We present new high‐resolution pollen records combined with palaeoceanographic proxies from the same samples in deep‐sea cores SHAK06‐5K and MD01‐2444 on the southwestern Iberian Margin, documenting regional vegetation responses to orbital and millennial‐scale climate changes over the last 28 ka. The chronology of these records is based on high‐resolution radiocarbon dates of monospecific samples of the planktonic foraminifera Globigerina bulloides, measured from SHAK06‐5K and MD01‐2444 and aligned using an automated stratigraphical alignment method. Changes in temperate and steppe vegetation during Marine Isotope Stage 2 are closely coupled with sea surface temperature (SST) and global ice‐volume changes. The peak expansion of thermophilous woodland between ~10.1 and 8.4 cal ka bp lags behind the boreal summer insolation maximum by ~2 ka, possibly arising from residual high‐latitude ice‐sheets into the Holocene. Rapid changes in pollen percentages are coeval with abrupt transitions in SSTs, precipitation and winter temperature at the onset and end of Heinrich Stadial 2, the ice‐rafted debris event and end of Heinrich Stadial 1, and the onset of the Younger Dryas, suggesting extrinsically forced southwestern Iberian ecosystem changes by abrupt North Atlantic climate events. In contrast, the abrupt decline in thermophilous elements at ~7.8 cal ka bp indicates an intrinsically mediated abrupt vegetation response to the gradually declining boreal insolation, potentially resulting from the crossing of a seasonality of precipitation threshold.
Here, we explore the importance of export productivity versus anoxia in the formation of sedimentary layers with enhanced total organic carbon (TOC) content. We use geochemical, sedimentological and micropaleontological records from two SW Sicily outcropping successions, Lido Rosello (LR) and Punta di Maiata (PM), over three mid-Pliocene precession-forced climate cycles (4.7 -4.6 million years ago [Ma]). Grey marls, deposited during precession minima, show enhanced TOC in both records. We suggest that basin-wide, low-oxygenated bottom-waters, resulting from freshwater-induced stratification during precession minimum, was integral to preserving grey marl TOC. Furthermore, prolonged eastern Mediterranean stratification may have produced a deep chlorophyll maximum (DCM), leading to 'shade-flora' dominated productivity. The LR succession displays two unique laminated layers containing enhanced TOC. These laminations do not occur at specific times in the precession cycle or in time-equivalent PM samples. They are likely to have been produced by an intermittent dysoxic/anoxic pool at LR, caused by a local depression, which enhanced TOC preservation. Consequently, the laminations provide a rare window into 'true' eastern Mediterranean productivity conditions during precession maxima, as organic matter is typically poorly preserved during these period due to enhanced ventilation. The laminated 'windows' indicate that eastern Mediterranean export productivity may not have been significantly lower during precession maxima compared to precession minima, as previously thought. During these periods, productivity conditions are likely to have been comparable to the modern eastern Mediterranean, with a spring-bloom caused by enhanced winter/spring deep-water mixing preceding a summer 'shade-flora' bloom caused by a summer-stratification induced DCM.
This article highlights both over-reliance on legal perspectives in the study of paradiplomacy at the expense of more dynamic understandings of agency, and also the affective force of waiting and other temporal states on political subject formation.Empirically, we report the results of a longitudinal study on Gibraltarians' concerns over the Gibraltar-Spain frontier. By comparing data from two identical surveys conducted a year apart during the period between the Brexit referendum and the (as yet incomplete) legal withdrawal, we trace the force of the incomplete event on political subjectivities.Conceptualising our findings through assemblage theory and paradiplomacy, we highlight that the intensity of the event has heightened Gibraltarians' dissatisfaction with their constitutional reliance on the UK to resolve Brexit in a way advantageous for Gibraltar. A minor shift occurred in the year studied towards more agentic proscriptions of what the Government of Gibraltar ought to do to resolve Brexit. Quantitative analysis reveals that younger respondents tend to emphasise this more agentic view, while older respondentsThe force of events: the 'Brexit interval' and popular aspirations for Gibraltarian diplomacy 2 tend to advocate further lobbying of the UK or feel Gibraltar has a complete lack of agency.Qualitative analysis of the respondents' policy proscriptions reveals a complex set of views within each perspective on agency.
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