contribute to climate variability on inter-annual to millennial timescales.
Multicores collected from the northern Gulf of Mexico while aboard the R/V Pelican in 2013. These cores are sampled at 5 mm increments and used to reconstruct sea surface temperature in the Gulf of Mexico over the past 1000 years. (Public domain.)
Paleoclimate Reconstruction from Marine and Lake Sediments
Highly-resolved records of past climate variability are increasingly important in light of the current need to differentiate between natural and anthropogenic climate change. Studies concentrate on the Holocene, the last 10,000 years. Analysis of microfossils, trace metal geochemistry, stable isotope geochemistry and biomarkers sediment cores is performed at sub-millennial to decadal resolution in sediment cores from lakes and the deep ocean.
Lauren Toth preparing to drill a coral reef framework core from Pulaski Shoal, Dry Tortugas National Park. (Credit: Julie Richey, USGS. Public domain.)
Coral Reefs as Climate Archives
Coral reefs are sentinels of climate change, responding to changes in water temperature, ocean pH, pollution and land use change near the coasts. This part of the project ties in closely with the CREST Project within the USGS Coastal and Marine Geology Program, and aims to reconstruct changes temperature, ocean circulation, sea level and the history of reef formation.
Total lipid extracts from particulate matter filtered from the surface to 14 meters water depth in Lake Tulane, located in Highlands County, Florida. These samples are part of a modern calibration study in the lake. (Public domain.)
Paleoceanographic Proxy Calibration
A sediment trap time series (2008-2018) in the northern Gulf of Mexico is used to assess environmental controls on sediment flux, microfossil assemblages, and the biogeochemistry of both molecular and calcium carbonate fossils. This information is used to improve calibrations, quantify uncertainties, and better understand the strengths and limitations of different paleoceanographic proxies in the Gulf of Mexico.
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Date published: March 7, 2018Status: ActivePaleoclimate Reconstruction from Marine and Lake Sediments
Instrumental measurements of climate variables (e.g., precipitation, temperature, ocean circulation, etc.) are only available over the past century or less. In order to quantify the rate and magnitude of natural climate variability going back in time beyond the 20th century, scientists rely on paleoclimate reconstructions.
Contacts: Julie Richey, Ph.D. -
Date published: February 27, 2018Status: ActivePaleoceanographic Proxy Calibration
A sediment trap time series in the northern Gulf of Mexico is used to better assess the control of environmental variables (e.g., temperature and salinity) on the flux of both microfossils and molecular fossils to the sediments. The information gained from sediment trap studies is used to develop better proxy-based estimates of past oceanographic conditions from analyses of microfossils and ...
Contacts: Julie Richey, Ph.D., Caitlin Reynolds -
Date published: March 28, 2018Coral Reefs as Climate Archives
USGS scientists use coral reefs as archives for reconstructing climate change during the Holocene (past 10,000 years). Coral reefs provide proxy information about rates of sea level change in the past, and individual coral colonies can be used to reconstruct the annual cycle of temperature and salinity variations for up to three centuries.
Contacts: Jennifer A FlanneryAttribution: St. Petersburg Coastal and Marine Science Center
Considerations for Globigerinoides ruber (white and pink) paleoceanography: Comprehensive insights from a long‐running sediment trap
We present a detailed analysis of the seasonal distribution, size, morphological variability and geochemistry of co‐occurring pink and white chromotypes of Globigerinoides ruberfrom a high‐resolution (1–2 weeks) and long‐running sediment trap time series in the northern Gulf of Mexico. We find no difference in the seasonal flux of the two...
Richey, Julie N.; Thirumalai, Kaustubh; Khider, Deborah; Reynolds, Caitlin E.; Partin, Judson W.; Quinn, Terrence M. Quantifying uncertainty in Sr/Ca-based estimates of SST from the coral Orbicella faveolata
The strontium to calcium ratio (Sr/Ca) in aragonitic skeletons of massive corals provides a proxy for sea surface temperature (SST) that can be used to reconstruct paleoclimates across decades, centuries, and, potentially, millennia. Determining the reproducibility of Sr/Ca records among contemporaneous coral colonies from the same region is...
Flannery, Jennifer A.; Richey, Julie N.; Toth, Lauren T.; Kuffner, Ilsa B.; Poore, Richard Z. 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. 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.
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 Lunar periodicity in the shell flux of planktonic foraminifera in the Gulf of Mexico
Synchronised reproduction offers clear benefits to planktonic foraminifera – an important group of marine calcifiers – as it increases the chances of successful gamete fusion. Such synchrony requires tuning to an internal or external clock. Evidence exists for lunar reproductive cycles in some species, but its recognition in shell flux...
Jonkers, Lukas; Reynolds, Caitlin E.; Richey, Julie N.; Hall, Ian R. Globigerinoides ruber morphotypes in the Gulf of Mexico: a test of null hypothesis
Planktic foraminifer Globigerinoides ruber (G. ruber), due to its abundance and ubiquity in the tropical/subtropical mixed layer, has been the workhorse of paleoceanographic studies investigating past sea-surface conditions on a range of timescales. Recent geochemical work on the two principal white G. ruber (W) morphotypes, sensu stricto (ss) and...
Thirumalai, Kaustubh; Richey, Julie N.; Quinn, Terrence M.; Poore, Richard Z.
Weekly resolution particulate flux from a sediment trap in the northern Gulf of Mexico, 2008-2012
The U.S. Geological Survey anchored a sediment trap in the northern Gulf of Mexico to collect time-series data on sediment flux from 2008 to 2012. There are continuous measurements of total mass flux and organic carbon flux (ogC) at 7–14 day resolution from 2008 to 2012. The flux of calcium carbonate (CaCO3), particulate nitrogen (nitro), and...
Richey, Julie N.; Reynolds, Caitlin E.; Tappa, Eric; Thunell, Robert
Seasonal flux and assemblage composition of planktic foraminifera from the northern Gulf of Mexico, 2008-2012
The U.S. Geological Survey anchored a sediment trap in the northern Gulf of Mexico beginning in 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 results from 2012. Ten species, or varieties, constituted ~92...
Reynolds, Caitlin E.; Richey, Julie N.; Poore, Richard Z.
Seasonal flux and assemblage composition of planktic foraminifera from the northern Gulf of Mexico, 2008-11
The U.S. Geological Survey anchored a sediment trap in the northern Gulf of Mexico 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 results from 2011. Ten species, or varieties, constituted ~92 percent of the 2011...
Reynolds, Caitlin E.; Poore, Richard Z.-
Date published: December 16, 2016Sediment Trap Time Series of GDGT and alkenone flux in the Gulf of Mexico
The tetraether index of C86 (TEX86) and alkenone unsaturation index (Uk37Õ) molecular biomarker proxies have been broadly applied in down-core marine sediments to reconstruct past sea surface temperature (SST). Although both TEX86 and Uk37 have been interpreted as proxies for mean annual SST throughout the global ocean, regional studies of glycerol dibiphytanyl glycerol tetraethers (GDGT)s and...
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Date published: April 6, 2018
Globorotalia truncatulinoides Sediment Trap Data in the Gulf of Mexico
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 flux occurs in winter (January, February, and March), and that encrusted and non-...