Late miocene and early pliocene palaeoceanography at the eastern equatorial Pacific IODP Site U1338: implications for climate evolution and stability

The short-term background climate variability during the climatically stable latest Miocene to early Pliocene (LM-EP) is not well understood, owing to the lack of continuous, high-resolution climate records. Assessing variability during an interval of long-term climatic stability will constrain how sensitivity of major Earth’s system components (Earth system response - ESR) to external radiative forcing has changed through time. This study investigated LM-EP climate, focussing on changes in ESR, El-Nino-Southern-Oscillation state, glacio-eustacy and the Messinian Salinity Crisis (MSC), and the origin of the Late Miocene Carbon Isotope Shift (LMCIS). This project produced the first high-resolution benthic foraminiferal δ18O and δ13C record in the eastern equatorial Pacific (IODP Site U1338) from 8.0-3.5 Ma that resolves all Milankovitch cyclicities. A high-resolution, orbitally-based age model, planktic foraminiferal δ18O, δ13C and Mg/Ca, coccolith-rich ‘clumped isotopes’ Δ47, spectral analyses and multi-site benthic foraminiferal isotope compilations were also produced. Planktic foraminiferal Mg/Ca sea surface temperatures (SSTs) were ~25 °C. Coccolith-rich Δ47 temperatures were unrealistically cold at ~10-15 °C, reflecting moderate coccolith preservation and vital effects that cause higher Δ47. Site U1338 and 982 combined benthic foraminiferal (δ18O; δ13C) wavelet analyses show moderate ESR from 6.3–4.7 Ma and after 3.7 Ma, but lower ERS from 7.0–6.3 Ma. The δ18O-minimum stage ~5.33 Ma, during long-term minimum δ18O, suggests that glacio-eustacy played a role in the MSC termination. The benthic foraminiferal δ13C compilation confirms that the LMCIS was globally synchronous and caused by a negative shift in oceanic reservoir δ13C, driven by changes in the continental carbon flux (increased sea-floor-spreading / C4-grass expansion). Data syntheses show that global warmth, dominant El-Nino state, high cryosphere sensitivity, lower ice volume and short-term ice sheet variations characterised the LM-EP pre-7.0 and post-5.7 Ma. Stable conditions occurred ~7.0-5.7 Ma, with dominant La-Nina, higher ice volume, low cryosphere sensitivity and lower SSTs.Open Acces

Data report: late Miocene to early Pliocene coccolithophore and foraminiferal preservation at Site U1338 from scanning electron microscopy

The late Miocene to early Pliocene carbonate-rich sediments recovered at Integrated Ocean Drilling Program (IODP) Site U1338 during the Expedition 320/321 Pacific Equatorial Age Transect (PEAT) program contain abundant calcareous nanno- and microfossils. Geochemical proxies from benthic and planktonic foraminiferal and coccolithophore calcite could be very useful at this location; however, good preservation of the calcite is crucial for the proxies to be robust. Here, we evaluate the preservation of specific benthic and planktonic foraminifer species and coccolithophores in fine fraction sediment at Site U1338 using backscattered electron (topography mode) scanning electron microscopy (BSE-TOPO SEM). Both investigated foraminiferal species, Cibicidoides mundulus and Globigerinoides sacculifer, have undergone some alteration. The C. mundulus show minor evidence for dissolution, and only some specimens show evidence of overgrowth. The Gs. sacculifer show definite signs of alteration and exhibit variable preservation, ranging from fair to poor; some specimens show minor overgrowth and internal recrystallization but retain original features such as pores, spine pits, and internal testwall growth structure, whereas in other specimens the recrystallization and overgrowth disguise many of the original features. Secondary electron and BSE-TOPO SEM images show that coccolith calcite preservation is moderate or moderate to poor. Slight to moderate etching has removed central heterococcolith features, and a small amount of secondary overgrowth is also visible. Energy dispersive spectroscopy analyses indicate that the main sedimentary components of the fine fraction sediment are biogenic CaCO3 and SiO2, with some marine barite. Based on the investigations in this data report, geochemical analyses on benthic foraminifers are unlikely to be affected by preservation, although geochemical analyses on the planktonic foraminifers should be treated cautiously because of the fair to poor and highly variable preservation

A play of voices in marine conservation: Human experiences of fishery closures in Zanzibar

Based on stories written by Elizabeth (Liz) Drury O’Neill. These stories were directly taken from the research transcripts of OctoPINTS’ fieldwork in 2019. The stories were edited into a play by Tim Daw and Emilie Lindkvist. Kiswahili translation was made by Irene Musa and Andrew Wamukota. Layout and editing by Jineth Berrío-Marínez. Front page illustration by Krisztina Jónás. In English AND Kiswahili. This play script is an outcome of the OctoPINTS project https://octopints.wordpress.com/, a research project funded jointly by VR the Swedish Research Council, Sida the Swedish International Development Cooperation Agency, Formas the Swedish Research Council for Sustainable Development and Forte (Dnr 2018-05862). With additional support from the Stockholm Resilience Centre, the University of Dar es Salaam, and Pwani University. With huge thanks to Mwambao coastal community network, fieldwork hosts and collaborators

A benthic foraminifera perspective of the Late Miocene-Early Pliocene Biogenic Bloom at ODP Site 1085 (Southeast Atlantic Ocean)

The Late Miocene-Early Pliocene Biogenic Bloom (ca. 9.0–3.5 Ma) was a phase of high marine biological productivity documented globally at multiple ocean sites, related to an increase in nutrient input and/or a significant reorganization of nutrients in the oceans. Here, we studied the Biogenic Bloom at Ocean Drilling Program (ODP) Site 1085 in the Southeast Atlantic Ocean, additionally providing an updated age model based on calcareous nannofossil biostratigraphy. During the event, we identified four intervals characterised by distinct benthic foraminiferal assemblages, suggesting changes in paleoenvironmental/paleoceanographic conditions. The Biogenic Bloom extends from 8.1 to 3.0 Ma at Site 1085, as detected by different proxies such as linear sedimentation rates, carbonate mass accumulation rates, benthic foraminiferal indices and assemblage data. The inferred paleoenvironmental changes allowed us to differentiate four intervals within the Biogenic Bloom. From 8.1 to 5.2 Ma and from 3.8 to 3.0 Ma, the high benthic foraminiferal accumulation rates (BFARs) and the abundance of phytodetritus-exploiting taxa point to highly seasonal phytoplankton blooms. Between 5.2 and 4.8 Ma, we document short-term fluctuations between well‑oxygenated conditions with transient input of phytodetritus and phases of low oxygen eutrophic conditions. Between 4.8 and 3.8 Ma, a decrease in opportunistic species and an increase in eutrophic taxa likely suggest a switch to a higher food supply to the seafloor. Our data shows that the onset of the Biogenic Bloom was synchronous with other global well-dated records and its end appears to align with other Atlantic records. Lastly, our findings support the hypothesis that the Biogenic Bloom was not a single productivity event, but a complex event made up of several short-lived, high-productivity regimes with different driving forces

Stories and Simulations: Compliance and Periodic Octopus Closures in the WIO region

A three hour online workshop was hosted by OctoPINTS with experts on temporal octopus closures in the WIO region. The objectives of this meeting were to: Reconnect and build on the network established at Wiomsa 2019 and facilitate discussions between expert participants. Share and discuss findings from our empirical work on perceptions of closures and compliance in Zanzibar. Share and invite comments on the scope and behaviour of our octopus closure agent-based model. The workshop demonstrated how a combined fieldwork, modelling and expert consultation process helps to develop systems understanding. The sharing of the fieldwork results through storytelling, painting a deep and rich description of how local fishery actors perceived the closure model’s intricate dilemmas around compliance. The sharing of the agent based model’s design, such as fishery actors and processes around compliance and patrolling, sparked discussions around interactions of the different components in the closure model. These two approaches of studying and presenting the issues around interventions herein the closure model in turn lead to deeper discussions around the social and ecological dynamics embedded in the closure model

Tracking the nature and trajectory of social support in Facebook mutual aid groups during the COVID-19 pandemic.

At the onset of the COVID-19 pandemic, thousands of mutual aid groups were established on social media and operated as platforms through which people could offer or request social support. Considering the importance of Facebook mutual aid groups during the early stages of the COVID-19 pandemic in the United Kingdom but also the lack of empirical research regarding the trajectories and types of social support rendered available through the groups, our aims in this paper are threefold; first, to examine the trajectory of social support-related activity during the period between March-December 2020; second, to compare offers and requests of support during the peaks of the first and second waves; third to provide a rich analysis of the types of social support that were offered or requested through the online mutual aid groups. Quantitative findings suggest that online social support activity declined soon after the peak of the first pandemic wave and, at least in Facebook mutual aid groups, did not reach the levels observed during the first wave. Also, the number of offers of support during the first wave was higher compared to offers during the second wave, and similar was the case for requests for support. Additionally, offers for support were higher compared to requests for support during both the first and second waves. Finally, qualitative analysis showed that people used the Facebook mutual aid groups to offer and request various types of practical, emotional, and informational support. Limitations as well as implications of our study are considered. [Abstract copyright: © 2022 The Authors.