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AimsWhile a centralized system for the care of patients with a sarcoma has been advocated for decades, regional variations in survival remain unclear. The aim of this study was to investigate regional variations in survival and the impact of national policies in patients with a soft-tissue sarcoma (STS) in the UK.MethodsThe study included 1,775 patients with a STS who were referred to a tertiary sarcoma centre. The geographical variations in survival were evaluated according to the periods before and after the issue of guidance by the National Institute for Health and Care Excellence (NICE) in 2006 and the relevant evolution of regional management.ResultsThere had been a significant difference in survival between patients referred from the North East, North West, East Midlands, West Midlands, South West, and Wales in the pre-NICE era (five-year disease-specific survival (DSS); South West, 74% vs North East, 47% (p = 0.045) or West Midlands, 54% (p = 0.049)), which was most evident for patients with a high-grade STS. However, this variation disappeared in the post-NICE era, in which the overall DSS for high-grade STS improved from 47% to 68% at five years (p < 0.001). Variation in the size of the tumour closely correlated with the variation in DSS, and the overall size of the tumour and incidence of metastasis at the time of diagnosis also decreased after the national policies were issued.ConclusionThe survival of patients with a STS improved and regional variation corrected after the introduction of national policies, as a result of a decreasing size of tumour and incidence of metastasis at the time of diagnosis, particularly in patients with a high-grade STS. This highlights the positive impact of national guidelines on regional variation in the presentation, management, and outcome in patients with a STS.Cite this article: Bone Joint J2021;103-B(9):1541–1549.

The land ice contribution to global mean sea level rise has not yet been predicted1using ice sheet and glacier models for the latest set of socio-economic scenarios, nor using coordinated exploration of uncertainties arising from the various computer models involved. Two recent international projects generated a large suite of projections using multiple models2–8, but primarily used previous-generation scenarios9and climate models10, and could not fully explore known uncertainties. Here we estimate probability distributions for these projections under the new scenarios11,12using statistical emulation of the ice sheet and glacier models. We find that limiting global warming to 1.5 degrees Celsius would halve the land ice contribution to twenty-first-century sea level rise, relative to current emissions pledges. The median decreases from 25 to 13 centimetres sea level equivalent (SLE) by 2100, with glaciers responsible for half the sea level contribution. The projected Antarctic contribution does not show a clear response to the emissions scenario, owing to uncertainties in the competing processes of increasing ice loss and snowfall accumulation in a warming climate. However, under risk-averse (pessimistic) assumptions, Antarctic ice loss could be five times higher, increasing the median land ice contribution to 42 centimetres SLE under current policies and pledges, with the 95th percentile projection exceeding half a metre even under 1.5 degrees Celsius warming. This would severely limit the possibility of mitigating future coastal flooding. Given this large range (between 13 centimetres SLE using the main projections under 1.5 degrees Celsius warming and 42 centimetres SLE using risk-averse projections under current pledges), adaptation planning for twenty-first-century sea level rise must account for a factor-of-three uncertainty in the land ice contribution until climate policies and the Antarctic response are further constrained.

AimsMalignancy and surgery are risk factors for venous thromboembolism (VTE). We undertook a systematic review of the literature concerning the prophylactic management of VTE in orthopaedic oncology patients.MethodsMEDLINE (PubMed), EMBASE (Ovid), Cochrane, and CINAHL databases were searched focusing on VTE, deep vein thrombosis (DVT), pulmonary embolism (PE), bleeding, or wound complication rates.ResultsIn all, 17 studies published from 1998 to 2018 met the inclusion criteria for the systematic review. The mean incidence of all VTE events in orthopaedic oncology patients was 10.7% (1.1% to 27.7%). The rate of PE was 2.4% (0.1% to 10.6%) while the rate of lethal PE was 0.6% (0.0% to 4.3%). The overall rate of DVT was 8.8% (1.1% to 22.3%) and the rate of symptomatic DVT was 2.9% (0.0% to 6.2%). From the studies that screened all patients prior to hospital discharge, the rate of asymptomatic DVT was 10.9% (2.0% to 20.2%). The most common risk factors identified for VTE were endoprosthetic replacements, hip and pelvic resections, presence of metastases, surgical procedures taking longer than three hours, and patients having chemotherapy. Mean incidence of VTE with and without chemical prophylaxis was 7.9% (1.1% to 21.8%) and 8.7% (2.0% to 23.4%; p = 0.11), respectively. No difference in the incidence of bleeding or wound complications between prophylaxis groups was reported.ConclusionCurrent evidence is limited to guide clinicians. It is our consensus opinion, based upon logic and deduction, that all patients be considered for both mechanical and chemical VTE prophylaxis, particularly in high-risk patients (pelvic or hip resections, prosthetic reconstruction, malignant diagnosis, presence of metastases, or surgical procedures longer than three hours). Additionally, the surgeon must determine, in each patient, if the risk of haemorrhage outweighs the risk of VTE. No individual pharmacological agent has been identified as being superior in the prevention of VTE events.Cite this article: Bone Joint J2020;102-B(12)1743:–1751.

AbstractGiven graphs Gand Hand a positive integer k, the Gallai-Ramsey number is the minimum integer Nsuch that for any integer every k-edge-coloring of Kncontains either a rainbow copy of Gor a monochromatic copy of H. These numbers have recently been studied for the case when where still only a few precise numbers are known for all k. In this paper, we extend the known precise Gallai-Ramsey numbers to include for all k.

AimsThe existing clinical guidelines do not describe a clear indication for adjuvant radiotherapy (RT) in the treatment of superficial soft tissue sarcomas (STSs). We aimed to determine the efficacy of adjuvant RT for superficial STSs.MethodsWe retrospectively studied 304 patients with superficial STS of the limbs and trunk who underwent surgical resection at a tertiary sarcoma centre. The efficacy of RT was investigated according to the tumour size and grade: group 1, ≤ 5 cm, low grade; group 2, ≤ 5cm, high grade; group 3, > 5 cm, low grade; group 4, > 5 cm, high grade.ResultsThe five- and ten-year local recurrence-free survival (LRFS) for all patients was 88% and 81%, respectively. While the efficacy of adjuvant RT was not proven in local control of all patients (five-year LRFS; RT+, 90% versus RT-, 83%; p = 0.074), the LRFS was significantly improved by adjuvant RT in group 2 (five-year LRFS; RT+, 96% versus RT-, 82%; p = 0.019), and group 4 (five-year LRFS; RT+, 87% versus RT-, 73%; p = 0.027). In groups 2 and 4, adjuvant RT significantly reduced the LR risk if the resection margin was clear but less than 5 mm; the LR rate was 7% with adjuvant RT compared with 26% with surgery alone (p = 0.003). There was no statistical relationship with the use of adjuvant RT and survival in every group.ConclusionAdjuvant RT reduces the risk of local recurrence in patients with superficial high-grade STS regardless of tumour size, especially when resection margin is less than 5 mm.Cite this article: Bone Joint J2020;102-B(8):1088–1094.

Greenhouse gases and aerosols play a major role in controlling global climate change. Greenhouse gases drive a radiative imbalance which warms the ocean, while aerosols cool the ocean. Since 1980, the effective radiation felt by the planet due to anthropogenic aerosols has leveled off, global ocean cooling due to aerosols has decelerated, and greenhouse gas‐driven ocean warming has accelerated. We explore the deceleration of aerosol‐driven ocean cooling by quantifying a time‐ and spatially varying ocean heat uptake efficiency, defined as the change in the rate of global ocean heat storage per degree of cooling surface temperature. In aerosol‐only simulations, ocean heat uptake efficiency has decreased by 43 ± 14% since 1980. The tropics and sub‐tropics have driven this decrease, while the coldest fraction of the ocean continues to sustain cooling and high ocean heat uptake efficiency. Our results identify a growing trend toward less efficient ocean cooling due to aerosols. The composition of the atmosphere has a major impact on our climate. Greenhouse gases warm the planet, while aerosols (i.e., suspensions of particles in the atmosphere) cool the planet, and most of this change is absorbed by the oceans. Since 1980, the rate of cooling of the planet due to aerosols has plateaued. In the past few decades, the ocean has begun to equilibrate to this change, and this work explores where and when this equilibration has occurred in the ocean based on global climate models. To understand this change, we use an “ocean heat uptake efficiency” metric which describes how much additional heat builds up in the ocean for a given degree of surface temperature gain (or loss). We find that the ocean is cooling more slowly given a degree of surface cooling due to aerosols compared to the pre‐1980s. This change is largely driven by the tropics and sub‐tropics, where the ocean has stopped cooling in response to aerosol‐driven negative surface temperatures. Polar and sub‐polar regions, however, continue to cool due to aerosols. These changes are occurring alongside accelerating greenhouse gas‐driven warming, suggesting that the relative role of aerosols in cooling our climate is weakening. Since 1980, aerosol‐driven ocean cooling has decelerated substantially, alongside a drop in ocean heat uptake efficiencyThe drop in ocean heat uptake efficiency is limited to the tropics, which may have equilibrated to ongoing aerosol‐driven radiative forcingAir‐sea fluxes into the coldest fraction of the ocean continue to offset greenhouse gas‐driven ocean warming Since 1980, aerosol‐driven ocean cooling has decelerated substantially, alongside a drop in ocean heat uptake efficiency The drop in ocean heat uptake efficiency is limited to the tropics, which may have equilibrated to ongoing aerosol‐driven radiative forcing Air‐sea fluxes into the coldest fraction of the ocean continue to offset greenhouse gas‐driven ocean warming

In most coupled climate models, effective climate sensitivity increases for a few decades following an abrupt CO2increase. The change in the climate feedback parameter between the first 20 years and the subsequent 130 years is highly model dependent. In this study, we suggest that the intermodel spread of changes in climate feedback can be partially traced to the evolution of the Atlantic Meridional Overturning Circulation. Models with stronger Atlantic Meridional Overturning Circulation recovery tend to project more amplified warming in the Northern Hemisphere a few decades after a quadrupling of CO2. Tropospheric stability then decreases as the Northern Hemisphere gets warmer, which leads to an increase in both the lapse‐rate and shortwave cloud feedbacks. Our results suggest that constraining future ocean circulation changes will be necessary for accurate climate sensitivity projections. How much the Earth's climate will warm in response to increasing carbon dioxide concentration, a number known as climate sensitivity, is an essential metric of the impacts of anthropogenic climate change. Most current global climate models agree that the climate will become more sensitive as time passes, indicating an underestimation of future warming inferred from historical records. In this study, we report that the slow response of oceanic circulation has an influence on this time evolution of climate sensitivity. In the 15 state‐of‐the‐art global climate models we investigate, the models projecting restrengthening of Atlantic Meridional Overturning Circulation after a few decades of weakening tend to simulate a more significant increase in climate sensitivity. We propose a mechanism as follows: Atlantic Meridional Overturning Circulation strengthening causes more enhanced surface warming in the Northern Hemisphere, altering the vertical stability of the global atmosphere. The changes in atmospheric vertical stability then strengthen the radiative feedbacks that amplify greenhouse gas forcing, accounting for the larger increase in climate sensitivity in these models. Our findings emphasize the important contribution of ocean circulation to the intermodel spread in climate change projections. Uncertainty in the Atlantic Meridional Overturning Circulation is the main cause of the model spread in evolution of the warming patternWarming in Northern Hemisphere extratropics tends to be surface trapped, leading to more positive lapse‐rate and cloud feedbacksModels with stronger recovery in Atlantic Meridional Overturning Circulation tend to project a larger increase in net climate feedback

AimsThe aim of this study was to report the outcomes of patients who underwent definitive surgery for secondary chondrosarcomas arising from osteochondromas.Patients and MethodsA total of 51 patients with secondary chondrosarcomas occurring from osteochondromas were reviewed. Median age was 36 years (interquartile range (IQR) 15 to 82). Median follow-up was 6.9 years (IQR 2.8 to 10.6). The pelvis was the most commonly affected site (59%). Histological grades were grade I in 35 (69%), grade II in 13 (25%), and grade III in three patients (6%).ResultsPreoperative biopsy histology correctly predicted the final histological grade in 27% of patients. The ten-year disease-specific survival (DSS) for all patients was 89.4%. Local recurrence occurred in 15 patients (29%), more commonly in pelvic tumours (37%) compared with limb tumours (19%). Four patients with pelvic tumours died from progression of local recurrence. No patient with limb tumours died of disease. Wide/radical margin was associated with improved local recurrence-free survival (p = 0.032) and local recurrence was associated with worse DSS (p = 0.005).ConclusionWe recommend that a secondary chondrosarcoma arising from osteochondroma of the pelvis is resected with wide/radical resection margins. The balance between the morbidity of surgery and risk of local recurrence needs to be considered in patients with limb secondary chondrosarcomas.Cite this article: Bone Joint J2019;101-B:1313–1320

The Ocean Heat Uptake Efficiency (OHUE) quantifies the ocean's ability to mitigate surface warming through deep heat sequestration. Despite its importance, the main controls on OHUE, and on its two‐fold spread across contemporary climate models, remain unclear. We argue that OHUE is primarily controlled by mid‐latitude ventilation strength in the background climate, itself related to pycnocline depth and stratification. This hypothesis is supported by a strong correlation between mid‐latitude (30–60°) OHUE and the near‐global average (60°S–60°N) pycnocline depth in CMIP5 and CMIP6 AOGCMs under RCP85/SSP585, and in a parameter perturbation ensemble of ocean GCM (MITgcm) experiments. This correlation explains about 70% of the CMIP5‐6 spread in global OHUE. The relationship provides a pathway toward observationally constraining OHUE, and thus reducing uncertainty in projections of future global climate change and sea level rise. The ocean absorbs most of the excess heat in the climate system. How effectively this process reduces surface warming depends on how deeply this heat is stored in the ocean, which varies widely across contemporary climate models. Our study shows that around 70% of the variation in deep heat storage across models is explained by differences is how water from the mid‐latitude surface ocean is transported to deeper ocean layers by ocean currents. This difference can be measured by the stratification of seawater density in the base‐state climate, a feature that can be observed in the modern ocean. We show this relationship using a new regional decomposition method. The results of this study can be leveraged with ocean observations to reduce uncertainty in future climate and sea level rise projections. Pycnocline depth correlates strongly with Ocean Heat Uptake Efficiency (OHUE) in CMIP5/CMIP6 and MITgcmA regional OHUE decomposition shows that mid‐latitude heat uptake and sequestration drives the correlation between OHUE of pycnocline depthInter‐model differences in pycnocline depth explain around 70% of the spread in OHUE across CMIP5 and CMIP6 Pycnocline depth correlates strongly with Ocean Heat Uptake Efficiency (OHUE) in CMIP5/CMIP6 and MITgcm A regional OHUE decomposition shows that mid‐latitude heat uptake and sequestration drives the correlation between OHUE of pycnocline depth Inter‐model differences in pycnocline depth explain around 70% of the spread in OHUE across CMIP5 and CMIP6

We investigate the time‐dependence of radiative feedback in the historical period (since the late 19th century), by analyzing experiments using coupled atmosphere–ocean climate models with historical greenhouse gas, anthropogenic aerosol, and natural forcings, each separately. We find that radiative feedback depends on forcing agent, primarily through the effect of cloud on shortwave radiation, because the various forcings cause different changes in global‐mean tropospheric stability per degree of global‐mean temperature change. The large time‐variation of historical feedback driven by observed sea surface temperature change alone, with no forcing agents, is also consistent with tropospheric stability change, and differs from the similarly large and significant historical time‐variation of feedback that is simulated in response to all forcing agents together. We show that the latter results from the varying relative sizes of individual forcings. We highlight that volcanic forcing is especially important for understanding the time‐variation, because it stimulates particularly strong feedbacks that tend to reduce effective climate sensitivity. We relate this to stability changes due to enhanced surface temperature response in the Indo‐Pacific warm pool. Historical climate change, driven by energy flow into the Earth system, is due to a variety of different influences, called “forcing agents.” The main ones are greenhouse gases and small particles in the atmosphere (called “aerosols”) emitted by human activities, as well as aerosols that are produced in the upper atmosphere by explosive volcanic eruptions. Each of these historical forcing agents varies significantly over the historical period. By studying them separately, we explain how they together explain the evolution of global temperature since the mid‐19th century. Differences among the change in global temperature produced by the various forcing agents are explained by their different effects on the vertical contrast of temperature change within the lower atmosphere, because this in turn affects the amount of low cloud, which reflects sunlight and tends to cool the planet. Of all the forcing agents, volcanic aerosols produce the least global temperature change per unit of forcing. This might be because the volcanic aerosol is present for only a few years at a time in the atmosphere, following each eruption. The time‐evolution of simulated historical radiative feedback is explained by the variation in the relative sizes of different forcingsThis is because forcings differ in the change they cause to global‐mean tropospheric stability per degree of global‐mean temperature changeEffective climate sensitivity is markedly lower to volcanic than greenhouse‐gas forcing due to efficient cooling of the Pacific warm pool The time‐evolution of simulated historical radiative feedback is explained by the variation in the relative sizes of different forcings This is because forcings differ in the change they cause to global‐mean tropospheric stability per degree of global‐mean temperature change Effective climate sensitivity is markedly lower to volcanic than greenhouse‐gas forcing due to efficient cooling of the Pacific warm pool

Eight atmospheric general circulation models (AGCMs) are forced with observed historical (1871–2010) monthly sea surface temperature and sea ice variations using the Atmospheric Model Intercomparison Project II data set. The AGCMs therefore have a similar temperature pattern and trend to that of observed historical climate change. The AGCMs simulate a spread in climate feedback similar to that seen in coupled simulations of the response to CO2quadrupling. However, the feedbacks are robustly more stabilizing and the effective climate sensitivity (EffCS) smaller. This is due to a pattern effect, whereby the pattern of observed historical sea surface temperature change gives rise to more negative cloud and longwave clear‐sky feedbacks. Assuming the patterns of long‐term temperature change simulated by models, and the radiative response to them, are credible; this implies that existing constraints on EffCS from historical energy budget variations give values that are too low and overly constrained, particularly at the upper end. For example, the pattern effect increases the long‐term Otto et al. (2013, https://doi.org/10.1038/ngeo1836) EffCS median and 5–95% confidence interval from 1.9 K (0.9–5.0 K) to 3.2 K (1.5–8.1 K). Recent decades have seen cooling over the eastern tropical Pacific and Southern Oceans while temperatures rise globally. Climate models indicate that these regional features, and others, are not expected to continue into the future under sustained forcing from atmospheric carbon dioxide increases. This matters because climate sensitivity depends on the pattern of warming, so if the past has warmed differently from what we expect in the future, then climate sensitivity estimated from the historical record may not apply to the future. We investigate this with a suite of climate models and show that climate sensitivity simulated for observed historical climate change is smaller than for long‐term carbon dioxide increases. The results imply that historical energy budget changes only weakly constrain climate sensitivity. Climate sensitivity simulated for observed surface temperature change is smaller than for long‐term carbon dioxide increasesObserved historical energy budget constraints give climate sensitivity values that are too low and overly constrained, particularly at the upper endHistorical energy budget changes only weakly constrain climate sensitivity

Transient climate response (TCR), transient response at 140 years (T140), and equilibrium climate sensitivity (ECS) indices are intended as benchmarks for comparing the magnitude of climate response projected by climate models. It is generally assumed that TCR or T140 would explain more variability between models than ECS for temperature change over the 21st century, since this timescale is the realm of transient climate change. Here we find that TCR explains more variability across Coupled Model Intercomparison Project phase 5 than ECS for global temperature change since preindustrial, for 50 or 100 year global trends up to the present, and for projected change under representative concentration pathways in regions of delayed warming such as the Southern Ocean. However, unexpectedly, we find that ECS correlates higher than TCR for projected change from the present in the global mean and in most regions. This higher correlation does not relate to aerosol forcing, and the physical cause requires further investigation. We compare transient climate response (TCR), 140 year TCR (T140), and equilibrium climate sensitivity (ECS) as measures of projected warmingT140 provides the highest R2with the warming relative to preindustrial, but R2is higher with ECS in 100 year trends from circa 1960 onwardThere are large spatial differences in the fit of temperature projections to sensitivity, with lower values in regions of delayed warming

The use of silver in the treatment and prevention of infection is widespread in the medical community today. Advances in technology have enabled its use to be incorporated into orthopaedic practice with increasing success. This review aims to examine the different types of silver use in orthopaedics along with a review of the literature to assess the clinical efficacy of this emerging treatment.

We investigate the dependence of radiative feedback on the pattern of sea‐surface temperature (SST) change in 14 Atmospheric General Circulation Models (AGCMs) forced with observed variations in SST and sea‐ice over the historical record from 1871 to near‐present. We find that over 1871–1980, the Earth warmed with feedbacks largely consistent and strongly correlated with long‐term climate sensitivity feedbacks (diagnosed from corresponding atmosphere‐ocean GCM abrupt‐4xCO2simulations). Post 1980, however, the Earth warmed with unusual trends in tropical Pacific SSTs (enhanced warming in the west, cooling in the east) and cooling in the Southern Ocean that drove climate feedback to be uncorrelated with—and indicating much lower climate sensitivity than—that expected for long‐term CO2increase. We show that these conclusions are not strongly dependent on the Atmospheric Model Intercomparison Project (AMIP) II SST data set used to force the AGCMs, though the magnitude of feedback post 1980 is generally smaller in nine AGCMs forced with alternative HadISST1 SST boundary conditions. We quantify a “pattern effect” (defined as the difference between historical and long‐term CO2feedback) equal to 0.48 ± 0.47 [5%–95%] W m−2K−1for the time‐period 1871–2010 when the AGCMs are forced with HadISST1 SSTs, or 0.70 ± 0.47 [5%–95%] W m−2K−1when forced with AMIP II SSTs. Assessed changes in the Earth's historical energy budget agree with the AGCM feedback estimates. Furthermore satellite observations of changes in top‐of‐atmosphere radiative fluxes since 1985 suggest that the pattern effect was particularly strong over recent decades but may be waning post 2014. Post 1980 the Earth warmed with feedbacks uncorrelated with—and indicating much lower equilibrium climate sensitivity than—that expected for long‐term CO2increaseSatellite observations of changes in top‐of‐atmosphere radiative fluxes since 1985 are in agreement with the modelsThe pattern effect may be waning post 2014 Post 1980 the Earth warmed with feedbacks uncorrelated with—and indicating much lower equilibrium climate sensitivity than—that expected for long‐term CO2increase Satellite observations of changes in top‐of‐atmosphere radiative fluxes since 1985 are in agreement with the models The pattern effect may be waning post 2014

The classic vertical advection‐diffusion (VAD) balance is a central concept in studying the ocean heat budget, in particular in simple climate models (SCMs). Here we present a new framework to calibrate the parameters of the VAD equation to the vertical ocean heat balance of two fully‐coupled climate models that is traceable to the models' circulation as well as to vertical mixing and diffusion processes. Based on temperature diagnostics, we derive an effective vertical velocity w∗and turbulent diffusivity kν∗for each individual physical process. In steady state, we find that the residual vertical velocity and diffusivity change sign in middepth, highlighting the different regional contributions of isopycnal and diapycnal diffusion in balancing the models' residual advection and vertical mixing. We quantify the impacts of the time evolution of the effective quantities under a transient 1% CO2simulation and make the link to the parameters of currently employed SCMs. The advection‐diffusion equation is calibrated to the heat balance of two AOGCMsThe process‐based parameters wand kνchange sign in middepth oceanThe time evolution of the effective quantities is key in transient ocean uptake

State-of-the-art climate models now include more climate processes simulated at higher spatial resolution than ever. Nevertheless, some processes, such as atmospheric chemical feedbacks, are still computationally expensive and are often ignored in climate simulations. Here we present evidence that the representation of stratospheric ozone in climate models can have a first-order impact on estimates of effective climate sensitivity. Using a comprehensive atmosphere–ocean chemistry–climate model, we find an increase in global mean surface warming of around 1 °C (20%) after 75 years when ozone is prescribed at pre-industrial levels compared with when it is allowed to evolve self-consistently in response to an abrupt 4×CO2forcing. The difference is primarily attributed to changes in long-wave radiative feedbacks associated with circulation-driven decreases in tropical lower stratospheric ozone and related stratospheric water vapour and cirrus cloud changes. This has important implications for global model intercomparison studies in which participating models often use simplified treatments of atmospheric composition changes that are consistent with neither the specified greenhouse gas forcing scenario nor the associated atmospheric circulation feedbacks.

Anthropogenic ocean heat uptake is a key factor in determining climate change and sea level rise. There is considerable uncertainty in projections of freshwater forcing of the ocean, with the potential to influence ocean heat uptake. We investigate this by adding either −0.1 Sv (sverdrup (106m3/s)) or +0.1 Sv freshwater to the Atlantic in global climate model simulations, simultaneously imposing an atmospheric CO2increase. The resulting changes in the Atlantic meridional overturning circulation are roughly equal and opposite (±2 Sv). The impact of the perturbation on ocean heat content is more complex, although it is relatively small (∼5%) compared to the total anthropogenic heat uptake. Several competing processes either accelerate or retard warming at different depths. While positive freshwater perturbations cause an overall heating of the Atlantic, negative perturbations produce insignificant net changes in heat content. The processes active in our model appear robust, although their net result is likely model dependent and experiment dependent. Ocean freshwater forcing produces complex changes in anthropogenic heat uptakeIn our model, freshwater anomalies of both signs give a net increase in heatingThe simulated differences are small compared to total anthropogenic heat uptake

Letter to the Editor

Experiments with seven Coupled Model Intercomparison Project phase 6 models were used to assess the climate feedback parameter for net historical, historical greenhouse gas (GHG) and anthropogenic aerosol forcings. The net radiative feedback is found to be more amplifying (higher effective climate sensitivity) for aerosol than GHG forcing, and hence also less amplifying for net historical (GHG + aerosol) than GHG only. We demonstrate that this difference is consistent with their different latitudinal distributions. Historical aerosol forcing is most pronounced in northern extratropics, where the boundary layer is decoupled from the free troposphere, so the consequent temperature change is confined to low altitude and causes low‐level cloud changes. This is caused by change in stability, which also affects upper‐tropospheric clear‐sky emission, affecting both shortwave and longwave radiative feedbacks. This response is a feature of extratropical forcing generally, regardless of its sign or hemisphere. Understanding how the Earth's surface temperatures change in accordance with the anomalous energy flow into the system due to changes in greenhouse gases (GHGs) or anthropogenic aerosols is vital for predicting future temperature change. New data have made it possible to better calculate how efficiently the planet responds to temperature change (so as to return to energy equilibrium) for historical aerosols and GHGs. We find that the Earth requires greater surface temperature changes under aerosol climate forcing than it does for GHGs in order to balance out incoming and outgoing energy into the Earth system. By comparing with experiments that prescribe energy changes only outside the tropics, we find that the lower efficiency of aerosols in damping the radiative imbalance is related to their being mainly located away from the equator, unlike GHGs which are generally well mixed throughout the globe. This forcing away from the equator is tied to the vertical distribution of temperature changes. This distribution affects how efficiently surface temperature change leads to balancing the incoming and outgoing energy into the Earth system. Surface temperature can thus change differently for the same global average forcings. Effective climate sensitivity is larger (feedback more amplifying) for historical anthropogenic aerosol than greenhouse‐gas (GHG) forcing in Coupled Model Intercomparison Project phase 6The key difference is that GHG forcing is global and aerosols are mainly extratropical (and aerosol hemispheric contrast unimportant)Extratropical forcing causes a shallower temperature response than tropical forcing, hence more amplifying cloud and lapse‐rate feedbacks Effective climate sensitivity is larger (feedback more amplifying) for historical anthropogenic aerosol than greenhouse‐gas (GHG) forcing in Coupled Model Intercomparison Project phase 6 The key difference is that GHG forcing is global and aerosols are mainly extratropical (and aerosol hemispheric contrast unimportant) Extratropical forcing causes a shallower temperature response than tropical forcing, hence more amplifying cloud and lapse‐rate feedbacks

Although global mean sea‐level rise since 1900 and regional mean sea‐level change since the 1960s have been accounted for in terms of the sum of contributions, the same budget closure has not been achieved for local relative sea‐level change from a global network of tide gauges. To address this, we combine new estimates of sterodynamic sea‐level change (SDSL; including ocean dynamics), glacial isostatic adjustment (GIA), change in land ice mass and terrestrial water storage, and other local vertical land motion. We find that the observed trends over 1958–2015 at all 272 tide gauges distributed worldwide agree with the sum of contributions (within 90% confidence estimates), with similar mean trend (1.1 mm yr−1) and comparable spatial variability (standard deviation of 2.0 and 1.9 mm yr−1respectively). SDSL is the dominant contribution to both local observed mean trend and spatial variability, except at locations close to former ice‐sheets, where GIA dominates. Understanding the sea‐level budget, which has not previously been closed at local scales from a global network of tide gauges, is important because the densely populated coastal community is vulnerable to coastal sea‐level changes. The main contributions to global sea‐level change are thermal expansion, ocean mass increase from the loss of mass from ice sheets, glaciers, and water mass redistribution between the land and oceans. To evaluate the local sea‐level budget closure (whether the sum of these contributions equals local sea‐level observations), we compare the linear trend of the sum of contributions with the sea‐level observations measured by the tide gauge stations and find that the sea‐level budget at all 272 tide gauge stations distributed globally are closed within the 90% confidence levels. Local sea‐level trends are dominated by the changes in ocean density and circulation in response to atmospheric forcing, and at stations close to regions of past land ice mass loss during the last deglaciation, the contribution from glacial isostatic adjustment due to ongoing solid Earth deformation is also important. At 272 tide gauges distributed globally, sea‐level trends over 1958–2015 agree with the sum of contributions within 90% confidence levelThe tide‐gauge mean trend agrees with the sum of contributions (1.1 mm yr−1) and their standard deviations are comparable too (∼2.0 mm yr−1)Inclusion of the local effect of ocean dynamics is the main reason for the improved local budget closure At 272 tide gauges distributed globally, sea‐level trends over 1958–2015 agree with the sum of contributions within 90% confidence level The tide‐gauge mean trend agrees with the sum of contributions (1.1 mm yr−1) and their standard deviations are comparable too (∼2.0 mm yr−1) Inclusion of the local effect of ocean dynamics is the main reason for the improved local budget closure

Effective radiative forcing includes a contribution by rapid adjustments, that is, changes in temperature, water vapor, and clouds that modify the energy budget. Cloud adjustments in particular have been shown to depend strongly on forcing agent. We perform idealized atmospheric heating experiments to demonstrate a relationship between cloud adjustment and the vertical profile of imposed radiative heating: boundary‐layer heating causes a positive cloud adjustment (a net downward radiative anomaly), while free‐tropospheric heating yields a negative adjustment. This dependence is dominated by the shortwave effect of changes in low clouds. Much of the variation in cloud adjustment among common forcing agents such as CO2, CH4, solar forcing, and black carbon is explained by the “characteristic altitude” (i.e., the vertical center‐of‐mass) of their heating profiles, through its effect on tropospheric stability. Changes in factors such as greenhouse gas concentrations or solar irradiance affect the balance of energy coming into versus leaving the earth's atmosphere, a phenomenon known as radiative forcing. This forcing can be modified by rapid atmospheric “adjustments” that occur in temperature, humidity, and cloud cover. The cloud component in particular of these rapid adjustments strongly depends on the forcing agent, for reasons that have been unclear. We find that the vertical structure of atmospheric heating explains much of the forcing agent dependence of the cloud adjustments: bottom‐heavier heating causes a more positive cloud adjustment. By understanding what happens when only a small portion of the atmosphere is heated, we show that it is possible to explain cloud adjustments to more complex forcings. We anticipate that our results will provide a physical basis to understand the causes of model‐to‐model differences in cloud adjustments. Cloud adjustment depends on the “characteristic altitude” of the atmospheric heating profileBoundary‐layer (free‐tropospheric) heating causes positive (negative) cloud adjustmentLow clouds dominate the cloud adjustment dependence on forcing altitude Cloud adjustment depends on the “characteristic altitude” of the atmospheric heating profile Boundary‐layer (free‐tropospheric) heating causes positive (negative) cloud adjustment Low clouds dominate the cloud adjustment dependence on forcing altitude

Projections of the sea level contribution from the Greenland and Antarctic ice sheets (GrIS and AIS) rely on atmospheric and oceanic drivers obtained from climate models. The Earth System Models participating in the Coupled Model Intercomparison Project phase 6 (CMIP6) generally project greater future warming compared with the previous Coupled Model Intercomparison Project phase 5 (CMIP5) effort. Here we use four CMIP6 models and a selection of CMIP5 models to force multiple ice sheet models as part of the Ice Sheet Model Intercomparison Project for CMIP6 (ISMIP6). We find that the projected sea level contribution at 2100 from the ice sheet model ensemble under the CMIP6 scenarios falls within the CMIP5 range for the Antarctic ice sheet but is significantly increased for Greenland. Warmer atmosphere in CMIP6 models results in higher Greenland mass loss due to surface melt. For Antarctica, CMIP6 forcing is similar to CMIP5 and mass gain from increased snowfall counteracts increased loss due to ocean warming. The melting of the Greenland and Antarctic ice sheets (GrIS and AIS) will result in higher sea level in the future. How sea level will change depends in part on how the atmosphere and ocean warm and how this affects the ice sheets. We use multiple ice sheet models to estimate possible future sea levels under climate scenarios from the models participating in the new Coupled Model Intercomparison Project phase 6 (CMIP6), which generally indicate a warmer world that the previous effort (CMIP5). Our results show that the possible future sea level change due Antarctica is similar for CMIP5 and CMIP6, but the warmer atmosphere in CMIP6 models leads to higher sea‐level contributions from Greenland by the end of the century. We compare results from an ice sheet model inter‐comparison forced using Coupled Model Intercomparison Project phase 6 and phase 5 climate projectionsProjected sea level at 2100 is higher for Greenland under CMIP6 scenarios than CMIP5, but similar for Antarctica under both scenariosCMIP6 warmer climate results in increased Greenland surface melt while increased snowfall mitigates loss from ocean warming for Antarctica We compare results from an ice sheet model inter‐comparison forced using Coupled Model Intercomparison Project phase 6 and phase 5 climate projections Projected sea level at 2100 is higher for Greenland under CMIP6 scenarios than CMIP5, but similar for Antarctica under both scenarios CMIP6 warmer climate results in increased Greenland surface melt while increased snowfall mitigates loss from ocean warming for Antarctica

Lists the largest publicly owned companies in St. Louis, Missouri ranked by 1998 revenue. Includes Emerson Electric Co.; May Department Stores Co.; Anheuser-Busch Cos. Inc.

The effective climate sensitivity (EffCS) of models in the Coupled Model Intercomparison Project 6 (CMIP6) has increased relative to CMIP5. We explore the implications of this for global mean sea‐level (GMSL) change projections in 2100 for three emissions scenarios. CMIP6 projections of global surface air temperature are substantially higher than in CMIP5, but projections of global mean thermal expansion are not. Using these projections as input to construct projections of GMSL change with IPCC AR5 methods, the 95th percentile of GMSL change at 2100 only increases by 3–7 cm. Projected rates of GMSL rise around 2100 increase more strongly, though, implying more pronounced differences beyond 2100 and greater committed sea‐level rise. Intermodel differences in GMSL projections indicate that EffCS‐based model selection may substantially alter the ensemble projections. GMSL change in 2100 is accurately predicted by time‐integrated temperature change, and thus requires reducing emissions early to be mitigated. Climate sensitivity measures how much the Earth's surface warms for a given increase in greenhouse gas concentration. In the new generation of global climate models, climate sensitivity has increased. We explore how the simulations of these models affect global mean sea‐level (GMSL) rise projections in 2100 for three different emissions scenarios. We compute GMSL projections based on simulated global surface warming (which affects land‐ice melt) and thermal expansion of the ocean, using the methods of the fifth Assessment Report of the Intergovernmental Panel on Climate Change. The latest projections of global surface warming are substantially higher than the previous projections, whereas the projections of global thermal expansion are not. Consequently, the upper limits of our GMSL projections increase by 3–7 cm depending on the emissions scenario. This difference will likely become more pronounced beyond 2100. Depending on climate sensitivity, GMSL projections for individual models can differ substantially, implying that using only a subset of models selected based on their climate sensitivity may substantially alter GMSL projections. Since GMSL in 2100 can be predicted well by the cumulative sum of surface warming up to 2100, it is important to reduce the emission of greenhouse gases early to mitigate GMSL rise. The 95th percentile of total sea‐level change projections in 2100 is up to 7 cm higher for the Coupled Model Intercomparison Project 6 (CMIP6) ensemble than for the CMIP5 ensembleThe 95th percentile of projected sea‐level rise rates near 2100 is up to 21% larger, implying more pronounced differences beyond 2100Depending on climate sensitivity, individual models can project global mean sea‐level rise substantially outside the ensemble 5%–95% range The 95th percentile of total sea‐level change projections in 2100 is up to 7 cm higher for the Coupled Model Intercomparison Project 6 (CMIP6) ensemble than for the CMIP5 ensemble The 95th percentile of projected sea‐level rise rates near 2100 is up to 21% larger, implying more pronounced differences beyond 2100 Depending on climate sensitivity, individual models can project global mean sea‐level rise substantially outside the ensemble 5%–95% range

Equilibrium climate sensitivity‐the equilibrium warming per CO2doubling‐increases with CO2concentration for 13 of 14 coupled general circulation models for 0.5–8 times the preindustrial concentration. In particular, the abrupt 4× CO2equilibrium warming is more than twice the 2× CO2warming. We identify three potential causes: nonlogarithmic forcing, feedback CO2dependence, and feedback temperature dependence. Feedback temperature dependence explains at least half of the sensitivity increase, while feedback CO2dependence explains a smaller share, and nonlogarithmic forcing decreases sensitivity in as many models as it increases it. Feedback temperature dependence is positive for 10 out of 14 models, primarily due to the longwave clear‐sky feedback, while cloud feedbacks drive particularly large sensitivity increases. Feedback temperature dependence increases the risk of extreme or runaway warming, and is estimated to cause six models to warm at least an additional 3K under 8× CO2. Increasing CO2reduces the rate at which energy leaves Earth, causing a net energy gain at its surface. The resulting warming increases the rate that energy leaves the planet. The planet stops warming once it regains balance. Studies usually assume that doubling atmospheric CO2always produces the same eventual global temperature rise (called the “equilibrium climate sensitivity”), whatever the starting CO2level. We show, on the contrary, that in nearly all the computer climate models we have examined, the extra warming for each doubling goes up as the CO2level increases. In most models, the warmer the climate becomes, the more it has to warm in order to balance a further CO2doubling because warming becomes less effective at rebalancing the flow of energy. This effect increases projections of warming, especially for scenarios of greatest CO2increase. Equilibrium warming per CO2doubling increases with CO2level for 13 of 14 climate modelsPositive feedback temperature dependence explains most of the sensitivity increaseNonlinear feedbacks increase the long‐term risk of extreme warming under high CO2emissions Equilibrium warming per CO2doubling increases with CO2level for 13 of 14 climate models Positive feedback temperature dependence explains most of the sensitivity increase Nonlinear feedbacks increase the long‐term risk of extreme warming under high CO2emissions

The article focuses on the findings of an investigation in which a percussion groove characteristic of Brazilian music was recorded and subsequently analyzed using research-grade acoustic analysis software. A 6-inch Brazilian framedrum called tamborim was used in the investigation. An acoustic analysis software package was used to analyze the time series. It concludes that swing is a rhythmic interpretation or distortion of what is actually written.

The climate's response to forcing depends on how efficiently heat is absorbed by the ocean. Much, if not most, of this ocean heat uptake results from the passive transport of warm surface waters into the ocean's interior. Here we examine how geographic patterns of surface warming influence the efficiency of this passive heat uptake process. We show that the average pattern of surface warming in CMIP5 damps passive ocean heat uptake efficiency by nearly 25%, as compared to homogeneous surface warming. This “pattern effect” occurs because strong ventilation and weak surface warming are robustly colocated, particularly in the Southern Ocean. However, variations in warming patterns across CMIP5 do not drive significant ensemble spread in passive ocean heat uptake efficiency. This spread is likely linked to intermodel differences in ocean circulation, which our idealized results suggest may be dominated by differences in Southern Ocean and subtropical ventilation processes. CMIP5‐average sea surface temperature patterns damp passive ocean heat uptake efficiency by 24%Variations in surface warming patterns between models do not explain the spread in ocean heat uptake efficiencyThe spread in ocean heat uptake efficiency likely stems from differences in ocean circulation across CMIP5

The Atlantic Meridional Overturning Circulation (AMOC) has been, and will continue to be, a key factor in the modulation of climate change both locally and globally. However, there remains considerable uncertainty in recent AMOC evolution. Here, we show that the multimodel mean AMOC strengthened by approximately 10% from 1850–1985 in new simulations from the 6th Coupled Model Intercomparison Project (CMIP6), a larger change than was seen in CMIP5. Across the models, the strength of the AMOC trend up to 1985 is related to a proxy for the strength of the aerosol forcing. Therefore, the multimodel difference is a result of stronger anthropogenic aerosol forcing on average in CMIP6 than CMIP5, which is primarily due to more models including aerosol‐cloud interactions. However, observational constraints—including a historical sea surface temperature fingerprint and shortwave radiative forcing in recent decades—suggest that anthropogenic forcing and/or the AMOC response may be overestimated. The Atlantic Meridional Overturning Circulation (AMOC) is important in modulating climate change, but its past evolution is uncertainIn CMIP6 historical runs, the AMOC strengthens by ~10% as a response to increased forcing from aerosol indirect effects, unlike in CMIP5Observational constraints suggest that anthropogenic forcing and/or the AMOC response may be overestimated

The methods to quantify equilibrium climate sensitivity are still debated. We collect millennial‐length simulations of coupled climate models and show that the global mean equilibrium warming is higher than those obtained using extrapolation methods from shorter simulations. Specifically, 27 simulations with 15 climate models forced with a range of CO2concentrations show a median 17% larger equilibrium warming than estimated from the first 150 years of the simulations. The spatial patterns of radiative feedbacks change continuously, in most regions reducing their tendency to stabilizing the climate. In the equatorial Pacific, however, feedbacks become more stabilizing with time. The global feedback evolution is initially dominated by the tropics, with eventual substantial contributions from the mid‐latitudes. Time‐dependent feedbacks underscore the need of a measure of climate sensitivity that accounts for the degree of equilibration, so that models, observations, and paleo proxies can be adequately compared and aggregated to estimate future warming. Twenty‐seven simulations of 15 general circulation models are integrated to near equilibriumAll models simulate a higher equilibrium warming than predicted by using extrapolation methodsTropics and middle latitudes dominate the change of the feedback parameter on different time scales

Using volcanic sulfur dioxide emissions in an aerosol‐climate model, we derive a time series of global‐mean volcanic effective radiative forcing (ERF) from 1979 to 2015. For 2005–2015, we calculate a global multiannual mean volcanic ERF of −0.08 W/m2relative to the volcanically quiescent 1999–2002 period, due to a high frequency of small‐to‐moderate‐magnitude explosive eruptions after 2004. For eruptions of large magnitude such as 1991 Mt. Pinatubo, our model‐simulated volcanic ERF, which accounts for rapid adjustments including aerosol perturbations of clouds, is less negative than that reported in the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) that only accounted for stratospheric temperature adjustments. We find that, when rapid adjustments are considered, the relation between volcanic forcing and volcanic stratospheric optical depth (SAOD) is 13–21% weaker than reported in IPCC AR5 for large‐magnitude eruptions. Further, our analysis of the recurrence frequency of eruptions reveals that sulfur‐rich small‐to‐moderate‐magnitude eruptions with column heights ≥10 km occur frequently, with periods of volcanic quiescence being statistically rare. Small‐to‐moderate‐magnitude eruptions should therefore be included in climate model simulations, given the >50% chance of one or two eruptions to occur in any given year. Not all of these eruptions affect the stratospheric aerosol budget, but those that do increase the nonvolcanic background SAOD by ~0.004 on average, contributing ~50% to the total SAOD in the absence of large‐magnitude eruptions. This equates to a volcanic ERF of about −0.10 W/m2, which is about two thirds of the ERF from ozone changes induced by ozone‐depleting substances. We calculate the climatic effects of explosive volcanic eruptions between 1979 and 2015 using a more complex climate model simulation than has been used previously. This includes many of the chemical and physical processes that lead to the formation of volcanic aerosol. Volcanic aerosols are tiny airborne particles that are important for Earth's climate because they reflect sunlight and trap thermal infrared radiative energy. In line with previous studies, we find that the most powerful eruptions between 1979 and 2015 had a substantial cooling effect. However, we calculate that their effect on climate is about 20% weaker than previous estimates used by the Intergovernmental Panel on Climate Change (IPCC). In our model simulation this is mainly a result of the volcanic aerosol particles affecting ice clouds, making these clouds less transparent. We also find that it is very rare to have a period with relatively few notable explosive eruptions as was the case during 1996–2002. Furthermore, eruptions of small‐to‐moderate size occur frequently and decrease the transparency of the stratosphere by as much as all nonvolcanic sources of aerosol particles combined. These small‐sized volcanic eruptions therefore cause a small but noticeable surface cooling and so should be included in climate model simulations, which is rarely done. Small‐magnitude eruptions caused a global‐mean ERF of −0.08 W/m2during 2005–2015 relative to the volcanically quiescent 1999–2002 periodIn our model rapid adjustments act to reduce the total volcanic forcing per unit SAOD change by 13–21% for large‐magnitude eruptionsOn average, frequent small‐magnitude eruptions increase the nonvolcanic background SAOD by 0.004, equating to a volcanic ERF of −0.10 W/m2

Lists the largest office furniture companies in Saint Louis, Missouri as ranked by the number of employees in furniture division. Includes Color Art Office Interiors Inc.; Remanufactured Business Furniture; Warehouse of Fixtures; Corporate Interiors Inc.; WorkPlace Resource. INSET: Making the List.

Reports that Saint Louis, Missouri-based local sports and art agent Michael Barnes represented Phil Ozersky in selling Mark McGwire's number 70 home run baseball. Decision to represent the sellers of five other McGwire and Sammy Sosa home run balls; Windfall from the transactions; Barnes' plan to sell his firm Creative Properties Management Group; Proposal to concentrate on the business of auctioning collectibles.

Reports on the television advertisements by supporters and opponents of the concealed weapons proposal in Missouri. Advertising spending; Criteria in issuing firearm permits to citizens under the proposal; Financial resources of supporters and proponents.

Presents a list of the largest nonprofit residential medical care facilities in Missouri ranked according to the number of licensed beds in 1998. Includes Laclade Commons in Webster Groves; Mother of Perpetual Help in Saint Louis; Autumn View Gardens in Ellsville. INSET: Making the List.

Presents a list of the largest nursing homes in Missouri ranked according to the number of licensed beds in 1998. Includes Northview Village Nursing Home in Saint Louis; Compton Terrace Care Center in Saint Louis; Delmar Gardens West Nursing & Rehabilitation Center in Chesterfield. INSET: Making the List.

Ranks the largest commercial real estate firms in Saint Louis, Missouri, based on number of agents.

Provides information on the largest home builders in the Saint Louis, Missouri area, ranked by 1998 local home-building revenue. Number of homes sold in 1998; Geographic concentration; Number of full-time employees; Percentage of work subcontracted out; Includes Jones Co.; Whittaker Construction Inc.; Hayden Homes Inc.

Provides information on the largest general contractors in the Saint Louis, Missouri area, ranked by 1998 companywide revenue. Number of local employees; Percentage of work subcontracted to other companies; Sample of local projects; Includes Svendrup Corp.; Fru-Con Construction Corp.; Fred Weber Inc.