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1. A Dynamically Consistent ENsemble of Temperature at the Earth surface since 1850 from the DCENT dataset

   https://doi.org/10.1038/s41597-024-03742-x  

   Chan, Duo; Gebbie, Geoffrey; Huybers, Peter; Kent, Elizabeth C (August 2024, Scientific Data)

   Abstract Accurate historical records of Earth’s surface temperatures are central to climate research and policy development. Widely-used estimates based on instrumental measurements from land and sea are, however, not fully consistent at either global or regional scales. To address these challenges, we develop the Dynamically Consistent ENsemble of Temperature (DCENT), a 200-member ensemble of monthly surface temperature anomalies relative to the 1982–2014 climatology. Each DCENT member starts from 1850 and has a 5° × 5° resolution. DCENT leverages several updated or recently-developed approaches of data homogenization and bias adjustments: an optimized pairwise homogenization algorithm for identifying breakpoints in land surface air temperature records, a physics-informed inter-comparison method to adjust systematic offsets in sea-surface temperatures recorded by ships, and a coupled energy balance model to homogenize continental and marine records. Each approach was published individually, and this paper describes a combined approach and its application in developing a gridded analysis. A notable difference of DCENT relative to existing temperature estimates is a cooler baseline for 1850–1900 that implies greater historical warming. 

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2. Emerging climate impact on carbon sinks in a consolidated carbon budget

   https://doi.org/10.1038/s41586-025-09802-5  

   Friedlingstein, Pierre; Le_Quéré, Corinne; O’Sullivan, Michael; Hauck, Judith; Landschützer, Peter; Luijkx, Ingrid T; Li, Hongmei; van_der_Woude, Auke; Schwingshackl, Clemens; Pongratz, Julia; et al (January 2026, Nature)

   Abstract Despite the adoption of the Paris Agreement 10 years ago, carbon dioxide (CO₂) emissions from burning fossil fuels continue to increase, pushing atmospheric CO₂levels to 423 ppm in 2024 and driving human-induced warming to 1.36 °C, within years of breaching the 1.5 °C limit^1,2. Accurate reporting of anthropogenic and natural CO₂sources and sinks is a prerequisite to tracking the effectiveness of climate policy and detecting carbon-sink responses to climate change. Yet notable mismatches between reported emissions and sinks have so far prevented confident interpretation of their trends and drivers¹. Here we present and integrate recent advances in observations and process understanding to address some long-standing issues in global carbon budget estimates. We show that the magnitude of the natural land sink is substantially smaller than previously estimated, whereas net emissions from anthropogenic land-use change are revised upwards¹. The ocean sink is 15% larger than the land sink, consistent with recent evidence from oceanic and atmospheric observations^3,4. Climate change reduces the efficiency of the sinks, particularly on land, contributing 8.3 ± 1.4 ppm to the atmospheric CO₂increase since 1960. The combined effects of climate change and deforestation have turned Southeast Asian and large parts of South American tropical forests from CO₂sinks to sources. This underscores the need to halt deforestation and limit warming to prevent further loss of carbon stored on land. Improved confidence in assessments of CO₂sources and sinks is fundamental for effective climate policy. 

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3. LEGA-C stellar population scaling relations: I. Chemo-archaeological downsizing trends at z ∼ 0.7

   https://doi.org/10.1051/0004-6361/202554922  

   Gallazzi, Anna R; Zibetti, Stefano; van_der_Wel, Arjen; Nersesian, Angelos; Kaushal, Yasha; Bezanson, Rachel; D’Eugenio, Francesco; Bell, Eric F; Leja, Joel; Scholz-Diaz, Laura; et al (April 2026, Astronomy & Astrophysics)

   We analysed the stellar population properties of a well-defined sample of 552 galaxies at redshift 0.6 < z < 0.77 drawn from the LEGA-C spectroscopic survey. This paper is the first of a series, and it is aimed at (i) presenting the catalogue of revised absorption indices for LEGA-C DR3 and of the inferred physical parameter estimates while describing their systematic uncertainties and at (ii) deriving benchmark scaling relations for the general massive galaxy population at intermediate redshift. We estimated light-weighted mean ages and stellar metallicities through careful analysis of key absorption features in the stellar continuum spectra of the galaxies coupled with photometry. The observables were interpreted in a Bayesian framework with a comprehensive library of model spectra based on stochastic star formation histories, chemical enrichment histories, and dust attenuations. We discuss various sources of systematic uncertainties within our method as well as systematic differences with results from other spectral fitting approaches. We derived volume-weighted scaling relations connecting light-weighted mean ages and stellar metallicities with galaxy stellar mass for the general galaxy population at ⟨z⟩ = 0.7 and masses > 10¹⁰ M_⊙. We find the downsizing trends observed in the local Universe to be already in place 6 Gyr ago. We also observe a bimodal distribution of light-weighted ages as a function of mass, transitioning around 10¹¹ M_⊙. Such a bimodality is not observed in the stellar metallicity-mass relation, which changes from a steep to a flat regime acrossM_* ∼ 10^10.8 M_⊙. Similar trends in age and metallicity also emerge as a function of velocity dispersion, but with a sharper transition from young to old around logσ_* = 2.3. Differences with respect to the trends as a function of stellar mass suggest that age is primarily dependent on velocity dispersion below and above the transition regime, while both the stellar mass and the depth of the total gravitational potential well (as traced by the velocity dispersion) contribute to stellar metallicity. We release the catalogues of revised absorption index measurements for LEGA-C DR3 used in this work and of the inferred stellar population physical parameters to public repositories. 

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4. The phototrophic purple non‐sulfur bacteria Rhodomicrobium spp. are novel chassis for bioplastic production

   https://doi.org/10.1111/1751-7915.14552  

   Conners, Eric M; Rengasamy, Karthikeyan; Ranaivoarisoa, Tahina; Bose, Arpita (August 2024, Microbial Biotechnology)

   Abstract Petroleum‐based plastics levy significant environmental and economic costs that can be alleviated with sustainably sourced, biodegradable, and bio‐based polymers such as polyhydroxyalkanoates (PHAs). However, industrial‐scale production of PHAs faces barriers stemming from insufficient product yields and high costs. To address these challenges, we must look beyond the current suite of microbes for PHA production and investigate non‐model organisms with versatile metabolisms. In that vein, we assessed PHA production by the photosynthetic purple non‐sulfur bacteria (PNSB)Rhodomicrobium vannieliiandRhodomicrobium udaipurense.We show that both species accumulate PHA across photo‐heterotrophic, photo‐hydrogenotrophic, photo‐ferrotrophic, and photo‐electrotrophic growth conditions, with either ammonium chloride (NH₄Cl) or dinitrogen gas (N₂) as nitrogen sources. Our data indicate that nitrogen source plays a significant role in dictating PHA synthesis, with N₂fixation promoting PHA production during photoheterotrophy and photoelectrotrophy but inhibiting production during photohydrogenotrophy and photoferrotrophy. We observed the highest PHA titres (up to 44.08 mg/L, or 43.61% cell dry weight) when cells were grown photoheterotrophically on sodium butyrate with N₂, while production was at its lowest during photoelectrotrophy (as low as 0.04 mg/L, or 0.16% cell dry weight). We also find that photohydrogenotrophically grown cells supplemented with NH₄Cl exhibit the highest electron yields – up to 58.89% – while photoheterotrophy demonstrated the lowest (0.27%–1.39%). Finally, we highlight superior electron conversion and PHA production compared to a related PNSB,Rhodopseudomonas palustrisTIE‐1. This study illustrates the value of studying non‐model organisms likeRhodomicrobiumfor sustainable PHA production and indicates future directions for exploring PNSB metabolisms. 

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5. Global and Regional Discrepancies between Early-Twentieth-Century Coastal Air and Sea Surface Temperature Detected by a Coupled Energy-Balance Analysis

   https://doi.org/10.1175/JCLI-D-22-0569.1  

   Chan, Duo; Gebbie, Geoffrey; Huybers, Peter (April 2023, Journal of Climate)

   Abstract A major uncertainty in reconstructing historical sea surface temperature (SST) before the 1990s involves correcting for systematic offsets associated with bucket and engine-room intake temperature measurements. A recent study used a linear scaling of coastal station-based air temperatures (SATs) to infer nearby SSTs, but the physics in the coupling between SATs and SSTs generally gives rise to more complex regional air–sea temperature differences. In this study, an energy-balance model (EBM) of air–sea thermal coupling is adapted for predicting near-coast SSTs from coastal SATs. The model is shown to be more skillful than linear-scaling approaches through cross-validation analyses using instrumental records after the 1960s and CMIP6 simulations between 1880 and 2020. Improved skill primarily comes from capturing features reflecting air–sea heat fluxes dominating temperature variability at high latitudes, including damping high-frequency wintertime SAT variability and reproducing the phase lag between SSTs and SATs. Inferred near-coast SSTs allow for intercalibrating coastal SAT and SST measurements at a variety of spatial scales. The 1900–40 mean offset between the latest SST estimates available from the Met Office (HadSST4) and SAT-inferred SSTs range between −1.6°C (95% confidence interval: [−1.7°, −1.4°C]) and 1.2°C ([0.8°, 1.6°C]) across 10° × 10° grids. When further averaged along the global coastline, HadSST4 is significantly colder than SAT-inferred SSTs by 0.20°C ([0.07°, 0.35°C]) over 1900–40. These results indicate that historical SATs and SSTs involve substantial inconsistencies at both regional and global scales. Major outstanding questions involve the distribution of errors between our intercalibration model and instrumental records of SAT and SST as well as the degree to which coastal intercalibrations are informative of global trends. Significance Statement To evaluate the consistency of instrumental surface temperature estimates before the 1990s, we develop a coupled energy-balance model to intercalibrate measurements of sea surface temperature (SST) and station-based air temperature (SAT) near global coasts. Our model captures geographically varying physical regimes of air–sea coupling and outperforms existing methods in inferring regional SSTs from SAT measurements. When applied to historical temperature records, the model indicates significant discrepancies between inferred and observed SSTs at both global and regional scales before the 1960s. Our findings suggest remaining data issues in historical temperature archives and opportunities for further improvements. 

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