John Barron, Ph.D.
John is a Scientist Emeritus with the Geology, Minerals, Energy, and Geophysics Science center in Menlo Park, CA.
John is a marine micropaleontologist (diatoms) with expertise in and biostratigraphy and paleoceanography. His biostratigraphic expertise extends from the Late Cretaceous to the Holocene, with an emphasis on the North Pacific, eastern equatorial Pacific, and Southern Ocean. John's paleoclimate expertise is mostly on the Holocene of the North Pacific, ranging from the Gulf of California to the Gulf of Alaska. As an Emeritus Research Geologist, his research is directed toward developing and comparing Holocene sea surface temperature records in these eastern North Pacific regions with hydroclimate records in western North America and suggesting links.
Professional Experience
2012- 2016 (June) - Project Chief, Pacific Ocean Climate Variability: Effects on North American Precipitation Patterns Project, Climate and Land Use Change, Research & Development Program
1995-1997 – Project Chief: Pliocene, Research, Interpretation, and Synoptic Mapping(PRISM), Global Change & Climate History Program, Volcano Hazards Team, Menlo Park
1984-1995 – Project Chief and micropaleontologist of various USGS biochronology projects providing support to USGS mapping projects, Paleontology & Stratigraphy Branch
1974-1983 –Micropaleontolgist (diatoms), Paleontology & Stratigraphy Branch
Scientific Cruise Experience
Deep Sea Drilling Project (Leg 57-Japan; 63 (California margin; 85 (eastern equatorial Pacific); micropaleontologist
Ocean Drilling Project 119 (Antarctic margin, Indian Ocean; Co-Chief Scientist), 145 (North Pacific transect, micropaleotologist).
Education and Certifications
1969 BS (Geology), University of California, Los Angeles
1974 PhD (Geology), University of California, Los Angeles
Honors and Awards
2011 - The Brady Medal of the Micropalaeological Society (UK)
1994 - U.S. Dept. of Interior Meritorious Service Award
1986 - Charles Schuchert Award - from the Paleontological Society for excellence and promise in paleontology for scientists under 40 years old
Science and Products
Lake oxygen isotopes as recorders of North American Rocky Mountain hydroclimate: Holocene patterns and variability at multi-decadal to millennial time scales
Vegetation response to southern California drought during the Medieval Climate Anomaly and early Little Ice Age (AD 800–1600)
The Holocene history of the North American Monsoon: 'known knowns' and 'known unknowns' in understanding its spatial and temporal complexity
Paleoceanographic, and paleoclimatic constraints on the global Eocene diatom and silicoflagellate record
What caused terrestrial dust loading and climate downturns between A.D. 533 and 540?
Diatom and silicoflagellate biostratigraphy for the late Eocene: ODP 1090 (sub-Antarctic Atlantic)
High-resolution paleoclimatology of the Santa Barbara Basin during the Medieval Climate Anomaly and early Little Ice Age based on diatom and silicoflagellate assemblages in Kasten core SPR0901-02KC
Cenozoic planktonic marine diatom diversity and correlation to climate change
Response of diatom and silicoflagellate assemblages in the central Gulf of California to regional climate change during the past 55 kyrs
Response of diatoms and silicoflagellates to climate change in the Santa Barbara Basin during the past 250 years and the rise of the toxic diatom Pseudo-nitzschia australis
Refinement of late-Early and Middle Miocene diatom biostratigraphy for the east coast of the United States
Chronology of Eocene-Miocene sequences on the New Jersey shallow shelf: implications for regional, interregional, and global correlations
Science and Products
- Science
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Filter Total Items: 114
Lake oxygen isotopes as recorders of North American Rocky Mountain hydroclimate: Holocene patterns and variability at multi-decadal to millennial time scales
Lake sediment oxygen isotope records (calcium carbonate-δ18O) in the western North American Cordillera developed during the past decade provide substantial evidence of Pacific ocean–atmosphere forcing of hydroclimatic variability during the Holocene. Here we present an overview of 18 lake sediment δ18O records along with a new compilation of lake water δ18O and δ2H that are used to characterize laAuthorsLesleigh Anderson, Max Berkelhammer, John A. Barron, Byron A. Steinman, Bruce P. Finney, Mark B. AbbottVegetation response to southern California drought during the Medieval Climate Anomaly and early Little Ice Age (AD 800–1600)
High-resolution studies of pollen in laminated sediments deposited in Santa Barbara Basin (SBB) core SPR0901-02KC reflect decadal-scale fluctuations in precipitation spanning the interval from AD 800–1600. From AD 800–1090 during the Medieval Climate Anomaly (MCA) SBB sediments were dominated by xeric vegetation types (drought-resistant coastal sagebrush and chaparral) implying reduced precipitatiAuthorsLinda E. Heusser, Ingrid L. Hendy, John A. BarronThe Holocene history of the North American Monsoon: 'known knowns' and 'known unknowns' in understanding its spatial and temporal complexity
Evidence for climatic change across the North American Monsoon (NAM) and adjacent areas is reviewed, drawing on continental and marine records and the application of climate models. Patterns of change at 12,000, 9000, 6000 and 4000 cal yr BP are presented to capture the nature of change from the Younger Dryas (YD) and through the mid-Holocene. At the YD, conditions were cooler overall, wetter in tAuthorsSarah E. Metcalfe, John A. Barron, Sarah J. DaviesPaleoceanographic, and paleoclimatic constraints on the global Eocene diatom and silicoflagellate record
Eocene diatom and silicoflagellate biostratigraphy are summarized and correlated with the most recent geologic time scale as well as with the global oxygen isotope and eustatic sea level curves. The global distribution of Eocene diatom/silicoflagellate-bearing sediments varies considerably, reflecting changing oceanic gateways and paleoceanography with changing patterns that are punctuated by fourAuthorsJohn A. Barron, Catherine E. Stickley, David BukryWhat caused terrestrial dust loading and climate downturns between A.D. 533 and 540?
Sn-rich particles, Ni-rich particles, and cosmic spherules are found together at four discrete stratigraphic levels within the 362-360 m depth interval of the Greenland Ice Sheet Project 2 (GISP2) ice core (72.6°N, 38.5°W, elevation: 3203 m). Using a previously derived calendar-year time scale, these particles span a time of increased dust loading of Earth's atmosphere between A.D. 533 and 540. ThAuthorsDallas H. Abbott, Dee Breger, Pierre E. Biscaye, John A. Barron, Robert A. Juhl, Patrick McCaffertyDiatom and silicoflagellate biostratigraphy for the late Eocene: ODP 1090 (sub-Antarctic Atlantic)
Abundant and well-preserved diatoms and silicofl agellate assemblages are documented through a complete late Eocene sequence, ODP Hole 1090B, recovered from the southern Agulhas Ridge in the sub-Antarctic South Atlantic. A sequence of Cestodiscus (diatom) species occurrence events involving C. pulchellus var. novazealandica, C. fennerae, C. antarcticus, C. convexus, C. trochus, and C. robustus isAuthorsJohn A. Barron, David B. Bukry, Rainer GersondeHigh-resolution paleoclimatology of the Santa Barbara Basin during the Medieval Climate Anomaly and early Little Ice Age based on diatom and silicoflagellate assemblages in Kasten core SPR0901-02KC
Diatom and silicoflagellate assemblages documented in a high-resolution time series spanning 800 to 1600 AD in varved sediment recovered in Kasten core SPR0901-02KC (34°16.845’ N, 120°02.332’ W, water depth 588 m) from the Santa Barbara Basin (SBB) reveal that SBB surface water conditions during the Medieval Climate Anomaly (MCA) and the early part of the Little Ice Age (LIA) were not extreme by mAuthorsJohn A. Barron, David B. Bukry, Ingrid L. HendyCenozoic planktonic marine diatom diversity and correlation to climate change
Marine planktonic diatoms export carbon to the deep ocean, playing a key role in the global carbon cycle. Although commonly thought to have diversified over the Cenozoic as global oceans cooled, only two conflicting quantitative reconstructions exist, both from the Neptune deep-sea microfossil occurrences database. Total diversity shows Cenozoic increase but is sample size biased; conventional subAuthorsDavid Lazarus, John Barron, Johan Renaudie, Patrick Diver, Andreas TürkeResponse of diatom and silicoflagellate assemblages in the central Gulf of California to regional climate change during the past 55 kyrs
High-resolution studies of diatoms and silicoflagellates of the past 55 kyrs in cores MD02-2517/2515 from the central Gulf of California (GoC) reveal profound changes in GoC surface waters. Roperia tesselata, a diatom proxy for late winter–early spring upwelling, and Dictyocha stapedia, a subtropical silicoflagellate indicative of GoC sea surface temperatures (SSTs) > 24 °C, are common during theAuthorsJohn A. Barron, David Bukry, Heather CheshireResponse of diatoms and silicoflagellates to climate change in the Santa Barbara Basin during the past 250 years and the rise of the toxic diatom Pseudo-nitzschia australis
Diatoms and silicoflagellate assemblages were examined in two year-increments of varved samples spanning the interval from 1748 through 2007 in Santa Barbara Basin (SBB) box core SBBC0806 to determine the timing and impact of possible 20th century warming on several different components of the plankton. Diatoms (Thalassionema nitzschioides =TN) and silicoflagellates (Distephanus speculum s.l. =DS)AuthorsJohn A. Barron, David Bukry, David B. Field, Bruce FinneyRefinement of late-Early and Middle Miocene diatom biostratigraphy for the east coast of the United States
Integrated Ocean Drilling Program (IODP) Expedition 313 continuously cored Lower to Middle Miocene sequences at three continental shelf sites off New Jersey, USA. The most seaward of these, Site M29, contains a well-preserved Early and Middle Miocene succession of planktonic diatoms that have been independently correlated with the geomagnetic polarity time scale derived in studies from the equatorAuthorsJohn A. Barron, James Browning, Peter Sugarman, Kenneth G. MillerChronology of Eocene-Miocene sequences on the New Jersey shallow shelf: implications for regional, interregional, and global correlations
Integrated Ocean Drilling Program Expedition 313 continuously cored and logged latest Eocene to early-middle Miocene sequences at three sites (M27, M28, and M29) on the inner-middle continental shelf offshore New Jersey, providing an opportunity to evaluate the ages, global correlations, and significance of sequence boundaries. We provide a chronology for these sequences using integrated strontiumAuthorsJames V. Browning, Kenneth G. Miller, Peter J. Sugarman, John Barron, Francine M.G. McCarthy, Denise K. Kulhanek, Miriam E. Katz, Mark D. Feigenson - News