Thunell Robert C.

Last Name

Thunell

First Name

Robert C.

Full item page

Search Results

Now showing 1 - 12 of 12

CARIACO time series individual CTD profiles from B/O Hermano Gines HG93_CARIACO in the CARIACO basin from 1995-2017 (CARIACO project)

(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-07-17) Muller-Karger, Frank ; Astor, Yrene ; Benitez-Nelson, Claudia ; Buck, Kristen N. ; Fanning, Kent ; Scranton, Mary I. ; Taylor, Gordon T. ; Thunell, Robert C. ; Varela, Ramon ; Capelo, Juan ; Gutierrez, Javier ; Guzman, Laurencia ; Lorenzoni, Laura ; Montes, Enrique ; Rojas, Jaimie ; Rondon, Anadiuska ; Rueda-Roa, Digna

This collection of data comprises all the Individual CTD profiles from the Cariaco basin taken as part of the CARIACO Ocean Time-Series Program from November 1995 to January 2017. These include all the CTD profiles taken during the monthly hydrographic cruises at the CARIACO station (10.50° N, 64.67° W), as well as other CTD profiles from extra legs of the monthly cruises, and few spatial cruises collected in and around the Cariaco basin. CTD’s Salinity and Oxygen where calibrated with in-situ measurements (see Acquisition Description). This dataset is complimentary to the monthly “CTD Composite Profiles” (https://www.bco-dmo.org/dataset/3092), and many fields are very similar to that data-base. The difference with that dataset, is that here we present all the CTD casts for each cruise, the CTD profiles are single (not composite), and the salinity and oxygen profiles were calibrated with in-situ measurements, but fluorescence was no calibrated. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/773146
Time series HPLC pigment data as measured by the NASA Goddard Space Flight Center from B/O Hermano Gines cruises CAR-176 to CAR-232 in the CARIACO basin from 2011-01-11 through 2017-01-12 (CARIACO Ocean Time-Series Program)

(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-09-27) Muller-Karger, Frank ; Astor, Yrene ; Scranton, Mary I. ; Taylor, Gordon T. ; Thunell, Robert C. ; Troccoli, Luis ; Varela, Ramon

The CARIACO Ocean Time-Series Program (formerly known as CArbon Retention In A Colored Ocean) started on November 1995 (CAR-001) and ended on January 2017 (CAR-232). Throughout the CARIACO time-series, High Performance Liquid Chromatography (HPLC) data was analyzed by four different laboratories: Bermuda Biological Research Station; Mote Marine Laboratory; Horn Point Laboratory; and NASA Goddard Space Flight Center. This package contains the data analyzed at the NASA Goddard Space Flight Center, covering cruises CAR-176 to CAR-232 from 2011-01-11 to 2017-01-12. Some of the parameters analyzed were different along time and along the different laboratories. To keep the continuity of the HPLC time-series analyzed by different laboratories, all the HPLC files have the same units and contain the same number and order of columns/parameters (with “nd” to indicate when a parameter was no determined). Fluorometric Chlorophyll-a and Phaeopigments (measured at Estación de Investigaciones Marinas de Margarita, Fundación La Salle, EDIMAR-FLASA) are also included. HPLC was not analyzed for cruises CAR-069 to CAR-123. A general description of the CARIACO Ocean Time-Series Program can be found at www.imars.usf.edu/cariaco. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/777689
Time series HPLC pigment data as measured by the Bermuda Biological Research Station (BBRS) from B/O Hermano Gines cruises CAR-002 to CAR-030 in the CARIACO basin from 1995-12-13 through 1998-04-21 (CARIACO Ocean Time-Series Program)

(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-09-27) Muller-Karger, Frank ; Astor, Yrene ; Scranton, Mary I. ; Taylor, Gordon T. ; Thunell, Robert C. ; Troccoli, Luis ; Varela, Ramon

The CARIACO Ocean Time-Series Program (formerly known as CArbon Retention In A Colored Ocean) started on November 1995 (CAR-001) and ended on January 2017 (CAR-232). Throughout the CARIACO time-series, High Performance Liquid Chromatography (HPLC) data was analyzed by four different laboratories: Bermuda Biological Research Station; Mote Marine Laboratory; Horn Point Laboratory; and NASA Goddard Space Flight Center. This package contains the data analyzed at the Bermuda Biological Research Station, covering cruises CAR-002 to CAR-030 from 1995-12-13 to 1998-04-21. Some of the parameters analyzed were different along time and along the different laboratories. To keep the continuity of the HPLC time-series analyzed by different laboratories, all the HPLC files have the same units and contain the same number and order of columns/parameters (with “nd” to indicate when a parameter was no determined). Fluorometric Chlorophyll-a and Phaeopigments (measured at Estación de Investigaciones Marinas de Margarita, Fundación La Salle, EDIMAR-FLASA) are also included. HPLC was not analyzed for cruises CAR-069 to CAR-123. A general description of the CARIACO Ocean Time-Series Program can be found at www.imars.usf.edu/cariaco. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/3293
Time-series Niskin-bottle sample data from R/V Hermano Gines cruises in the Cariaco Basin from 1995 through 2017 (CARIACO Ocean Time-Series Program)

(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-06-07) Muller-Karger, Frank ; Astor, Yrene ; Scranton, Mary I. ; Taylor, Gordon T. ; Thunell, Robert C. ; Varela, Ramon ; Benitez-Nelson, Claudia ; Buck, Kristen N. ; Fanning, Kent ; Capelo, Juan ; Gutierrez, Javier ; Guzman, Laurencia ; Lorenzoni, Laura ; Montes, Enrique ; Rojas, Jaimie ; Rondon, Anadiuska ; Rueda-Roa, Digna ; Tappa, Eric

The CARIACO Ocean Time-Series Program (formerly known as CArbon Retention In A Colored Ocean) started on November 1995 (CAR-001) and ended on January 2017 (CAR-232). Monthly cruises were conducted to the CARIACO station (10.50° N, 64.67° W) onboard the R/V Hermano Ginés of the Fundación La Salle de Ciencias Naturales de Venezuela. During each cruise, a minimum of four hydrocasts were performed to collect a suite of core monthly observations. We conducted separate shallow and deep casts to obtain a better vertical resolution of in-situ Niskin-bottles samples for chemical observations, and for productivity, phytoplankton, and pigment observations. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/3093
Time series HPLC pigment data as measured by MOTE Marine Laboratory & Aquarium from B/O Hermano Gines cruises CAR-031 to CAR-068 in the CARIACO basin from 1998-06-09 to 2001-07-10 (CARIACO Ocean Time-Series Program)

(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-09-27) Muller-Karger, Frank ; Astor, Yrene ; Scranton, Mary I. ; Taylor, Gordon T. ; Thunell, Robert C. ; Troccoli, Luis ; Varela, Ramon

The CARIACO Ocean Time-Series Program (formerly known as CArbon Retention In A Colored Ocean) started on November 1995 (CAR-001) and ended on January 2017 (CAR-232). Throughout the CARIACO time-series, High Performance Liquid Chromatography (HPLC) data was analyzed by four different laboratories: Bermuda Biological Research Station; Mote Marine Laboratory; Horn Point Laboratory; and NASA Goddard Space Flight Center. This package contains the data analyzed at the MOTE Marine Laboratory & Aquarium, covering cruises CAR-031 to CAR-068 from 1998-06-09 to 2001-07-10. Some of the parameters analyzed were different along time and along the different laboratories. To keep the continuity of the HPLC time-series analyzed by different laboratories, all the HPLC files have the same units and contain the same number and order of columns/parameters (with “nd” to indicate when a parameter was no determined). Fluorometric Chlorophyll-a and Phaeopigments (measured at Estación de Investigaciones Marinas de Margarita, Fundación La Salle, EDIMAR-FLASA) are also included. HPLC was not analyzed for cruises CAR-069 to CAR-123. A general description of the CARIACO Ocean Time-Series Program can be found at www.imars.usf.edu/cariaco. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/3292
Time series HPLC pigment data as measured by Horn Point Laboratory (HPL) from B/O Hermano Gines cruises CAR-124 to CAR-175 in the CARIACO basin from 2006-07-04 to 2010-12-08 (CARIACO Ocean Time-Series Program)

(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-09-27) Muller-Karger, Frank ; Astor, Yrene ; Scranton, Mary I. ; Taylor, Gordon T. ; Thunell, Robert C. ; Troccoli, Luis ; Varela, Ramon

The CARIACO Ocean Time-Series Program (formerly known as CArbon Retention In A Colored Ocean) started on November 1995 (CAR-001) and ended on January 2017 (CAR-232). Throughout the CARIACO time-series, High Performance Liquid Chromatography (HPLC) data was analyzed by four different laboratories: Bermuda Biological Research Station; Mote Marine Laboratory; Horn Point Laboratory; and NASA Goddard Space Flight Center. This package contains the data analyzed at Horn Point Laboratory, covering cruises CAR-124 to CAR-175 from 2006-07-04 to 2010-12-08. Some of the parameters analyzed were different along time and along the different laboratories. To keep the continuity of the HPLC time-series analyzed by different laboratories, all the HPLC files have the same units and contain the same number and order of columns/parameters (with “nd” to indicate when a parameter was no determined). Fluorometric Chlorophyll-a and Phaeopigments (measured at Estación de Investigaciones Marinas de Margarita, Fundación La Salle, EDIMAR-FLASA) are also included. HPLC was not analyzed for cruises CAR-069 to CAR-123. A general description of the CARIACO Ocean Time-Series Program can be found at www.imars.usf.edu/cariaco. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/3235
Western Arctic Ocean temperature variability during the last 8000 years

(American Geophysical Union, 2011-12-17) Farmer, Jesse R. ; Cronin, Thomas M. ; de Vernal, Anne ; Dwyer, Gary S. ; Keigwin, Lloyd D. ; Thunell, Robert C.

We reconstructed subsurface (∼200–400 m) ocean temperature and sea-ice cover in the Canada Basin, western Arctic Ocean from foraminiferal δ18O, ostracode Mg/Ca ratios, and dinocyst assemblages from two sediment core records covering the last 8000 years. Results show mean temperature varied from −1 to 0.5°C and −0.5 to 1.5°C at 203 and 369 m water depths, respectively. Centennial-scale warm periods in subsurface temperature records correspond to reductions in summer sea-ice cover inferred from dinocyst assemblages around 6.5 ka, 3.5 ka, 1.8 ka and during the 15th century Common Era. These changes may reflect centennial changes in the temperature and/or strength of inflowing Atlantic Layer water originating in the eastern Arctic Ocean. By comparison, the 0.5 to 0.7°C warm temperature anomaly identified in oceanographic records from the Atlantic Layer of the Canada Basin exceeded reconstructed Atlantic Layer temperatures for the last 1200 years by about 0.5°C.
The Medieval Climate Anomaly and Little Ice Age in Chesapeake Bay and the North Atlantic Ocean

(Elsevier B.V., 2010-08-22) Cronin, Thomas M. ; Hayo, K. ; Thunell, Robert C. ; Dwyer, Gary S. ; Saenger, Casey P. ; Willard, Debra. A.

A new 2400-year paleoclimate reconstruction from Chesapeake Bay (CB) (eastern US) was compared to other paleoclimate records in the North Atlantic region to evaluate climate variability during the Medieval Climate Anomaly (MCA) and Little Ice Age (LIA). Using Mg/Ca ratios from ostracodes and oxygen isotopes from benthic foraminifera as proxies for temperature and precipitation-driven estuarine hydrography, results show that warmest temperatures in CB reached 16–17 °C between 600 and 950 CE (Common Era), centuries before the classic European Medieval Warm Period (950–1100 CE) and peak warming in the Nordic Seas (1000–1400 CE). A series of centennial warm/cool cycles began about 1000 CE with temperature minima of ~ 8 to 9 °C about 1150, 1350, and 1650–1800 CE, and intervening warm periods (14–15 °C) centered at 1200, 1400, 1500 and 1600 CE. Precipitation variability in the eastern US included multiple dry intervals from 600 to 1200 CE, which contrasts with wet medieval conditions in the Caribbean. The eastern US experienced a wet LIA between 1650 and 1800 CE when the Caribbean was relatively dry. Comparison of the CB record with other records shows that the MCA and LIA were characterized by regionally asynchronous warming and complex spatial patterns of precipitation, possibly related to ocean–atmosphere processes.
Anomalous delta C-13 in particulate organic carbon at the chemoautotrophy maximum in the Cariaco Basin

(Journal of Geophysical Research-Biogeosciences, 2020-01-30) Scranton, Mary I. ; Taylor, Gordon T. ; Thunell, Robert C. ; Muller-Karger, Frank E. ; Astor, Yrene ; Swart, Peter K. ; Edgcomb, Virginia P. ; Pachiadaki, Maria G.

A chemoautotrophy maximum is present in many anoxic basins at the sulfidic layer's upper boundary, but the factors controlling this feature are poorly understood. In 13 of 31 cruises to the Cariaco Basin, particulate organic carbon (POC) was enriched in 13C (δ13CPOC as high as −16‰) within the oxic/sulfidic transition compared to photic zone values (−23 to −26‰). During “heavy” cruises, fluxes of O2 and [NO3− + NO2−] to the oxic/sulfidic interface were significantly lower than during “light” cruises. Cruises with isotopically heavy POC were more common between 2013 and 2015 when suspended particles below the photic zone tended to be nitrogen rich compared to later cruises. Within the chemoautotrophic layer, nitrogen‐rich particles (molar ratio C/N< 10) were more likely to be 13C‐enriched than nitrogen‐poor particles, implying that these inventories were dominated by living cells and fresh detritus rather than laterally transported or extensively decomposed detritus. During heavy cruises, 13C enrichments persisted to 1,300 m, providing the first evidence of downward transport of chemoautotrophically produced POC. Dissolved inorganic carbon assimilation during heavy cruises (n = 3) was faster and occurred deeper than during light cruises (n = 2). Metagenomics data from the chemoautotrophic layer during two cruises support prevalence of microorganisms carrying RuBisCO form II genes, which encode a carbon fixation enzyme that discriminates less against heavy isotopes than most other carbon fixation enzymes, and metatranscriptomics data indicate that higher expression of form II RuBisCO genes during the heavy cruises at depths where essential reactants coexist are responsible for the isotopically heavier POC.
Rapid sea level rise and ice sheet response to 8,200-year climate event

(American Geophysical Union, 2007-10-24) Cronin, Thomas M. ; Vogt, P. R. ; Willard, Debra A. ; Thunell, Robert C. ; Halka, J. ; Berke, M. ; Pohlman, John W.

The largest abrupt climatic reversal of the Holocene interglacial, the cooling event 8.6–8.2 thousand years ago (ka), was probably caused by catastrophic release of glacial Lake Agassiz-Ojibway, which slowed Atlantic meridional overturning circulation (AMOC) and cooled global climate. Geophysical surveys and sediment cores from Chesapeake Bay reveal the pattern of sea level rise during this event. Sea level rose ~14 m between 9.5 to 7.5 ka, a pattern consistent with coral records and the ICE-5G glacio-isostatic adjustment model. There were two distinct periods at ~8.9–8.8 and ~8.2–7.6 ka when Chesapeake marshes were drown as sea level rose rapidly at least ~12 mm yr−1. The latter event occurred after the 8.6–8.2 ka cooling event, coincided with extreme warming and vigorous AMOC centered on 7.9 ka, and may have been due to Antarctic Ice Sheet decay.
Deepwater expansion and enhanced remineralization in the eastern equatorial Pacific during the last glacial maximum

(John Wiley & Sons, 2018-06-04) Umling, Natalie E. ; Thunell, Robert C. ; Bizimis, Michael

Published estimates of the radiocarbon content of middepth waters suggest a decrease in ventilation in multiple locations during the last glacial maximum (LGM; 24.0–18.1 ka). Reduced glacial ventilation would have allowed respired carbon to accumulate in those waters. A subsequent deglacial release of this respired carbon reservoir to the atmosphere could then account for the observed increases in atmospheric CO2 and decline in atmospheric radiocarbon content. However, age model error and a release of 14C‐depleted mantle carbon have also been cited as possible explanations for the observed middepth radiocarbon depletions, calling into question the deep ocean's role in storing respired carbon during the LGM. Joint measurements of benthic foraminiferal carbon isotope values (δ13C) and cadmium/calcium (Cd/Ca) ratios provide a method for isolating the air‐sea component of a water mass from changes in remineralization. Here we use benthic foraminiferal δ13C and Cd/Ca records from the eastern equatorial Pacific to constrain changes in remineralization and water‐mass mixing over the last glacial‐interglacial transition. These records are complemented with elemental measurements of the authigenic coatings of foraminifera to monitor postdepositional changes in bottom water properties. Our results suggest an increase of deep waters at midwater depths consistent with a shoaling of the boundary between the upper and lower branches of Southern Ocean overturning circulation. Additionally, our records demonstrate increased organic matter remineralization in middepth waters during the LGM, suggesting that respired carbon did accumulate in middepth waters under periods of reduced ventilation.
Time series composite CTD profiles from R/V Hermano Ginés cruises in the Cariaco Basin from 1995 through 2017 (CARIACO Ocean Time-Series Program)

(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-06-06) Muller-Karger, Frank ; Astor, Yrene ; Benitez-Nelson, Claudia ; Scranton, Mary I. ; Taylor, Gordon T. ; Thunell, Robert C. ; Varela, Ramon ; Capelo, Juan ; Guzman, Laurencia ; Lorenzoni, Laura ; Montes, Enrique ; Rojas, Jaimie ; Rueda-Roa, Digna

The CARIACO Ocean Time-Series Program (formerly known as CArbon Retention In A Colored Ocean) started on November 1995 (CAR-001) and ended on January 2017 (CAR-232). Monthly cruises were conducted to the CARIACO station (10.50° N, 64.67° W) onboard the R/V Hermano Ginés of the Fundación La Salle de Ciencias Naturales de Venezuela. During each cruise, a minimum of four hydrocasts were performed to collect a suite of core monthly observations. We conducted separate shallow and deep casts to obtain a better vertical resolution of in-situ Niskin-bottles samples for chemical observations, and for productivity, phytoplankton, and pigment observations. One CTD composite profile was created for each cruise by stitching together the sections of the different cruise's CTD profiles at the depth interval where water samples were obtained. CTD’s Salinity, Oxygen, and Fluorescence where calibrated with in-situ measurements. The composite CTD profiles dataset is a complement of the hydrographic time series data obtained with the Niskin Bottle Samples (https://www.bco-dmo.org/dataset/3093). The following sections describe the methods used in collecting the core observations at the CARIACO station. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/3092

Thunell Robert C.

Last Name

First Name

ORCID

Filters

Author

Subject

Date

Type

Has files

Settings

Sort By

Results per page

Search Results