bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of a weakened Atlantic Meridional Overturning Circulation in modulating temperature and precipitation extremes over Europe
Authors: Ma Qiyun , Shi Xiaoxu , Sidorenko Dmitry , Scholz Patrick , Lohmann Gerrit , Ionita Monica
Published: February 2023

The Atlantic meridional overturning circulation (AMOC) plays an important role in regulating global and regional climates, especially the European climate, as it affects northward heat transport. Climate model simulations project a decline in the strength of AMOC under future climate change, although high uncertainties exist across models. The potential slowdown of AMOC could cause large and rapid changes in the climate and is therefore regarded as a ‘low probability-high impact’ event. However, how a weakening AMOC affects temperature and precipitation extremes remains poorly understood. Here we use a state-of-the-art global climate model, a new version of the Alfred Wegener Institute Climate Model (AWI-CM3), to quantify these impacts on Europe. We have performed freshwater hosing experiments to weaken the strength of AMOC and to investigate its sensitivity to different freshwater forcing regions. Our results reveal that the largest decline in AMOC generally appears when additional freshwater is put directly at regions of deepwater formation, especially around the Irminger Sea. As atmospheric responses, widespread cooling and less precipitation are found in the Northern Hemisphere mid-latitudes. We further identify the changes in precipitation and temperature extremes on different timescales. Droughts and cold days are very pronounced under AMOC attenuations, and we argue that they may have a stronger impact than the system's mean responses. Our results provide implications for understanding European weather and climate response to a weakening of AMOC in the past, present, and future.
Integrated geophysical-petrological inversion of surface wave and other data for the lithological structure of the Iberian crust
Authors: Clemente-Gómez Carlos , Fullea Javier , Arnaiz-Rodríguez Mariano S.
Published: February 2023

The Earth’s crust hosts most of the geo-resources of societal interests (e.g. minerals, geothermal energy etc.). Integrative approaches combining geophysical and petrological observations to study the mantle assuming thermodynamic equilibrium are relatively common nowadays. However, in contrast to the mantle, where thermodynamic equilibrium is prevalent, vast portions of the crust are thermodynamically metastable. This is because equilibration processes are essentially temperature activated and the temperature in the crust is usually too low to trigger them. Consequently, the mineralogical assemblage of crustal rocks is mostly decoupled from the in situ pressure and temperature conditions, reflecting instead the conditions present at the moment of rock formation. Here we present a new methodology for integrated geophysical-lithological multi-data modelling of the crust. Our primary constraining data are fundamental mode Rayleigh wave surface wave dispersion curves determined by interstation cross-correlation measurements and teleseisms, as well as surface elevation (isostasy) and heat flow. Additional prior information is provided by P-wave velocities coming from controlled source and body wave tomography data. The inversion is framed within an integrated geophysical-petrological setting where mantle seismic velocities and densities are computed thermodynamically as a function of the in situ temperature and compositional conditions. In the crust we invert for a three-layered crust defined by Vs, density and Vp/Vs ratios (or Poisson coefficients) linked according to statistical correlations from global petrophysical data sets. The new methodology is applied to the Iberian Peninsula and adjacent margins where we jointly invert for both the crustal and lithospheric mantle structure. Our results show that the Iberian upper-middle crust is characterized by a clear dichotomy between the high Vs and felsic lithologies (Vp/Vs<1.76) in the Iberian Massif, and the low Vs and mafic lithologies (Vp/Vs>1.81) in the Betic, Pyrenees and Cantabrian Alpine mountain chains. The pattern changes in the lower crust where we obtain felsic lithologies  in  the Central system, NE Betics and N Mediterranean margin, and mafic lithologies in the Ossa-Morena, South-Portuguese, Galician, and Asturian-Leones terranes in the Variscan Iberian Massif. Overall we find a good correlation with previous geophysical studies (receiver functions, controlled source seismics) and the petrology of the main magmatic episodes since the Neoproterozoic (575 Ma).
Magma ocean crystallization model coupling fluid mechanics and thermo-chemistry: application to the lunar magma ocean.
Authors: Rey Laurine , Keller Tobias , Wong Ying-Qi , Tackley Paul , Liebske Christian , Schmidt Max
Published: February 2023

Understanding the dynamics of magma ocean crystallisation during planetary cooling can elucidate the initial mantle structure and subsequent evolution of early planetary bodies. However, most studies on magma ocean crystallisation focus on either the thermo-chemistry (e.g., Johnson et al. 2021) or the fluid dynamics of a cooling magma ocean (e.g., Maurice et al. 2017). This precludes investigations into coupled thermo-mechanical processes, such as the effect of convection and phase segregation on chemical differentiation. However, coupled models are challenging to implement due to their numerical complexity and limited experimental constraints on magma ocean crystallisation for model calibration.We develop a two-phase, 6-component model in a 2D rectangular domain based on a multi-phase, multi-component reactive transport model framework (Keller & Suckale, 2019). Magma ocean convection is modelled using Stokes equations while crystal settling is calculated using a form of hindered Stokes law. The fluid mechanics model is coupled with a thermo-chemical model of evolving temperature, phase proportions, and phase compositions to form a reactive transport model, following Keller & Katz (2016). We apply this model to the lunar magma ocean (LMO) by describing the melt and crystal compositions with 6 pseudo-components (approximating forsterite-fayalite, orthopyroxene-clinopyroxene and anorthite-albite mineral systems). To calibrate the melting temperature and composition of each component, we fit data from fractional crystallisation experiments for a Taylor Whole Moon composition (Schmidt & Krättli 2022) using a transitional Markov Chain Monte Carlo method.The 6-component melting model calibrated to experimental data is successfully implemented in the reactive transport model. First results indicate the importance of crystal settling speed and magma convection speed on convective mixing, magma ocean stratification, and crystal cumulate formation. The small size of the Moon and its relatively well-constrained magma ocean history, make the LMO an excellent case study to apply the model. However, with the aid of new experimental data for larger and chemically different planets, such as Mars, this model can provide more general insight into the early evolution of terrestrial bodies.REFERENCES: Maurice et al. (2017) doi:10.1002/2016JE005250, Johnson et al. (2021) doi: 10.1016/j.epsl.2020.116721,  Keller & Suckale (2019) doi:10.1093/gji/ggz287, Keller & Katz (2016)  doi: 10.1093/petrology/egw030,  Schmidt & Krättli (2022) doi:10.1029/2022JE007187
Greenhouse gas emissions and global warming potentials of five paludiculture plants in fen peatlands in southern Germany
Authors: Bockermann Carla , Eickenscheidt Tim , Drösler Matthias
Published: February 2023

The concept of paludicultures is growing in importance as a promising climate mitigation measure and a sustainable alternative to current agricultural use of organic soils. Besides agricultural and economic viability, quantifying the climatic effects of paludicultures is essential to give reliable policy advice and facilitate sustainable management decisions with regard to climate change. Emission factors (EFs) of the relevant greenhouse gases (GHG) carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) for a variety of potential paludiculture plants are still rare, especially from comparable treatments and site conditions.Five different temperate fen plant species (Carex acutiformis, Phragmites australis, Phalaris arundinacea, Typha latifolia and T. angustifolia) were established as paludicultures with one or two-cut harvest frequencies at three former grassland or arable sites on fen peatland in southern Germany. Ground water levels (gwl) were manipulated to generate a water table gradient spanning annual mean gwl between +4 to −22 cm to derive an optimum gwl for GHG mitigation. One to five years after plant establishment, we measured fluxes of CO2, CH4 and N2O to obtain annual budgets (n=81 / 43 rewetted: gwl +4 to −10 cm, 38 moderately rewetted: gwl −11 to −22 cm) using manual and automatic closed chambers. Besides gas flux measurements, we observed vegetation growth parameters (LAI, NDVI) and biomass yield from harvests. The resulting mean global warming potentials are −13.0 ± 13.9 t CO2-eq ha−1 yr−1 under rewetted conditions (annual mean gwl ≥ −10 cm) and −1.0 ± 9.8 t CO2-eq ha−1 yr−1 under moderately rewetted conditions (annual mean gwl < −10 cm). Our dataset revealed that a maximum mitigation potential of paludicultures is achieved at a gwl of −7 cm. These values represent the first EFs of paludicultures for potential integration into the German national GHG inventory.
Risk-based Assessment of Salt Domes as Disposal Sites for Nuclear Waste: Uncertainty of Groundwater Age in the Salt Dome Problem
Authors: Suilmann Jonas , Perin Andrea , Broggi Matteo , Graf Thomas , Molson John W.
Published: February 2023

Long-term safety has to be assured for the disposal of high-level nuclear waste to prevent contamination of the biosphere. A numerical framework for the probabilistic assessment of hazardous events regarding nuclear waste disposal in salt domes is developed here. The goal is to numerically simulate transport times and mass fluxes of radionuclides into the biosphere, and to couple this with a probabilistic framework for reliability assessment. This model can deal with uncertainties such as the impact of external events (major climate changes, human activities, earthquakes) on subsurface structure, material properties and boundary conditions. To quantify the impact of external events, a numerical model of the far field of a salt dome disposal site is generated. It includes the simulation of density-driven (thermohaline) flow, heat transport, transport of dissolved salt and a radionuclide in discretely-fractured porous media using the FE-code HEATFLOW-SMOKER Version V3/TC2.As a first step in quantifying the effects of uncertain parameters in the context of nuclear waste disposal in salt domes, the salt dome problem (HYDROCOIN level 1 case 5) is further investigated in terms of groundwater age. Groundwater age is one of the exclusion criteria in the site selection process for nuclear waste deposits and therefore of great importance. Groundwater age is here calculated as a transport problem using steady-state flow velocities. This problem is density-driven due to transport of salt into the model domain and the steady-state solution is highly dependent on dispersion.  A sensitivity analysis is carried out to quantify the effect of uncertain dispersion on flow and salt distribution and resulting groundwater age. Preliminary simulation results demonstrate that both salt distribution and groundwater age in steady-state are significantly affected by longitudinal and transversal dispersivity. Resulting flow velocities are higher with increased dispersion and therefore lead to a decreased maximum groundwater age in the model domain.
Progress on FCDR of MWRI onboard FY-3 Series Satellites
Authors: Wu Shengli , Sun Ling , Sun Fenglin , Gu Songyan , Zhang Peng
Published: February 2023

A long time series fundamental climate data record (FCDR) have been developed using operational L0 data from Microwave Radiation Imager (MWRI) onboard FengYun-3 series satellites. This FCDR contains re-calibrated brightness temperature data from three MWRIs mounted on FY-3B/3C/3D satellites from 2010 to 2021. Corresponding to the very unique on-orbit calibration system design of MWRI, the calibration error of the sensors may come from the hot-load reflector back-lobe, hot-load reflector emissivity, hot-load efficiency, cold reflector RFI, and receiver non-linearity. Therefore, a comprehensive error analysis is performed by using the double-difference (DD) method. GPM Microwave Imager (GMI) data are also used as a reference sensor. Simultaneous Conical Overpassing (SCO) method is selected to sample the paired data from two satellites. Based on temporal and spatial SCO rules, the required DD thresholds over a stable ocean surface or rain forest is determined and the optimized re-calibration parameters are derived from the multiple iterations. After reprocessing, the obvious improvement for all channels from 10GHz to 89GHz is shown in the root mean squared error (RMSE) of MWRI with respect to GMI which is significantly reduced from 5K to 1K. The RMSE of all 3 instruments and all channels is decreased to less than 1.5K. Most of the channels' RMSE is around 1K or even less. The bias time series between MWRI and GMI also shows very stable from 10GHz/18GHz.Recently, some typical climate parameters retrieval using FCDR of MWRI have been done by different researchers, including sea ice concerntration, soil moisture, soil frozen and thaw detection, land surface microwave emissivity. The results are very encourage compared with operational MWRI datasets.
The impact of drop size distribution variability and rainfall attenuation on autonomous vehicle sensors
Authors: Husnoo Nawal , Jones Dave
Published: February 2023

The safety of autonomous vehicles will depend critically on the performance of sensors (such as 77GHz radar), which will degrade in the presence of propagation losses during severe weather events. Variations in the drop size distribution lead to significant uncertainty in attenuation estimates. As part of the UK government's commitment to the safe introduction of autonomous vehicles, and in collaboration with the National Physical Laboratory, we have set up a series of observing platforms at Met Office Cardington to measure a multitude of weather-related variables such as temperature, pressure, illumination, precipitation particles, fog, etc. In this contribution, I will cover our work on characterising the rain drop size distribution, using a network of 5 disdrometers located 125m apart, and returning a drop size distribution every minute. From the spectra, we derived an estimate of the attenuation, including an estimate of the uncertainty.
Ice shelf buttressing – a comparison of Antarctic ice shelves in a transient evolution
Authors: Schöll Simon , Reese Ronja , Winkelmann Ricarda
Published: February 2023

The accelerating loss of grounded ice in Antarctica at present is mainly caused by a thinning of the surrounding ice shelves and a subsequent reduction in buttressing. The adjacent ice streams speed-up due to the decrease in back-pressure from the weakened ice shelves. Most methods typically used to quantify the buttressing of ice shelves analyze the state at individual locations along the grounding line or within the shelf. Based on the stress-balance at the grounding line, we here present a method to quantify shelf-wide buttressing values in Antarctica. The Parallel Ice Sheet Model (PISM) and Úa are used in diagnostic as well as in transient experiments to compare the buttressing effect of major ice shelves in Antarctica. We show an increase in buttressing in more confined ice shelves and a decrease for higher basal melt rates. The buttressing decreases consistently across different ice shelves and idealized ocean warming scenarios. The newly-developed, shelf-wide buttressing metrics can be used to understand the role of ice shelves in changing climate conditions.
Estimating worst-case European windstroms, and worst-case seasons, using seasonal forecasts.
Authors: Maddison Jacob , Catto Jennifer , Siegert Stefan , Hansen Sandra
Published: February 2023

Windstorms pose continual risk to Europe. Among their associated hazards, strong near-surface winds can be particularly damaging, threatening infrastructure, life and billions of pounds in insured losses. Insurers (and reinsurers) therefore need to prepare for the potential cost of extreme windstorms. Storm severity indices (SSIs) have been developed to quantify the potential losses associated with windstorm winds. Here, the most extreme windstorms that could potentially occur in the current climate are estimated using seasonal forecast data together with a cyclone-tracking algorithm, and their potential losses quantified using an SSI. As maximum wind gusts, the typical input variable for SSIs, are not available in the seasonal forecast dataset, a method is developed to calculate SSIs using wind speed data and a bias correction used to convert to SSI values representative of those obtained when calculated using wind gusts. Nearly 700 extended winter seasons of forecast data are analysed, representing a much larger sample of potential windstorms compared to that available from reanalysis or observational products. The storm track is reasonably well represented in the seasonal forecast data: spatial features are similar to those in a reanalysis, but there exists a slight poleward bias and underestimation of number of storms per season (maximal underestimation of around 10%). Additionally, distributions of SSI values for several countries in Europe are similar in the forecast data and reanalysis. Together, these suggest that the seasonal forecast data is suitable for analysing windstorm statistics and informing on potential extreme storms. We give estimates of worst-case storms, and worst-case seasons, that are identified in the forecast data and compare to those seen in a reanalysis, highlighting the potential insurance loss implications.
Intraplate Lithospheric Deformation Forms Large Volcanic Regions
Authors: Ranero César R. , Gomez de la Peña Laura , Prada Manel , Jimenez Estela , Cadenas Patricia , Neri Alejandra , Merino Irene , Ugalde Arantza , Grevemeyer Ingo
Published: February 2023

Large igneous systems form either in areas of thin lithosphere at or near plate boundaries or by mantle-melting anomalies in intraplate settings with comparatively thicker lithosphere. Decompression melting or flux melt dominate at plate boundaries. Intraplate magmatism relates to thermal or compositional anomaly in the mantle. Although questions remain open, our understanding of the fundamental driving processes of these systems has dramatically improved during the last 50 years. However, some intraplate large volcanic regions display a complex distribution of magmatic activity that spans a large age range and does not appear easily explained by semi-stable mantle-melting anomalies. The Madeira-Tore Rise (MTR) is often associated to excess magmatism forming thick oceanic crust at Cretaceous time. However, the ~1000 km long MTR broad bathymetric swell contains numerous individual volcanic constructions of different dimensions and age, across a hundreds-of-km wide swath. The MTR and volcanic constructions origin is unclear. The MTR magmatic event is inferred to be associated to the seafloor-spreading magnetic lineation named the J-anomaly, and the MTR is often referred as J-anomaly ridge. However, when analysed in detail, the magnetic J-anomaly is located east of the rise. Many volcanoes are inferred hot-spot related.Seismic data collected in 2018 & 2022 show that the basement ridge of the MTR swell is unrelated to thick crust but to long-wavelength lithospheric flexure. The lithospehre deformation is expressed by folding, faultiong and large-scale tilting indicated by regional angular stratigraphical uncorformities. The spatial and temporal coincident of deformation with the MTR volcanic region support that long-lived volcanism may be related to lithospheric-scale intraplate deformation unrelated to hot spot activity.
River-coastal-ocean continuum modelling and assessment of nearshore dynamics
Authors: Causio Salvatore , Bonamano Simone , Federico Ivan , Piermattei Viviana , Piazzolla Daniele , Scanu Sergio , Madonia Alice , De Cillis Giovanni , Jansen Eric , Coppini Giovanni , Marcelli Marco
Published: February 2023

Complex processes involved in the river delta areas are not fully solved with a traditional structured-mesh model. A seamless unstructured-grid approach could serve as support to advance in the reproduction and understanding of the dynamics processes across different scales. In this work, a river-coastal-ocean continuum modeling representation has been developed for the Tiber River delta, including the surrounding coastaland open-ocean zones of the Lazio coast (Tyrrhenian Sea, Italy). This area has been selected because it includes important naturalistic sites but also a new commercial, fishery and leisure harbor whose the realization is scheduled for 2023. By using temperature and salinity profiles from near-river CTD data, we demonstrate that this representation simulates the coastal dynamic processes in the Tiber delta zone better than the classic coastal-ocean representation, minimizing calibration and sensitivity experiments. In this work, a large effort has been dedicated to the acquisition of new observations (CTD, drifters, currents radar, bathymetric survey) carried out over different spatial (open-ocean, coastal and near- and along-river) and temporal scales. Validation demonstrated that the model has good accuracy, also in reproducing the salt wedge intrusion along river. Furthermore, currents investigation suggested the existence of an anticyclonic gyre in proximity of the river mouth of the northern branch, mainly induced by river discharge and coastal morphology. These promising results in simulating cross-scale processes in a seamless fashion, will be included in the near future in an operational system for coastal forecasting.
Monitoring and prediction of InSAR-derived post-seismic hillslope deformation rates
Authors: Tanyas Hakan , He Kun , Sadhasivam Nitheshnirmal , Lombardo Luigi , Chang Ling , Fang Zhice , Dahal Ashok , Fadel Islam , Hu Xiewen , Luo Gang
Published: February 2023

Strong earthquakes not only induce co-seismic mass wasting but also exacerbates the shear strength of hillslope materials and cause higher landslide susceptibility in the subsequent years following the earthquake. Previous studies have mainly investigated post-seismic landslide activity mainly by using landslide inventories. However, landslide inventories do not provide information on deformation given by ground shaking and limit our observations to only failed hillslopes. As a consequence, we lack comprehensive, quantitative analysis revealing how hillslopes behave in post- seismic periods. Satellite-based synthetic aperture radar interferometry (InSAR) could fill this gap and provide millimeter-scale measurements of ground surface displacements that can be used to monitor hillslope deformation.InSAR also provides a rich dataset to put shed light on spatiotemporal patterns of hillslope deformation, which are influenced by a combination of static and dynamic environmental characteristics specific to any landscape of interest. However, these influences are yet to be explored and exploited to train data-driven models and make predictions on the deformation one may expect in space or time.Here we use the Persistent Scatterer Interferometry technique to monitor pre- and post- seismic hillslope deformations for the area affected by the 2017 Mw 6.9 Nyingchi, China earthquake that occurred on the 2017 18th of November 2017 earthquake. We use Sentinel-1 satellite data acquired between 2016 and 2022 to examine post-seismic hillslope evolution. Using the same dataset, we also explore developing an interpretable multivariate model dedicated to InSAR-derived hillslope deformationsOur results show that the average post-seismic hillslope deformation level in the study area is still higher than its pre-seismic counterpart approximately four and a half years after the earthquake. As for the multivariate model dedicated to InSAR-derived deformation data, the results we obtain are promising for we suitably retrieved the signal of environmental predictors, from which we then estimated the mean line of sight velocities for a number of hillslopes affected by seismic shaking.
Simulating the effects of Ice-nucleating particles in Antarctica in COSMO-CLM²
Authors: Sauerland Florian , Souverijns Niels , Possner Anna , Wex Heike , Van Overmeiren Preben , Mangold Alexander , Van Weverberg Kwinten , van Lipzig Nicole
Published: February 2023

The remoteness of the Antarctic continent has important implications for the microphysical properties of clouds: In particular, the rare abundance of ice-nucleating particles (INP) limits the primary nucleation of ice crystals. Yet, persistent mixed-phase clouds with ice crystal number concentrations of 0.1-1l-1 are still observed in the Arctic and Antarctic. However, the ability of regional climate models to reproduce these mixed-phase clouds remains limited, much like the knowledge about their climatological effects. Thus, we added a module to the regional climate model COSMO-CLM² aimed at improving the parametrisation of the aerosol-cycle, which allows us to prescribe different concentrations of INPs. We examined the model response to different concentrations by running it in an area around the Belgian Princess Elisabeth Station in Dronning Maud Land for one month and with four different concentration settings: The first, corresponding to the low end of INP concentrations we observed at the station, the second, corresponding to the high end of INP concentrations we observed at the station, and the third and fourth, to the low and high end of continental observations. The performance was evaluated by comparing the simulation results with radar and ceilometer observations taken at the station. Finally, we analysed the differences between the four simulations to determine the overall sensitivity of the model to variability in INP concentrations, which allows us to draw conclusions about the importance of accurately simulating processes related to ice nucleation, and about the climatological implications that a change in aerosol concentrations would have.
Geopolitical risk induced by terrestrial moisture supply to agricultural hotspots
Authors: Posada-Marín Jose Andrés , Salazar Juan Fernando , Wang-Erlandsson Lan , Rulli Maria Cristina , Jaramillo Fernando
Published: February 2023

Water availability can be linked to a country's stability, internal security, and the occurrence of violence and governability, in the environmental change context. For instance, lack of access to water resources can trigger political conflicts, be used as a tool for political negotiation or attacks on water infrastructure can be used as a source of intimidation. The potential political risks associated with water availability take particular relevance at the scale of international and transboundary hydrological basins and under conditions of water-food scarcity or political instability. To date, although water risks occurring within the boundaries of the hydrological basin have been studied across several case studies in the literature, the issue of risks arising from water upwind-downwind dependency has been overlooked. For instance, precipitation in a hydrological basin or agricultural centre regions with a high dependency on terrestrial moisture recycling may originate in upwind terrestrial areas outside of the basin boundaries. Here we study geopolitical risk related to this water dependency by analizing terrestrial moisture recycling. Our analysis shows that some hydrological basins in Africa, Asia and South America present a high risk of experiencing geopolitical conflicts when there is a large extension of croplands, high moisture recycling dependency and their precipitationsheds extend over warmongering countries. Hence, our results indicate that addressing transboundary water security from a surface perspective can underlook potential geopolitical conflicts that may threaten regional water-food security and peace. These risks need special international attention to guarantee global peace and agricultural production.
Laboratory experiments on internal solitary wave reflections and their detectability via water surface infrared thermography
Authors: Vincze Miklos , Kiss Zsolt Áron
Published: February 2023

We report on results from laboratory experiments performed in a quasi-two-layer system of cold and warm water in a rectangular laboratory tank. Warm front propagation is initiated by removing a vertical barrier from between the two prepared sections of the tank containing cold and warm water filled up to the same level. The warm front propagation in the vicinity of the free water surface is monitored using a high precision infrared camera from above, and with dye visualisation from the side simultaneously. After the warm front reaches the sidewall of the tank, its "head" is reflected, and hence an internal bore emerges along the interface separating the two layers. Following further reflections the bore splits to a train of internal solitary waves, resembling the solutions of the KdV equation. We find that, interestingly, although the waves propagate along the internal interface, certain surface signatures of the bore and wave dynamics can be detected from the water surface temperature fields due to secondary convective flows. This result may have certain applicability for the detection of internal waves using infrared sea-surface temperature data from satellites.
A proposal for engaging amateur scientists in climate forecasting
Authors: Stainforth David A.
Published: February 2023

Twenty years ago in 2003 the climateprediction.net project was launched. It gave members of the public the opportunity to engage in climate modelling and climate prediction by downloading a comprehensive climate model and running it on their PCs. Participants contributed their results to a large perturbed-parameter ensemble and thus supported an exploration of uncertainty in climate projections. What the project did not do was give the participants much opportunity for participating in the experimental design or data analysis. Nowadays the questions regarding uncertainty in model-based predictions remain. Unlike twenty years ago, however,  there are many more individuals in our societies who have skills in computing, statistics, physics, geophysics etc. and who have an interest in research but are not part of the research community and don’t want a career in academia. Here I will present a potential project to engage such individuals in exploring and quantifying uncertainty in real-world extrapolatory forecasts of the climate system - that’s to say of climate change. Key to this would be the use of a range of simple, low-dimensional stochastic models founded on the Hasselmann model. Participants would be asked to both code and run ensembles of various versions of the model to explore physical science uncertainties in feedback processes, ocean heat uptake, the scale and type of the stochastic forcing, and even the structure of the model. They would participate in a collection of standardised experiments - common across multiple individuals - to allow for verification of results but they would also be encouraged to run their own experiments and to propose extensions to the main project in collaborative teams. Such a project would provide a route to enable skilled and interested individuals throughout society to participate in climate research and also to contribute to the wider communication and understanding of the climate prediction and uncertainty quantification problems. This proposal is for a citizen science project that takes scientific engagement to a new level - a project that enables those in society who want to contribute as active researchers to do so but on a voluntary basis without the pressures and demands of a typical academic career.
A precautionary approach to carbon dioxide removal needs
Authors: Ganti Gaurav , Lejeune Quentin , Gidden Matthew , Smith Christopher , Nauels Alexander , Schleussner Carl-Friedrich
Published: February 2023

A central finding of the most recent reports of the Intergovernmental Panel on Climate Change (IPCC) is that net zero CO2 emissions are required for stabilizing CO2-induced global average surface temperature increase. However, given substantial uncertainties of the earth system response after reaching net zero CO2, outcomes of long-term declining, or continuously increasing global temperatures after achieving and maintaining net zero CO2 emissions cannot be excluded. At the same time, nearly all emission reduction pathways  assessed by the IPCC, which are consistent with global climate goals, require large-scale deployment of carbon dioxide removal (CDR) to balance remaining positive emissions and to draw down temperatures after a peak. Using evidence from Earth System Models and Simple Climate Models we show that peaking global mean temperature may potentially require net CO2 removals of the order of several hundred gigatonnes (Gt) sustained over multiple decades in case of strong positive earth system feedbacks. We also estimate the contribution of scenario uncertainty (e.g., reduction in emissions of different greenhouse gases) to such net CO2 removal figures. A precautionary approach to ensure a very high chance of peaking of global mean temperature may therefore require the availability of substantial amounts of CDR. Our findings have direct implications for CDR needs in order to achieve the long-term temperature goal of the Paris Agreement. The potential risk of strong earth system feedback outcomes have to be carefully considered when discussing temperature reversal in case of a (temporary) overshoot above the 1.5°C threshold, in particular as there are well-documented biophysical, technological and sustainability limits to CDR deployment.
Collective attribution and future risk assessment of recent high-impact wildfire events
Authors: Liu Zhongwei , Eden Jonathan , Dieppois Bastien , Drobyshev Igor , Conradie Stefaan , Gallo Carolina , Blackett Matthew
Published: February 2023

In recent years, the occurrence of a series devastating wildfire events around the world has raised considerable public concern about how climate change is altering meteorological conditions conducive to such events. The relative scarcity of wildfire attribution studies, coupled with the limited observational record, has added to the difficulty of developing reliable collective conclusions for future forest management strategies. Recent work has discussed the uncertainties and sensitivities associated with the choice of meteorological indicator to represent fire weather and the validation of climate model ensemble in the context of extreme event attribution, but the value of linking the attribution of recent record-breaking wildfire events with future risk assessment has not yet been fully explored.Here, using an established probabilistic framework based on extreme value theory, we present the findings of attribution analysis applied to a series of recent high-impact wildfire. In each case, fire weather extremes, represented by annual maxima of the Canadian Fire Weather Index (FWI), are fitted to an extreme value distribution and scaled to the global mean surface temperature. Probability ratios are used to quantify the influence of rising global temperatures on the changing frequency of FWI extremes for past, present and future climates. We demonstrate the value of the application of a common methodological framework in combining results from different case studies as part of a collective attribution approach for multiple extreme across several world’s fire-prone regions. Further analysis of future risks will provide robust recommendations to reduce and address the hazards posed by wildfires and to improve post-disaster resilience.
Deep learning-based tropical cyclone intensity prediction through synergistic fusion of geostationary satellite and numerical prediction model
Authors: Lee Juhyun , Im Jungho
Published: February 2023

The accurate forecasting of the intensity of tropical cyclones (TCs) is able to effectively reduce the overall costs of disaster management. In this study, we proposed a deep learning-based model for TC forecasting with the lead time of 24, 48, and72 hours following the event, based on the fusion of geostationary satellite images and numerical forecast model output. A total of 268 TCs which developed in the Northwest Pacific from 2011 to 2019 were used in this study. The Communications system, the Ocean and Meteorological Satellite (COMS) Meteorological Imager (MI) data were used to extract the images of TCs, and the Climate Forecast System version 2 (CFSv2) provided by the National Center of Environmental Prediction (NCEP) was employed to extract atmosphere and ocean forecasting data. In this study, we suggested hybrid convolutional neural network (hybrid-CNN)-based TC forecasting models. It enables to efficiently consider not only the physical but also the spatial characteristics of variables. The Joint Typhoon Warning Center (JTWC) was used for validating the suggested model, and Korea Meteorological Administrator (KMA)-based operational TC predictions were utilized for evaluating the performance of the model. A hybrid-CNN-based prediction model obtained mean absolute errors (MAE) of 13.58, 16.48, and 21.64 kts and skill scores (SS) of 29%, 19%, and 1.6% for 24h, 48h, and 72h forecasts, respectively. Since the rapid intensification (RI) is one of the challenging tasks in the TC intensity prediction, the performance of suggested model for all RIs in 2019 were additionally evaluated. Compared to KMA-based predictions, the suggested models achieved average SS of 66%. Furthermore, using an explainable artificial intelligence (XAI) approach, it is possible to verify how the suggested model works for forecasting TC intensity and propose the feasibility of the suggested model in the meteorology field. 
Modelling of DAS cable and ground coupling response using Discrete Particle Schemes
Authors: Celli Nicolas Luca , Bean Christopher J. , O'Brien Gareth , Nooshiri Nima
Published: February 2023

Since its first applications in the past decade, the use of fiber optic cables as ground motion sensors has become a central topic for seismologists, with successful applications of Distributed Acoustic Sensing (DAS) in various key fields such as seismic monitoring, structural imaging and source characterisation.The instrument response of DAS cables however is largely unknown. Instrument response is a combination of instrument design, local site effects and ground coupling, and for DAS, the latter ones are believed to have a strong, spatially variable, but yet largely unquantified effect. This limits the application of a large number of staple seismological techniques (e.g. earthquake magnitude estimation, waveform tomography) that can require accurate knowledge of a signal’s amplitude and frequency content.Here we present a method for accurately simulating a DAS cable and its response. The scheme is based on molecular dynamic-like particle-based numerical modelling, allowing the investigation of the effect of varying DAS-ground coupling scenarios. At first, we compute the full strain field directly, for each pair of neighbouring particles in the model. We then define a virtual DAS cable, embedded within the model and formed by a single string of interconnected particles. This allows us to control all aspects of the cable-ground coupling and their properties at an effective granular level through changing the bond strengths and bond types (e.g. nonlinearity) for both the cable and the surrounding medium. Arbitrary cable geometries and heterogeneous materials can be accommodated at the desired scale of investigation.We observe that at the meter scale, realistic DAS materials, cable-ground coupling and the presence of unconsolidated trench materials around it dramatically affect wave propagation, each change affecting the synthetic DAS record, with differences exceeding at times the magnitude of the recorded signal. These differences show that cable coupling and local site effects have to be considered both when designing a DAS deployment and analysing its data when either true or along-cable relative amplitudes are considered.
A framework for understanding the correlation between aggregated losses of compound events
Authors: Jones Toby , Stephenson David , Priestley Matthew
Published: February 2023

The risk from individual natural hazards (such as extratropical cyclones) can be large, but the aggregate loss over yearly timescales is significantly greater. For example, wind damage from the three major European windstorms in February 2022 caused more than €3.5 billion of insured losses.This study proposes a random sum modelling framework for understanding the correlation between aggregate risks that occur from compound events. By considering the frequency and intensities of compound events as random variables, the framework provides an expression for correlation between two random sums (which each represent different types of loss from compound events).The framework shows that this correlation will generally increase monotonically towards one as the dispersion (clustering) of the number of events increases. Under certain conditions, the correlation will always monotonically increase with dispersion.The framework has been illustrated by applying it to annual sums from 1980-2020 using wind speed and precipitation as proxy measures for insured loss. This is calculated from ERA5 reanalysis data which includes 39587 storm events and covers the European region and Atlantic Ocean (from 30°N 100°W to 75°N 40°E).The framework performs well, capturing the general behaviour of the correlation, with large positive correlation over the N. Atlantic Ocean and weaker correlations over European land regions.
Regional impacts of climate stabilisation across multiple global warming levels
Authors: Dittus Andrea , Hawkins Ed
Published: February 2023

The 2015 Paris Agreement adopted by 192 parties states the goal of limiting global warming to well below 2, preferably 1.5 degrees Celsius above pre-industrial levels. These goals imply an ambition to stay at or below these levels long-term. Evidence is beginning to emerge that regional patterns of change at given global warming levels (GWLs) can be very different between transiently warming through given GWLs and stabilising at those same GWLs.In this presentation, we explore regional climate change across multiple variables, with a particular focus on regional precipitation change. Using a novel ensemble of six 500-years long fixed concentration simulations across various levels of warming between 1.5 and 5 degrees above pre-industrial with the CMIP6-generation Earth System Model UKESM1.0, we show that precipitation trends opposite in sign to transient climate change projections occur in several regions at the same GWLs. Such differences have important implications for climate change risk assessments and adaptation discussions, which typically only include transient projections. Here, we provide examples where a transient and stabilised climate differ and discuss the possible mechanisms driving these differences. 
Weakly nonlinear wave energy flux and radiation stress
Authors: Pezzutto Paolo
Published: February 2023

It is known that the wave action propagated in spectral wave models is a small steepness approximation of the observable wave action. For relevant steepness, we need higher order corrections to get a proper representation of the sea states [Janssen, 2009]. For the same reasons, other diagnostic variables should be corrected. Based on the fifth order Stokes solution obtained by Fenton [1985], Jonsson and Arneborg [1995] showed the importance of higher order corrections for determining the energy properties of long crested waves.Proceeding from Longuet-Higgins and Stewart [1960], assuming a mean stream velocity, we see that how, using Krasitskii [1994] canonical transformations, we can derive general 2D weakly non linear corrections to the rate of transfer of energy across a surface fixed in space. For a monochromatic wave, the resulting equations are compared with truncated expressions given by Jonsson and Arneborg [1995], confirming that second order contributions (in terms of wave energy) can be relevant, depending on steepness and relative water depth.After applying a proper statistical closure, the derived equations can be used to correct the wave energy properties of wave models spectra, for example to refine the informations transferred to a coupled circulation model.John D. Fenton. A Fifth-Order Stokes Theory for Steady Waves. Journal of Waterway, Port, Coastal, and Ocean Engineering, 111(2):216–234, 1985. ISSN 0733-950X.Peter a. E. M. Janssen. On some consequences of the canonical transformation in the Hamiltonian theory of water waves. J. Fluid Mech., 637(November):1–44, 2009. ISSN 1469-7645.Ivar G. Jonsson and Lars Arneborg. Energy properties and shoaling of higher-order stokes waves on a current. Ocean Engineering, 22(8):819–857, 1995. ISSN 00298018.Vladimir P. Krasitskii. On reduced equations in the Hamiltonian theory of weakly nonlinear surface waves. J. Fluid Mech., 272(-1):1–20, 1994. ISSN 0022-1120.M. S. Longuet-Higgins and R W Stewart. Changes in the form of short gravity waves on long waves and tidal currents. Journal of Fluid Mechanics, 8(04): 565–583, 1960. 
Developing and testing a validation procedure to successfully use on-the-move sensors in urban environments
Authors: Barbano Francesco , Brattich Erika , Cintolesi Carlo , Iurato Juri , Mazzarella Vincenzo , Milelli Massimo , Nizamani Abdul Ghafoor , Sarfraz Maryam , Parodi Antonio , Di Sabatino Silvana
Published: February 2023

With the increasing attempt to empower citizens and civil society in promoting virtuous behaviours and relevant climate actions, novel user-friendly and low-cost tools and sensors are nowadays being developed and distributed on the market. Most of these sensors are typically easy to install with a ready-to-use system, while measured data are automatically uploaded on a mobile application or a web dashboard which also guarantees secure and open access to measurements gathered by other users. However, the quality of the datum and the calibration of these sensors are often ensured against research-grade instrumentations only in the laboratory and rarely in real-world measurement. The discrepancies arising between these low-cost sensors and research-grade instrumentations are such that the first might be impossible to use if a validation (and re-calibration if needed) under environmental conditions is not performed. Here we propose a validation procedure applied to the MeteoTracker, a recently developed portable sensor to monitor atmospheric quantities on the move. The ultimate scope is to develop and implement a general procedure to test and validate the quality of the MeteoTracker data to compile user guidelines tailored for on-the-move sensors. The result will evaluate the feasibility of MeteoTracker (and potentially other on-the-move sensors) to integrate the existing monitoring networks on the territory, improve the atmospheric data local coverage and support the informed decision by the authorities. The procedure will include multi-sensor testing of all the sensor functionalities, validation of all data simultaneously acquired by several sensors under similar conditions, methods and applications of comparisons with research-grade instruments. The first usage of the MeteoTracker will be also presented for different geographical contexts where the sensors will be used for citizen science activities and develop a monitoring network of selected Essential Variables within the HORIZON-EU project I-CHANGE (Individual Change of HAbits Needed for Green European transition).