Low biodegradability of particulate organic carbon mobilized from thaw slumps on the Peel Plateau, NT, and possible chemosynthesis and sorption effects Biogeosciences DOI 10.5194/bg-19-1871-2022 1 July 2022 Permafrost thaw-driven landslides in the western Arctic are increasing organic carbon delivered to headwaters of drainage networks in the western Canadian Arctic by orders of magnitude. Through a series of laboratory experiments, we show that less than 10% of this organic carbon is likely to be mineralized to greenhouse gases during transport in these networks. Rather most of the organic carbon is likely destined for burial and sequestration for centuries to millennia. Read more
A stratospheric prognostic ozone for seamless Earth system models: performance, impacts and future Atmospheric Chemistry and Physics DOI 10.5194/acp-22-4277-2022 29 June 2022 The stratosphere is emerging as one of the keys to improve tropospheric weather and climate predictions. This study provides evidence of the role the stratospheric ozone layer plays in improving weather predictions at different timescales. Using a new ozone modelling approach suitable for high-resolution global models that provide operational forecasts from days to seasons, we find significant improvements in stratospheric meteorological fields and stratosphere–troposphere coupling. Read more
Comparing the transport-limited and ξ–q models for sediment transport Earth Surface Dynamics DOI 10.5194/esurf-10-301-2022 27 June 2022 By comparing two models for the transport of sediment, we find that they share a similar steady-state solution that adequately predicts the shape of most depositional systems made of a fan and an alluvial plain. The length of the fan is controlled by the size of the mountain drainage area feeding the sedimentary system and its slope by the incoming sedimentary flux. We show that the models differ in their transient behaviour to external forcing and are characterized by different response times. Read more
Uncertainty estimation with deep learning for rainfall–runoff modeling Hydrology and Earth System Sciences DOI 10.5194/hess-26-1673-2022 24 June 2022 This contribution evaluates distributional run-off predictions from deep-learning-based approaches. We propose a benchmarking setup and establish four strong baselines. The results show that accurate, precise, and reliable uncertainty estimation can be achieved with deep learning. Read more
Full latitudinal marine atmospheric measurements of iodine monoxide Atmospheric Chemistry and Physics DOI 10.5194/acp-22-4005-2022 22 June 2022 We have undertaken atmospheric iodine monoxide (IO) observations in the global marine boundary layer with a wide latitudinal coverage and sea surface temperature (SST) range. We conclude that atmospheric iodine is abundant over the Western Pacific warm pool, appearing as an iodine fountain, where ozone (O3) minima occur. Our study also found negative correlations between IO and O3 concentrations over IO maxima, which requires reconsideration of the initiation process of halogen activation. Read more
Arctic glaciers and ice caps through the Holocene:a circumpolar synthesis of lake-based reconstructions Climate of the Past DOI 10.5194/cp-18-579-2022 20 June 2022 This paper synthesizes 66 records of glacier variations over the Holocene from lake archives across seven Arctic regions. We find that summers only moderately warmer than today drove major environmental change across the Arctic in the early Holocene, including the widespread loss of glaciers. In comparison, future projections of Arctic temperature change far exceed estimated early Holocene values in most locations, portending the eventual loss of most of the Arctic’s small glaciers. Read more
Strong increase in thawing of subsea permafrost in the 22nd century caused by anthropogenic climate change The Cryosphere DOI 10.5194/tc-16-1057-2022 17 June 2022 Thawing permafrost releases carbon to the atmosphere, enhancing global warming. Part of the permafrost soils have been flooded by rising sea levels since the last ice age, becoming subsea permafrost (SSPF). The SSPF is less studied than the part on land. In this study we use a global model to obtain rates of thawing of SSPF under different future climate scenarios until the year 3000. After the year 2100 the scenarios strongly diverge, closely connected to the eventual disappearance of sea ice. Read more
Towards hybrid modeling of the global hydrological cycle Hydrology and Earth System Sciences DOI 10.5194/hess-26-1579-2022 15 June 2022 We present a physics-aware machine learning model of the global hydrological cycle. As the model uses neural networks under the hood, the simulations of the water cycle are learned from data, and yet they are informed and constrained by physical knowledge. The simulated patterns lie within the range of existing hydrological models and are plausible. The hybrid modeling approach has the potential to tackle key environmental questions from a novel perspective. Read more
Evaporation enhancement drives the European water-budget deficit during multi-year droughts Hydrology and Earth System Sciences DOI 10.5194/hess-26-1527-2022 13 June 2022 Droughts are a creeping disaster, meaning that their onset, duration and recovery are challenging to monitor and forecast. Here, we provide further evidence of an additional challenge of droughts, i.e. the fact that the deficit in water supply during droughts is generally much more than expected based on the observed decline in precipitation. At a European scale we explain this with enhanced evapotranspiration, sustained by higher atmospheric demand for moisture during such dry periods. Read more
Performance of temperature and productivity proxies based on long-chain alkane-1, mid-chain diols at test: a 5-year sediment trap record from the Mauritanian upwelling Biogeosciences DOI 10.5194/bg-19-1587-2022 10 June 2022 A 5-year record of long-chain mid-chain diol export flux and composition is presented with a 1- to 3-week resolution sediment trap CBeu (in the NW African upwelling). All environmental parameters as well as the diol composition are dominated by the seasonal cycle, albeit with different phase relations for temperature and upwelling. Most diol-based proxies are dominated by upwelling. The long-chain diol index reflects temperatures of the oligotrophic summer sea surface. Read more