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Abstract In this work, we examine connections between patterns of future Greenland precipitation and large-scale atmospheric circulation changes over the Northern Hemisphere. In the last three decades of the 21st century, CMIP5 and CMIP6 ensemble mean precipitation significantly decreases over the northern part of the North Atlantic Ocean with respect to 1951–1980. This drying signal extends from the ocean to the southeastern margin of Greenland. The 500 hPa geopotential height change shows a clear pattern including a widespread increase across the Arctic with a negative anomaly centered over Iceland and surrounding regions. To identify the mechanisms linking atmospheric circulation variability with Greenland precipitation, we perform a singular value decomposition (SVD) and center of action (COA) analysis. We find that a northeastward shift of the Icelandic Low (IL) under the SSP5‐8.5 warming scenario leads to the drying signal found in southeast Greenland. This implies that the IL location will have a strong influence on precipitation changes over southeast Greenland in the future, impacting projections of Greenland ice sheet surface mass balance.

High-frequency electrical stimulation (HFS) of the skin using a multi-pin electrode activating epidermal nociceptors is used to explore spinal central sensitization in humans. Most previous studies applied HFS to the volar forearm. To prepare for clinical applications in which HFS could be applied to different body sites, this study compared the secondary hyperalgesia induced by stimulation of the foot dorsum vs. the forearm in 32 healthy volunteers. HFS consisted in five 1-s trains of 100 Hz pulses (inter-train interval: 10 s; intensity: 20x detection threshold) delivered via a novel electrode optimized for stimulation of different body sites (ten 0.25 mm pins in a 5-mm circle). Pinprick sensitivity was assessed before HFS and 30-240 minutes after HFS, at the treated site and the corresponding contralateral site. The area of hyperalgesia was quantified. HFS to the foot induced a significant increase in pinprick sensitivity of the surrounding skin, similar in magnitude to the increase at the forearm, and decaying similarly over time (half-lives 150 vs. 221 min). The radius of secondary hyperalgesia was smaller at the foot (22 mm) compared to the forearm (38 mm, p

Reducing piglet mortality and congenital defects is vital in pig production, as these traits substantially impact piglet welfare and lead to significant production losses. Additionally, piglets born with congenital defects often demand extra attention and resources from pig farmers. Nowadays, most breeders have shifted towards a more balanced breeding within their maternal pig lines, with a focus on both reproductive capacity and survival traits. However, few studies have investigated the influence of paternal sire genetics on crossbred piglets’ vitality and congenital defects. In this study, we evaluated the impact of an ongoing Piétrain sire breeding program on these traits in crossbred piglets that started in 2019. This study was based on two unique datasets with litter records collected between 2016 and 2024 on four independent commercial sow farms. The first dataset was collected by the breeding organization and consisted of 12,010 crossbred litters (Piétrain sire, hybrid dam; two farms) scored on piglets’ vitality, number of piglets with porcine congenital splay leg syndrome and scrotal hernia, pre-weaning mortality and the number of piglets born death. A second dataset (5,380 crossbred litters; two farms) was collected by ILVO (Flanders Research Institute for Agriculture, Fisheries and Food), using 426 Piétrain boars common to the first dataset of the breeding organization. Using a genetic sire-dam model, the studied traits were estimated to be lowly heritable (h2 = 5.2 to 15.6%). Moreover, vitality scores were genetically moderately correlated with preweaning mortality (rg=-0.59) and porcine congenital splay leg syndrome (rg=-0.52). Evolutions of phenotypic records and estimated breeding values since the start of the breeding program indicate a positive impact on piglet survival and prevalence of porcine congenital splay leg syndrome. The observed prevalence for porcine congenital splay leg syndrome roughly halved from ±1% in 2019 to ±0.5% in 2024, while for pre-weaning mortality, the observed prevalence dropped from ±17% in 2019 to ±14% in 2024. A joint analysis of the datasets showed a moderate to high genetic correlation (rg=0.52 to 0.84) for porcine congenital splay leg syndrome and pre-weaning mortality, indicating the translatability of estimated breeding values for terminal sires to new farms, specifically for these traits. In conclusion, these results show that paternal pig breeding programs can be effective in substantially improving piglets’ vitality while reducing porcine congenital splay leg syndrome and pre-weaning mortality. Due to the pressing societal demands for more animal welfare and the economic impact of these traits, we show other pig breeding companies the important role of paternal pig genetics towards improved piglet vitality and a reduction of congenital defects.

The next version of the polar Regional Atmospheric Climate Model (referred to as RACMO2.4p1) is presented in this study. The principal update includes embedding of the package of physical parameterizations of the Integrated Forecast System (IFS) cycle 47r1. This constitutes changes in the precipitation, convection, turbulence, aerosol and surface schemes and includes a new cloud scheme with more prognostic variables and a dedicated lake model. Furthermore, the standalone IFS radiation physics module ecRad is incorporated into RACMO, and a multilayer snow module for non-glaciated regions is introduced. Other updates involve the introduction of a fractional land–ice mask, new and updated climatological data sets (such as aerosol concentrations and leaf area index), and the revision of several parameterizations specific to glaciated regions. As a proof of concept, we show first results for Greenland, Antarctica and a region encompassing the Arctic. By comparing the results with observations and the output from the previous model version (RACMO2.3p3), we show that the model performs well regarding the surface mass balance, surface energy balance, temperature, wind speed, cloud content and snow depth. The advection of snow hydrometeors strongly impacts the ice sheet's local surface mass balance, particularly in high-accumulation regions such as southeast Greenland and the Antarctic Peninsula. We critically assess the model output and identify some processes that would benefit from further model development.

Elevation changes of the Antarctic Ice Sheet (AIS) related to surface mass balance and firn processes vary strongly in space and time. Their subdecadal natural variability is large and hampers the detection of long-term climate trends. Firn models or satellite altimetry observations are typically used to investigate such firn thickness changes. However, there is a large spread among firn models. Further, they do not fully explain observed firn thickness changes, especially on smaller spatial scales. Reconciled firn thickness variations will facilitate the detection of long-term trends from satellite altimetry; the resolution of the spatial patterns of such trends; and, hence, their attribution to the underlying mechanisms. This study has two objectives. First, we quantify interannual Antarctic firn thickness variations on a 10 km grid scale. Second, we characterise errors in both the altimetry products and firn models. To achieve this, we jointly analyse satellite altimetry and firn modelling results in time and space. We use the timing of firn thickness variations from firn models and the satellite-observed amplitude of these variations to generate a combined product (“adjusted firn thickness variations”) over the AIS for 1992–2017. The combined product characterises spatially resolved variations better than either firn models alone or altimetry alone. It provides a higher resolution and a more precise spatial distribution of the variations compared to model-only solutions and eliminates most of the altimetry errors compared to altimetry-only solutions. Relative uncertainties in basin-mean time series of the adjusted firn thickness variations range from 20 % to 108 %. At the grid cell level, relative uncertainties are higher, with median values per basin in the range of 54 % to 186 %. This is due to the uncertainties in the large and very dry areas of central East Antarctica, especially over large megadune fields, where the low signal-to-noise ratio poses a challenge for both models and altimetry to resolve firn thickness variations. A large part of the variance in the altimetric time series is not explained by the adjusted firn thickness variations. Analysis of the altimetric residuals indicate that they contain firn model errors, such as firn signals not captured by the models, and altimetry errors, such as time-variable radar penetration effects and errors in intermission calibration. This highlights the need for improvements in firn modelling and altimetry analysis.

The Antarctic firn layer provides pore space in which an estimated 94 % to 96 % of the surface melt refreezes or is retained as liquid water. Future depletion of firn pore space by increased surface melt, densification and formation of low-permeability ice slabs can potentially lead to meltwater ponding, hydrofracturing and ice-shelf disintegration. Here, we investigate the 21st-century evolution of total firn air content (FAC) and accessible FAC (i.e. the pore space that meltwater can reach) across Antarctic ice shelves. We use the semi-empirical IMAU Firn Densification Model (IMAU-FDM) with an updated dynamical densification expression to cope with changing climate forcing. The firn model is forced by general circulation model output of the Community Earth System Model version 2 (CESM2) for three climate emission scenarios (SSP1-2.6, SSP2-4.5 and SSP5-8.5), dynamically downscaled to a 27 km horizontal resolution by the Regional Atmospheric Climate Model version 2.3p2 (RACMO2.3p2). To estimate accessible FAC, we prescribe a relationship between ice-slab thickness and permeability. In our simulations, ice shelves on the Antarctic Peninsula and the Roi Baudouin Ice Shelf in Dronning Maud Land are particularly vulnerable to total FAC depletion (> 50 % decrease by 2100), even for low-emission (SSP1-2.6) and intermediate-emission (SSP2-4.5) scenarios. In the high-emission (SSP5-8.5) scenario in particular, the formation of ice slabs further reduces accessible FAC on ice shelves with low accumulation rates (current rates of < 500 mmw.e.yr-1), including many East Antarctic ice shelves and the Filchner–Ronne, Ross, Pine Island and Larsen C ice shelves. These results underline the potentially large vulnerability of low-accumulation ice shelves to firn air depletion through ice-slab formation.

Different assisted recovery techniques have been developed to enhance the safety and quality of equine recoveries. This case series evaluates the recovery of horses using an air-inflated pillow (Equi-lift®). With owner consent, the following data were collected from 19 horses undergoing open castration and 21 horses where a difficult recovery was anticipated: age, bodyweight, procedure, anaesthetic protocol, time required for proper positioning in the Equi-lift®, time to extubation, time to standing, number of attempts to stand, number of stimuli, behaviour during recumbency/first attempts, and overall impression. Horses were 1–24 years old, with a bodyweight of 483.5 ± 106.8 kg. The median time to properly position a horse into the system was 6 min (range: 1–15 min). The recovery duration was 42 min (range: 21–181 min), with a median of 4 attempts (range: 1–12 attempts) and 1 stimulus (range: 0–10) before fully standing. Recovery was calm in most horses (32/40) and moderate (with signs of anxiety and/or excitation) in 3/40 horses. In five horses, the use of this technique was discontinued. All horses recovered without any injuries or other immediate postoperative complications. In conclusion, this recovery technique shows promising results, but further studies are needed to confirm the findings.

Surface melt on the Greenland ice sheet has been increasing in intensity and extent over the last decades due to Arctic atmospheric warming. Surface melt depends on the surface energy balance, which includes the atmospheric forcing but also the thermal budget of the snow, firn and ice near the ice sheet surface. The temperature of the ice sheet subsurface has been used as an indicator of the thermal state of the ice sheet's surface. Here, we present a compilation of 4612 measurements of firn and ice temperature at 10 m below the surface (T10 m) across the ice sheet, spanning from 1912 to 2022. The measurements are either instantaneous or monthly averages. We train an artificial neural network model (ANN) on 4597 of these point observations, weighted by their relative representativity, and use it to reconstruct T10 m over the entire Greenland ice sheet for the period 1950–2022 at a monthly timescale. We use 10-year averages and mean annual values of air temperature and snowfall from the ERA5 reanalysis dataset as model input. The ANN indicates a Greenland-wide positive trend of T10 m at 0.2 ∘C per decade during the 1950–2022 period, with a cooling during 1950–1985 (−0.4 ∘C per decade) followed by a warming during 1985–2022 (+0.7 ∘ per decade). Regional climate models HIRHAM5, RACMO2.3p2 and MARv3.12 show mixed results compared to the observational T10 m dataset, with mean differences ranging from −0.4 ∘C (HIRHAM) to 1.2 ∘C (MAR) and root mean squared differences ranging from 2.8 ∘C (HIRHAM) to 4.7 ∘C (MAR). The observation-based ANN also reveals an underestimation of the subsurface warming trends in climate models for the bare-ice and dry-snow areas. The subsurface warming brings the Greenland ice sheet surface closer to the melting point, reducing the amount of energy input required for melting. Our compilation documents the response of the ice sheet subsurface to atmospheric warming and will enable further improvements of models used for ice sheet mass loss assessment and reduce the uncertainty in projections.

Recurring polarimetric radar signatures in supercells include deep and persistent differential reflectivity (ZDR) columns, hail inferred in low-level scans, and the ZDR arc signature. Prior investigations of supercell polarimetric signatures reveal positive correlations between the ZDR column depth and cross-sectional area and quantitative characteristics of the radar reflectivity field. This study expands upon prior work by examining temporal associations between supercell polarimetric radar signatures, incorporating a dataset of relatively discrete, right-moving supercells from the continental United States observed by the Weather Surveillance Radar 1988-Doppler (WSR-88D) network. Cross-correlation coefficients were calculated between the ZDR column area and depth and the base-scan hail area, ZDR arc area, and mean ZDR arc value. These correlation values were computed with a positive and negative lag time of up to 45 min. Results of the lag correlation analysis are consistent with prior observations indicative of storm cycling, including temporal associations between ZDR columns and inferred hail signatures/ZDR arcs in both tornadic and nontornadic supercells, but were most pronounced in tornadic storms.

Abstract Antarctic ice sheet (AIS) mass loss is predominantly driven by increased solid ice discharge, but its variability is governed by surface processes. Snowfall fluctuations control the surface mass balance (SMB) of the grounded AIS, while meltwater ponding can trigger ice shelf collapse potentially accelerating discharge. Surface processes are essential to quantify AIS mass change, but remain poorly represented in climate models typically running at 25-100 km resolution. Here we present SMB and surface melt products statistically downscaled to 2 km resolution for the contemporary climate (1979-2021) and low, moderate and high-end warming scenarios until 2100. We show that statistical downscaling modestly enhances contemporary SMB (3%), which is sufficient to reconcile modelled and satellite mass change. Furthermore, melt strongly increases (46%), notably near the grounding line, in better agreement with in-situ and satellite records. The melt increase persists by 2100 in all warming scenarios, revealing higher surface melt rates than previously estimated.

As climate change intensifies, heat stress mitigation for pigs becomes more important. Trials involving induced heat waves are useful to test several measures (e.g. reduced stocking density) at a faster rate, but only when accurately evaluated and validated. In the present study, we investigated the suitability of an artificial heating protocol at different pig weights (experiment 1). The impact of different stocking densities on fattening pigs during an artificial heat wave (experiment 2) was also investigated. Experiment 1: Forty 20-week-old pigs weighing 96.5 ± 7.3 kg (W100) and forty 17-week-old pigs weighing 72.7 ± 9.9 kg (W70) were housed in two compartments. An artificial heat wave (heat load) was induced for 3 days. During 3-day periods before, during and after the heat load, physiological parameters (respiration rate (RR), rectal temperature (Trectal), skin temperature (Tskin) and behavior) were measured and average daily feed intake was observed. Ambient temperature, relative humidity and temperature-humidity index (THI) were monitored. Experiment 2: A total of 150 fattening pigs were randomly divided into three treatment groups: SD1.3 (1.3 m2/pig), SD1.0 (1.0 m2/pig) and SD0.8 (0.8 m2/pig). All pens had a total pen surface of 4.88 m2, corresponding with 4, 5 and 6 fattening pigs in the SD1.3, SD1.0 and SD0.8 groups, respectively. The heat load was induced for 7 days on week 21. Respiration rate and Trectal were observed as in experiment 1. Average daily gain and average daily feed intake were also noted. During the heat load, THI reached ≥ 75 (78.4 (experiment 1) and 78.6 (experiment 2)), even when relative humidity decreased to ± 45%. Every physiological parameter showed significant increases during the heat load. The prolonged heating protocol in experiment 2 also provoked significant decreases in average daily feed intake (15%) and average daily gain (19%) for all groups. Weight within the studied range of 70–100 kg did not have a significant impact on any of the parameters. However, Tskin was affected by both weight and heat load (P

The impact of pork production on global livestock’s greenhouse gas emissions is substantial. Understanding the factors influencing these emissions is crucial in achieving a more sustainable pig husbandry. In two independent experiments, the impact of slaughter weight on the carbon footprint (CFP) of pig feed intake (CFPFI) was evaluated for growing-finishing pigs of different sexes (entire males (EM), barrows (BA), immunocastrates (IC) and gilts (GI)). In experiment 1 118 animals were raised individually in experimental conditions. In experiment 2 384 animals were housed in group (four pigs per pen), in controlled commercial farm circumstances. All animals were fed ad libitum in a three-phase feeding regime and slaughtered at different BW, ranging from 110 to 148 kg (experiment 1) and from 99 to 138 kg (experiment 2). When only the fattening period was considered, the CFPFI was expressed per kg carcass growth. When the production of piglets was also taken into account, the CFPFI was calculated per kg carcass weight. For all sexes, the heavier the pig, the higher the CFPFI per kg carcass growth (P

The land ice contribution to global mean sea level rise has not yet been predicted1 using 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 scenarios9 and climate models10, and could not fully explore known uncertainties. Here we estimate probability distributions for these projections under the new scenarios11,12 using 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.

Associated commentary:. Fillingim RB. Redefining sensitization could be a sensitive issue. PAIN Rep 2024;9:e1126.

We study the meteorological drivers of melt at two glaciers in Taylor Valley, Antarctica, using 22 years of weather station observations and surface energy fluxes. The glaciers are located only 30 km apart, but have different local climates; Taylor Glacier is generally drier and windier than Commonwealth Glacier, which receives more snowfall due to its proximity to the coast. Commonwealth Glacier shows more inter-annual melt variability, explained by variable albedo due to summer snowfall events. A significant increase in surface melt at Commonwealth Glacier is associated with a decrease in summer minimum albedo. Inter-annual variability in melt at both glaciers is linked to degree-days above freezing during föhn events, occurring more frequently at Taylor Glacier. At Taylor Glacier melt occurs most often with positive air temperatures, but föhn conditions also favour sublimation, which cools the surface and prevents melt for the majority of the positive air temperatures. At Commonwealth Glacier, most of the melt instead occurs with sub-zero air temperatures, driven by strong solar radiative heating. Future melt at Taylor Glacier will likely be more sensitive to changes in föhn events, while Commonwealth Glacier will be impacted more by changes in near coastal weather, where moisture inputs can drive cloud cover, snowfall and change albedo.

Accurately quantifying all the components of the surface energy balance (SEB) is a prerequisite for the reliable estimation of surface melt and the surface mass balance over ice and snow. This study quantifies the SEB closure by comparing the energy available for surface melt, determined from continuous measurements of radiative fluxes and turbulent heat fluxes, to the surface ablation measured on the Greenland ice sheet between 2003 and 2023. We find that the measured daily energy available for surface melt exceeds the observed surface melt by on average 18 ± 30 W m−2 for snow and 12 ± 54 W m−2 for ice conditions (mean ± SD), which corresponds to 46 and 10% of the average energy available for surface melt, respectively. When the surface is not melting, the daily SEB is on average closed within 5 W m−2. Based on the inter-comparison of different ablation sensors and radiometers installed on different stations, and on the evaluation of modelled turbulent heat fluxes, we conclude that measurement uncertainties prevent a better daily to sub-daily SEB closure. These results highlight the need and challenges in obtaining accurate long-term in situ SEB observations for the proper evaluation of climate models and for the validation of remote sensing products.

The retreat and acceleration of Greenland glaciers since the mid-1990s have been attributed to the enhanced intrusion of warm Atlantic Waters (AW) into fjords, but this assertion has not been quantitatively tested on a Greenland-wide basis or included in models. Here, we investigate how AW influenced retreat at 226 marine-terminating glaciers using ocean modeling, remote sensing, and in situ observations. We identify 74 glaciers in deep fjords with AW controlling 49% of the mass loss that retreated when warming increased undercutting by 48%. Conversely, 27 glaciers calving on shallow ridges and 24 in cold, shallow waters retreated little, contributing 15% of the loss, while 10 glaciers retreated substantially following the collapse of several ice shelves. The retreat mechanisms remain undiagnosed at 87 glaciers without ocean and bathymetry data, which controlled 19% of the loss. Ice sheet projections that exclude ocean-induced undercutting may underestimate mass loss by at least a factor of 2.

Firn simulations are essential for understanding Antarctic ice sheet mass change, as they enable us to convert satellite altimetry observed volume changes to mass changes and column thickness to ice thickness and to quantify the meltwater buffering capacity of firn. Here, we present and evaluate a simulation of the contemporary Antarctic firn layer using the updated semi-empirical IMAU Firn Densification Model (IMAU-FDM) for the period 1979–2020. We have improved previous fresh-snow density and firn compaction parameterizations and used updated atmospheric forcing. In addition, the model has been calibrated and evaluated using 112 firn core density observations across the ice sheet. We found that 62 % of the seasonal and 67 % of the decadal surface height variability are due to variations in firn air content rather than firn mass. Comparison of simulated surface elevation change with a previously published multi-mission altimetry product for the period 2003–2015 shows that performance of the updated model has improved, notably in Dronning Maud Land and Wilkes Land. However, a substantial trend difference (>10 cm yr−1) remains in the Antarctic Peninsula and Ellsworth Land, mainly caused by uncertainties in the spin-up forcing. By estimating previous climatic conditions from ice core data, these trend differences can be reduced by 38 %.

Ice losses from the Greenland and Antarctic ice sheets have accelerated since the 1990s, accounting for a significant increase in the global mean sea level. Here, we present a new 29-year record of ice sheet mass balance from 1992 to 2020 from the Ice Sheet Mass Balance Inter-comparison Exercise (IMBIE). We compare and combine 50 independent estimates of ice sheet mass balance derived from satellite observations of temporal changes in ice sheet flow, in ice sheet volume, and in Earth's gravity field. Between 1992 and 2020, the ice sheets contributed 21.0±1.9 mm to global mean sea level, with the rate of mass loss rising from 105 Gt yr−1 between 1992 and 1996 to 372 Gt yr−1 between 2016 and 2020. In Greenland, the rate of mass loss is 169±9 Gt yr−1 between 1992 and 2020, but there are large inter-annual variations in mass balance, with mass loss ranging from 86 Gt yr−1 in 2017 to 444 Gt yr−1 in 2019 due to large variability in surface mass balance. In Antarctica, ice losses continue to be dominated by mass loss from West Antarctica (82±9 Gt yr−1) and, to a lesser extent, from the Antarctic Peninsula (13±5 Gt yr−1). East Antarctica remains close to a state of balance, with a small gain of 3±15 Gt yr−1, but is the most uncertain component of Antarctica's mass balance. The dataset is publicly available at https://doi.org/10.5285/77B64C55-7166-4A06-9DEF-2E400398E452 (IMBIE Team, 2021).

The Community Land Model (CLM) is the land component of the Community Earth System Model (CESM) and is used in several global and regional modeling systems. In this paper, we introduce model developments included in CLM version 5 (CLM5), which is the default land component for CESM2. We assess an ensemble of simulations, including prescribed and prognostic vegetation state, multiple forcing data sets, and CLM4, CLM4.5, and CLM5, against a range of metrics including from the International Land Model Benchmarking (ILAMBv2) package. CLM5 includes new and updated processes and parameterizations: (1) dynamic land units, (2) updated parameterizations and structure for hydrology and snow (spatially explicit soil depth, dry surface layer, revised groundwater scheme, revised canopy interception and canopy snow processes, updated fresh snow density, simple firn model, and Model for Scale Adaptive River Transport), (3) plant hydraulics and hydraulic redistribution, (4) revised nitrogen cycling (flexible leaf stoichiometry, leaf N optimization for photosynthesis, and carbon costs for plant nitrogen uptake), (5) global crop model with six crop types and time-evolving irrigated areas and fertilization rates, (6) updated urban building energy, (7) carbon isotopes, and (8) updated stomatal physiology. New optional features include demographically structured dynamic vegetation model (Functionally Assembled Terrestrial Ecosystem Simulator), ozone damage to plants, and fire trace gas emissions coupling to the atmosphere. Conclusive establishment of improvement or degradation of individual variables or metrics is challenged by forcing uncertainty, parametric uncertainty, and model structural complexity, but the multivariate metrics presented here suggest a general broad improvement from CLM4 to CLM5.

Abstract. In this study, the resolution dependence of the simulated Greenland ice sheet surface mass balance (GrIS SMB) in the variable-resolution Community EarthSystem Model (VR-CESM) is investigated. Coupled atmosphere–land simulationsare performed on two regionally refined grids over Greenland at0.5∘ (∼55 km) and 0.25∘ (∼28 km), maintaininga quasi-uniform resolution of 1∘ (∼111 km) over the rest ofthe globe. On the refined grids, the SMB in the accumulation zone issignificantly improved compared to airborne radar and in situ observations,with a general wetting (more snowfall) at the margins and a drying (lesssnowfall) in the interior GrIS. Total GrIS precipitation decreases withresolution, which is in line with best-available regional climate modelresults. In the ablation zone, CESM starts developing a positive SMB biaswith increased resolution in some basins, notably in the east and the north.The mismatch in ablation is linked to changes in cloud cover in VR-CESM, anda reduced effectiveness of the elevation classes subgrid parametrization inCESM. Overall, our pilot study introduces VR-CESM as a new tool in the cryospheric sciences, which could be used todynamically downscale SMB in scenario simulations and to force dynamical icesheet models through the CESM coupling framework.

We reconstruct the mass balance of the Greenland Ice Sheet using a comprehensive survey of thickness, surface elevation, velocity, and surface mass balance (SMB) of 260 glaciers from 1972 to 2018. We calculate mass discharge, D, into the ocean directly for 107 glaciers (85% of D) and indirectly for 110 glaciers (15%) using velocity-scaled reference fluxes. The decadal mass balance switched from a mass gain of +47 ± 21 Gt/y in 1972-1980 to a loss of 51 ± 17 Gt/y in 1980-1990. The mass loss increased from 41 ± 17 Gt/y in 1990-2000, to 187 ± 17 Gt/y in 2000-2010, to 286 ± 20 Gt/y in 2010-2018, or sixfold since the 1980s, or 80 ± 6 Gt/y per decade, on average. The acceleration in mass loss switched from positive in 2000-2010 to negative in 2010-2018 due to a series of cold summers, which illustrates the difficulty of extrapolating short records into longer-term trends. Cumulated since 1972, the largest contributions to global sea level rise are from northwest (4.4 ± 0.2 mm), southeast (3.0 ± 0.3 mm), and central west (2.0 ± 0.2 mm) Greenland, with a total 13.7 ± 1.1 mm for the ice sheet. The mass loss is controlled at 66 ± 8% by glacier dynamics (9.1 mm) and 34 ± 8% by SMB (4.6 mm). Even in years of high SMB, enhanced glacier discharge has remained sufficiently high above equilibrium to maintain an annual mass loss every year since 1998.

The McMurdo Dry Valleys (MDV) are a polar desert, where glacial melt is the main source of water to streams and the ecosystem. Summer air temperatures are typically close to zero, and therefore foehn events can have a large impact on the meltwater production. A 14-month record of automatic weather station (AWS) data on Joyce Glacier is used to force a 1D surface energy balance model to study the impact of foehn events on the energy balance. AWS data and output of the Antarctic Mesoscale Prediction System (AMPS) on a 1.7 km grid are used to detect foehn events at the AWS site. Foehn events at Joyce Glacier occur under the presence of cyclones over the Ross Sea. The location of Joyce Glacier on the leeward side of the Royal Society Range during these synoptic events causes foehn warming through isentropic drawdown. This mechanism differs from the foehn warming through gap flow that was earlier found for other regions in the MDV and highlights the complex interaction of synoptic flow with local topography of the MDV. Shortwave radiation is the primary control on melt at Joyce Glacier, and melt often occurs with subzero air temperatures. During foehn events, melt rates are enhanced, contributing to 23 % of the total annual melt. Foehn winds cause a switch from a diurnal stability regime in the atmospheric surface layer to a continuous energy input from sensible heat flux throughout the day. The sensible heating during foehn, through an increase in turbulent mixing resulting from gustier and warmer wind conditions, is largely compensated for by extra heat losses through sublimation. Melt rates are enhanced through an additional energy surplus from a reduced albedo during foehn.

Greenland firn, the layer of compressed snow that today covers 90% of the ice sheet, currently retains half of the meltwater through refreezing. Here the authors use climate simulations to predict that refreezing in Greenland firn could peak at around 2130 and decline thereafter, rapidly increasing ice sheet mass loss and sea level rise.

Abstract Greenland rainfall has come into focus as a climate change indicator and from a variety of emerging cryospheric impacts. This study first evaluates rainfall in five state‐of‐the‐art numerical prediction systems (NPSs) (CARRA, ERA5, NHM‐SMAP, RACMO, MAR) using in situ rainfall data from two regions spanning from land onto the ice sheet. The new EU Copernicus Climate Change Service (C3S) Arctic Regional ReAnalysis (CARRA), with a relatively fine (2.5 km) horizontal grid spacing and extensive within‐model‐domain observational initialization, has the lowest average bias and highest explained variance relative to the field data. ERA5 inland wet bias versus CARRA is consistent with the field data and other research and is presumably due to more ERA5 topographic smoothing. A CARRA climatology 1991–2021 has rainfall increasing by more than one‐third for the ice sheet and its peripheral ice masses. CARRA and in situ data illuminate extreme (above 300 mm per day) local rainfall episodes. A detailed examination CARRA data reveals the interplay of mass conservation that splits flow around southern Greenland and condensational buoyancy generation that maintains along‐flow updraft ‘rapids’ 2 km above sea level, which produce rain bands within an atmospheric river interacting with Greenland. CARRA resolves gravity wave oscillations that initiate as a result of buoyancy offshore, which then amplify from terrain‐forced uplift. In a detailed case study, CARRA resolves orographic intensification of rainfall by up to a factor of four, which is consistent with the field data.

The firn layer that covers 90 % of the Greenland ice sheet (GrIS) plays an important role in determining the response of the ice sheet to climate change. Meltwater can percolate into the firn layer and refreeze at greater depths, thereby temporarily preventing mass loss. However, as global warming leads to increasing surface melt, more surface melt may refreeze in the firn layer, thereby reducing the capacity to buffer subsequent episodes of melt. This can lead to a tipping point in meltwater runoff. It is therefore important to study the evolution of the Greenland firn layer in the past, present and future. In this study, we present the latest version of our firn model, IMAU-FDM (Firn Densification Model) v1.2G, with an application to the GrIS. We improved the density of freshly fallen snow, the dry-snow densification rate and the firn's thermal conductivity using recently published parametrizations and by calibration to an extended set of observations of firn density, temperature and liquid water content at the GrIS. Overall, the updated model settings lead to higher firn air content and higher 10 m firn temperatures, owing to a lower density near the surface. The effect of the new model settings on the surface elevation change is investigated through three case studies located at Summit, KAN-U and FA-13. Most notably, the updated model shows greater inter- and intra-annual variability in elevation and an increased sensitivity to climate forcing.

Southern New England is frequently affected by cold season windstorms, in which primarily southerly winds can cause extensive damage. These events do not fuel the extensive media coverage that nor’easters and tropical events do, despite often being more destructive and disruptive. To gain understanding of the climatology and role of the synoptic-scale environment, we explore the behavior and characteristics of the 96 events with the highest magnitude observed surface wind (maximum gust, fastest mile, and hourly sustained wind) from 1965 to 2022. Results indicate that the highest frequency and magnitude of events is associated with a due southerly wind. In addition, anomalously mild, near-record breaking temperatures often coincide with these wind events. Composite plots show a synoptic pattern favoring a deep digging trough to the Gulf Coast and anomalous ridging over the East Coast of the United States, extending offshore into the western Atlantic. Several soundings from representative events show an anomalous low-level jet just above the surface and a well-mixed boundary layer, indicating the importance of downward momentum transport. [ABSTRACT FROM AUTHOR]

Simple Summary: The recovery phase is associated with many complications, such as fractures, luxations, etc. Despite advances in equine anaesthesia, the percentage of mortality and morbidity during this phase remains proportionally constant. Assisted recovery techniques have been developed to improve the safety and quality of recovery. The objective of this study was to describe the recovery when using a new technique, an air-inflated pillow (Equi-lift®, Waremme, Belgium). Because the horses are placed in a semi-standing position, it was hypothesized that it could reduce morbidity during recovery. Most horses showed a calm recovery; although, in some horses, the use of the system was discontinued due to different reasons. This indicates that a good case selection is essential when using this system. Further studies will be required to define these selection criteria. There were no direct complications observed during the use of this system. Different assisted recovery techniques have been developed to enhance the safety and quality of equine recoveries. This case series evaluates the recovery of horses using an air-inflated pillow (Equi-lift®). With owner consent, the following data were collected from 19 horses undergoing open castration and 21 horses where a difficult recovery was anticipated: age, bodyweight, procedure, anaesthetic protocol, time required for proper positioning in the Equi-lift®, time to extubation, time to standing, number of attempts to stand, number of stimuli, behaviour during recumbency/first attempts, and overall impression. Horses were 1–24 years old, with a bodyweight of 483.5 ± 106.8 kg. The median time to properly position a horse into the system was 6 min (range: 1–15 min). The recovery duration was 42 min (range: 21–181 min), with a median of 4 attempts (range: 1–12 attempts) and 1 stimulus (range: 0–10) before fully standing. Recovery was calm in most horses (32/40) and moderate (with signs of anxiety and/or excitation) in 3/40 horses. In five horses, the use of this technique was discontinued. All horses recovered without any injuries or other immediate postoperative complications. In conclusion, this recovery technique shows promising results, but further studies are needed to confirm the findings. [ABSTRACT FROM AUTHOR]

Reducing piglet mortality and congenital defects is vital in pig production, as these traits substantially impact piglet welfare and lead to significant production losses. Additionally, piglets born with congenital defects often demand extra attention and resources from pig farmers. Nowadays, most breeders have shifted towards a more balanced breeding within their maternal pig lines, with a focus on both reproductive capacity and survival traits. However, few studies have investigated the influence of paternal sire genetics on crossbred piglets' vitality and congenital defects. In this study, we evaluated the impact of an ongoing Piétrain sire breeding program on these traits in crossbred piglets that started in 2019. This study was based on two unique datasets with litter records collected between 2016 and 2024 on four independent commercial sow farms. The first dataset was collected by the breeding organization and consisted of 12,010 crossbred litters (Piétrain sire, hybrid dam; two farms) scored on piglets' vitality, number of piglets with porcine congenital splay leg syndrome and scrotal hernia, pre-weaning mortality and the number of piglets born death. A second dataset (5,380 crossbred litters; two farms) was collected by ILVO (Flanders Research Institute for Agriculture, Fisheries and Food), using 426 Piétrain boars common to the first dataset of the breeding organization. Using a genetic sire-dam model, the studied traits were estimated to be lowly heritable (h2 = 5.2 to 15.6%). Moreover, vitality scores were genetically moderately correlated with preweaning mortality (rg=-0.59) and porcine congenital splay leg syndrome (rg=-0.52). Evolutions of phenotypic records and estimated breeding values since the start of the breeding program indicate a positive impact on piglet survival and prevalence of porcine congenital splay leg syndrome. The observed prevalence for porcine congenital splay leg syndrome roughly halved from ±1% in 2019 to ±0.5% in 2024, while for pre-weaning mortality, the observed prevalence dropped from ±17% in 2019 to ±14% in 2024. A joint analysis of the datasets showed a moderate to high genetic correlation (rg=0.52 to 0.84) for porcine congenital splay leg syndrome and pre-weaning mortality, indicating the translatability of estimated breeding values for terminal sires to new farms, specifically for these traits. In conclusion, these results show that paternal pig breeding programs can be effective in substantially improving piglets' vitality while reducing porcine congenital splay leg syndrome and pre-weaning mortality. Due to the pressing societal demands for more animal welfare and the economic impact of these traits, we show other pig breeding companies the important role of paternal pig genetics towards improved piglet vitality and a reduction of congenital defects. [ABSTRACT FROM AUTHOR]