Welcome to REDMAST

The Gulf of Aqaba, northern Red Sea, is recognized as a unique and easily accessible "natural marine laboratory" that provides the opportunity to study fundamental oceanographic processes in a quasi-open, deep, oligotrophic ocean environment at unprecedented spatial and temporal resolution, and subsequently, close some of the knowledge gaps related to open ocean biogeochemical processes.

The Red Sea Dust, Marine Particles and Seawater Timeseries (REDMAST) project brings together long term, highly resolved, coeval time series of dust, marine particulate matter and seawater geochemistry, whose interaction plays a critical role in the marine environment, and on wider scales, modulates global climate and the source to sink signal transfer to seafloor sediments.

REDMAST is GEOTRACES process study GIpr09. All sampling and lab work within the REDMAST project adheres to GEOTRACES work protocols.

Schematic diagram of the Gulf of Aqaba. The REDMAST project includes the operation of a sediment trap time series, dust sampling, and perform dozens of sampling cruises each year

Dust

Atmospheric dust loads and chemical compositions serve as a key link between global climate patterns and marine biogeo-chemical cycles. The primary source of atmospheric dust in the world today is the Sahara-Arabian desert belt. Although this source was also active during the Quaternary, the interpretation of paleo-dust records and their effects on marine ecosystems is complicated by the scarcely reported atmospheric load patterns of bioavailable phases (i.e., water and acid leachable phases) and present-day contamination of anthropogenic components.

This study reports a multi-annual time series of atmospheric dust loads and their chemical compositions collected in the north Gulf of Aqaba (north Red Sea) at a weekly to bi-weekly resolution. Major and trace element abundances in each sample are reported for three fractions: water- soluble salts, carbonates and oxides (weak acid leach), and Al-silicates.

Dust time series and record of precipitation (Torfstein et al., 2017)

Marine Particles

Here, we set out to study bulk and export production fluxes on a monthly- to daily- timescales at the deep oligotrophic Gulf of Aqaba, northern Red Sea, using sediment traps deployed continuously since 2014.

Particles sinking through the oceanic water column, and in particular the particulate organic carbon (POC), undergo significant changes during this process. As they gradually sink, the flux of POC is known to decrease sharply with depth due to remineralization into inorganic nutrients and dissolved organic matter. Accordingly, a central caveat in studies of past environmental changes, including the history of export production, which is the flux of POC produced in the upper ocean that escapes to deeper waters, is the linkage between the sedimentary record to that of the overlying water column, i.e., the efficiency of the water–sediment signal transfer.

Among other factors, the magnitude of export production is controlled by the availability of dissolved macro- and micro- nutrients that drive primary production, dust fluxes that not only deliver nutrients but also appear to play a role in the aggregation and subsequent sinking of particulate matter, and ocean circulation patterns. These processes are even more complex in marginal seas, where fluvial fluxes and bottom resuspension are more significant and result in episodic increases in the concentrations of particles in the water column with additional impacts on the marine environment in general, and export production in particular.

Particle fluxes in the Gulf of Aqaba (From: Torfstein et al., 2020)

Seawater

Oceanic sampling campaigns in open oceans are typically performed across long transects and provide ‘snapshots’ of the seawater composition at the time of sampling. Due to the vast distances and complexity of working in deep open ocean environments, the spatial and temporal sampling resolution of trace metal concentrations and isotopic compositions in these marine settings is typically very low. Hence, sampling across abrupt events, such as dust storms, which might impose significant variations on the seawater composition, is very difficult and rare. Thus, the impact of very short-term events (daily, weekly) on the oceanic water column is currently very poorly known and usually only studied through laboratory experiments while in-situ observations remain scarce.

Here, we sample vertical seawater profiles across dust storms, and study their dissolved trace element concentrations and isotopic compositions (Pb, Th, Ba).

Profiles of Pb concentrations (Chien et al., 2018)

Graduate student Tal Benaltabet processing seawater samples in the clean lab

Collaborators

Adina Paytan, University of California Santa Cruz

Ahuva Almogi-Labin, Geological Survey of Israel

Claudia Benitez-Nelson, University of South Carolina

Eric Achterberg, GEOMAR

Miguel Frada, Institute of Life Sciences, Hebrew University of Jerusalem

Nadya Teutch, Geological Survey of Israel

Stephanie S. Kienast, Department of Oceanography, Dalhousie University

Tristan Horner, Woods Hole Oceanographic Institute

Yeala Shaked, Institute of Earth Sciences, Hebrew University of Jerusalem

Yigal Erel, Institute of Earth Sciences, Hebrew University of Jerusalem

Yonathan Shaked, National Monitoring Program

Stephanie Kienast, Yonathan Shaked, Natalie Chernihovsky, Adi Torfstein and Barak Yarden

Dedicated to science: Tal Benaltabet and Gil Lapid getting ready to sample a rare flash flood

Related Publications

In progress

Lapid G. and Torfstein A., Uranium isotopes and trace element distributions in atmospheric dust (in preparation)

Benaltabet T., Lapid G., Alkalay R., Weinstein Y., Steffens T., Achterberg E.P. and Torfstein A., The eastern Mediterranean land to sea continuum of dissolved trace metals, rare earth elements and Pb isotopes (in review)

Published

Steiner Z., Benaltabet T. and Torfstein A. (accepted) Dynamics of marine carbon and silica: a field study of the mechanisms controlling seawater major element concentrations. Limnology & Oceanography.

Mayfield K.K., Horner T.J., Torfstein A., Auro M.E., Crockford P.W. and Paytan A. (2024) Barium cycling in the Gulf of Aqaba. Frontiers in Earth Science 12, 1178487. link

Benaltabet T., Lapid G. and Torfstein A. (2023) Response of dissolved trace metals to dust storms, sediment resuspension and flash floods in the Gulf of Aqaba, northern Red Sea. Global Biogeochemical Cycles 37, e2023GB007858. link

Levy N., Torfstein A., Schiebel R., Chernihovsky N., Jochum K.P., Weis U., Stoll B. and Haug G.H. (2023) Temperature calibration of high Mg-calcite planktic Foraminifera shells from the hypersaline Gulf of Aqaba. Geochemistry, Geophysics, Geosystems 24, e2022GC010742. pdf, link

Chernihovsky N., Torfstein A. and Almogi-Labin A. (2023) Daily timescale dynamics of planktonic foraminifera shell-size distributions. Frontiers in Marine Science 10:1126398. link

Keuter S., Koplovitz G., Torfstein A. and Frada M. (2023) Two-year seasonality (2017, 2018), export and long-term changes in coccolithophore communities in the subtropical ecosystem of the Gulf of Aqaba, Red Sea. Deep-Sea Research Part I 191, 103919. pdf, link

Kienast S.S. and Torfstein A. (2022) Evaluation of biological carbon pump metrics in the subtropical Gulf of Aqaba, northern Red Sea. Global Biogeochemical Cycles 36, e2022GB007452. pdf, link

Benaltabet T., Lapid G. and Torfstein A. (2022) Dissolved aluminum dynamics in response to dust storms, wet deposition, and sediment resuspension in the Gulf of Aqaba, northern Red Sea. Geochimica et Cosmochimica Acta 335, 137-154. pdf, link

Benaltabet T., Lapid G. and Torfstein A. (2020) Seawater Pb concentration and isotopic composition response to daily time scale dust storms in the Gulf of Aqaba, Red Sea. Marine Chemistry 227, 103895. pdf, link

Chernihovsky N., Almogi-Labin A., Kienast S.S. and Torfstein A. (2020) The daily resolved temperature dependence and structure of planktonic foraminifera blooms. Scientific Reports 10(1), 1-12. link

Torfstein A., Kienast S.S., Rivlin A., Isaacs S., Yarden B. and Shaked Y. (2020) Bulk and export production fluxes in the Gulf of Aqaba, northern Red Sea. ACS Earth and Space Chemistry 4(8), 1461-1479. pdf, link

Hartman A., Torfstein A. and Almogi-Labin A. (2020) Climate swings in the northern Red Sea over the last 150,000 years from εNd and Mg/Ca of marine sediments. Quaternary Science Reviews 231, 106205. link, pdf

Chien C-T., Benaltabet T., Torfstein A. and Paytan A. (2019) Contributions of atmospheric deposition to Pb concentration and isotopic composition in seawater and particulate matter in the Gulf of Aqaba, Red Sea. Environmental Science & Technology 53, 6162-6170. pdf

Chernihovsky N., Torfstein A. and Almogi-Labin A. (2018) Seasonal flux patterns of planktonic foraminifera in a deep, oligotrophic, marginal sea: sediment trap time series from the Gulf of Aqaba, north Red Sea. Deep-Sea Research Part I 140, 78-94. pdf

Torfstein A. and Kienast S.S. (2018) No correlation between atmospheric dust and surface chlorophyll-a in the oligotrophic Gulf of Aqaba, northern Red Sea. Journal of Geophysical Research - biogeosciences, 123, doi.org/10.1002/2017JG004063. pdf, Eos Research Spotlight, GEOTRACES highlight

Torfstein A., Teutsch N., Tirosh O., Shaked Y., Rivlin T., Zipori A., Stein M., Lazar B. and Erel Y. (2017) Chemical characterization of atmospheric dust from a weekly time series in the north Red Sea between 2006-2010. Geochimica et Cosmochimica Acta 211, 373-393. pdf, link

Talks and Meeting presentations

Benaltabet T., Lapid G. and Torfstein A. (2020) Seasonal Seawater Al Dynamics and Response to Short-Term Perturbations in the Gulf of Aqaba, Northern Red Sea, Goldschmidt meeting.

Lapid G., Benaltabet T. and Torfstein A. (2020) Dissolved 230Th and 232Th as tracers of Particle Fluxes in the Gulf of Aqaba, Red Sea, Goldschmidt meeting.

Torfstein A., Kienast S.S., Tirosh O. and Yarden B. (2020) Major and trace element settling and burial fluxes in the Gulf of Aqaba, northern Red Sea, Goldschmidt meeting. Link.

Benaltabet T. and Torfstein A. (2019) Oligotrophic seawater Pb response to daily timescale dust storms, Goldschmidt meeting.

Lapid G. and Torfstein A. (2019) Dissolved 230Th and 232Th as tracers of the impact of dust storms in the Gulf of Aqaba, Red Sea, ASLO meeting.

Chernihovsky N., Almogi-Labin A. and Torfstein A. (2019) Seasonal flux patterns of planktonic foraminifera in a deep, oligotrophic, marginal sea: sediment trap time series from the Gulf of Aqaba, northern Red Sea, IAAS meeting.

Torfstein A., Teutsch N., Tirosh O., Shaked Y., Rivlin T., Zipori A., Stein M., Lazar B. and Erel Y. (2019) Chemical Characterization of Atmospheric Dust from a Weekly Time Series in the North Red Sea between 2006-2010, 7th Kaplan Symposium.

Torfstein A., Kienast S.S., Shaked Y. and Yarden B. (2019) Bulk and export production fluxes in the Gulf of Aqaba, northern Red Sea, 7th Kaplan Symposium.

Lapid G. and Torfstein A. (2019) Dissolved 230Th and 232Th as tracers of the impact of dust storms in the Gulf of Aqaba, Red Sea, 7th Kaplan Symposium.

Benaltabet T. and Torfstein A. (2019) Dissolved trace metals and Pb isotopes across dust storm events in the oligotrophic waters of the Gulf of Aqaba, Red Sea, 7th Kaplan Symposium.

Kienast S.S., Torfstein A., Riehl L. and Fennel K. (2018) Organic carbon fluxes and Nitrogen isotopes in the oligotrophic Gulf of Aqaba, Goldschmidt meeting.

Benaltabet T. and Torfstein A. (2018) Dissolved trace metals and Pb isotopes across dust storm events in the oligotrophic waters of the Gulf of Aqaba, Goldschmidt meeting.

Torfstein A. and Kienast S.S. (2018) Trace element fluxes and export production across daily-, seasonal- and multiannual- timescales in the oligotrophic Gulf of Aqaba, Red Sea, Goldschmidt meeting.

Erel Y., Goldstein S.L., Torfstein A., Palchan D., Ben Israel M., and Stein M. (2018) Contemporary dust storms as key for understanding paleo-synoptic conditions in the Levant, 3rd International Conference on Atmospheric Dust, Italy.

Kienast S., Torfstein A. and Shaked Y. (2018) Sinking fluxes from a high-resolution sediment trap time series in the Gulf of Aqaba: Does dust input play a role for export production?, PAGES DICE workshop, Las Cruces, Chile.

Chernihovsky N., Almogi-Labin A. and Torfstein A. (2018) Seasonal flux patterns of planktonic foraminifera in a deep, oligotrophic, marginal sea: sediment trap time series from the Gulf of Aqaba, north Red Sea. Foraminifera in a changing world workshop, Edinburgh, Scotland.

Chernihovsky N., Almogi-Labin A. and Torfstein A. (2017) Living on the edge: Planktonic foraminifera biodiversity and fluxes in the Red Sea and Gulf of Aqaba, IAAS meeting.

Kienast S., Torfstein A. and Shaked Y. (2017) Fluxes and nitrogen isotopes in sediment traps in the Gulf of Aqaba, Schulich meeting, Eilat.

Teutsch N., Torfstein A., Tirosh O., Shaked Y., Rivlin T., Zipori A., Stein M., Lazar B. and Erel Y. (2017) Chemical Characterization of Atmospheric Dust from a Weekly Time Series in the North Red Sea between 2006-2010, Goldschmidt meeting.

Torfstein A., Hartman A. and Almogi-Labin A. (2017) A meridional Tracking Late Quaternary Sediment Provenance and Rain Belt Shifts Across the Red Sea from eNd and Element Abundances in Dust and Marine Cores, Goldschmidt meeting.

Torfstein A., Teutsch N., Tirosh O., Shaked Y., Rivlin T., Zipori A., Stein M., Lazar B. and Erel Y. (2017) A multi-annual time series of north Red Sea dust loads and their chemical composition: provenance, impact on marine biogeochemical cycles and implications for paleo-dust reconstructions, PAGES 5th Open Science Meeting, Zaragoza, Spain.

Torfstein A., Kienast S.S. and Shaked Y. (2016) Bulk and export production fluxes from sediment traps in the Gulf of Aqaba, north Red Sea, AGU meeting.

Chernihovsky N., Almogi-Labin A., Torfstein A. (2016) High-resolution temporal dynamics of planktonic foraminifera assemblages from sediment traps in the modern Gulf of Aqaba waters, Israel Geological Society Annual Meeting.

Torfstein A. and Steiner Z. (2016) A 470 year record of anthropogenic activity in the Gulf of Aqaba from Pb isotopes in marine sediments, Israel Geological Society Annual Meeting.

Hartman A. and Torfstein A. (2016) Gulf of Aqaba and Red Sea sediment provenance during the last 150 kyrs from major and trace element concentrations and neodymium isotopes, Israel Geological Society Annual Meeting.

Torfstein A., Kienast S., Shaked Y., Yarden B., Shalev N., Rivlin A., Isaacs S. (2016) The first deployment of sediment traps in the Gulf of Aqaba: a new time series of export production and biogeochemical cycling of marine particulates, Israel Geological Society Annual Meeting.

Chernihovsky N., Almogi-Labin A. and Torfstein A. (2016) High-resolution temporal dynamics of planktonic foraminifera assemblages from sediment traps in the modern Gulf of Aqaba waters, Batsheva de Rothschild workshop: live foraminifera as a new model system for monitoring and reconstructing marine environments.

Chernihovsky N., Almogi-Labin A. and Torfstein A. (2016) High-resolution temporal dynamics of planktonic foraminifera assemblages from sediment traps in the Gulf of Aqaba waters, IAAS meeting.

Hartman A. and Torfstein A. (2015) Terrigenous fluxes and seawater circulation in the North Red Sea since the last Interglacial from eNd and trace element concentrations, Goldschmidt meeting.

Torfstein A., Kienast S., Shaked Y., Yarden B., Shalev N. (2015) A new high resolution time series of export production in the Gulf of Aqaba, north Red Sea, Gordon Chemical Oceanography conference.

Torfstein A., Teutch N., Tirosh O., Tzipori A., Shaked Y., Stein M., Goldstein S., Erel Y. (2015) Modern and Late Quaternary atmospheric dust time-series in the Levant, Batsheva de Rothschild Seminar on Atmospheric Dust, Loess and Soils.

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