Harry is a Research Geologist specializing in micropaleontology as well as Project Chief of Geological Investigations of the Neogene and PRISM Projects. His research provides crucial information on how the Earth responds to changing conditions for citizens and policy-makers. Harry is an expert in paleontology, environmental reconstruction, stratigraphic correlation and climate change.
Harry is a Research Geologist specializing in micropaleontology as well as Project Chief of Geological Investigations of the Neogene and PRISM Projects. His research provides crucial information on how the Earth responds to changing conditions for citizens and policy-makers. Harry is an expert in paleontology, environmental reconstruction, stratigraphic correlation and climate change.
Dr. Dowsett's current research, Geological Investigations of the Neogene, is at the nexus of global scale geological data analysis and paleoclimate modeling, with special emphasis on environmental and ecological changes accompanying climate change along the eastern United States.
He is Co-Lead of the international Pliocene Model Intercomparison Project (PlioMIP). PlioMIP is an international climate modelling initiative to study and understand climate and environments of the Late Pliocene, and their potential relevance in the context of future climate change. PlioMIP operates under the umbrella of the Palaeoclimate Modelling Intercomparison Project (PMIP), which examines multiple intervals in Earth history, the consistency of model predictions in simulating these intervals, and their ability to reproduce geological climate archives. PlioMIP currently involves 20 research institutions.
Dr. Dowsett leads the international PRISM effort which focuses on the most recent period in geologic history bearing a resemblance to environmental projections for the 21st century. Through better understanding of past, present and future change, PRISM provides products designed to assist in:
- Predicting the strength and frequency of El Nino events and the related risks of droughts and floods
- Defining the bathymetric causes of Arctic sea ice variability for national security studies
- Understanding the nature of upwelling and the effects on coastal and fishing industries
- Reconstructing vegetation patterns to inform farming practices and legislation
- Predicting potential sea level rise and the risk to population centers
- Tracking storms and predicting the hydrological impact of modified atmospheric and oceanic energy transport systems
- Identifying climate model biases and testing the accuracy of future climate models.
Science and Products
Geological Investigations of the Neogene
Pliocene Research, Interpretation and Synoptic Mapping (PRISM4)
Geological Investigations of the Neogene Project
PlioMIP (Pliocene Model Intercomparison Project) Strategy, Communications and Synthesis for the IPCC Fifth Assessment Report (IPCC AR5)
Alkenone temperature estimates from the Miocene (Burdigalian, Langhian, Tortonian) and Pliocene (Zanclean) Atlantic Coastal Plain sediments
PRISM4 (mid-Piacenzian) Paleoenvironmental Reconstruction Data
Planktonic foraminifer census data from type section of Yorktown Formation at Rushmere, Virginia, USA
PRISM3 Pliocene Global Sea Surface Temperature Reconstruction
Alkenone and foraminifer abundance data from Miocene and Pliocene Atlantic Coastal Plain sediments
Community sourced mid-Piacenzian sea surface temperature (SST) data
PRISM late Pliocene (Piacenzian) alkenone - derived SST data
Planktic foraminifera
The relative stability of planktic foraminifer thermal preferences over the past 3 million years
Using paleoecological data to inform decision making: A deep-time perspective
Past terrestrial hydroclimate sensitivity controlled by Earth system feedbacks
The Yorktown Formation: Improved stratigraphy, chronology and paleoclimate interpretations from the U.S. mid-Atlantic Coastal Plain
PlioMIP: The Pliocene Model Intercomparison Project
Microfossils from Calvert Cliffs give us clues to the future warmer climate
Miocene neritic benthic foraminiferal community dynamics, Calvert Cliffs, Maryland, USA: Species pool, patterns and processes
Estimating Piacenzian sea surface temperature using an alkenone-calibrated transfer function
Biogeography and ecology of Ostracoda in the U.S. northern Bering, Chukchi, and Beaufort Seas
Evaluation of Arctic warming in mid-Pliocene climate simulations
Science and Products
- Science
Geological Investigations of the Neogene
More than a third of the United States population lives in counties directly on the shoreline, making them vulnerable to hazards associated with changing sea level and storm surges associated with hurricanes and severe storms. The geologic record contains many examples of past intervals of warm climate and high sea level. "Geological Investigation of the Neogene" is examining proxy records of...Pliocene Research, Interpretation and Synoptic Mapping (PRISM4)
PRISM will help distinguish the USGS as a world leader in paleoclimate research, data generation and delivery for use in addressing the modern world's climate-related needs. We will be recognized for the passion of our researchers and partners in providing quality, innovative paleoclimate interpretation and data analysis to the science (climate change) community and to the public we serve.Geological Investigations of the Neogene Project
Geological Investigations of the Neogene explores past warmer-than-modern climates of the mid-Miocene (about 14-17 million years ago) and Piacenzian (about 3 million years ago) to assess the potential environmental and economic impacts to population centers along the US Atlantic coast under different rates and magnitudes of changes related to warmer temperatures. Specifically, we look at past...PlioMIP (Pliocene Model Intercomparison Project) Strategy, Communications and Synthesis for the IPCC Fifth Assessment Report (IPCC AR5)
USGS PRISM (Pliocene Research, Interpretation and Synoptic Mapping) Project global data sets of Pliocene conditions, which form the most comprehensive global reconstruction for any warm period prior to the recent past, are used to drive numerical climate model simulations designed to explore the impact of climate forcings and feedbacks during the Pliocene. The Pliocene world provides an unequaled - Data
Alkenone temperature estimates from the Miocene (Burdigalian, Langhian, Tortonian) and Pliocene (Zanclean) Atlantic Coastal Plain sediments
This dataset collects sea surface temperature data generated through alkenone analysis of Neogene sediments collected from cores and outcrops of the Virginia and Maryland Atlantic Coastal Plain.PRISM4 (mid-Piacenzian) Paleoenvironmental Reconstruction Data
The mid-Piacenzian is known as a period of relative warmth when compared to the present day. A comprehensive understanding of conditions during the Piacenzian serves as both a conceptual model and a source for boundary conditions as well as means of verification of global climate model experiments. These data are provided as digital representations of mid Pliocene boundary conditions stored in NetPlanktonic foraminifer census data from type section of Yorktown Formation at Rushmere, Virginia, USA
Data consist of census counts of Pliocene planktonic foraminifera from the lectostratotype of the Yorktown Formation at Rushmere Virginia, Rice's Pit, Yorktown, and the type section of the Morgarts Beach Member at Morgarts Beach, Virginia. In total, counts of individuals from 12 samples and 25 species are included.PRISM3 Pliocene Global Sea Surface Temperature Reconstruction
PRISM3D uses multiple proxies to develop February and August synoptic reconstructions of the surface ocean. Planktonic foraminiferal assemblages were translated to February and August surface temperatures via factor analytic transfer function and the modern analog technique. Mg/Ca and alkenone paleothermometry were incorporated as supplementary data for the first time in a PRISM reconstruction. InAlkenone and foraminifer abundance data from Miocene and Pliocene Atlantic Coastal Plain sediments
Alkenone data were extracted from core and outcrop samples from the Miocene and Pliocene of the mid Atlantic Coastal Plain. The Uk'37 index is used to estimate temperature and total C37 is used to estimate productivity. Planktonic foraminifer abundance's are provided for two cores.Community sourced mid-Piacenzian sea surface temperature (SST) data
This data set collects, from peer-reviewed research, values of sea surface temperature (SST) that occurred at various sites across the Earth during a brief period of the mid-PiacenzianPRISM late Pliocene (Piacenzian) alkenone - derived SST data
This dataset collects sea surface temperature data generated through alkenone analysis of late Pliocene sediments collected from cores and field localities by USGS PRISM project members. Alkenone analysis of sample material was performed by Timothy Herbert at Brown University. - Publications
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Planktic foraminifera
Planktic foraminifera are single-celled marine organisms that secrete calcium carbonate tests. They live in the ocean's photic zone, and when they die, their tests, each about the size of a grain of sand, collect on the ocean floor. The geographic distribution of planktic foraminifera is mostly governed by the temperature and salinity of the ocean surface, and species assemblages are generally arrAuthorsHarry J. Dowsett, Marci M. RobinsonThe relative stability of planktic foraminifer thermal preferences over the past 3 million years
Stationarity of species’ ecological tolerances is a first-order assumption of paleoenvironmental reconstruction based upon analog methods. To test this and other assumptions used in quantitative analysis of foraminiferal faunas for paleoceanographic reconstruction, we analyzed paired alkenone unsaturation ratio (UK′37) 37′) sea surface temperature (SST) estimates and relative abundances of planktAuthorsHarry J. Dowsett, Marci M. Robinson, Kevin M. Foley, Timothy D. Herbert, Steve Hunter, Carin Andersson, Whittney SpiveyUsing paleoecological data to inform decision making: A deep-time perspective
Latest climate models project conditions for the end of this century that are generally outside of the human experience. These future conditions affect the resilience and sustainability of ecosystems, alter biogeographic zones, and impact biodiversity. Deep-time records of paleoclimate provide insight into the climate system over millions of years and provide examples of conditions very differentAuthorsHarry J. Dowsett, Peter Jacobs, Kim de MutsertPast terrestrial hydroclimate sensitivity controlled by Earth system feedbacks
Despite tectonic conditions and atmospheric CO2 levels (pCO2) similar to those of present-day, geological reconstructions from the mid-Pliocene (3.3-3.0 Ma) document high lake levels in the Sahel and mesic conditions in subtropical Eurasia, suggesting drastic reorganizations of subtropical terrestrial hydroclimate during this interval. Here, using a compilation of proxy data and multi-model paleocAuthorsR. Feng, T. Bhattacharya, B. Otto-Bliesner, E. Brady, A. M. Haywood, J. Tindall, S. J. Hunter, A. Abe- Ouchi, W.-L. Chan, M. Kageyama, C. Contoux, C. Guo, X. Li, G. Lohmann, C. Stepanek, N. Tan, Q. Zhang, Z. Zhang, Z. Han, J.R. Williams, D. J. Lunt, Harry J. Dowsett, Deepak Chandan, W. Richard PeltierThe Yorktown Formation: Improved stratigraphy, chronology and paleoclimate interpretations from the U.S. mid-Atlantic Coastal Plain
The Yorktown Formation records paleoclimate conditions along the mid-Atlantic Coastal Plain during the mid-Piacenzian Warm Period (3.264 to 3.025 Ma), a climate interval of the Pliocene in some ways analogous to near future climate projections. To gain insight into potential near future changes, we investigated Yorktown Formation outcrops and cores in southeastern Virginia, refining the stratigrapAuthorsHarry J. Dowsett, Marci M. Robinson, Kevin M. Foley, Timothy D. HerbertPlioMIP: The Pliocene Model Intercomparison Project
PlioMIP is a network of paleoclimate modelers and geoscientists who, through the study of the mid-Pliocene Warm Period (mPWP ~3.3–3.0 million years ago), seek to understand the sensitivity of the climate system to forcings and examine how well models reproduce past climate change.AuthorsA. M. Haywood, Harry J. DowsettMicrofossils from Calvert Cliffs give us clues to the future warmer climate
No abstract available.AuthorsSeth R Sutton, Marci M. Robinson, Stephen J. Culver, David J. Mallinson, Martin A Buzas, Harry J. DowsettMiocene neritic benthic foraminiferal community dynamics, Calvert Cliffs, Maryland, USA: Species pool, patterns and processes
The presence/absence and abundance of benthic foraminifera in successive discrete beds (Shattuck “zones”) of the Miocene Calvert and Choptank formations, exposed at the Calvert Cliffs, Maryland, USA, allows for investigation of community dynamics over space and time. The stratigraphic distribution of benthic foraminifera is documented and interpreted in the context of sea-level change, sequence stAuthorsStephen J. Culver, Seth R Sutton, David J. Mallinson, Martin A Buzas, Marci M. Robinson, Harry J. DowsettEstimating Piacenzian sea surface temperature using an alkenone-calibrated transfer function
Stationarity of environmental preferences is a primary assumption required for any paleoenvironmental reconstruction using fossil materials based upon calibration to modern organisms. Confidence in this assumption decreases the further back in time one goes, and the validity of the assumption that species temperature tolerances have not changed over time has been challenged in Pliocene studies. WeAuthorsHarry J. Dowsett, Marci M. Robinson, Kevin M. FoleyBiogeography and ecology of Ostracoda in the U.S. northern Bering, Chukchi, and Beaufort Seas
Ostracoda (bivalved Crustacea) comprise a significant part of the benthic meiofauna in the Pacific-Arctic region, including more than 50 species, many with identifiable ecological tolerances. These species hold potential as useful indicators of past and future ecosystem changes. In this study, we examined benthic ostracodes from nearly 300 surface sediment samples, >34,000 specimens, from three reAuthorsLaura Gemery, Thomas M. Cronin, Lee W. Cooper, Harry J. Dowsett, Jacqueline M. GrebmeierEvaluation of Arctic warming in mid-Pliocene climate simulations
Palaeoclimate simulations improve our understanding of the climate, inform us about the performance of climate models in a different climate scenario, and help to identify robust features of the climate system. Here, we analyse Arctic warming in an ensemble of 16 simulations of the mid-Pliocene Warm Period (mPWP), derived from the Pliocene Model Intercomparison Project Phase 2 (PlioMIP2).The PlioMAuthorsWesley de Nooijer, Qiong Zhang, Qiang Li, Qiang Zhang, Xiangyu Li, Zhongshi Zhang, Chuncheng Guo, Kerim H Nisancioglu, Alan M Haywood, Julia C. Tindall, Harry J. Dowsett, Christian Stepanek, Gerrit Lohman, Bette L. Otto-Bliesner, Ran Feng, Linda E Sohl, Mark Chandler, Ning Tan, Camille Contoux, Gilles Ramstein, Michiel Baatsen, Anna S von der Heydt, Deepak Chandan, W. Richard Peltier, A. Abe-Ouchi, W-L Chan, Youichi Kamae, Chris M Brierley