Quaternary marine deposits of the Springdale - Hall's Bay area, Newfoundland

Quaternary glaciomarine deposits form a complex sedimentary succession in the Springdale - Hall's Bay area of north-central Newfoundland. Marine incursion due to isostatic depression was extensive throughout the Indian Brook and South Brook valleys, reaching at least 10 km inland. Sedimentological, palaeontological, and geomorphological analyses have permitted reconstruction of the history of sea level change for the area since 12,470 years B.P. Stratified coarse sediment sequences with surfaces ranging up to 75 m above the present sea level were a result of higher sea-level stands. A succession of ice-contact deltas, representing the proximal units associated with the marine incursion, and a series of successively lower terraces (indicating isostatic rebound) are present. Most of the deposits were formed in ice-contact fan-deltas, but deposits at two sites are interpreted as ice-distal fans. Clay and silt were deposited by a combination of suspension settling and sediment gravity flows in low energy, distal locations. Dropstones indicative of ice rafting are present throughout the clay strata. Vanadium concentrations in these deposits indicate deposition in brackish-marine environments. Shells of Mya arenaria, BaIanus hameri, Macoma ballhica, and Hiatella arclica found in life positions also indicate brackish depositional environments. Four 14C dates were obtained from the marine fossils giving an age range of 11,300 ± 120 to 12,470 ± 380 years B.P. This suggests that the silt and clay deposits represent the distal sediments associated with glaciomarine delta formation. RÉSUMÉ Les dépôts glaciomarins d'âge Quaternaire forment une succession sédimentaire complexe dans la région Springdale - baie Hall, dans le centre nord de Terre-Neuve. L'incursion marine reliée à l'enfoncement isostatique à affecté de grandes surfaces dans les valines des ruisseaux Indian et South, pénétrant jusqu'à 10 km à l'intérieur des terres. Les analyses sédimentologiques, paléontologiques et géomorphologiques ont permis de reconstruire l'histoire des variations du niveau marin pour la région dépuis 12,470 B.P. La présence de séquences sédimentaires grossieres et stratifies sont le produit de niveaux marins plus élevés. Il y à une succession de deltas formes au contact du glacier et de la mer, qui représentent les unités proximales associées à l'incursion marine, et une seiie de terrasses à des niveaux successivement plus bas (qui indiquent un rebondissement isostatique). La plupart des dépôts se sont formée dans des cones deltaiques au contact du glacier et de la mer mais, à deux endroits, les dépôts sont interpréts comme étant des cones formés à distance du glacier. L'argile et le silt ont été déposés par une combinaison de suspension et de courants de turbidité en des milieux distaux et de basse énergie. Des cailloux de délestage, indicateurs de transport par glaces flottantes, sont présents dans toutes les couches d'argile. Les concentrations en vanadium de ces dépôts indiquent des milieux marins saumatres. Les coquilles de Mya arenaria, de Balanus hameri, de Macoma ballhica, et de Hiatella artica, trouvdes en position de vie, indiquent aussi des milieux de déposition saumatres. Quatre datations par 14C obtenues sur des fossiles marins ont donné un intervallede 11,300 ± 120 à 12,470 ±380 B.P. Ceci suggére que les dépôts de silt et d'argile représentent des sédiments distaux associés à la formation de deltas glaciomarins. [Traduit par le journal

Late Quaternary Relative Sea-Level Change on the West Coast of Newfoundland

Two revised relative sea-level (RSL) curves are presented for the Port au Choix to Daniel’s Harbour area of the Great Northern Peninsula, northwestern Newfoundland. Both curves are similar, showing continuous emergence of 120-140 m between 14 700 cal BP and present. The half-life of exponential curves fit to the RSL data is 1400 years and the rate of emergence varies from ~2.3 m per century prior to 10 000 cal BP to ~0.13 m per century since 5000 cal BP. The curves fit a general pattern of RSL history along the west coast of Newfoundland, where there is a southward transition from solely emergence to emergence followed by submergence. Isostatic depression curves are generated for four RSL records spanning the west coast. Almost double the crustal depression is recorded to the northwest, reflecting the greater glacioisostatic loading by the Laurentide Ice Sheet over southern Labrador and Québec compared to a smaller loading centre by a regional ice complex over Newfoundland. Only the St. George’s Bay RSL record in the southwest appears to show evidence for a proglacial forebulge, when at 6000 cal BP an isostatic ridge of 4 m amplitude begins to collapse.Deux courbes du niveau marin relatif (NMR) sont présentées pour la région allant de Port-au-Choix à Daniel’s Harbour sur la Grande Péninsule Nord, au nord-ouest de Terre-Neuve. Les deux courbes sont semblables, montrant une émergence continue de 120 à 140 m entre 14 700 cal BP et l’actuel. La demi-vie des courbes exponentielles ajustées au NMR est de 1400 ans, et le taux d’émergence varie de ~2.3 m par siècle avant 10 000 cal BP à ~0.13 m par siècle depuis 5000 cal BP. Les courbes s’ajustent au modèle général de l’histoire du NMR de la côte ouest de Terre-Neuve, où il existe une transition d’émergence seule à une émergence suivie d’une submergence, en allant vers le sud. Des courbes de dépressions isostatiques préliminaires sont générées pour quatre chronologies du NMR couvrant la côte ouest. Presque le double de la dépression de la croûte est enregistré au nord-ouest, reflétant la charge glacio-isostatique plus grande de l’Inlandsis Laurentidien sur le sud du Labrador et du Québec comparée à la charge plus faible du complexe glaciaire régional localisé sur Terre-Neuve. Seules les données du NMR de St. George’s Bay, au sud-ouest, semble démontrer l’affaissement du bourrelet périphérique lorsqu’une vague isostatique de 4 m d’amplitude commence à s’effondrer vers 6000 cal BP

Why equity is fundamental in climate change policy research

The editorial article rebuts the common assertions that equity is irrelevant in a post Paris climate research and argue that analyses of equity and justice are essential for our ability to understand climate politics and contribute to concrete efforts to achieve adequate, fair and enduring climate action for present and future generations

Identifying a Safe and Just Corridor for People and the Planet

Keeping the Earth system in a stable and resilient state, to safeguard Earth's life support systems while ensuring that Earth's benefits, risks, and related responsibilities are equitably shared, constitutes the grand challenge for human development in the Anthropocene. Here, we describe a framework that the recently formed Earth Commission will use to define and quantify target ranges for a “safe and just corridor” that meets these goals. Although “safe” and “just” Earth system targets are interrelated, we see safe as primarily referring to a stable Earth system and just targets as being associated with meeting human needs and reducing exposure to risks. To align safe and just dimensions, we propose to address the equity dimensions of each safe target for Earth system regulating systems and processes. The more stringent of the safe or just target ranges then defines the corridor. Identifying levers of social transformation aimed at meeting the safe and just targets and challenges associated with translating the corridor to actors at multiple scales present scope for future work

Identifying a Safe and Just Corridor for People and the Planet

Keeping the Earth system in a stable and resilient state, to safeguard Earth's life support systems while ensuring that Earth's benefits, risks, and related responsibilities are equitably shared, constitutes the grand challenge for human development in the Anthropocene. Here, we describe a framework that the recently formed Earth Commission will use to define and quantify target ranges for a “safe and just corridor” that meets these goals. Although “safe” and “just” Earth system targets are interrelated, we see safe as primarily referring to a stable Earth system and just targets as being associated with meeting human needs and reducing exposure to risks. To align safe and just dimensions, we propose to address the equity dimensions of each safe target for Earth system regulating systems and processes. The more stringent of the safe or just target ranges then defines the corridor. Identifying levers of social transformation aimed at meeting the safe and just targets and challenges associated with translating the corridor to actors at multiple scales present scope for future work

Impacts of meeting minimum access on critical earth systems amidst the Great Inequality

The Sustainable Development Goals aim to improve access to resources and services, reduce environmental degradation, eradicate poverty and reduce inequality. However, the magnitude of the environmental burden that would arise from meeting the needs of the poorest is under debate—especially when compared to much larger burdens from the rich. We show that the ‘Great Acceleration’ of human impacts was characterized by a ‘Great Inequality’ in using and damaging the environment. We then operationalize ‘just access’ to minimum energy, water, food and infrastructure. We show that achieving just access in 2018, with existing inequalities, technologies and behaviours, would have produced 2–26% additional impacts on the Earth’s natural systems of climate, water, land and nutrients—thus further crossing planetary boundaries. These hypothetical impacts, caused by about a third of humanity, equalled those caused by the wealthiest 1–4%. Technological and behavioural changes thus far, while important, did not deliver just access within a stable Earth system. Achieving these goals therefore calls for a radical redistribution of resources

Achieving a nature- and people-positive future

Despite decades of increasing investment in conservation, we have not succeeded in “bending the curve” of biodiversity decline. Efforts to meet new targets and goals for the next three decades risk repeating this outcome due to three factors: neglect of increasing drivers of decline; unrealistic expectations and time frames of biodiversity recovery; and insufficient attention to justice within and between generations and across countries. Our Earth system justice approach identifies six sets of actions that when tackled simultaneously address these failings: (1) reduce and reverse direct and indirect drivers causing decline; (2) halt and reverse biodiversity loss; (3) restore and regenerate biodiversity to a safe state; (4) raise minimum wellbeing for all; (5) eliminate over-consumption and excesses associated with accumulation of capital; and (6) uphold and respect the rights and responsibilities of all communities, present and future. Current conservation campaigns primarily address actions 2 and 3, with urgent upscaling of actions 1, 4, 5, and 6 needed to help deliver the post-2020 global biodiversity framework

Impacts of 1.5°C Global Warming on Natural and Human Systems

An IPCC Special Report on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate povert