Southern Ocean carbon-wind stress feedback

The Southern Ocean is the largest sink of anthropogenic carbon in the present-day climate. Here, Southern Ocean pCO2pCO2 and its dependence on wind forcing are investigated using an equilibrium mixed layer carbon budget. This budget is used to derive an expression for Southern Ocean pCO2pCO2 sensitivity to wind stress. Southern Ocean pCO2pCO2 is found to vary as the square root of area-mean wind stress, arising from the dominance of vertical mixing over other processes such as lateral Ekman transport. The expression for p\hbox {CO} _ {2} is validated using idealised coarse-resolution ocean numerical experiments. Additionally, we show that increased (decreased) stratification through surface warming reduces (increases) the sensitivity of the Southern Ocean pCO2pCO2 to wind stress. The scaling is then used to estimate the wind-stress induced changes of atmospheric pCO2pCO2 in CMIP5 models using only a handful of parameters. The scaling is further used to model the anthropogenic carbon sink, showing a long-term reversal of the Southern Ocean sink for large wind stress strength

Quantification of ocean heat uptake from changes in atmospheric O2 and CO2 composition

The ocean is the main source of thermal inertia in the climate system. Ocean heat uptake during recent decades has been quantified using ocean temperature measurements. However, these estimates all use the same imperfect ocean dataset and share additional uncertainty due to sparse coverage, especially before 2007. Here, we provide an independent estimate by using measurements of atmospheric oxygen (O2) and carbon dioxide (CO2) – levels of which increase as the ocean warms and releases gases – as a whole ocean thermometer. We show that the ocean gained 1.29 ± 0.79 × 1022 Joules of heat per year between 1991 and 2016, equivalent to a planetary energy imbalance of 0.80 ± 0.49 W watts per square metre of Earth’s surface. We also find that the ocean-warming effect that led to the outgassing of O2 and CO2 can be isolated from the direct effects of anthropogenic emissions and CO2 sinks. Our result – which relies on high-precision O2 atmospheric measurements dating back to 1991 – leverages an integrative Earth system approach and provides much needed independent confirmation of heat uptake estimated from ocean data

General attitudes towards marriage scale: psychometric properties in Malaysian adolescents of divorced families

Attitudes towards marriage in adolescence may influence the relationship quality in later years. There exist many measures of attitudes towards marriage which were validated among adolescents from two-parent family in the Western context. There is a need to validate measure of attitudes towards marriage in different countries. This study examined the psychometric properties of the Malay version of general attitudes towards marriage scale in a sample of 480 adolescents from divorced families in Malaysia. Exploratory factor analysis yielded a two-factor structure of general attitudes towards marriage scale, which explained for 60% of the variance. Additionally, the two-factor structure of general attitudes towards marriage scale demonstrated good fit to data in the confirmatory factor analysis (non-normed fit index = .941, comparative fit index = .958, root mean square error of estimation = .087, and χ 2/df = 4.615). Overall, the general attitudes towards marriage scale exhibited good internal consistency (α = .901), which supports the reliability of the instrument. The significant relationships between general attitudes towards marriage scale and other constructs also provided evidences to the convergent validity (r = .761, p < .001 with intent to marry, r = −.170, p < .001 with overt inter-parental conflict, and r = .523, p < .001 with mother–adolescent relationship). Significant gender difference was found in the report of general attitudes towards marriage scale (t = −2.265, p < .05). Thus, the translated general attitudes towards marriage scale is a reliable, valid, and practical instrument to measure attitudes towards marriage among Malaysian adolescents in divorced family setting

The influence of Southern Ocean winds on the North Atlantic carbon sink

Observed and predicted increases in Southern Ocean winds are thought to upwell deep ocean carbon and increase atmospheric CO2. However, Southern Ocean dynamics affect biogeochemistry and circulation pathways on a global scale. Using idealised MITgcm simulations, we demonstrate that an increase in Southern Ocean winds reduces the carbon sink in the North Atlantic sub-polar gyre. The increase in atmospheric CO2 due to the reduction of the North Atlantic carbon sink is shown to be of the same magnitude as the increase in atmospheric CO2 due to Southern Ocean outgassing. The mechanism can be described as follows: The increase in Southern Ocean winds leads to an increase in upper ocean northward nutrient transport. Biological productivity is therefore enhanced in the tropics, which alters the chemistry of the sub-thermocline waters that are ultimately upwelled in the subpolar gyre. The results demonstrate the influence of Southern Ocean winds on the North Atlantic carbon sink and show that the effect of Southern Ocean winds on atmospheric CO2 is likely twice as large as previously thought in past, present, and future climates

Agreement of CMIP5 simulated and observed ocean anthropogenic CO2 uptake

Previous studies found large biases between individual observational and model estimates of historical ocean anthropogenic carbon uptake. We show that the largest bias between the Coupled Model Intercomparison Project phase 5 (CMIP5) ensemble mean and between two observational estimates of ocean anthropogenic carbon is due to a difference in start date. After adjusting the CMIP5 and observational estimates to the 1791–1995 period, all three carbon uptake estimates agree to within 3 Pg of C, about 4% of the total. The CMIP5 ensemble mean spatial bias compared to the observations is generally smaller than the observational error, apart from a negative bias in the Southern Ocean and a positive bias in the Southern Indian and Pacific Oceans compensating each other in the global mean. This dipole pattern is likely due to an equatorward and weak bias in the position of Southern Hemisphere westerlies and lack of mode and intermediate water ventilation

2 2009 Expérience pilote PIT : mise en œuvre d’équipes infirmières dans 10 ambulances participant à l’aide médicale urgente en Belgique. Bilan au terme de la 2e année d’activité

peer reviewedL'article fait le bilan de l'expérience de moyens de secours à accompagnement infirmier sur base de deux ans de données d'intervention. Il conclut de l'analyse statistique que le temps d'intervention est réduit, que les actes posés sont comparables, et que la gestion de la douleur est améliorée

Importance of the Antarctic Slope Current in the Southern Ocean Response to Ice Sheet Melt and Wind Stress Change

We use two coupled climate models, GFDL-CM4 and GFDL-ESM4, to investigate the physical response of the Southern Ocean to changes in surface wind stress, Antarctic meltwater, and the combined forcing of the two in a pre-industrial control simulation. The meltwater cools the ocean surface in all regions except the Weddell Sea, where the wind stress warms the near-surface layer. The limited sensitivity of the Weddell Sea surface layer to the meltwater is due to the spatial distribution of the meltwater fluxes, regional bathymetry, and large-scale circulation patterns. The meltwater forcing dominates the Antarctic shelf response and the models yield strikingly different responses along West Antarctica. The disagreement is attributable to the mean-state representation and meltwater-driven acceleration of the Antarctic Slope Current (ASC). In CM4, the meltwater is efficiently trapped on the shelf by a well resolved, strong, and accelerating ASC which isolates the West Antarctic shelf from warm offshore waters, leading to strong subsurface cooling. In ESM4, a weaker and diffuse ASC allows more meltwater to escape to the open ocean, the West Antarctic shelf does not become isolated, and instead strong subsurface warming occurs. The CM4 results suggest a possible negative feedback mechanism that acts to limit future melting, while the ESM4 results suggest a possible positive feedback mechanism that acts to accelerate melt. Our results demonstrate the strong influence the ASC has on governing changes along the shelf, highlighting the importance of coupling interactive ice sheet models to ocean models that can resolve these dynamical processes. © 2022. American Geophysical Union. All Rights Reserved.6 month embargo; first published: 28 April 2022This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Simple Global Ocean Biogeochemistry With Light, Iron, Nutrients and Gas Version 2 (BLINGv2): Model Description and Simulation Characteristics in GFDL's CM4.0

Simulation of coupled carbon-climate requires representation of ocean carbon cycling, but the computational burden of simulating the dozens of prognostic tracers in state-of-the-art biogeochemistry ecosystem models can be prohibitive. We describe a six-tracer biogeochemistry module of steady-state phytoplankton and zooplankton dynamics in Biogeochemistry with Light, Iron, Nutrients and Gas (BLING version 2) with particular emphasis on enhancements relative to the previous version and evaluate its implementation in Geophysical Fluid Dynamics Laboratory's (GFDL) fourth-generation climate model (CM4.0) with 1/4 degrees ocean. Major geographical and vertical patterns in chlorophyll, phosphorus, alkalinity, inorganic and organic carbon, and oxygen are well represented. Major biases in BLINGv2 include overly intensified production in high-productivity regions at the expense of productivity in the oligotrophic oceans, overly zonal structure in tropical phosphorus, and intensified hypoxia in the eastern ocean basins as is typical in climate models. Overall, while BLINGv2 structural limitations prevent sophisticated application to plankton physiology, ecology, or biodiversity, its ability to represent major organic, inorganic, and solubility pumps makes it suitable for many coupled carbon-climate and biogeochemistry studies including eddy interactions in the ocean interior. We further overview the biogeochemistry and circulation mechanisms that shape carbon uptake over the historical period. As an initial analysis of model historical and idealized response, we show that CM4.0 takes up slightly more anthropogenic carbon than previous models in part due to enhanced ventilation in the absence of an eddy parameterization. The CM4.0 biogeochemistry response to CO2 doubling highlights a mix of large declines and moderate increases consistent with previous models.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]