Thomas Cronin, Ph.D.
Thomas Cronin is a Senior Geologist at the Florence Bascom Geoscience Center.
Dr. Cronin received his BA from Colgate University in Geology in 1972 and MA and PhD in Geology from Harvard University in 1974 and 1977.
Positions: National Research Council Post-doc at the USGS at the Museum of Natural History, Washington DC 1977-1978, research scientist USGS since 1978. NSF-sponsored visiting researcher at Shizuoka University, Japan (1991), lecturer Urbino (Italy) Summer School for Paleoclimatology Faculty (2009-2016), adjunct faculty Georgetown University’s Walsh School of Foreign Service (2005-present), White House Office of Science, Technology and Policy (OSTP) (1996-97).
US Geological Survey research in paleoclimatology, sea-level change, biostratigraphy, geochemistry and ecosystems; more than co-authored 200 scientific articles, more than 60 journals including Science, Nature, Nature Geoscience, Proceedings National Academy of Sciences, Geology, Geophysical Research Letters, Trends in Ecology and Evolution, and Quaternary Science Reviews. Numerous invited articles to proceedings volumes, handbooks & encyclopedias. Written two books, former co-editor of Global & Planetary Change, editorial boards for Journal of Micropaleontology, Marine Micropaleontology, Journal of Paleontology. Frequent manuscript reviews for international journals, proposals to National Science Foundation and other agencies.
In addition to work at OSTP, served on numerous USGS and interagency scientific committees and panels, contributing to USGS program development and informing decision-makers and the public. Published influential studies in the fields of micropaleontology, sea level and climate change, paleoceanography, and ecosystem history. Honors: Brady Medal (TMS London), Duke of Montefeltro Medal (USSP Urbino), Fellow, American Association for Advancement of Science, Wilmot H. Bradley lecture (Geological Society Washington), US Coast Guard Service Medal, AGU Citation for Excellence Reviewing, Bolin Climate Center Annual Lecturer (Stockholm), USGS Leadership, Meritorious Service, and Excellence Awards. Research widely reported in media including NY Times, National Geographic Society, New Scientist, Chesapeake Bay Journal, BBC, NPR, AP, and Fox News. Collaboration with major research institutions across the US, Europe and Asia, mentored numerous bachelors, masters and PhD students.
Current research focused on Land-Sea Linkages in the Arctic, Arctic paleoclimatology and sea-level change. Participated in four Arctic icebreaker research expeditions recovering sediment cores of the last million years of Arctic Ocean history. Work has influenced US Department of Homeland Security, US Coast Guard icebreaker planning, NOAA’s Arctic Program, and the International Ocean Drilling Program deep-sea coring program.
Science and Products
Filter Total Items: 128
The Medieval Climate Anomaly and Little Ice Age in Chesapeake Bay and the North Atlantic Ocean
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 hyd
Authors
T. M. Cronin, K. Hayo, R.C. Thunell, G. S. Dwyer, C. Saenger, D. A. Willard
Quaternary Sea-ice history in the Arctic Ocean based on a new Ostracode sea-ice proxy
Paleo-sea-ice history in the Arctic Ocean was reconstructed using the sea-ice dwelling ostracode Acetabulastoma arcticum from late Quaternary sediments from the Mendeleyev, Lomonosov, and Gakkel Ridges, the Morris Jesup Rise and the Yermak Plateau. Results suggest intermittently high levels of perennial sea ice in the central Arctic Ocean during Marine Isotope Stage (MIS) 3 (25-45 ka), minimal sea
Authors
T. M. Cronin, L. Gemery, W.M. Briggs, M. Jakobsson, L. Polyak, E. M. Brouwers
Temporal latitudinal-gradient dynamics and tropical instability of deep-sea species diversity
A benthic microfaunal record from the equatorial Atlantic Ocean over the past four glacial-interglacial cycles was investigated to understand temporal dynamics of deep-sea latitudinal species diversity gradients (LSDGs). The results demonstrate unexpected instability and high amplitude fluctuations of species diversity in the tropical deep ocean that are correlated with orbital-scale oscillations
Authors
Moriaki Yasuhara, G. Hunt, T. M. Cronin, H. Okahashi
Morphological variability of the planktonic foraminifer Neogloboquadrina pachyderma from ACEX cores: Implications for late pleistocene circulation in the Arctic Ocean
Planktonic foraminifera populations were studied throughout the top 25 meters of the IODP ACEX 302 Hole 4C from the central Arctic Ocean at a resolution varying from 5cm (at the top of the record) to 10cm. Planktonic foraminifera occur in high absolute abundances only in the uppermost fifty centimetres and are dominated by the taxa Neogloboquadrina pachyderma. Except for a few intermittent layers
Authors
F. Eynaud, T. M. Cronin, S.A. Smith, S. Zaragosi, J. Mavel, Y. Mary, V. Mas, C. Pujol
Deep-sea ostracods from the South Atlantic sector of the Southern ocean during the Last 370,000 years
We report changes of deep-sea ostracod fauna during the last 370,000 yr from the Ocean Drilling Program (ODP) Hole 704A in the South Atlantic sector of the Southern Ocean. The results show that faunal changes are coincident with glacial/interglacial-scale deep-water circulation changes, even though our dataset is relatively small and the waters are barren of ostracods until mid-MIS (Marine Isotope
Authors
Moriaki Yasuhara, T. M. Cronin, G. Hunt, D.A. Hodell
Derivation of habitat-specific dissolved oxygen criteria for Chesapeake Bay and its tidal tributaries
The Chesapeake 2000 Agreement committed its state and federal signatories to “define the water quality conditions necessary to protect aquatic living resources” in the Chesapeake Bay (USA) and its tidal tributaries. Hypoxia is one of the key water quality issues addressed as a result of the above Agreement. This paper summarizes the protection goals and specific criteria intended to achieve those
Authors
Richard A. Batiuk, Denise L. Breitburg, Robert J. Diaz, Thomas M. Cronin, David H. Secor, Glen Thursby
Arctic climate change and its impacts on the ecology of the North Atlantic
Arctic climate change from the Paleocene epoch to the present is reconstructed with the objective of assessing its recent and future impacts on the ecology of the North Atlantic. A recurring theme in Earth's paleoclimate record is the importance of the Arctic atmosphere, ocean, and cryosphere in regulating global climate on a variety of spatial and temporal scales. A second recurring theme in this
Authors
Charles H. Greene, Andrew J. Pershing, Thomas M. Cronin, Nicole Ceci
Quaternary paleoceanography of the central Arctic based on Integrated Ocean Drilling Program Arctic Coring Expedition 302 foraminiferal assemblages
The Integrated Ocean Drilling Program (IODP) Arctic Coring Expedition (ACEX) Hole 4C from the Lomonosov Ridge in the central Arctic Ocean recovered a continuous 18 in record of Quaternary foraminifera yielding evidence for seasonally ice-free interglacials during the Matuyama, progressive development of large glacials during the mid-Pleistocene transition (MPT) ???1.2-0.9 Ma, and the onset of high
Authors
T. M. Cronin, S.A. Smith, F. Eynaud, M. O'Regan, J. King
Increased terrestrial to ocean sediment and carbon fluxes in the northern Chesapeake Bay associated with twentieth century land alteration
We calculated Chesapeake Bay (CB) sediment and carbon fluxes before and after major anthropogenic land clearance using robust monitoring, modeling and sedimentary data. Four distinct fluxes in the estuarine system were considered including (1) the flux of eroded material from the watershed to streams, (2) the flux of suspended sediment at river fall lines, (3) the burial flux in tributary sediment
Authors
C. Saenger, T. M. Cronin, D. Willard, J. Halka, R. Kerhin
Abyssal ostracods from the South and Equatorial Atlantic Ocean: Biological and paleoceanographic implications
We report the distribution of ostracods from ???5000 m depth from the Southeast and Equatorial Atlantic Ocean recovered from the uppermost 10 cm of minimally disturbed sediments taken by multiple-corer during the R/V Meteor DIVA2 expedition M63.2. Five cores yielded the following major deep-sea genera: Krithe, Henryhowella, Poseidonamicus, Legitimocythere, Pseudobosquetina, and Pennyella. All gene
Authors
Moriaki Yasuhara, T. M. Cronin, Arbizu P. Martinez
Abrupt climate change and collapse of deep-sea ecosystems
We investigated the deep-sea fossil record of benthic ostracodes during periods of rapid climate and oceanographic change over the past 20,000 years in a core from intermediate depth in the northwestern Atlantic. Results show that deep-sea benthic community "collapses" occur with faunal turnover of up to 50% during major climatically driven oceanographic changes. Species diversity as measured by t
Authors
Moriaki Yasuhara, T. M. Cronin, P.B. Demenocal, H. Okahashi, B.K. Linsley
Paleoecology and ecosystem restoration: Case studies from Chesapeake Bay and the Florida Everglades
Climate extremes that cause droughts, floods, or large temperature fluctuations can complicate ecosystem restoration efforts focused on local and regional human disturbance. Restoration targets are often based primarily on monitoring data and modeling simulations, which provide information on species' short-term response to disturbance and environmental variables. Consequently, the targets may be
Authors
Debra A. Willard, Thomas M. Cronin
Science and Products
Filter Total Items: 128
The Medieval Climate Anomaly and Little Ice Age in Chesapeake Bay and the North Atlantic Ocean
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 hyd
Authors
T. M. Cronin, K. Hayo, R.C. Thunell, G. S. Dwyer, C. Saenger, D. A. Willard
Quaternary Sea-ice history in the Arctic Ocean based on a new Ostracode sea-ice proxy
Paleo-sea-ice history in the Arctic Ocean was reconstructed using the sea-ice dwelling ostracode Acetabulastoma arcticum from late Quaternary sediments from the Mendeleyev, Lomonosov, and Gakkel Ridges, the Morris Jesup Rise and the Yermak Plateau. Results suggest intermittently high levels of perennial sea ice in the central Arctic Ocean during Marine Isotope Stage (MIS) 3 (25-45 ka), minimal sea
Authors
T. M. Cronin, L. Gemery, W.M. Briggs, M. Jakobsson, L. Polyak, E. M. Brouwers
Temporal latitudinal-gradient dynamics and tropical instability of deep-sea species diversity
A benthic microfaunal record from the equatorial Atlantic Ocean over the past four glacial-interglacial cycles was investigated to understand temporal dynamics of deep-sea latitudinal species diversity gradients (LSDGs). The results demonstrate unexpected instability and high amplitude fluctuations of species diversity in the tropical deep ocean that are correlated with orbital-scale oscillations
Authors
Moriaki Yasuhara, G. Hunt, T. M. Cronin, H. Okahashi
Morphological variability of the planktonic foraminifer Neogloboquadrina pachyderma from ACEX cores: Implications for late pleistocene circulation in the Arctic Ocean
Planktonic foraminifera populations were studied throughout the top 25 meters of the IODP ACEX 302 Hole 4C from the central Arctic Ocean at a resolution varying from 5cm (at the top of the record) to 10cm. Planktonic foraminifera occur in high absolute abundances only in the uppermost fifty centimetres and are dominated by the taxa Neogloboquadrina pachyderma. Except for a few intermittent layers
Authors
F. Eynaud, T. M. Cronin, S.A. Smith, S. Zaragosi, J. Mavel, Y. Mary, V. Mas, C. Pujol
Deep-sea ostracods from the South Atlantic sector of the Southern ocean during the Last 370,000 years
We report changes of deep-sea ostracod fauna during the last 370,000 yr from the Ocean Drilling Program (ODP) Hole 704A in the South Atlantic sector of the Southern Ocean. The results show that faunal changes are coincident with glacial/interglacial-scale deep-water circulation changes, even though our dataset is relatively small and the waters are barren of ostracods until mid-MIS (Marine Isotope
Authors
Moriaki Yasuhara, T. M. Cronin, G. Hunt, D.A. Hodell
Derivation of habitat-specific dissolved oxygen criteria for Chesapeake Bay and its tidal tributaries
The Chesapeake 2000 Agreement committed its state and federal signatories to “define the water quality conditions necessary to protect aquatic living resources” in the Chesapeake Bay (USA) and its tidal tributaries. Hypoxia is one of the key water quality issues addressed as a result of the above Agreement. This paper summarizes the protection goals and specific criteria intended to achieve those
Authors
Richard A. Batiuk, Denise L. Breitburg, Robert J. Diaz, Thomas M. Cronin, David H. Secor, Glen Thursby
Arctic climate change and its impacts on the ecology of the North Atlantic
Arctic climate change from the Paleocene epoch to the present is reconstructed with the objective of assessing its recent and future impacts on the ecology of the North Atlantic. A recurring theme in Earth's paleoclimate record is the importance of the Arctic atmosphere, ocean, and cryosphere in regulating global climate on a variety of spatial and temporal scales. A second recurring theme in this
Authors
Charles H. Greene, Andrew J. Pershing, Thomas M. Cronin, Nicole Ceci
Quaternary paleoceanography of the central Arctic based on Integrated Ocean Drilling Program Arctic Coring Expedition 302 foraminiferal assemblages
The Integrated Ocean Drilling Program (IODP) Arctic Coring Expedition (ACEX) Hole 4C from the Lomonosov Ridge in the central Arctic Ocean recovered a continuous 18 in record of Quaternary foraminifera yielding evidence for seasonally ice-free interglacials during the Matuyama, progressive development of large glacials during the mid-Pleistocene transition (MPT) ???1.2-0.9 Ma, and the onset of high
Authors
T. M. Cronin, S.A. Smith, F. Eynaud, M. O'Regan, J. King
Increased terrestrial to ocean sediment and carbon fluxes in the northern Chesapeake Bay associated with twentieth century land alteration
We calculated Chesapeake Bay (CB) sediment and carbon fluxes before and after major anthropogenic land clearance using robust monitoring, modeling and sedimentary data. Four distinct fluxes in the estuarine system were considered including (1) the flux of eroded material from the watershed to streams, (2) the flux of suspended sediment at river fall lines, (3) the burial flux in tributary sediment
Authors
C. Saenger, T. M. Cronin, D. Willard, J. Halka, R. Kerhin
Abyssal ostracods from the South and Equatorial Atlantic Ocean: Biological and paleoceanographic implications
We report the distribution of ostracods from ???5000 m depth from the Southeast and Equatorial Atlantic Ocean recovered from the uppermost 10 cm of minimally disturbed sediments taken by multiple-corer during the R/V Meteor DIVA2 expedition M63.2. Five cores yielded the following major deep-sea genera: Krithe, Henryhowella, Poseidonamicus, Legitimocythere, Pseudobosquetina, and Pennyella. All gene
Authors
Moriaki Yasuhara, T. M. Cronin, Arbizu P. Martinez
Abrupt climate change and collapse of deep-sea ecosystems
We investigated the deep-sea fossil record of benthic ostracodes during periods of rapid climate and oceanographic change over the past 20,000 years in a core from intermediate depth in the northwestern Atlantic. Results show that deep-sea benthic community "collapses" occur with faunal turnover of up to 50% during major climatically driven oceanographic changes. Species diversity as measured by t
Authors
Moriaki Yasuhara, T. M. Cronin, P.B. Demenocal, H. Okahashi, B.K. Linsley
Paleoecology and ecosystem restoration: Case studies from Chesapeake Bay and the Florida Everglades
Climate extremes that cause droughts, floods, or large temperature fluctuations can complicate ecosystem restoration efforts focused on local and regional human disturbance. Restoration targets are often based primarily on monitoring data and modeling simulations, which provide information on species' short-term response to disturbance and environmental variables. Consequently, the targets may be
Authors
Debra A. Willard, Thomas M. Cronin