Climate Research and Development

Geologic Records of High Sea Levels

Two units (Q4 and Q5) of the Key Largo Limestone exposed in the abandoned quarry walls found in Key Largo Hammocks State Botanical Site, northern Key Largo. Hypothesized contact is exposed about a meter below the ground surface (dashed line in lower photograph). Also shown are U-series ages of Montastraea annularis from both units.
Two units (Q4 and Q5) of the Key Largo Limestone exposed in the abandoned quarry walls found in Key Largo Hammocks State Botanical Site, northern Key Largo. Hypothesized contact is exposed about a meter below the ground surface (dashed line in lower photograph). Also shown are U-series ages of Montastraea annularis from both units.

We address the question of potential future rates and magnitudes of sea level rise by examining times of higher-than-modern sea level rise in the past: the mid-Pliocene warm period ~3 Ma; the marine isotope (MIS) stage 11 interglacial period, ~400 ka; the last interglacial period, MIS 5, particularly MIS 5.5 (~125 ka); and the last-glacial-to-Holocene sea level rise from ~21 ka to the present. We document the magnitudes of past sea-level high stands by field mapping, stratigraphic measurements, and precise elevation measurements using state-of-the-art GPS techniques. Geochronology is accomplished by AMS radiocarbon dating of mollusks (for Holocene-to-last-glacial deposits), thermal ionization mass spectrometric (TIMS) uranium-series dating of corals (for last MIS 5 to MIS 11 deposits) and precise TIMS Sr-isotope measurements of mollusks (for MIS 11 to mid-Pliocene deposits). We reconstruct marine paleotemperatures during sea-level high stands by detailed paleozoogeographic interpretations of fossil mollusk assemblages, a time-tested traditional method of paleoclimatic studies in marine settings.

Why is this research important?

One of the most pressing issues in studies of climate change is the possible rise of sea level due to loss of major ice sheets, which in turn may result from global warming. It is not known which polar ice sheets (Greenland, West Antarctic, East Antarctic) are most at risk for mass loss that could contribute to sea level rise. Furthermore, it is not known what the possible magnitude of sea level rise is under interglacial climate conditions, how rapidly sea level may rise, or how long high sea levels may be retained. All these questions have been posed as major uncertainties in the second-order draft of the IPCC 2012 report, Chapter 5, section 5.6. The goals of this project are to shed light on these questions by studying warm climate analogs of the geologic past.

Project Lead:
Dan Muhs
Project Team:
Aleinikoff, John N., Budahn, James R., Muhs, Daniel R., Ohms, Mark S., Pigati, Jeff, Schumann, R. Randall, Simmons, Kathleen R., Skipp, Gary, Zellman, Kristine
Project Website

29 publications matching the specified parameters were found.

Muhs, D.R., Budahn, J.R., Skipp, G.L., and McGeehin, J.P., 2016, Geochemical evidence for seasonal controls on the transportation of Holocene loess, Matanuska Valley, southern Alaska, USA: Aeolian Research, v. 21, p. 61-73.
Available at: http://dx.doi.org/10.1016/j.aeolia.2016.02.005

Pigati, J.S., Muhs, D.R. and McGeehin, J.P., 2016, On the importance of stratigraphic control for vertebrate fossil sites in Channel Islands National Park, California, USA: Examples from new Mammuthus finds on San Miguel Island, Quaternary International.
Available at: https://doi.org/10.1016/j.quaint.2016.07.015

Muhs, D.R., Simmons, K.R., Groves, L.T., McGeehin, J.P., Schumann, R.R., and Agenbroad, L.D., 2015, Late Quaternary sea-level history and the antiquity of mammoths (Mammuthus exilis and Mammuthus columbi), Channel Islands National Park, California, USA: Quaternary Research, v. 83, p. 502-521.
Available at: http://dx.doi.org/10.1016/j.yqres.2015.03.001

Pigati, J.S., McGeehin, J.P., Muhs, D.R., Grimley, D.C., Nekola, J.C., 2015, Radiocarbon dating loess deposits in the Mississippi Valley using terrestrial gastropod shells (Polygyridae, Helicinidae, Discidae): Aeolian Research, v. 16, p. 25-33.
Available at: http://dx.doi.org/10.1016/j.aeolia.2014.10.005

Reeder-Myers, L., Erlandson, J.M., Muhs, D.R., Rick, T.C., 2015, Sea level, paleogeography, and archeology on California's Northern Channel Islands: Quaternary Research, v. 83, p. 263-272.
Available at: http://dx.doi.org/10.1016/j.yqres.2015.01.002

Muhs, D.R., 2014, The contributions of Donald Lee Johnson to understanding the Quaternary geologic and biogeographic history of the California Channel Islands: Monographs of the Western North American Naturalist, v. 7, p. 1-20.

Muhs, D.R., Cattle, S.R., Crouvi, O., Rousseau, D.D., Sun, J., Zarate, M.A., 2014, Loess Records, in Knippertz, P. and Stuut, J.B.W., eds., Mineral Dust: A Key Player in the Earth System, The Netherlands, Springer Science + Business Media, p. 411- 441.

Muhs, D.R., Groves, L.T., and Schumann, R.R., 2014, Interpreting the paleozoogeography and sea level history of thermally anomalous marine terrace faunas: a case study from the Last Interglacial Complex of San Clemente Island, California: Monographs of the Western North American Naturalist, v. 7, p. 82-108.

Muhs, D.R., Meco, J., and Simmons, K.R., 2014, Uranium-series ages of corals, sea level history, and palaeozoogeography, Canary Islands, Spain: An exploratory study for two Quaternary interglacial periods: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 394, p. 99-118.

Muhs, D.R., Prins, M.A., Machalett, B., 2014, Loess as a Quaternary paleoenvironmental indicator: Past Global Changes Magazine, v. 22, p. 84-85.

Muhs, D.R., Prospero, J.M., Baddock, M.C., and Gill, T.E., 2014, The Netherlands, Springer, p. 51-74.

Muhs, D.R., Simmons, K.R., Schumann, R.R., Groves, L.T., DeVogel, S.B., Minor, S.A., and Laurel, D., 2014, Coastal tectonics on the eastern margin of the Pacific Rim: Late Quaternary sea-level history and uplift rates, Channel Islands National Park, California, USA: Quaternary Science Reviews, v. 105, p. 209-238.

Pigati, J.S., McGeehin, J.P., Skipp, G.L., and Muhs, D.R., 2014, Evidence of repeated wildfires prior to human occupation on San Nicolas Island, California: Monographs of the Western North American Naturalist, v. 7, p. 35-47.

Rick, T.C., Sillett, T.S., Ghalambor, C.K., Hofman, C.A., Ralls, K., Anderson, R.S., Boser, C.L., Braje, T.J., Cayan, D.R., and Chesser, R.T., 2014, Ecological Change on California's Channel Islands from the Pleistocene to the Anthropocene: BioScience, p. 1-13.

Schumann, R.R., Minor, S.A., Muhs, D.R., and Pigati, J.S., 2014, Landscapes of Santa Rosa Island, Channel Islands National Park, California: Monographs of the Western North American Naturalist, v. 7, p. 48-67.

Sherman, C.E., Fletcher, C.H., Rubin, K.H., Simmons, K.R., and Adey, W.H., 2014, Quaternary Research, v. 81, no. 1, p. 138-150.

Erlandson, J.M., Thomas-Barnett, L., Vellanoweth, R.L., Schwartz, S.J., Muhs, D.R., 2013, From the Island of the Blue Dolphins: A unique nineteenth-century cache feature from San Nicolas Island, California: Journal of Island and Coastal Archaeology, v. 8, p. 66-78.

Muhs, D. R., 2013, Loess and its geomorphic, stratigraphic, and paleoclimatic significance in the Quaternary. Treatise on Geomorphology. Academic Press, San Diego, CA. p. 14.

Muhs, D.R., 2013, The geologic records of dust in the Quaternary: Aeolian Research, v. 9, p. 3-48.

Muhs, D.R., Bettis, E.A. III, Roberts, H.M., Harlan, S., Paces, J.B., Reynolds, R., 2013, Chronology and provenance of last-glacial (Peoria) loess in western Iowa and paleoclimatic implications: Quaternary Research, v. 80, p. 468-481.

Muhs, D.R., Budahn, J.R., McGeehin, J.P., Bettis, E.A. III, Skipp, G., Paces, J.B., Wheeler, E.A., 2013, Loess origin, transport, and deposition over the past 10,000 years, Wrangell-St. Elias National Park, Alaska: Aeolian Research, v. 11, p. 85-99.

Muhs, D.R., Roskin, J., Tsoar, H., Skipp, G., Budahn, J.R., Sneh, A., Porat, N., Stanley, J.-D., Katra, I., Blumberg, D.G., 2013, Origin of the Sinai-Negev erg, Egypt and Israel: mineralogical and geochemical evidence for the importance of the Nile and sea level history: Quaternary Science Reviews, v. 69, p. 28-48.

Bridges, N.T., and Muhs, D.R., 2012, Duststones on Mars: Source, transport, deposition, and erosion, In: Grotzinger, J., and Milliken, R., eds., Sedimentary Geology of Mars, SEPM Special Publication No. 102, p. 169-182.

Muhs, D.R., Budahn, J.R., Prospero, J.M., Skipp, G., and Herwitz, S., 2012, Soil genesis on the island of Bermuda in the Quaternary: The importance of African dust transport and deposition: Journal of Geophysical Research (Earth Surface), v. 117, F03025.
Available at: http://dx.doi.org/10.1029/2012JF002366

Muhs, D.R., Pandolfi, J.M., Simmons, K.R., and Schumann, R.R., 2012, Sea-level history of past interglacial periods from uranium-series dating of corals, Curacao, Leeward Antilles islands: Quaternary Research, v. 78, p. 157-169.

Muhs, D.R., Simmons, K.R., Schumann, R.R., Groves, L.T., Mitrovica, J.X., and Laurel, D., 2012, Sea-level history during the last interglacial complex on San Nicolas Island, California: Implications for glacial isostatic adjustment processes, paleozoogeography and tectonics: Quaternary Science Reviews, v. 37, p. 1-25.

Schumann, R.R., Minor, S.A., Muhs, D.R., Groves, L.T., and McGeehin, J.P., 2012, Tectonic influences on the preservation of marine terraces: Old and new evidence from Santa Catalina Island, California: Geomorphology, v. 179, p. 208-224.

Meco, J., Muhs, D.R., Fontugne, M., Ramos, A.J., Lomoschitz, A., and Patterson, D., 2011, Late Pliocene and Quaternary Eurasian locust infestations in the Canary Archipelago: Lethaia, v. 44, no. 4, p. 440-454.

Muhs, D.R., Simmons, K.R., Schumann, R.R., and Halley, R.B., 2011, Sea-level history of the past two interglacial periods: new evidence from U-series dating of reef corals from south Florida: Quaternary Science Reviews, v. 30, no. 5, p. 570-590.

Impacts of Climate Change on Coastal and Eolian Landscapes

The project studies the geologic records of climate change in eolian (windblown) deposits of the U.S, evaluates the importance of eolian additions to soils, and assesses the potential for renewed activity of wind-blown sediments. In addition, it will investigate the potential effects windblown sediments have on climate itself, through radiative transfer and fertilization of primary producers in the ocean.

This project also researches past sea level high stands (during warm interglacial periods) as analogs for future sea level rise.

Why is this research important?

Eolian deposits are some of our most important records of global climate change. In addition, the finest-grained eolian materials (long-range-transported dust) have important influences on climate itself.

Study of sea levels during past interglacial periods of give us clues as to how large ice sheets responded to warm periods. This in turn can tell us much about how large ice sheets of the present (Greenland, Antarctica) may respond to future warming and how high sea level might rise in the future.