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A step-by-step guide to sustainability, this book is brimming with creative pupil-led projects for putting your eco-dreams into action. Begins with introduction to concept of an eco school, a summary of principles of environmental management and suggests opportunities for pupils to lead the exciting projects.

The effect of wind‐induced vertical velocity on the meridional coherence of Atlantic meridional overtuning circulation (AMOC) is examined using theory, observations, and a numerical model. Two cases are considered: (a) the AMOC computed in depth coordinates and (b) the AMOC computed in isopycnal coordinates. In depth space, the difference between the AMOC at different latitudes is largely explained by vertical transport across the 1000m$1000\\,\\mathrm{m}$depth surface induced by Ekman pumping. In density space, this difference is explained by Ekman‐driven heave of the neutral surface separating the upper and lower limbs. This adiabatic “sloshing” changes the relative volumes of the upper and lower AMOC limbs, obscuring the distribution and advection of the diapycnal transports which characterize the AMOC. Plain Language Summary The Atlantic meridional overturning circulation (AMOC) is classically viewed as a continuous “conveyor” transporting warm water northward in its upper limb and cold water southward in its lower limb. It is natural to assume, then, that fluctuations in the AMOC strength are synchronous across latitude. However, observations from the last decade have drawn this interpretation into question, as the subtropical and subpolar AMOC show no evidence of temporal coherence. Here, we demonstrate that much of this lack of coherence can be explained by vertical velocities induced by wind over the North Atlantic. Key Point Lack of meridional coherence in observed Atlantic meridional overtuning circulation can largely be explained by Ekman pumping

Weight reduction is essential for improving health outcomes in people with obesity and type 2 diabetes. We assessed the efficacy and safety of tirzepatide, a glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonist, versus placebo, for weight management in people living with obesity and type 2 diabetes. This phase 3, double-blind, randomised, placebo-controlled trial was conducted in seven countries. Adults (aged ≥18 years) with a body-mass index (BMI) of 27 kg/m2 or higher and glycated haemoglobin (HbA1c) of 7–10% (53–86 mmol/mol) were randomly assigned (1:1:1), using a computer-generated random sequence via a validated interactive web-response system, to receive either once-weekly, subcutaneous tirzepatide (10 mg or 15 mg) or placebo for 72 weeks. All participants, investigators, and the sponsor were masked to treatment assignment. Coprimary endpoints were the percent change in bodyweight from baseline and bodyweight reduction of 5% or higher. The treatment-regimen estimand assessed effects regardless of treatment discontinuation or initiation of antihyperglycaemic rescue therapy. Efficacy and safety endpoints were analysed with data from all randomly assigned participants (intention-to-treat population). This trial is registered with ClinicalTrials.gov, NCT04657003. Between March 29, 2021, and April 10, 2023, of 1514 adults assessed for eligibility, 938 (mean age 54·2 years [SD 10·6], 476 [51%] were female, 710 [76%] were White, and 561 [60%] were Hispanic or Latino) were randomly assigned and received at least one dose of tirzepatide 10 mg (n=312), tirzepatide 15 mg (n=311), or placebo (n=315). Baseline mean bodyweight was 100·7 kg (SD 21·1), BMI 36·1 kg/m2 (SD 6·6), and HbA1c 8·02% (SD 0·89; 64·1 mmol/mol [SD 9·7]). Least-squares mean change in bodyweight at week 72 with tirzepatide 10 mg and 15 mg was –12·8% (SE 0·6) and –14·7% (0·5), respectively, and –3·2% (0·5) with placebo, resulting in estimated treatment differences versus placebo of –9·6% percentage points (95% CI –11·1 to –8·1) with tirzepatide 10 mg and –11·6% percentage points (–13·0 to –10·1) with tirzepatide 15 mg (all p<0·0001). More participants treated with tirzepatide versus placebo met bodyweight reduction thresholds of 5% or higher (79–83% vs 32%). The most frequent adverse events with tirzepatide were gastrointestinal-related, including nausea, diarrhoea, and vomiting and were mostly mild to moderate in severity, with few events leading to treatment discontinuation (<5%). Serious adverse events were reported by 68 (7%) participants overall and two deaths occurred in the tirzepatide 10 mg group, but deaths were not considered to be related to the study treatment by the investigator. In this 72-week trial in adults living with obesity and type 2 diabetes, once-weekly tirzepatide 10 mg and 15 mg provided substantial and clinically meaningful reduction in bodyweight, with a safety profile that was similar to other incretin-based therapies for weight management. Eli Lilly and Company.

A pneumococcal conjugate vaccine (PCV) specifically focused on serotypes associated with adult residual disease burden is urgently needed. We aimed to assess V116, an investigational 21-valent PCV, that contains pneumococcal polysaccharides (PnPs), which account for 74–94% of invasive pneumococcal disease in adults aged 65 years or older. We did a phase 1/2, randomised, double-blind, active comparator-controlled, multicentre, non-inferiority and superiority trial. The phase 1 study was done at two clinical sites in the USA, and the phase 2 study was done in 18 clinical sites in the USA. Eligible participants were healthy adults with or without chronic medical conditions assessed as stable, aged 18–49 years in the phase 1 trial and aged 50 years or older in the phase 2 trial. Participants were excluded if they had a history of invasive pneumococcal disease or other culture-positive pneumococcal disease within the past 3 years, known hypersensitivity to a vaccine component, known or suspected impairment of immunological function, were pregnant or were breastfeeding, or had previously received any pneumococcal vaccine. Participants had to abstain from sexual activity or use protocol approved contraception. All participants were centrally randomly assigned to a vaccine group using an interactive response technology system. Participants and investigators were masked to group assignment. In phase 1, participants were randomly assigned (1:1:1) to receive a single dose of V116-1 (2 μg per pneumococcal polysaccharide [PnP] per 0·5 mL) or V116-2 (4 μg per PnP per 1·0 mL) or the 23-valent unconjugated PnP vaccine, PPSV23 (25 μg per PnP per 0·5 mL). In phase 2, participants were randomly assigned (1:1) to receive one dose of V116 (4 μg per PnP per 1·0 mL) or PPSV23 (25 μg per PnP per 0·5 mL), stratified by age. Safety analyses included all randomly assigned participants who received study vaccine; immunogenicity analyses were per protocol. For both phases, the primary safety outcome was the proportion of participants with solicited injection-site adverse events and solicited systemic adverse events up to day 5 after vaccination and the proportion of participants with vaccine-related serious adverse events to 6 months after vaccination. In phase 2, primary immunogenicity outcomes were to test non-inferiority of V116 compared with PPSV23 as measured by serotype-specific opsonophagocytic antibody geometric mean titres (OPA-GMT) ratios for the serotypes common to the two vaccines at 30 days after vaccination (using a 0·33 margin) and to test superiority of V116 compared with PPSV23 as measured by serotype-specific OPA-GMT ratios for the serotypes unique to V116 at 30 days after vaccination (using a 1·0 margin). This trial is registered with Clinicaltrials.gov, NCT04168190. Between Dec 6 and 26, 2019, 92 volunteers were screened and 90 (98%) enrolled for phase 1 (59 [66%] women; 31 [34%] men); 30 participants were assigned to each group and received study vaccine. 30 (100%) participants in the V116-1 group, 29 (97%) in the V116-2 group, and 30 (100%) participants in the PPSV23 group were included in the per-protocol immunogenicity evaluation. From Sept 23, 2020, to Jan 12, 2021, 527 volunteers were screened, and 510 (97%) participants were enrolled in the phase 2 trial. 508 participants (>99%; 254 [100%] of 254 participants randomly assigned to the V116 group and 254 [99%] of 256 randomly assigned to PPSV23 group) received study vaccine (281 [55%] women; 227 [45%] men). 252 (99%) of 254 of participants in the V116 group and 254 (99%) of 256 participants in the PPSV23 group were included in the primary immunogenicity analyses. There were no vaccine-related serious adverse events or vaccine-related deaths in either study phase. In both phases, the most common solicited injection site adverse event was injection site pain (phase 1 22 [73%] participants in V116-1 group, 23 [77%] participants in V116-2 group, and 17 [57%] participants in the PPSV23 group; phase 2 118 [46%] of 254 participants in the V116 group and 96 [38%] of 254 in the PPSV23 group]. The most common solicited systemic adverse events in phase 1 was fatigue (eight [27%] participants in the V116-1 group, eight [27%] participants in the V116-2 group, and five [17%] participants in PPSV23 group) and myalgia (eight [27%] participants in the V116-1 group, nine (30%) participants in the V116-2 group, and four (13%) participants in the PPSV23 group]. In phase 2, the most frequently reported solicited systemic adverse event was fatigue (49 [19%] participants in V116 group, and 31 [12%] participants in PPSV23 group). In both phases, most of the solicited adverse events in all vaccine groups were mild and of short duration (≤3 days). V116 met non-inferiority criteria compared with PPSV23 for the 12 shared serotypes and met superiority criteria compared to PPSV23 for the nine unique serotypes. V116 was well tolerated with a safety profile generally similar to PPSV23; consistent with licensed pneumococcal conjugate vaccines. Functional OPA antibodies were induced to all V116 vaccine serotypes. The vaccine was non-inferior to PPSV23 for the 12 serotypes common to both vaccines and superior to PPSV23 for the nine unique serotypes in V116. Our findings support the development of V116 for prevention of pneumococcal disease in adults. Merck Sharp & Dohme, subsidiary of Merck & Co, Rahway, NJ, USA.

Variability of the Atlantic Meridional Overturning Circulation (MOC) has drawn extensive attention due to its impact on the global redistribution of heat and freshwater. Here we present the latest time series (2014–2022) of the Overturning in the Subpolar North Atlantic Program and characterize MOC interannual variability. We find that any single boundary current captures ∼30% of subpolar MOC interannual variability. However, to fully resolve MOC variability, a wide swath across the eastern subpolar basin is needed; in the Labrador Sea both boundaries are needed. Through a volume budget analysis for the subpolar basins' lower limbs, we estimate the magnitude of unresolved processes (e.g., diapycnal mixing) required to close the mean budget (∼2 Sv). We find that in the eastern subpolar basin surface‐forced transformation variability is linked to lower limb volume variability, which translates to MOC changes within the same year. In contrast, this linkage is weak in the Labrador Sea.

Interactions between ice masses and the ocean are key couplings in the global climate system. In many cases, these interactions occur through glacial fjords, which are long, deep, and narrow troughs connecting the open ocean to marine-terminating glaciers. By controlling the fluxes of ocean heat towards the ice sheet and ice sheet freshwater towards the ocean, glacial fjords play an important role in modulating ice sheet mass loss and the impacts of freshwater on ocean circulation. Yet, these dynamics occur at small scales that are challenging to resolve in earth system models and hence are often ignored, represented in an ad-hoc manner, or studied using expensive high-resolution models that are limited in scope. Here, we propose a means of capturing glacial fjord dynamics at negligible computational expense in the form of a “reduced-physics” model (FjordRPM) that resembles a “1.5-dimensional” or box model. We describe the design and physical parameterisations in the model and demonstrate its ability to capture important modes of glacial fjord circulation by comparing it against a general circulation model in idealised and realistic simulations. We suggest that the model is a useful tool for understanding fjord dynamics and a promising approach for representing glacial fjord processes within large-scale models or climate and sea level projection efforts.

The Atlantic meridional overturning circulation (AMOC) is expected to decline dramatically over the 21st century, with severe impacts for Northern Hemisphere climate. After 20 years of sustained monitoring in the subtropics, a detectable AMOC weakening trend is now beginning to emerge. However, continuous observations at subpolar latitudes are currently too short-lived to determine any weakening signal above the large-amplitude interannual variability. Here, we introduce a new subpolar observing configuration, SCOTIA (Scotland–Canada overturning array), combining parts of the existing OSNAP mooring array with scattered CTD and Argo data, to extend the record of subpolar AMOC backward in time to cover the subtropical monitoring period, 2004–2024. SCOTIA facilitates a rigorous comparison of the decadal-scale variability in transports and overturning at subpolar and subtropical latitudes. Our results show subpolar AMOC varies on pentadal to decadal timescales with an amplitude comparable to that observed in the subtropics. Anomalously high overturning during 2016–2020 was driven by increased southward transports in the density classes associated with Labrador Sea Water. We find no statistically significant trend in subpolar AMOC during the period 2004–2024.

Eastern boundary currents are some of the most energetic features of the global ocean, contributing significantly to meridional mass, heat, and salt transports. We take a new look at the form of an oceanic slope current in equilibrium with oceanic density gradients. We depth integrate the linearized x and y momentum and continuity equations and assume an equilibrium force balance in the along-slope direction (no along-slope variation in the along-slope flow) and zero cross-slope flow at a coastal boundary. We relate the bottom stress to a bottom velocity via a simple boundary friction law (the precise details are easily modified) and then derive an expression for the slope current velocity by integrating upward including thermal wind shear. This provides an expression for the slope current as a function of depth and of cross-slope coordinate, dependent on the oceanic density field and surface and bottom stresses. This new expression for the slope current allows for more general forms of oceanic density fields than have been treated previously. Wind stress is also now considered. The emphasis here is on understanding the simplified equilibrium force balance rather than the evolution toward that balance. There is a direct relationship between the slope current strength, friction, and along-slope forcing (e.g., wind), and also between the total along-slope forcing and bottom Ekman transport, illustrating that “slippery” bottom boundaries in literature are a direct consequence of unrealistically assuming zero along-slope pressure gradient. We demonstrate the utility of the new expression by comparison with a high-resolution hydrodynamic numerical model.

The Atlantic meridional overturning circulation (AMOC) has a notable seasonal component. This influences the jet stream and the location, frequency, and intensity of extreme weather events. Understanding this seasonality is important for mitigating the impacts of AMOC changes on European weather and climate. Here, we place meridional overturning and fluxes in a coherent framework. This framework highlights the integral relationship between meridional overturning circulation and property transports, both being functions purely of the overturning streamfunction Ψ. Using this framework, we examine the seasonality observed in overturning and density, temperature, and freshwater fluxes at the Overturning in the Subpolar North Atlantic Program (OSNAP) line in the subpolar North Atlantic. We find the seasonal cycle of the MOC metric (the standard measure of overturning, defined as the maximum of the overturning streamfunction) to be dominated by Ekman transports and the large-scale seasonal cycle of surface density; heat flux to be dominated by barotropic velocity variability; the seasonal cycle of freshwater flux to be dominated by a combination of barotropic velocities and the salinity in the western boundary current; and density flux to reflect a broad range of characteristics and processes. We show that the MOC metric is a poor predictor, on seasonal timescales, of either density fluxes or the more societally relevant ocean heat and freshwater transports. This is due to each of these metrics responding to different physical processes. The MOC metric, on seasonal timescales at least, has very high sensitivity to near-surface physical characteristics in a limited geographical area. These characteristics are not necessarily reflective of the fundamental processes driving overturning. Therefore, we suggest caution in the use of the standard MOC metric when studying overturning and the routine use of the density flux as a valuable additional overturning metric.

The Rockall Trough, northwest of Scotland and Ireland, is a key conduit for the North Atlantic Current (NAC) and European Slope Current (ESC) transporting heat and salt toward the Nordic Seas and Arctic Ocean while mediating exchanges between the open ocean and the European shelf. We present a decade-long record of Rockall Trough circulation from the Ellett Array providing the first continuous estimates of heat and freshwater transport between 2014 and 2024. We develop a methodology that combines the high spatial resolution of gliders with the high temporal resolution of moorings and ocean reanalysis output producing continuous eastern boundary velocity fields of the ESC for integration into the full Rockall Trough transport product. This approach improves the mean structure of the ESC, capturing the southward undercurrent previously unresolved and enhancing the ability to reproduce extreme, likely mesoscale, transport events. The Rockall Trough transport is dominated by the NAC flowing through the mid basin, exhibiting multi-year variability consistent with changes in the subpolar gyre and the mid-2010s cold freshwater anomaly. The ESC acts as a secondary driver, is not correlated with the NAC and is influenced by along-slope wind stress. Since 2022, warmer and saltier conditions, amplified by the 2023 extreme North Atlantic marine heatwave, have strengthened northward volume, heat, and salt transport through the Ellett Array. Our results highlight the value of sustained glider-based boundary current observations for Atlantic climate monitoring and demonstrate that the combined mooring–glider framework provides a robust and transferable approach for long-term ocean transport monitoring.