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Marine life on Earth is known back to the Archean Eon, when life on land is assumed to have been less pervasive than now. Precambrian life on land can now be tested with stable isotopes because living soil CO2 is isotopically distinct for both carbon and oxygen from both marine and volcanic CO2. Our novel compilation of previously published oxygen and carbon isotopic compositions of pedogenic and paleokarst carbonate can be compared with the coeval marine record. Long-term enrichment (to heavier isotopic composition) of oxygen, but no significant trend in carbon through time, long apparent from marine carbonate, is now demonstrated also for pedogenic and paleokarst carbonate. Oxygen isotopic enrichment is not due to changing global temperature or hypsometry, but to increased evapotranspiration and photosynthesis on larger continents. Differences in isotopic composition between land and sea have increased in an episodic fashion, peaking at times of major evolutionary innovations for life on land, and also at times of ice ages. The δ13C and δ18O divergences between land and sea correspond to terrestrial productivity spikes including evolution of Neoproterozoic (635 Ma) lichens, middle Ordovician (470 Ma) non-vascular land plants, middle Devonian (385 Ma) forests, early Cretaceous (125 Ma) angiosperms, and middle Miocene (20 Ma) sod grasslands. [ABSTRACT FROM AUTHOR]

Aim: To determine the degree to which assemblages of planktonic foraminifera track thermal conditions. Location: The world's oceans. Time Period: The last 700,000 years of glacial–interglacial cycles. Major Taxa Studied: Planktonic foraminifera. Methods: We investigate assemblage dynamics in planktonic foraminifera in response to temperature changes using a global dataset of Quaternary planktonic foraminifera, together with a coupled Atmosphere–Ocean General Circulation Model (AOGCM) at 8000‐year resolution. We use 'thermal deviance' to assess assemblage responses to climate change, defined as the difference between the temperature at a given location and the bio‐indicated temperature (i.e., the abundance‐weighted average of estimated temperature optima for the species present). Results: Assemblages generally tracked annual mean temperature changes through compositional turnover, but thermal deviances are evident under certain conditions. The coldest‐adapted species persisted in polar regions during warming but were not joined by additional immigrants, resulting in minimal assemblage turnover. The warmest‐adapted species persisted in equatorial regions during cooling with similarly minimal assemblage change. Assemblages at mid‐latitudes mostly tracked temperature cooling and warming. Main Conclusions: Planktonic foraminiferal assemblages were generally able to track or endure temperature changes: as climate warmed or cooled, bio‐indicated temperature also became warmer or cooler, although to a variable degree. At polar sites under warming and at equatorial sites under cooling, the change in bio‐indicated temperature was less than, or even opposite to, what would be expected from estimated environmental change. Nevertheless, all studied species persisted across the study interval, regardless of thermal deviance—a result that highlights the resilience and inertia of planktonic foraminifera on an assemblage level to the last 700,000 years of climate change. [ABSTRACT FROM AUTHOR]

The rapid increase in carbon and other greenhouse gases is likely to change the regional and global temperature, and planning of these gases is needed. The present study focused on National Highway-16 of the Srikakulam district, which was upgraded from 4 to 6 lane standards to facilitate traffic. This study intended to compute the carbon sequestration and storage capacity of above and belowground biomass. This helps in the comparison and impact of the road project on flora and its carbon pool, from where future tree stock changes can be prepared. A total of 1930 plots were constructed of criss-crosses of equal size (2 × 100 m). All woody trees with dbh ≥ 30 cm were considered and their diameters were measured. A total of 29 tree species belonging to 13 families were identified; the quantity of macrobiotic carbon sequestered as a whole, i.e., above and below ground, was 768,890.29 tC and 199,911.48 tC, respectively. The mean sequestration rate of carbon as biomass above ground was 1.19 tC/tree, and that below ground was 0.31 tC/tree. The estimated average C-Stock per tree was 1.5 tC; however, the mean C-Stock per quadrate was 250.2 tC. [ABSTRACT FROM AUTHOR]

Warming temperatures are known to influence ectotherm life history and physiology. As climate change increases global temperatures, the consequences of direct and indirect effects of warming are becoming of high interest in biology. Warming temperatures could alter daily activity, change rates of food consumption, and influence allocation of energy, altering life history. Lizards are a taxon of concern regarding climate change, with documented thermal sensitivity in physiological performance and life history. The current study used a series of meta-analyses to examine how body temperature, food consumption, duration of daily activity, and growth rate influence lizards. The results indicated that warming temperatures increased food consumption but decreased growth rate. Meanwhile, increasing food consumption increases lizard growth rate. However, mechanistic studies are needed to determine the factors dictating identified trends, as the current approach is correlational. Overall, few data were available for the parameters of interest, with zero studies quantifying the influence of daily activity on food consumption. Restrictions in daily activity are a primary consideration with climate change models for lizards; however, empirical data quantifying the effects are lacking. The current study identified fruitful areas for future research, specifically on the effects of daily activity on energetics to understand indirect and direct effects of climate change. [ABSTRACT FROM AUTHOR]

Simple Summary: Maternally transmitted Wolbachia is one of the most common endosymbionts in many arthropods, influencing various aspects of host physiology, reproduction, and fitness. While recent studies on Wolbachia-Drosophila systems have revealed its influence on host thermal choice behavior, its broader impact on host thermal preference (Tp) in non-model insects remains poorly understood. The polyphagous leaf-miner fly, Liriomyza huidobrensis (Blanchard), one of the most notorious pests of vegetable and flowers globally, harbors a range of bacterial symbionts, with Wolbachia being especially prevalent. This study aims to explore the effects of Wolbachia on the thermal preference of the invasive leaf-miner L. huidobrensis. Understanding the potential roles of Wolbachia in host thermal behavior is crucial for elucidating the co-evolution of invasive species and their endosymbiont Wolbachia in the context of global climate change and temperature extremes, and may offer insight for the development of pest control strategies utilizing Wolbachia. Heritable endosymbiont Wolbachia is prevalent among arthropods, serving multiple functions for their hosts. However, the role of Wolbachia in mediating thermal preference selection remains largely unexplored. In this study, we utilized a custom-built thermal gradient to evaluate the thermal preference (Tp) of 1367 individuals of the invasive leaf-miner Liriomyza huidobrensis with or without Wolbachia wLhui from Yunnan and Xinjiang populations. Under meticulously controlled conditions and with a vast sample size, we found no significant difference in the mean Tp between wLhui-infected and uninfected leaf miners from either population when host age and sex were not considered. Furthermore, generalized linear model (GLM) analysis revealed no significant correlation between average Tp and age, sex, or Wolbachia infection, nor interactions among these factors, except in the Xinjiang population, where Tp was strongly associated with host age. Finally, we discuss the ecological implications of these findings and propose future research directions on Wolbachia-mediated host Tp in the leaf miner. Overall, our findings do not provide evidence that Wolbachia significantly affects the thermal preference of L. huidobrensis. Further studies across different systems are needed to investigate the complex interactions between Wolbachia and insect thermal behavior. [ABSTRACT FROM AUTHOR]

This study systematically reviews the integration of artificial intelligence (AI) and remote sensing technologies to address the issue of crop water stress caused by rising global temperatures and climate change; in particular, it evaluates the effectiveness of various non-destructive remote sensing platforms (RGB, thermal imaging, and hyperspectral imaging) and AI techniques (machine learning, deep learning, ensemble methods, GAN, and XAI) in monitoring and predicting crop water stress. The analysis focuses on variability in precipitation due to climate change and explores how these technologies can be strategically combined under data-limited conditions to enhance agricultural productivity. Furthermore, this study is expected to contribute to improving sustainable agricultural practices and mitigating the negative impacts of climate change on crop yield and quality. [ABSTRACT FROM AUTHOR]

It depends. The Intergovernmental Panel on Climate Change's (IPCC) Assessment Report Six (AR6) took a step toward ending so‐called 'model democracy' by discounting climate models that are too warm over the historical period (i.e., models that 'run hot') when making projections of global temperature change. However, the IPCC did not address whether this procedure is reliable for other quantities. Here, we explore the implications of weighting climate models according to their skill in reproducing historical global‐mean surface temperature using three other climate variables of interest: global average precipitation change, regional average temperature change, and regional average precipitation change. We find that the temperature‐based weighting scheme leads to an improved prediction of global average precipitation, though we show that this prediction could be overconfident. On regional scales, we find a heterogeneous pattern of error reduction in future regional precipitation. This stands in sharp contrast with the broad regional pattern of error reduction in future temperature projections, though we do find regions where error is not significantly reduced. Our results demonstrate that practitioners using weighted climate model ensembles for climate projections must take care when weighting by temperature alone, lest they produce unreliable climate projections that result from an inappropriate weighting procedure. Plain Language Summary: Climate model ensembles are widely used for risk assessment. However, a few of the most recent generation climate models 'run hot' in the historical period, widening the spread of future global warming. The Intergovernmental Panel on Climate Change's (IPCC) sixth assessment report presents a number of weighting schemes to address this 'hot model' problem, each of which discount models that are 'too hot' in the historical period. However, it is unclear if this procedure is reliable for other quantities of interest. Here we explore the impact of this procedure on global average precipitation change, regional temperature change, and regional precipitation change. We find that while this scheme improves the prediction of global precipitation change and generally improves the prediction of regional temperature, it does not broadly improve regional predictions of future precipitation change. We conclude that users of climate model output must be careful when applying a global temperature‐based weighting scheme in regional impact studies. Key Points: Using historical warming to weight climate models can improve global predictions of annual temperature change and precipitation changeUsing past warming to weight future climate projections has varied effects on regional error reduction depending on the metric of interestClimate model end‐users should use caution when applying a weighting scheme to avoid biased or overconfident assessments of climate impacts [ABSTRACT FROM AUTHOR]

Studies of the Last Interglacial (ca. 129 to 116 ka BP) provide an opportunity to study the impact of high‐latitude warm temperatures on the Earth system. To build an accurate spatio‐temporal picture of climate and environmental variability during the Last Interglacial, building robust chronologies, through which the patchwork of terrestrial, marine, and ice core archives can be correlated, is paramount. In this review, we briefly evaluate the most common approaches used to date climate and environmental archives from the Last Interglacial, as well as the chronostratigraphic tools available for direct correlation between sequences, with a focus on terrestrial archives. We then present a case study on the use of pollen biostratigraphy for correlating sequences in NW Europe, highlighting its strength as a local correlation tool, and the challenges this approach presents in comparing sequences to global records of climate and environmental change. A move towards consistently dated sequences will improve our understanding of environmental responses to Last Interglacial climate variability across different elements of the global climate system and the rates at which different elements of the climate system respond to changes in global temperatures. [ABSTRACT FROM AUTHOR]

When the Albanese government was elected, it was widely proclaimed that climate policy was back on track in Australia. Eight bleak years of Coalition denialism and intransigence had been punished [...]

ABSTRACT The increase in the frequency and intensity of droughts and heatwaves caused by climate change poses a major threat to biodiversity. In aquatic systems, sedentary species such as freshwater mussels are generally considered more vulnerable to changes in habitat conditions than mobile species such as fish. As mussels provide important ecosystem services, understanding the impacts of drought on freshwater mussels is of particular importance for the management of overall functioning of aquatic ecosystems. We used a comprehensive literature search to provide a systematic overview of direct and indirect effects of drought on freshwater mussels (Bivalvia: Unionida) and an evaluation of mitigation strategies. We found that drought studies were concentrated mostly in the USA, with a focus on the Unionidae family. Topics ranged from the physiological effects of high temperatures, emersion, and hypoxia/anoxia to behavioural and reproductive consequences of drought and the implications for biotic interactions and ecosystem services. Studies spanned all levels of biological organization, from individual responses to population‐ and community‐level impacts and ecosystem‐wide effects. We identified several knowledge gaps, including a paucity of trait‐based evaluation of drought consequences, limited understanding of thermal and desiccation tolerance at the species level, and the synergistic effects of multiple drought stressors on mussels. Although we found many studies provided suggestions concerning management of populations, habitat conditions, and anthropogenic water use, a systematic approach and testing of recommended mitigation strategies is largely lacking, creating challenges for managers aiming to conserve freshwater mussel communities and populations in light of climate change. [ABSTRACT FROM AUTHOR]

Climate change is altering the geographical distribution and abundance of species. Abundant genetic variation generally indicates a stronger adaptability and evolutionary potentiality, especially in case of sharply changing climates or environments. With the past global climate fluctuations, especially the climate oscillation since the Quaternary, the global temperature changes related to glaciation, many relict plant species have formed possible refugia in humid subtropical/warm temperate forests, thus retaining a high level of genetic diversity patterns. Based on the contraction and expansion of the geographical distribution of Taxus wallichiana Zucc. in the past driven by climate change, combined with the contemporary genetic diversity modeling, the distribution performance of Taxus wallichiana Zucc. in future climate change was predicted. The areas of highly suitable habitat will increase with climate change in the future. There were continuous and stable high suitable areas of T. wallichiana in the southeastern Tibet and northwestern Yunnan as long-term stable climate refugia. We made the genetic landscape surface of T. wallichiana complex and discovered geographical barriers against gene flow. Genetic barriers spatially isolated the center of genetic diversity into three regions: west (east Himalaya), middle (Yunnan plateau, Sichuan basin, Shennongjia, and the junction of Guizhou and Guangxi provinces), and east (Mt. Huangshan and Fujian). Southern Tibet was isolated from other populations. The central and western Yunnan, the Sichuan basin, and surrounding mountains were isolated from the southern China populations. We found that the positive correlationships between the present species genetic diversity and suitability index during LGM, MH, and 2070. This infers that T. wallichiana has provisioned certain genetic diversity and has strong evolutionary potential under conditions of climate change. [ABSTRACT FROM AUTHOR]

Biomass feedstocks are growing in importance due to their ability to serve as a renewable alternative to fossil fuels for large scale energy generation, with bioenergy projected to be a growing part of the UK's energy mix. Combined with technologies such as carbon capture and storage, sustainable bioenergy has the potential to produce negative emissions with including counterbalancing residual emissions. This paper presents a systematic review of the sustainability impacts of wood biomass (forestry/SRC) and Miscanthus, which are grown as energy fuels, comparing the three key indicators of sustainability: soil organic carbon sequestration rates, biodiversity, and water use efficiency (WUE). Analysis has shown significant influence from primary soil composition (p < 0.001) and previous land use (p < 0.001) on soil organic carbon sequestration rates following conversion to biomass feedstock production. Conversion from arable to forestry can have positive rates of sequestration of 1.4 ± 0.3 Mg C ha−1 year−1 on mineral soils, while similar conversions on a highly organic soils can lead to losses of −25 Mg C ha−1 year−1. This indicates a strong need for careful site selection for future forestry plantations. Miscanthus showed no preference under mineral or organic soils for carbon sequestration rate. Biodiversity at different trophic scales is impacted differently by biomass feedstock production. No significant impact on invertebrates was demonstrated between feedstocks but there is a significant difference between crops (p < 0.001) for vertebrates at higher trophic levels. A limited dataset was collected for WUE from the review, but analysis showed comparable WUE rates for Miscanthus and short rotation coppice, while forestry had significantly lower (p < 0.001) WUE. With global temperatures increasing and changes to climate, water stress is likely to increase. WUE will play an important role in the considerations dfor long term biomass feedstock planning and sourcing. [ABSTRACT FROM AUTHOR]

In piping systems, flexible joints can mean connections or elements designed to absorb movement or pressure that can occur in pipes, such as temperature changes or ground movements. This function can help prevent cracks or damage to the pipe system. The use of flexible joints in oil piping aims to maintain the integrity of the pipe system, prevent leaks, and reduce pressure that can damage pipes or other devices. This is critical especially in the oil and gas industry environment which has dynamic operational conditions. The purpose of this study was to find out how to maintain flexible joints and handle damage that occurs to flexible joints in storage tanks at PT X. The results of the study showed that damage of Flexible Joints occurred due to the installation of Motor Operated Valves (MOVs) that did not meet standards and Pressure Safety Valves (PSVs) was not calibrated everyday that experienced corrosion and broken springs due to lack of maintenance. Therefore, routine inspections were needed to prevent damage to the Pressure Safety Valve. [ABSTRACT FROM AUTHOR]

Sea level rise (SLR) is a crucial indicator of climate change, primarily driven by greenhouse gas emissions and the subsequent increase in global temperatures. The impact of SLR, however, varies regionally due to factors such as ocean bathymetry, resulting in distinct shifts across different areas compared to the global average. Understanding the complex factors influencing SLR across diverse spatial scales, along with the associated uncertainties, is essential. This study focuses on the East Coast of the United States and Gulf of Mexico, utilizing historical SLR data from 1993 to 2023. To forecast SLR trends from 2024 to 2103, a weighted ensemble model comprising SARIMAX, LSTM, and exponential smoothing models was employed. Additionally, using historical greenhouse gas data, an ensemble of LSTM models was used to predict real-time SLR values, achieving a testing loss of 0.005. Furthermore, conductance and dissolved oxygen (DO) values were assessed for the entire forecasting period, leveraging forecasted SLR trends to evaluate the impacts on marine life, agriculture, and infrastructure. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) emissions affect local temperature; quantifying that local response is important for learning about the earth system, the impacts of mitigation, and adaptation needs. We assume the climate system can be represented as a time‐dependent linear system, diagnosing Green's Functions for the spatial temperature response to CO2 emissions based on CMIP6 earth system models. This allows us to emulate the linear component of the temperature response to CO2. This approach is sufficient to capture the spatial temperature response of CMIP6 experiments within one standard deviation of the multimodel spread across most regions, though accuracy is lower in the Southern Ocean and the Arctic. Our approach reveals where nonlinear feedbacks are important in current CMIP6 models, and where the local system response is well represented by a time‐dependent linear differential operator. It incorporates emissions path dependency and may be useful for evaluating large ensembles of emission scenarios. Plain Language Summary: Carbon dioxide (CO2) emissions impact surface temperature. It is well established that the global mean temperature change is proportional to the cumulative emissions of CO2. This has led to the creation of carbon budgets to reach temperature goals. We test this relationship at the spatio‐temporal scale, quantifying a simple approach that estimates the local temperature response to CO2 emissions alone. We use an approach built from the Climate Model Intercomparison Project Phase 6 (CMIP6) Earth System Models, based on the concept that an additional unit of CO2 can be scaled for larger emissions and summed over time to estimate cumulative impacts. We evaluate this with additional CMIP6 experiments, showing that this approach captures the temperature response in most locations with lower accuracy in the Arctic and Southern Ocean. This type of approach may be useful to evaluate many policy scenarios and to better understand earth system processes that are represented in the models, as it takes around one second to quantify 90 years' worth of temperature change on a local computer, while Earth System Models can require weeks of runtime on supercomputers. Key Points: With a Green's Function approach, we emulate the linear component of the spatially resolved temperature response to CO2 emissionsWe reproduce the temperature response well within multi‐model uncertainty except in the Arctic and Southern OceanThis approach allows expedient quantification of the spatial and temporal temperature response to varying CO2 emissions pathways [ABSTRACT FROM AUTHOR]

East Asia experienced complex climatic changes during the Eocene. Due to the lack of a high‐precision time framework covering the Eocene, the characteristics of sedimentary and climate evolution in this period remain unclear. The Jianghan Basin (Central China) developed an Eocene continental succession, which is composed of lower red beds and upper salt‐lake deposits exhibiting clear sedimentary rhythms, making these strata an ideal target for astronomical cycle analysis. Based on the established floating astronomical timescale, the lower red beds in the basin formed during the early–middle Eocene and were dominated by eccentricity cycles. The upper salt‐lake deposits formed during the middle–late Eocene and recorded obliquity cycles. The change in facies indicates that the climate transitioned from continuously arid to less arid with periodic relative wetness, which was forced by orbital cycles. Significant obliquity signals recorded by salt rhythmites responded to Eocene global temperature changes and Tibetan region uplift, which can be important markers of a monsoon‐like climate. Comparing the sedimentary and climatic characteristics of other Eocene lake basins in East Asia, the extension of the Eocene East Asian monsoon may have initiated during ca 43.6 to 40.0 Ma. This study provides a new perspective for understanding the early evolution of the East Asian monsoon. [ABSTRACT FROM AUTHOR]

Under partial shading conditions (PSCs), photovoltaic (PV) systems exhibit non-uniform P-V characteristic curves with multiple local maximum power points (LMPP). Consequently, conventional maximum power point tracking (MPPT) algorithms often fail to accurately track the global maximum power point (GMPP), becoming trapped at local maxima and resulting in power loss. This paper introduces a novel MPPT controller based on the weighted mean of vectors (INFO) optimization algorithm to address these challenges. The INFO algorithm integrates three key operators: updated law, vector combination, and local search, offering advantages such as rapid convergence, high efficiency, and optimized power extraction under both PSCs and temperature changes (TCs). To validate the effectiveness of the INFO algorithm under PSCs and TCs, a partial shading platform featuring three PV modules with identical characteristics but varying radiation levels is utilized. Simulation studies compare the INFO algorithm against traditional perturb and observe (P&O), particle swarm optimization (PSO), and overall distribution particle swarm optimization (OD-PSO) algorithms in terms of MPPT performance. Results demonstrate that the INFO algorithm achieves a 60% reduction in tracking time and a 0.02% increase in MPPT controller efficiency compared to these methods. Overall, the proposed INFO algorithm achieves a balanced approach between exploration and exploitation stages, enhancing robustness, efficiency, and reducing tracking time in MPPT applications. [ABSTRACT FROM AUTHOR]

The Southern Ocean connects the Pacific, Atlantic, and Indian Oceans, serving as a key hub for the global overturning circulation. The climate of the Southern Ocean is closely linked to the low-latitude equatorial Pacific, as well as the highlatitude regions of the North Atlantic, making it an important component of the global climate system. Due to the interactions of various processes such as atmospheric, oceanic, and ice cover, the Southern Ocean exhibits a complex and variable sea surface temperature structure. Satellite observations indicate that since 1980, the sea surface temperature of the Southern Ocean has been cooling, contrary to the global warming trend. However, due to the relatively short length of satellite observations, the specific mechanisms are not yet clear. Here, we used the EOF method to analyze sea surface temperature data since 1870 (HadISST1 and ERSSTV5), with three main separated modes explaining over 70% of the sea temperature variability. Among them, the first mode shows widespread positive sea surface temperature anomalies in the Southern Ocean, with a time series change consistent with global temperature anomalies, representing a mode of global warming. The second mode corresponds to the Atlantic Multidecadal Oscillation (AMO) but with a lag of approximately 4 years. The third mode is consistent with the variability of the El Niño-Southern Oscillation (ENSO). Furthermore, our study indicates that despite the ongoing global warming since 1980, the negative phase of AMO and positive phase of ENSO may counteract the effects of global warming, leading to an overall cooling trend in the sea surface temperature of the Southern Ocean. [ABSTRACT FROM AUTHOR]

The main consequence of climate change on temperature is global warming. Over the past century, worldwide temperature has increased, rising by about 0.14 degrees Fahrenheit every year. Rising temperature negatively affects morphology, physiology, and yield of crops. Over the last 5 years, agriculture production in Pakistan affected due to temperature increase. Pakistan is an agriculture based developing country. About 2.2% GDP of Pakistan depends on wheat crop which is 1st major cereal crop and ranked as staple food. Nutritionally it provides proteins, dietary fibers, carbohydrates, calcium, and other important compounds but because of the harmful effects of a high temperature, yield of wheat crop in Pakistan has reduced to lowest levels in the last few years. Heat stress affects wheat plants by reducing growth, raised reactive oxygen species (ROS) production, denature cell membranes, and enzymes activity, decreasing photosynthetic activity and disturbing respiration processes. Improving wheat crop productivity is urgently needed to feed the rapidly growing population. Several techniques like Quantitative Trait Locus mapping, omics techniques, and application of nutrients have been used in the past to mitigate high temperature effect on wheat and other different crop plants. This review critically analyzes the response of wheat towards heat stress and its impacts on wheat crop as well as provides critical information on advanced strategies and techniques for the mitigation of heat stress. [ABSTRACT FROM AUTHOR]

In light of climate change and increasing global temperatures, it is important to equally prioritize the study of inorganic carbon dynamics in calcareous soils within temperate ecosystems, as has been done for arid or semiarid environments. A significant area of vineyards in Germany is established on calcareous soils. However, the potential influence of inorganic carbon on CO2 emissions in these vineyards has not been sufficiently explored when evaluating the carbon footprint of management practices in relation to carbon storage. Therefore, we aimed to differentiate between organic and inorganic sources of CO2 emissions from six vineyard soils located in the southwest of Germany that had previously received organic soil amendments (OA). Inorganic carbon content varied between 8 and 55 g kg−1 across different sites, with variations observed in the inorganic‐to‐organic carbon ratio. Soil samples were incubated under standard laboratory conditions for 48 h, and the source of emitted CO2 was determined using a two‐end‐member mixing model. The contribution of inorganic carbon to CO2 emissions was influenced by the quantity of inorganic carbon, with an increase in contribution with increasing inorganic‐to‐organic carbon ratio. On average, abiotic sources accounted for 5% to 40% of the emitted CO2 at the different sites, with one site showing no significant contribution of inorganic carbon. CO2 production from inorganic carbon was higher in the subsoil compared with the topsoil, likely related to the higher content of inorganic carbon in the subsoil. Notably, there was no discernible influence of OA on carbonate dissolution. This study emphasizes the significance of considering abiotic sources of CO2 emissions in addition to soil respiration in calcareous soils and highlights the need for further investigation to apply these findings at the field scale. [ABSTRACT FROM AUTHOR]

The goal of this effort is to determine the interaction among the heating and cooling processes in order to understand how solids behave when subjected to temperature changes. In this instance, the temperature, displacement, and stress relations are determined analytically and numerically while a thin annular disc is subjected to both the heating and cooling processes. The ability of a material to withstand stress is essential for the design of diverse mechanical structures that aim to enhance performance, durability, characteristics, and strength. This ability is demonstrated in many physical processes where the material structure crosses over into heating and cooling processes. Furthermore, memory derivatives used in the modelling of heat transfer equations more accurately depict the memory behaviour of an imagined disc and explain its physical significance. [ABSTRACT FROM AUTHOR]

Background: The primary issue facing the Earth in this century is the increase in global temperatures and changes in climate variables due to industrialization and rising greenhouse gas emissions. Therefore, it is crucial to investigate temperature trends and climatic changes on both global and regional scales. While several general circulation models have been developed to predict future climate states, different and new methods have been invented to use the output of these models on regional and local scales due to the lack of optimal use of the output of these models caused by the limitation in spatial resolution on the local scale. The Gedarchay watershed is significant for its Gedarchay river basin and groundwater resources-especially in agriculture-, hence it has been the focus of various studies. However, no research has yet studied the impacts of climate change under SSP scenarios of the 6th report, which incorporate socioeconomic factors. Thus, this study aims to analyze future changes in climate variables for the Gedarchay Naghadeh watershed under the RCP emission scenarios of the fifth report (CMIP5) and the SSP scenarios of the sixth report (CMIP6), integrating greenhouse gas emissions and socioeconomic activities. The findings could significantly inform future water resource policymaking and planning. Methods: This research utilized the SDSM microscale exponential model to analyze climatic variable changes in the Gedarchay Naghadeh watershed in northwestern Iran. The model's effectiveness was first assessed for climate variables, followed by predictions extending to 2100. Calibration and recalibration were performed using observational data from the Mahabad Synoptic Station and NCEP data. The model's performance was evaluated using correlation coefficients, mean absolute error, and mean square error. After confirming the model's reliability, outputs from the CanESM2 and CanESM5 models were studied for the periods 2031-2050 and 2081-2100 under the RCP 2.6, 4.5, 8.5 and SSP1-2.6, 2-4.5, 5-8.5 scenarios by the microscale SDSM statistical model. Results: The model's evaluation and recalibration were done using NCEP, CanESM2, and CanESM5 data to forecast and compare precipitation, maximum, and minimum temperatures for the Mahabad station across two periods 2031-2050 and 2081-2100, against a baseline. The accuracy of the SDSM model was assessed using average absolute error statistics, and the errors for precipitation, maximum, and minimum temperatures were 1.645, 0.029, and 0.031, respectively, with CanESM2; their values were 0.73, 1.10, and 1.89. Correlation coefficients were also calculated, yielding 0.998, 0.999, and 0.999 for the CanESM2 model and 0.999, 0.993, and 0.971 for the CanESM5 model. The mean squared errors were 2.240, 0.043, and 0.045 for CanESM2, and 0.89, 1.49, and 2.07 for CanESM5. Results indicate that the average maximum temperature is projected to rise by 0.93 °C from 2031 to 2050 under the RCP scenario but it remains stable from 2081 to 2100. Increases of 1.24 °C in 2031-2050 and 0.35 °C in 2081-2100 were anticipated under the SSP scenario. The average minimum temperature increases for the RCP scenario were 0.27 and 0.28 °C for the respective periods, and 0.46 and 0.43 °C for the SSP scenario. Rainfall is projected to rise by 0.59 and 0.38 mm in the RCP scenario during the two periods, compared to increases of 2.15 and 1.64 mm, respectively, under the SSP scenario. Conclusion: The evaluation of the SDSM model's accuracy in predicting precipitation, maximum temperature, and minimum temperature using R, MAE, and RMSE statistics indicates a strong alignment between predicted values and the base period. Results show an increase in precipitation and minimum temperature in both the near and distant futures, with a rise in maximum temperature in the near future and stability in the distant future. Given the significance of climate change and its impacts on agriculture, the environment, and water resources, it is essential for managers and planners to implement effective solutions. These include altering cultivation patterns, using drought-resistant crops, establishing early warning systems, training farmers in climate adaptation methods, and promoting renewable energy to mitigate climate change effects. [ABSTRACT FROM AUTHOR]

Iron oxide assemblages are central to many pursuits, ranging from Mars exploration to environmental remediation. Oxides and oxyhydroxides of iron both carry the special properties of color and magnetism. In this paper, we use visible-light spectroscopy and rock magnetic data collected at varying temperatures (~77–973 K) to analyze the concentrations and identities of iron oxides found in natural hematite-dominated samples that were obtained from a scientific drill core of Late Triassic red beds in the American Southwest. Our results suggest that hematite colorization of Earth materials varies from red to blue/purple as crystal size increases. Second-derivative analysis of the collected visible-light spectra allows this variation to be measured through the characteristic wavelength band position. Magnetic coercivity data indicate "hardness" differences that also may suggest smaller grain sizes are associated with redder colors. Yellowish maghemite and goethite have overlapping characteristic wavelength band positions that make it challenging to distinguish their contributions to mixed assemblages from visible-light data alone. Remanent magnetizations acquired at ~77 K and room temperature suggest the presence of hematite and a low-coercivity phase that may be maghemite and/or oxidized magnetite. However, we interpret this phase as maghemite in order to explain the changes in iron oxide concentrations indicated by visible-light intensities near ~425 nm and because the thermal demagnetization data suggest that goethite is absent from the samples. Future research that increases the resolution of hematite, maghemite, and goethite detection in experimental and natural samples will provide opportunities to refine the study of past climates and constrain soil iron availability under future changes in global moisture and temperature. Multimethod datasets improve understanding of environmental conditions that cause iron oxides assemblages to shift in phase dominance, grain size, and crystallinity. [ABSTRACT FROM AUTHOR]

While some degree of competition is present in many authoritarian regimes, the implications of such controlled competition on international issues have not received much consideration, including towards international environmental accords. We attempt to rectify this through a framework where we focus on internal political competition in a hybrid, nondemocratic system where national elections are held regularly. Specifically, we argue that the presence of multiple actors competing in elections in nondemocratic settings results in them assuming positions on various issues, justifying their positions, and attempting to mobilize their supporters with considerable implications for international environmental policies. We display our argument in the context of Iranian debates on the ratification of the Paris Climate Accords. Our findings demonstrate that the competing Iranian sides rely on different justifications for their environmental positions, resulting in extensive (negative) competitions of rhetoric where the international dimension emerges as an important feature in the internal competition. Overall, we show that political competition within non-democracies is likely to add to the complexity of international (environmental) negotiations and cooperation. Keywords: internatonal negotatons on climate change; competng narratves and electons in authoritarian regimes; politcal factons; environment and sanctons; regime survival, Introduction The Paris Climate Change Agreement, a legally binding international treaty that sets goals for temperature increases, was adopted by 196 parties at the United Nations (UN) Climate Change Conference [...]

Honorary Member Mary Glackin Honorary Member John Toohey-Morales Honorary Member Andrea Celeste Saulo The Carl-Gustaf Rossby Research Medal Benjamin Santer For outstanding contributions to comprehending how climate change affects atmospheric [...]

Objective To identify evidence-based interventions that reduce greenhouse gas emissions in health-care systems in low-and middleincome countries and explore potential synergies from these interventions that aid climate change adaptation while mitigating emissions. Methods We systematically searched 11 electronic databases for articles published between 1990 and March 2023. We assessed risk of bias in each article and graded the quality of evidence across interventions in health-care operations, energy and supply chains. Findings After screening 25 570 unique records, we included 22 studies published between 2000 and 2022 from 11 countries across six World Health Organization regions. Identified articles reported on interventions spanning six different sources of emissions, namely energy, waste, heating and cooling, operations and logistics, building design and anaesthetic gases; all of which demonstrated potential for significant greenhouse gas emission reductions, cost savings and positive health impacts. The overall quality of evidence is low because of wide variation in greenhouse gas emissions measuring and reporting. Conclusion There are opportunities to reduce the greenhouse gas emissions from health-care systems in low- and middle- income countries, but gaps in evidence were identified across sources of emissions, such as the supply chain, as well as a lack of consideration of interactions with adaptation goals. As efforts to mitigate greenhouse gas intensify, rigorous monitoring, evaluation and reporting of these efforts are needed. Such actions will contribute to a strong evidence base that can inform policy-makers across contexts. Objectif Identifier les interventions fondees sur des donnees factuelles qui visent a reduire les gaz a effet de serre emanant des systemes de soins de sante dans les pays a revenu faible et intermediaire, mais aussi explorer d'eventuel les synergies liees a ces interventions et susceptibles de contribuer a une meilleure adaptation au changement climatique tout en reduisant les emissions. Methodes Nous avons procede a une analyse systematique de 11 bases de donnees electroniques, a la recherche d'articles publies entre 1990 et mars 2023. Pour chaque article, nous avons determine le risque de biais et evalue la qualite des donnees relatives aux interventions dans les unites de soins de sante, l'energie et les cha nes d'approvisionnement. Resultats Apres avoir examine 25 570 documents uniques, nous avons conserve 22 etudes publiees entre 2000 et 2022, issues de 11 pays appartenant a six regions de l'Organisation mondiale de la Sante. Les articles retenus mentionnaient des interventions couvrant six sources d'emissions differentes, a savoir l'energie, les dechets, le chauffage et la climatisation, les operations et services logistiques, la conception des b timents, ainsi que les gaz anesthesiques; toutes ont revele un potentiel en matiere de reduction des emissions de gaz a effet de serre, de realisation d'economies et d'impact positif sur la sante. Globalement, les donnees sont de pietre qualite en raison des variations des mesures et rapports concernant les emissions de gaz a effet de serre. Conclusion Il existe plusieurs moyens de reduire les emissions de gaz a effet de serre provenant des systemes de soins de sante dans les pays a revenu faible et intermediaire. Cependant, les preuves sur les sources d'emissions manquent, notamment au niveau de la cha ne d'approvisionnement, et les interactions a des fins d'adaptation ne sont que rarement prises en compte. Alors que les efforts visant a reduire ces emissions se multiplient, il est imperatif de les surveiller, de les evaluer et d'etablir des rapports rigoureux. De telles actions contribueront a mieux etayer les donnees afin d'orienter les responsables politiques en fonction du contexte. Objetivo Identificar intervenciones basadas en evidencias que reduzcan las emisiones de gases de efecto invernadero en los sistemas sanitarios de los paises de ingresos bajos y medios y explorar las posibles sinergias de estas intervenciones que ayuden a adaptarse al cambio climatico mientras se mitigan las emisiones. Metodos Se realizaron busquedas sistematicas en 11 bases de datos electronicas de articulos publicados entre 1990 y marzo de 2023. Se evaluo el riesgo de sesgo en cada articulo y se clasifico la calidad de las pruebas en las intervenciones relacionadas con las operaciones sanitarias, la energia y las cadenas de suministro. Resultados Tras examinar 25 570 registros unicos, se incluyeron 22 estudios publicados entre 2000 y 2022 de 11 paises de seis regiones de la Organizacion Mundial de la Salud. Los articulos identificados informaron sobre intervenciones que abarcaban seis fuentes diferentes de emisiones: energia, residuos, calefaccion y refrigeracion, operaciones y logistica, diseno de edificios y gases anestesicos; todos ellos demostraron potencial para reducciones significativas de las emisiones de gases de efecto invernadero, ahorro de costes e impactos positivos en la salud. La calidad general de las evidencias es baja debido a la gran variacion en la medicion y la notificacion de las emisiones de gases de efecto invernadero. Conclusion Existen oportunidades para reducir las emisiones de gases de efecto invernadero de los sistemas de atencion sanitaria en los paises de ingresos bajos y medios, pero se han detectado deficiencias en las evidencias de las diferentes fuentes de emisiones, como la cadena de suministro, asi como una falta de consideracion de las interacciones con los objetivos de adaptacion. A medida que se intensifican los esfuerzos para mitigar los gases de efecto invernadero, es necesario realizar un seguimiento, una evaluacion y una notificacion rigurosos de estos esfuerzos. Estas medidas contribuiran a crear una base de evidencias solida que pueda informar a los responsables de formular las politicas en todos los contextos., Introduction In the absence of actions to rapidly reduce global greenhouse gas emissions, climate change is predicted to be the biggest threat to human health in the 21st century. Direct [...]

The 36th meeting of the International Task Force for Disease Eradication (ITFDE) (1) was convened in a hybrid (virtual and in-person) format at the Carter Center in Atlanta (GA), USA, [...]

Drawing on ecological economics, post-development studies, and political ecology, this paper argues that sustainable development notions have run their course within sustainability marketing debates and proposes degrowth as an alternative framework to steer disciplinary debates in new directions. We chart unexplored territory, offering sustainability marketing scholars tools to navigate degrowth-minded policies, transformative frameworks, and business models. In doing so, our work contributes to existing sustainability marketing debates in three ways: first, we respond to the paucity of studies engaging with the political economy of sustainability marketing. Second, we make visible the tensions and contradictions that arise as marketers seek to reconcile imperatives of economic growth and sustainability. Finally, we foreground degrowth as an emerging sustainability proposition, with potential for inspiring the radical set of transformations required to avert catastrophic climate change and keep global temperatures well below +2°C (relative to pre-industrial levels), as pledged in the Paris Agreement. [ABSTRACT FROM AUTHOR]

In investigating global patterns of biodiversity through deep time, many large-scale drivers of diversification have been proposed, both biotic and abiotic. However, few robust conclusions about these hypothesized effectors or their roles have been drawn. Here, we use a linear stochastic differential equation (SDE) framework to test for the presence of underlying drivers of diversification patterns before examining specific hypothesized drivers. Using a global dataset of observations of skeletonized marine fossils, we infer origination, extinction and sampling rates (collectively called fossil time series) throughout the Phanerozoic using a capture–mark–recapture approach. Using linear SDEs, we then compare models including and excluding hidden (i.e. unmeasured) drivers of these fossil time series. We find evidence of large-scale underlying drivers of marine Phanerozoic diversification rates and present quantitative characterizations of these. We then test whether changing global temperature, sea-level, marine sediment area or continental fragmentation could act as drivers of the fossil time series. We show that it is unlikely any of these four abiotic factors are the hidden drivers we identified, though there is evidence for correlative links between sediment area and origination/extinction rates. Our characterization of the hidden drivers of Phanerozoic diversification and sampling will aid in the search for their ultimate identities. [ABSTRACT FROM AUTHOR]

There are many uncertainties in future climate, including how the Earth may react to different types of radiative forcing, such as CO2, aerosols, and even geoengineered changes in the amount of sunlight absorbed by Earth's surface. Here, we analyze model simulations where the climate system is subjected to an abrupt change of the solar constant by ±4%, and where the atmospheric CO2 concentration is abruptly changed to quadruple and half its preindustrial value. Using these experiments, we examine how clouds respond to changes in solar forcing, compared to CO2, and feedback on global surface temperature. The total cloud response can be decomposed into those responses driven by changes in global surface temperature, called the temperature mediated cloud feedbacks, and responses driven directly by the forcing that are independent of the global surface temperature. In this paper, we study the temperature mediated cloud changes to answer two primary questions: (a) How do temperature mediated cloud feedbacks differ in response to abrupt changes in CO2 and solar forcing? And (b) Are there symmetrical (equal and opposite) temperature mediated cloud feedbacks during global warming and global cooling? We find that temperature mediated cloud feedbacks are similar in response to increasing solar and increasing CO2 forcing, and we provide a short review of recent literature regarding the physical mechanisms responsible for these feedbacks. We also find that cloud responses to warming and cooling are not symmetric, due largely to non‐linearity introduced by phase changes in mid‐to‐high latitude low clouds and sea ice loss/formation. Plain Language Summary: As the global mean temperature changes, there are changes in cloud amount, location, and thickness, which can all impact the radiative balance of the Earth. Cloud changes driven directly by global temperature change are called temperature mediated cloud feedbacks. In this paper, we study the temperature mediated cloud feedbacks that occur in model simulations where the amount of sunlight incident upon the Earth is increased or decreased abruptly, and then held constant for 150 years. We compare the cloud changes in these experiments with experiments where the CO2 concentration is similarly increased or decreased abruptly and held constant for 150 years. In doing so we find that the temperature mediated cloud feedbacks following abrupt changes in solar radiation are characteristically similar to those occurring following CO2 increase. There are however substantial differences in the temperature mediated cloud feedbacks that occur while the climate is warming versus cooling. Key Points: The temperature mediated cloud changes and feedbacks incurred by changes in solar and CO2 forcing are similarOptical depth changes at high latitudes produce substantial differences in cloud feedbacks in cooling and warming experimentsLikewise, tropical circulations respond differently in models to cooling and warming, with a stronger change in the Walker circulation in warming experiments [ABSTRACT FROM AUTHOR]

The impact of changes in global temperatures and precipitation on climate distribution remains unclear. Taking the annual global average temperatures and precipitation as the origin, this study determined the climate distribution with the distances of temperature and precipitation from their global averages as the X and Y axes. The results showed that during 1980–2019, the global temperature distribution converged toward the mean (convergence), while the precipitation distribution moved away from the mean (divergence). The combined effects of both led to a convergence in the global climate distribution. During 2025–2100, significant climate convergence is observed under two emission scenarios (SSP245 and SSP585). However, the climate convergence and the area of change in climate type remains insignificant only under SSP126, suggesting that the diversity of the global climate pattern can be maintained under a sustainable emission pathway (SSP126), whereas high emission pathways will lead to greater uniformity in global climate. Plain Language Summary: Global average temperatures and precipitation have increased significantly over recent decades. However, the distribution of affected areas remains unclear in comparison to the global mean. Taking annual temperature and precipitation averages as a reference point, this study measured temperature and precipitation anomalies from the global mean on the X and Y axes. The Euclidean distance of each grid cell represents its deviation (anomaly) from the global climate mean. These distances are termed the degree of deviation of temperature, precipitation, and climate from the global mean for each raster. The results reveal a discernible homogenization trend regarding the distribution of global climate. Among three distinct climate scenarios, climate diversity is effectively preserved under the low‐emission model (SSP126), whereas global climate distribution exhibits a substantial convergence toward the annual mean under the high‐emission models (SSP245 and SSP585). Key Points: Against the backdrop of global warming, the climate pattern is shifting toward convergenceTemperature is the primary driver behind climate convergence, while precipitation plays a central role in climate diversityLow‐level emissions are conducive to preserving the diversity of future global climate distribution [ABSTRACT FROM AUTHOR]

Maintaining high-quality welded connections is crucial in many industries. One of the challenges is assessing the mechanical properties of a joint during its production phase. Currently, in industrial practice, this occurs through NDT (non-destructive testing) conducted after the production process. This article proposes the use of a virtual sensor, which, based on temperature distributions observed on the joint surface during the welding process, allows for the determination of hardness distribution across the cross-section of a joint. Welding trials were conducted with temperature recording, hardness measurements were taken, and then, neural networks with different hyperparameters were tested and evaluated. As a basis for developing a virtual sensor, LSTM networks were utilized, which can be applied to time series prediction, as in the analyzed case of hardness value sequences across the cross-section of a welded joint. Through the analysis of the obtained results, it was determined that the developed virtual sensor can be applied to predict global temperature changes in the weld area, in terms of both its value and geometry changes, with the mean average error being less than 20 HV (mean for model ~35 HV). However, in its current form, predicting local hardness disturbances resulting from process instabilities and defects is not feasible. [ABSTRACT FROM AUTHOR]

Coastal regions have experienced economic losses from natural disasters due to rising global temperatures and climate change. Accurate and timely weather information may reduce people's sensitivity to the risks associated with climate change. In this context, the imperative for accurate weather forecasting is paramount as a proactive measure to mitigate the adverse consequences. Integrating weather forecasting into a user-friendly app or website can provide a vital communication channel, ensuring widespread awareness and preparedness by promptly disseminating information about imminent weather-related risks. The study aims to employ a two-layer stacking ensemble method customized for daily weather prediction, encompassing temperature, relative humidity, and sealevel pressure simultaneously through multioutput regression. The first layer of the model implemented a stacked feature scaling ensemble approach for the task of accurate prediction, whereas the second layer deployed a general stacking model. Sandwip, a southeasterly coastal zone in Bangladesh's Chittagong region, serves as the test site for weather parameters using daily data from 2007 to 2021 collected at the meteorological station. We conducted a comparative analysis of the proposed model and individual machine learning regressions as a potent tool to facilitate the enhancement of forecasting skills. Metrics such as coefficient of determination, mean absolute percentage error, mean squared error, and mean absolute error were used to assess the models. The result demonstrated that the proposed model demonstrated superior performance compared to other models in predicting each weather parameter. Precisely, the research obtained the most optimal R-squared values (0.945, 0.684, and 0.947) in predicting temperature, humidity, and sealevel pressure, respectively. A comprehensive analysis of extreme weather conditions was conducted based on forecasted weather variables, which is beneficial for the inhabitants of any coastal island in Bangladesh. [ABSTRACT FROM AUTHOR]

The observed cooling in the subpolar North Atlantic, known as the warming hole, is receiving much attention because of its relationship with the climate sensitivity in the Earth System Models (ESMs). However, the impact of its future projection on the global climate remains unclear due to large uncertainties. Here, we show that the future warming hole changes will affect the interhemispheric asymmetry of temperature and precipitation by modulating the Northern Hemisphere (NH) warming. Models with a weaker warming hole in the future project stronger NH warming by injecting more non‐radiative fluxes to the atmosphere. This leads to an asymmetric warming contrast between the two hemispheres, resulting in a meridional shift of the Inter‐Tropical Convergence Zone and more precipitation increases in the NH. Our study implies that the future warming hole controls the interhemispheric heat exchanges and associated changes in the global temperature and precipitation, suggesting that its improved simulation is essential. Plain Language Summary: The simulation of future warming hole intensity remains a major uncertainty in the Earth system models (ESMs) and its climatic impact is unclear. Here, using the ESMs, we show that future changes in the warming hole cause the interhemispheric asymmetry of temperature and precipitation. The warming of the warming hole injects non‐radiative fluxes into the atmosphere, amplifying more warming in the Northern Hemisphere than the Southern Hemisphere. Concurrently, this creates an energy imbalance between two hemispheres that leads to a northward shift of the Inter‐Tropical Convergence Zone, resulting in the interhemispheric asymmetry of precipitation. Key Points: Future warming hole changes in Coupled Model Intercomparison Phase 6 models affect the interhemispheric asymmetry of temperatureGreater warming in the warming hole increases the non‐radiative fluxes in the Northern Hemisphere, leading to an increase in the interhemispheric asymmetryThe warming hole affects future global precipitation by modulating the location of the ITCZ [ABSTRACT FROM AUTHOR]

Quantitative constraints on past mean ocean temperature (MOT) critically inform our historical understanding of Earth's energy balance. A recently developed MOT proxy based on paleoatmospheric Xe, Kr, and N2 ratios in ice core air bubbles is a promising tool rooted in the temperature dependences of gas solubilities. However, these inert gases are systematically undersaturated in the modern ocean interior, and it remains unclear how air‐sea disequilibrium may have changed in the past. Here, we carry out 30 tracer‐enabled model simulations under varying circulation, sea ice cover, and wind stress regimes to evaluate air‐sea disequilibrium in the Last Glacial Maximum (LGM) ocean. We find that undersaturation of all three gases was likely reduced, primarily due to strengthened high‐latitude winds, biasing reconstructed MOT by −0.38 ± 0.37°C (1σ). Accounting for air‐sea disequilibrium, paleoatmospheric inert gases indicate that LGM MOT was 2.27 ± 0.46°C (1σ) colder than the pre‐industrial era. Plain Language Summary: The ocean plays a central role in Earth's climate system as a major reservoir of heat. Understanding how ocean heat content (OHC) changed in the past is therefore key to unraveling the history of global climate. Xenon, krypton, and nitrogen trapped in ice core air bubbles offer a means of reconstructing past OHC, because changes in global ocean temperature affect the solubilities of these gases in seawater, leading to corresponding changes in their atmospheric abundances. For example, a colder ocean can hold more xenon, meaning less xenon resides in the atmosphere. However, these gases in the ocean today are slightly out of equilibrium with the atmosphere (i.e., they are undersaturated), and it remains unclear to what extent this disequilibrium could have changed in the past. We carried out global atmosphere‐ocean model simulations, finding that undersaturation was likely reduced in the Last Glacial Maximum (LGM), a colder era of global climate ∼20,000 years ago. Our analysis suggests that a small component of the additional xenon in the colder LGM ocean arose from this change in air‐sea disequilibrium. After accounting for this effect, ice core noble gas measurements suggest a slightly warmer LGM ocean than previously thought. Key Points: Global ocean air‐sea gas exchange simulations suggest reduced undersaturation of inert gases in the Last Glacial Maximum (LGM) oceanReduced LGM undersaturation indicates a small cold bias in mean ocean temperature (MOT) reconstruction from ice core noble gasesA revised estimate of MOT, accounting for air‐sea disequilibrium, is 2.27 ± 0.46°C colder than the pre‐industrial era [ABSTRACT FROM AUTHOR]

It is not clear how the Asian monsoon evolved after leaving the spatial range of the Intertropical Convergence Zone in the Late Eocene and before the modern‐like Asian monsoon formed at ∼26 Ma. In this study, the results of a well‐dated, robust, and continuous paleoenvironmental carbonate oxygen isotope record from the Tuotuohe section in the Tuotuohe Basin on the central–northern Tibetan Plateau indicate that the carbonate oxygen isotope showed positive bias at 30.5 Ma. Evidence concerning the temperature, precipitation, paleolatitude, paleoelevation, salt mines and global temperature changes at this time suggest that the positive oxygen isotope shift was mainly due to a combination of the intrusion of the Indian monsoon into the basin and increased evaporation, both of which were ultimately induced by the tectonic uplift of the Tuotuohe Basin before 30.5 Ma and the retreat of the Paratethys Sea after the Eocene. Key Points: Carbonate oxygen isotope in the Tuotuohe Basin has an evident positive shift at 30.5 MaThe Indian monsoon intruded into the Tuotuohe Basin at 30.5 MaThe intrusion of the Indian monsoon mainly induced by the tectonic uplifts of the Tuotuohe Basin before 30.5 Ma [ABSTRACT FROM AUTHOR]

As more countries make net zero greenhouse gas emissions pledges, it is crucial to understand the effects on global climate after achieving net zero emissions. The climate has been found to continue to evolve even after the abrupt cessation of CO2 emissions, with some models simulating a small warming and others simulating a small cooling. In this study, we analyze if the temperature and precipitation changes post abrupt cessation of CO2 emissions are significantly different compared to natural climate variations. We find that the temperature changes are outside of natural variability for most models, whilst the precipitation changes are mostly non‐significant. We also demonstrate that post‐net zero temperature changes have implications for the remaining carbon budget. The possibility of further global warming post‐net zero adds to the evidence supporting more rapid emissions reductions in the near‐term. Plain Language Summary: As more countries commit to achieving net‐zero greenhouse gas emissions, it is essential to understand the impact this will have on the global climate beyond this point. It has been found that even after CO2 emissions are abruptly halted, the climate continues to change, with various models predicting either a slight warming or cooling effect. In our study, we investigate whether the temperature and precipitation changes that occur after the sudden cessation of CO2 emissions are noteworthy when compared to natural climate variations. Our analysis reveals that the temperature changes, in the majority of models, surpass what can be attributed to natural variability. However, the precipitation changes are generally not significant. Additionally, we observe that the temperature changes post‐net zero have implications for the remaining carbon budget. Key Points: Global mean surface temperature changes after abrupt CO2 emissions cessation are significant compared to natural variability in most modelsGlobal mean precipitation changes after 50 yrs are only significant compared to natural variability in models that warmThe uncertain temperature changes post‐net zero have implications for the remaining carbon budget [ABSTRACT FROM AUTHOR]