bluuebunny/crossref_metadata_2025 huggingface dataset:
Bayesian Inference of Climate Parameters Using Multibox EBMs
Authors: Schillinger Maybritt , Ellerhoff Beatrice , Rehfeld Kira , Scheichl Robert
Published: March 2022

Reliable climate projections in face of global warming require a firm and detailed understanding of climate variability. Variations in climate can be externally-forced, for example by anthropogenic emissions, or internally-generated, for example from chaotic atmosphere and ocean dynamics. To investigate the climatic response to radiative forcing, a common concept is the equilibrium climate sensitivity (ECS). Many studies estimate the ECS by fitting simple energy balance models (EBMs) to observational data. This approach has benefitted from advances in numerical analysis and statistics, enabling a fully Bayesian analysis. Via Bayes theorem, it quantifies the probability of certain climate parameters given observations, for example of surface temperature. To this end, it combines the goodness of the model fit with assumptions on measurement errors and climate variability as well as prior information. Here, we analyse and discuss Bayesian inference of climate parameters such as ECS from global mean temperatures using multibox EBMs. We therefore present an R package which relies on the Markov Chain Monte Carlo algorithm and includes an extension of the one-box model with a time-dependent feedback parameter. Using measurements from the instrumental period as well as temperature reconstructions and model data from the last millennium, we validate and demonstrate the package. We find that the two-box model performs significantly better in fitting the observations than the one-box model, and generates 21st century projections that agree more closely with AR5 estimates. Further, we evaluate the robustness of the estimate against uncertainties in temperature and forcing data through synthetic experiments. To this end, we quantify how estimation errors depend on the strength of noise in temperature data and compare the influence of dating and amplitude uncertainties in forcing reconstructions. In summary, we provide an effective tool for Bayesian estimation of climate parameters and elaborate its potential for studying the response to external forcing.  
Recalculating the local magnitude of events in the Hungarian National Seismological Bulletin
Authors: Csatlós Marietta , Süle Bálint
Published: March 2022

Local magnitude is one of the oldest and widely used term for characterizing the size of seismic events. Mostly based on the maximum amplitude measured on the components of the seismograms associated with the seismic event. The events in the Hungarian National Seismological Bulletin were relocated by Bondar et al. (2018). Before 2015 the bulletin did not contain amplitudes therefore it was not possible to calculate new local magnitudes for the new hypocenters. Moreover, the magnitudes were calculated by different methodology before 2015.

In this study, all three components of all available waveforms were collected for the events occurred between 1996 and 2016, and the local magnitudes were recalculated. Thus, we present a consistent data set for the whole period. Magnitude values based on both horizontal and vertical components are presented.

Amplitudes were measured on all three components, thus it was possible to compare the maximum amplitudes of the horizontal and vertical components recorded at stations in different geological conditions. For stations located on sediment, generally higher amplitude values were obtained on the horizontal components. The horizontal amplitude was 2.5 or 3 times larger for the Great Hungarian Plain stations on thick sediments. The differences between stations on firm bed rock were smaller.

The collected waveforms and amplitude measurements provide the opportunity to perform the calibration of the local magnitude scale to the geological conditions of Hungary.

 

 

Bondár, I., Mónus, P., Czanik, Cs., Kiszely, M., Gráczer, Z., Wéber, Z., the AlpArrayWorking Group. 2018: Relocation of Seismicity in the Pannonian Basin Using a Global 3D Velocity Model. Seismological Research Letters. pp.2284-2293.
Unmanned Aircraft Systems and low-cost gas sensor arrays for monitoring dangerous volcanic contexts (Pisciarelli fumarolic field, Campi Flegrei, southern Italy)
Authors: Fedele Alessandro , Somma Renato , Troise Claudia , Holmberg Karen , De Natale Giuseppe
Published: March 2022

In the past 5 years, hydrothermal activity in the Pisciarelli fumarolic field of the Campi Flegrei caldera (southern Italy) has increased dangerously. This has led local and civil protection authorities to restrict access to volcanological monitoring in the area. We present a sampling system designed for real-time atmospheric measurements of hydrothermal gasses using an unmanned aircraft system (UAS) to investigate the Pisciarelli fumarolic field.  UAS use has become an increasingly essential tool for monitoring areas where access is risky for operators. We also describe a low-cost gas sensor array that is designed and fabricated to be assembled and mounted on a commercial drone. The system is equipped to measure methane (CH4), carbon dioxide (CO2), carbon monoxide (CO), and sulfur dioxide (H2S) and is capable of displaying real-time gas concentration values. Our research explores the capabilities of this system and provides some encouraging results to be implemented in future sampling campaigns for gasses emitted into the atmosphere.
Joint inversion of paleomagnetic and cosmogenic isotope data for modeling the global geomagnetic field
Authors: Panovska Sanja , Korte Monika , Adolphi Florian , Nowaczyk Norbert , Scherler Dirk
Published: March 2022

The Earth's magnetic field varies on a range of spatial and temporal scales. Recent models, spanning the past 100 ka, greatly improved our knowledge of the long-term changes of the geomagnetic field, and geomagnetic excursions - events associated with strong directional deviations and low field intensities. However, these models are limited by the spatial and temporal data distribution, and magnetic and age uncertainties of underlying data. Variations in the production of cosmogenic radionuclides, such as 10Be from ice cores and sediments, provide an independent proxy of paleointensity variations for a range of timescales. This study demonstrates the potential of a joint inversion of paleomagnetic data with cosmogenic nuclide production rates to reconstruct the geomagnetic field evolution over the past 70 ka. Here, we present a global compilation of 10Be records, converted to magnetic field intensity, and compare them to paleomagnetic sediment records. General trends of the virtual axial dipole moment (VADM) stacks derived from the two data sets agree well. Two models have been constructed: GGFSS70-10Be where the converted 10Be records are used similarly to the paleomagnetic records, and GGFSS70-10Be-DIP where the converted 10Be data have been considered to be a function of the dipole only (the first three Gauss coefficients). These models are compared to the previously published GGFSS70 model based on paleomagnetic data only. Geomagnetic excursions are reconstructed in the multi-proxy models: the most pronounced Laschamps event (41 ka) and a few other excursional signatures at the times of the Norwegian-Greenland Sea and Mono Lake/Auckland excursions. Model predictions and global field maps show that the cosmogenic isotope records have regional effects on the reconstructed variations (Greenland, South/Southern Ocean, east-equatorial Pacific), especially those with high resolution (Greenland ice cores). The 10Be records not only provide an independent source of information on the geomagnetic field, thus confirming the reliability of the paleomagnetic records, they also improve the global geomagnetic field reconstructions over long timescales.
Translating blue water footprint caps for a river basin to caps per sub-catchment: trade-offs between upstream-downstream uses and the environment
Authors: Schyns Joep , Albers Luc , Booij Martijn
Published: March 2022

Setting upper limits to water consumption per river basin is crucial for ensuring sustainable water use. A blue water footprint cap is an upper limit to the consumptive use of surface and groundwater. A method to determine monthly blue water footprint caps in a river basin as a whole has been proposed (monthly natural runoff minus environmental flow requirements). However, the question remains how to translate caps for a river basin as a whole to caps for each sub-catchment within the basin. A relevant question, because human interventions in rivers have reduced water scarcity in upstream parts of river basins, but aggravated it in downstream parts. We apply two alternative water allocation scenarios to translate blue water footprint caps for the Yellow River basin to caps per sub-catchment and evaluate their effects on upstream-downstream differences in water scarcity: (i) the population-based scenario takes the relative population size per sub-catchment as the basis for water allocation, which makes sense from the perspective of equity and fair sharing of natural resources; (ii) the demand-based scenario takes the historical water demand as the basis for water allocation, which is an option to consider for river basin managers aiming to reduce environmental flow violations. Both scenarios make use of the fact that blue water can be reserved (not consumed) in an upstream sub-catchment for consumption further downstream. We measure the effects of the scenarios against a base case in which sub-catchments are allowed to consume all available water after considering environmental flow requirements without the consideration of downstream uses: the use-what-is-there principle. We find that blue water scarcity increases from upstream to downstream under the use-what-is-there principle. Both the population- and demand-based scenarios reduce upstream-downstream differences in the degree of blue water scarcity. The demand-based scenario is most effective in this respect. On the other hand, the population-based scenario leads to the smallest upstream-downstream differences in water availability per capita. The results feed into a discussion on how to translate upper-limits to water consumption from the river basin to the sub-catchment level which needs to take place for cap-setting to become a practical instrument in river basin management.
Aerosol absorption in global models from AeroCom Phase III
Authors: Sand Maria , Samset Bjørn , Myhre Gunnar ,   AeroCom modellers
Published: March 2022

Aerosol induced absorption of shortwave radiation can modify the climate through local atmospheric heating, which affects lapse rates, precipitation, and cloud formation. Presently, the total amount of aerosol absorption is poorly constrained, and the main absorbing aerosol species (black carbon (BC), organic aerosols (OA) and mineral dust) are diversely quantified in global climate models. As part of the third phase of the AeroCom model intercomparison initiative (AeroCom Phase III) we here document the distribution and magnitude of aerosol absorption in current global aerosols models and quantify the sources of intermodel spread, highlighting the difficulties of attributing absorption to different species. 15 models have provided total present-day absorption at 550 nm (using year 2010 emissions), 11 of which have provided absorption per absorbing species. Of the summed component AAOD, 60 % (range 36-84%) is estimated to be due to BC, 31 % (12-49%) is due to dust and 11% (0-24%) is due to OA, however the components are not independent in terms of their absorbing efficiency, and in models with internal mixtures of absorbing aerosols, a major challenge is the lack of a common and simple method to attribute absorption to the different absorbing species. We discuss challenges of attributing absorption to different species, we compare burden, refractive indices, and density, and we contrast models with internal mixing to models with external mixing. The difference in spectral dependency between the models is striking.
The real potential of fractured aquifers for CO2 storage
Authors: Proietti Giampaolo , Romano Valentina , Pawar Rajesh , Bigi Sabina
Published: March 2022

The CCS (Carbon Capture & Storage) process involves the capture of CO2 produced by energy production plants, cement factories and refineries, transport to storage sites and injection into deep geological structures with physical and chemical characteristics suitable for long-term confinement. This technology can significantly assess the containment of CO2 emissions into the atmosphere, with an estimated reduction between 12% and 14%. One of the most important phases in which the role of the geoscientist is necessary is the screening of the structures with the suitable geological characteristics for CO2 trapping and the estimation of the injectable mass.

Storage capacity estimates are usually approximate and are based on the average geometric and physical values of the geological formations. Furthermore, not knowing in detail the heterogeneity and complexity of geological structures, many storage efficiency scenarios are presented, which consequently propose very different values. Fractured rocks are one of the largest resources on the earth's surface, and host many of the most important reserves of water, oil and natural gas, and can also be exploited for the storage of gas or carbon dioxide. Determining the dynamic behaviour of fluids within a fractured rock mass is a necessary step in the characterization and definition of a potential site for CO2 injection.

In this work a Discrete Fracture Network (DFN) approach is used to quantify the efficiency of fracture systems to the fluid transport, quantifying the mass of supercritical CO2 injectable in a volume of rock with different fracture intensity in a purely discrete approach, with the utilization of dfnWorks and FEHM software. Using multi-phase reservoir simulations of CO2 injection, we determine the efficiency and storage capacity of fractured rocks. The main result this approach is the introduction of the Efr index which quantifies the efficiency of fracture systems for supercritical CO2 injection. This index allows, starting only from the fracture intensity data and using the equations proposed in the literature for the calculation of the storage capacity, to obtain an immediate and reliable estimate of the volume of the aquifers, which consider the efficiency of fractured aquifers to the fluid flow.
Measuring Amazon rainforest resilience from remotely sensed data
Authors: Nian Da , Blaschke Lana , Zheng Yayun , Boers Niklas
Published: March 2022

The Amazon rainforest has a major contribution to the bio-geochemical functioning of the Earth system and has been projected to be at risk of large-scale, potentially irreversible, dieback to a savanna state. Measuring the resilience of the Amazon rainforest empirically is critical to helping us understand the magnitude and frequency of disturbances that the rainforest can still recover from. Different means to quantify resilience in practice have been proposed. Here we determine the Amazon rainforest resilience based on a space-for-time replacement, and then estimating the average residence time in the forest state. This 'global' notion of resilience is different from local measures based on variance or autocorrelation and thus provides complementary information. We study the dependence of the exit-time-base resilience on total rainfall and, in order to study the evolution of the Amazon rainforest, we also estimate changes in their resilience over the years.
Exploring the use of diatoms as a new environmental proxy in Arctic coastal ice cores - A first case study using the RECAP ice core
Authors: Cook Eliza , Jones Viv , Zhu Jackie
Published: March 2022

We have recorded consistent (but low) numbers and a diverse range of diatom taxa (siliceous algae) over a 400-year period in the RECAP ice core, drilled from the Renland ice cap on the east coast of Greenland. This is an exciting initial step in attempting a diatom-based environmental reconstruction for an Arctic ice core for the first time, since Greenland’s inland ice cores (e.g. NGRIP, GRIP) do not appear to contain diatoms in enough numbers. Our novel study investigated the period 1528 - 1940 AD (encompassing the Little Ice Age (LIA)) and we developed a method for extracting diatom taxa from the ice-core meltwater samples for identification. This was done by microscopy using standard taxonomic techniques. In summary, the RECAP LIA assemblage comprises 93 species, 36 genera and 11 families where Thalassiosira/Coscinodiscus, Aulocoseira, Pinnularia, Nitzschia, Luticola, Diadesmis, Staurosira, Achnanthidium, Psammothidium spp are the dominant genera. In this interval we found that Renland received air blown diatoms from both planktonic/benthic freshwater (80%) and planktonic marine (20%) sources. The freshwater species included aerophilic species (from damp environments), key indicators of exposed, environments and found widely in the Arctic. We observe that both total diatom numbers and species composition changes rapidly over time (i.e. decadal timescales), similar to other ice-core proxies, and with higher total numbers/yr between about 1780 and 1850 AD. Further analysis is required to establish a link to specific environmental variables, which could include aridity, wind strength or sea ice cover. We hypothesise that similar lower altitude, coastal ice cores from Greenland and Canada could be useful diatom repositories in the Arctic region.
The potential of Satellite and model derived precipitation and soil moisture for estimation of landslide hazard thresholds in Rwanda
Authors: Uwihirwe Judith , Riveros Alessia , Sadeghi Tehrani Faraz , Sperna Weiland Frederiek , Hrachowitz Markus , A. Bogaard Thom A. Bogaard
Published: March 2022

A combination of extreme environmental conditions such as high soil moisture content and heavy or prolonged precipitation contribute to landslide initiation in mountainous areas worldwide. On-site soil moisture monitoring equipment and rain gauge have been widely used to record these variables despite the sparse spatial coverage. Satellite‐based technologies provide estimates of rainfall and soil moisture over large spatial areas sufficient to be explored for landslide hazard assessment in data scarce regions. In this study, we used statistical metrics to compare the gauge based to the satellite precipitation products: TRMM42, CHIRPS, PERSIANN-CDR, GLDAS-2.1, CFSV2, GPM-IMERG, and ERA-5 and assess their performance. Similarly, high resolution satellite and hydrological model derived soil moisture was compared to the automated soil moisture observations at Rwanda weather station sites to assess the usefulness in empirical landslide hazard assessment thresholds in Rwanda. Based on statistical indicators, the NASA GPM based IMERG showed the highest skill to reproduce the main spatiotemporal precipitation patterns. Similarly, the satellite and hydrological model derived soil moisture broadly reproduce the in situ measured soil moisture. The landslide explanatory variables from IMERG satellite precipitation; event rainfall volume E and Duration D in bilinear thresholds framework reveal promising results with improved landslide prediction capabilities in terms of true positive alarms ~80-90% and low rate of false alarms ~14-16%. However, the incorporation of satellite and model derived antecedent soil moisture to the empirical landslide hydro-meteorological thresholds showed no significant improvement. This may be attributed to the probable long and no constant timescale of the defined landslide triggering events that could be shortened to further improve the landslide prediction and support the early warning system development in Rwanda.
Quantifying the uncertainty of biofouled microplastic motion in vortical flows representative of turbulence in the upper ocean
Authors: Kreczak Hannah , Willmott Andrew , Baggaley Andrew
Published: March 2022

The majority of buoyant, marine microplastics are missing from the ocean surface, however, their presence has been observed throughout the ocean water-column and in seafloor sediments. The accumulation of microorganisms on the microplastics' surface, termed biofouling, has been proposed as a mechanism contributing substantially to their removal from the ocean surface by changing the particles' buoyancy. Mathematical models outlining the biofouling processes on microplastics have been implemented in General Ocean Circulation models (OGCMs) in an effort to predict their long-time transport in the ocean. The resolution of OGCMs is extremely course and sub-grid turbulent motions so far have either been neglected or parameterised via stochastic perturbations through an eddy diffusivity term. Accurately capturing the sub-grid turbulent motions, and quantifying the uncertainty they introduce to particle trajectories, is critical to establishing predictive maps of biofouled microplastic transport in the ocean. As an intuitive first step using representative models of oceanic, turbulent motions to define a more accurate parameterisation, we use the Maxey-Riley-Gatignol equations for the motion of small particles and analyse the trajectories of both individual and many particles with increasing, negative buoyancy in steady and unsteady deterministic, Taylor-Green vortex flow. We quantify the uncertainty these vortical flows introduce across parameter ranges of interest to microplastic and oceanic turbulence, finding that coherent turbulent structures, such as Langmuir circulations, could lead to errors in vertical position prediction on the order of kilometres. Comparatively, a stochastic parameterisation is shown to significantly under-approximate the dispersion of particles from the vortical flow, suggesting that the current standard using an eddy diffusivity term to capture turbulent mixing may be too simplistic.
Planetary wave activity observed in atmosphere-ionosphere system over low latitudes
Authors: Jadhav Ashish , Subramanian Gurubaran , Patil Parashram
Published: March 2022

The coupled response of the atmosphere-ionosphere system to planetary waves propagating from below has been observed through MF and Meteor radars at different longitudes along with the ground geomagnetic data from 23 stations of Northern (NH) and Southern Hemisphere (SH) during northern winter months of January, 2015 and 2017. The focus is on delineating the quasi-2-day (Q2DW) and quasi-6-day wave signatures in the mesosphere-lower thermosphere (MLT) and in ionospheric Sq currents besides deciphering their effects on the overall neutral dynamics at low latitudes. Analysis extended to longitudinally separated stations confirms the penetration of these planetary waves into the ionosphere either directly or indirectly through interaction with other wave modes in the MLT region.
Analysis of survival probability on multiple species using metapopulation model
Authors: Kim Eun sub , Mo Yong won , Kim Ji yeon , Lee Dong kun
Published: March 2022

The ecological concept of the meta population helps evaluate the effectiveness of conservation areas (Soule et al., 1988), and is used as a useful tool for evaluating responses between individuals to artificial stressors such as urbanization, habitat destruction, and fragmentation (Kawecki. 2004). In particular meta population model can help increase the accuracy of population estimation across various spatial scales and explain several interactions populations (Walther et al., 2002; Faborg, 2014). Previous studies have demonstrated that habitat destruction and fragmentation caused by urbanization can affect the viability of species in habitats due to reduced fertility and mobility, but papers on the selection of conservation areas can increase the viability of multi species according to the changing surroundings are insufficient. Therefore, this study analyzed the possibility of multi species surviving in the habitat using a meta population model for conservation area scenarios and analyzed the effect of habitat pattern changes on each population from various perspectives.

In order to analyze the survival probability of multi species in habitats by conservation area scenario, (1) setting the 15 virtual habitat spaces within 160ha, (2) Big & Small conservation scenarios considering habitat area, connection, and connection, (3) collecting and estimation of migration rate, home range, dispersal distance for biological species for analyzing the possibility of extinction by population. Finally, the change in the population of each population during period t was analyzed using the meta population model.

Overall, when the Big Conservation area was applied, the probability of extinction of all species was low, followed by the Big+Connectivity scenario. In addition, the probability of survival was similarly derived in the Small scenario and the Connectivity scenario. However, the preferred conservation scenarios for each classification population group were different depending on the conservation scenario. In particular, birds had a high probability of extinction in the small scenario, while small mammals had a low probability of extinction. Through this study, the effect on the change in the number of multi species according to the conservation area scenario was analyzed, which is expected to be used to evaluate the validity and effectiveness of setting up a conservation area in the future.
Eddy identification from along track altimeter data using deep learning: EDDY project
Authors: Abulaitijiang Adili , Bolmer Eike , Roscher Ribana , Kusche Jürgen , Fenoglio Luciana , Stolzenberger Sophie
Published: March 2022

Eddies are circular rotating water masses, which are usually generated near the large ocean currents, e.g., Gulf Stream. Monitoring eddies and gaining knowledge on eddy statistics over a large region are important for fishery, marine biology studies, and testing ocean models.

At mesoscale, eddies are observed in radar altimetry, and methods have been developed to identify, track and classify them in gridded maps of sea surface height derived from multi-mission data sets. However, this procedure has drawbacks since much information is lost in the gridded maps. Inevitably, the spatial and temporal resolution of the original altimetry data degrades during the gridding process. On the other hand, the task of identifying eddies has been a post-analysis process on the gridded dataset, which is, by far, not meaningful for near-real time applications or forecasts. In the EDDY project at the University of Bonn, we aim to develop methods for identifying eddies directly from along track altimetry data via a machine (deep) learning approach.

At the early stage of the project, we started with gridded altimetry maps to set up and test the machine learning algorithm. The gridded datasets are not limited to multi-mission gridded maps from AVISO, but also include the high resolution (~6 km) ocean modeling simulation dataset (e.g., FESOM, Finite Element Sea ice Ocean Model). Later, the gridded maps are sampled along the real altimetry ground tracks to obtain the single-track altimetry data. Reference data, as the training set for machine learning, will be produced by open-source geometry-based approach (e.g., py-eddy-tracker, Mason et al., 2014) with additional constraints like Okubo-Weiss parameter and Sea Surface Temperature (SST) profile signatures.

In this presentation, we introduce the EDDY project and show the results from the machine learning approach based on gridded datasets for the Gulf stream area for the period 2017, and first results of single-track eddy identification in the region.
A Student-Led Project for the Design of an Imaging CubeSat Payload
Authors: Reid David , Timperley Louis , Pike Oliver , Etchells Tom , Hollingdale James , Goodwin Tom , Exton David , Labia Franco , Stonkus Vilius , O'Donnell Michael , Leach Charlie , Aadhithya Ravikumar Vishnu , Proud Will , Sutlieff Gary , Aplin Karen , Berthoud Lucy , Sarua Andrei , Schenk Mark , Watson Matthew
Published: March 2022

Volcanic ash presents a challenge for the aviation industry. Volcanic ash is semi-transparent, absorbing in the 8-12 micron window. 3D information is needed to be able to back-calculate dose – this is a key parameter in managing airspace. To recreate the ash cloud, multiangle observations are required – making a nadir-pointing satellite ideal to perform observations for this purpose. Other mission objectives using the same instruments can also be realised, for example, as volcanic ash clouds are the primary target, there is the possibility to map new magma extrusions, lava and pyroclastic flow movements. Thermal infrared data has also previously been used to observe volcanic cycles and better understand their behaviour. There is also the possibility of including forest fires as targets of opportunity. The images required for 3D construction of ash clouds can also be used to create digital elevation models of terrain around volcanos which have application in disaster management and planning.

A CubeSat mission - Pointable Radiometer for Observing Volcanic Emissions (PROVE) - is proposed to monitor the ash cloud using both thermal infrared and visual cameras. All requirements and components were determined by students through trade-off studies. Each work package was undertaken by undergraduate and postgraduate students (both as part of research projects and on a voluntary extracurricular basis) supervised by academics. The resulting 1U+ payload consists of a thermal infrared camera (FLIR Tau 2 with a 50mm lens), and 2 visual cameras (a narrow field of view Basler ace ac5472-5gc with a Kowa LM75HC lens, and a 5MP Arducam with a 40 degree lens as a wide field of view instrument). Alongside this, a payload computer to communicate with the cameras and store data was selected (the Beaglebone Black Industrial) with a custom PCB providing connections to the instruments and bus. The software to operate the payload takes the form of a custom scheduler for an imaging pass, sending commands to the camera systems (and to the bus) to take the required multiangle images for ash cloud reconstruction.

The payload is currently in the final design and testing stage, with vibration and vacuum testing, as well as FlatSat testing before the final manufacture and integration of the payload. There is the possibility of a UK launch later this year.
Summary of integrative and Comprehensive Understanding on Polar Environments (iCUPE) project results
Authors: Petäjä Tuukka ,   iCUPE project team
Published: March 2022

The Horizon-2020 iCUPE (Integrative and Comprehensive Understanding on Polar Environments; https://www.atm.helsinki.fi/icupe) was a science driven the ERA-PLANET (European network for observing our changing planet; http://www.era-planet.eu) Programme Thematic Strand-4 project. The iCUPE overall aim was to evaluate and present a holistic understanding of impacts of various increasing human activities on the polar areas, and especially in the Arctic regions. The iCUPE main scientific impact is related to improved understanding and new knowledge about local and remote sources of Arctic air pollutants, including short-lived climate forcers and their precursors as well as their sinks, and improved quantification of the life cycle of mercury, heavy metals, black carbon and persistent organic pollutants. In addition, iCUPE examined changes in the Arctic snow and ice surfaces, vegetation, biomass characteristics, mapped out the development of natural resources extraction and delivered the new first impact assessments of the future exposure scenarios of pollutants in the Arctic regions. During iCUPE project lifetime the consortium worked on combining integrated in-situ and satellite Earth Observation with multi-scale modelling platform by: (1) synthesizing data from comprehensive long-term measurements, intensive campaigns and satellites, collected during the project or provided by on-going international initiatives; (2) relating the observed parameters to impacts; and (3) delivering novel data products, metrics and indicators to the stakeholders concerning the environmental status, availability and extraction of natural resources in the polar areas. Overall, iCUPE collected a significant body of knowledge, including 24 novel datasets, methods, algorithms and published more than 100 research papers. A summary of the iCUPE project obtained results will presented and discussed.
Increasing lake levels on the central Tibetan Plateau since 1920 CE inferred by a sub-fossil chironomid record from Shen Co
Authors: Rigterink Sonja , Echeverría-Galindo Paula , Martínez-Abarca Rodrigo , Massaferro Julieta , Hoelzmann Philipp , Wünnemann Bernd , Laug Andreas , Pérez Liseth , Kang Wengang , Börner Nicole , Schwarz Anja , Peng Ping , Wang Junbo , Zhu Liping , Schwalb Antje
Published: March 2022

Lakes on the Tibetan Plateau are especially vulnerable to global warming and increasing temperatures but are also sensitive to changes in the atmospheric circulation such as the Westerlies and the Asian Summer Monsoon, which are main drivers of precipitation on the Plateau. Shallow lake environments in such high-altitudinal areas, which are not directly influenced by meltwater supply, are excellent study sites to determine changes in precipitation and evaporation. Here, we present a 300-year high-resolution chironomid record from the high-altitude (> 4,733 m a.s.l.), saline (9 g L-1) and shallow (~ 5 m water depth) lake Shen Co (N 31° 00’, E 90°29’), situated on the southern part of the central Tibetan Plateau. We combined chironomid assemblages with sedimentological, mineralogical and geochemical data from a short sediment core (37.5 cm) to detect hydrological changes since 1830 CE. Our study revealed three different periods in Shen Co: (1) from 1830 until 1920 CE sediments were void of chironomids, suggesting dry conditions leading to low lake levels, high salinity resulting from low runoff and high evaporation rates, supported by increasing Mg/Ca and Sr/Rb ratios of the sediments; (2) a humid phase characterized by the appearance of Acricotopus indet. morphotype incurvatus from 1920 until 1950 CE, indicating rising lake levels caused by higher runoff and decreased evaporation, also supported by sediment analysis with increasing TOC and Ti as well as a decreasing Ca/Ti ratio; and (3) a continuous water level rise from the 1950s onwards with a lake level maximum as well as high macrophyte growth since the beginning of the 21th century, supported by the dominance of Procladius and the phytophilic taxon Psectrocladius sordidellus-type. We compared our results with paleoclimate records from the Tibetan Plateau, based on e.g. ice core δ18O, pollen, tree rings, indicating warmer and wetter climate conditions on the central Tibetan Plateau during the last ~ 100 years. Our findings highlight that chironomid records from shallow lake environments are excellent indicators of lake level variations as well as changes in macrophyte vegetation.
Variability of low-level clouds over the southern oceans
Authors: Bazantay Clément , Jourdan Olivier , Mioche Guillaume , Delanoë Julien , Cazenave Quitterie , Uitz Julia , Sellegri Karine
Published: March 2022

Climate model simulations of cloud radiative properties over the Southern Ocean (SO) show that clouds reflect too little solar radiation compared with observations. This results in large errors in the modelled sea surface temperature, atmospheric circulation and climate sensitivity. Low-level (LL) mixed-phase clouds (MPCs) in the cold sectors of extratropical cyclones are identified as the main contributor to the SO radiation bias.

In this study, LL clouds are investigated between 40°S and 82° S to provide a new insight into their geographical distribution, as well as their spatial and temporal variabilities. The methodology relies on DARDAR products which exploits the synergy of CALIPSO's lidar and CloudSat's radar space-borne remote sensing observations. Based on DARDAR cloud-type products, a cloud classification program was developed to establish cloud spatial and temporal distributions.  This study concerns all types of cloud, including MPCs and supercooled-water containing clouds. The mean seasonal LL cloud cover for 2007-2010 over oceans (including sea-ice) varies from 64.4% in winter to 68.4% in fall. Larger cloud covers are observed between 50°S and 65°S where clouds are present more than 80% of the time. Dividing the studied area into smaller regions allowed to extract homogeneous sectors in term of cloud coverage. This analysis draw attention on some regions, such as the Tasman Sea sector that undergoes the highest seasonal variations for MPC and USLC occurrence, and the Argentinian coasts that presents important differences with other regions at the same latitudes. Over the Southern Ocean, the Weddell Sea sector stands out with a relatively low LL cloud occurrence.

Statistical analyses were carried out to determine the influence of the meteorological and biological conditions on cloud occurrence. Even though air temperature drives all cloud-type occurrences, it was found that the lower-tropospheric stability (LTS) is a good predictor of ice-cloud occurrence between 40°S and 50°S, particularly. With biological activity, first results indicate strong correlations with cloud occurrence, where chlorophyll-a, nanophytoplankton and particulate organic carbon concentrations are investigated between 40°S and 60°S.
Particulate organic carbon composition and landscape characteristics in the Peel River Watershed, Canada
Authors: Keskitalo Kirsi , Speetjens Niek , Overduin Paul , Westermann Sebastian , Miesner Frederieke , Sachs Torsten , Nitze Ingmar , Bröder Lisa , Haghipour Negar , Eglinton Timothy , Vonk Jorien
Published: March 2022

Rapid warming of the Arctic is accelerating thaw of permafrost, which mobilizes organic carbon (OC). Remineralization of this carbon can contribute to further climate warming. The Peel River watershed is underlain by continuous and discontinuous permafrost and covers a diverse set of landscapes from wetlands to barren mountainous areas. Part of the watershed undergoes abrupt permafrost thaw that releases particulate OC (POC) to the fluvial system. In this study, we couple landscape characteristics to river POC to better understand its spatial variability and the changes imposed on the watershed by permafrost thaw. We sampled POC in July-August 2019 in the Peel River main stem and its tributaries (total n=~120) and used carbon isotopes and lipid biomarkers to characterize its composition and trace its sources. Our first results indicate a compositional diversity within the watershed as POC ranges between <0.1 and 2.1 mg L-1, δ13C-POC from -36.7 to -26.5‰ and Δ14C-POC from -906.4 to -43.5‰. Ongoing changes in the watershed can be traced within its waters, and may help us to decipher how it is changing and may change in the future.
A machine learning approach for refining ECHAM-HAMMOZ-derived PM2.5
Authors: Miinalainen Tuuli , Kokkola Harri , Lipponen Antti , Lehtinen Kari E. J. , Kühn Thomas
Published: March 2022

In this study, we present our findings for correcting global model-derived surface fine particulate mass (PM2.5) concentrations with a machine learning approach. We simulated the PM2.5 concentrations with an aerosol-climate model ECHAM-HAMMOZ, and trained a machine learning model to downscale the PM2.5 concentrations modelled for an Indian mega city, New Delhi. This way, we are able to utilize a global atmospheric model for analyzing aerosol emission mitigation effects on both Earth's energy budget and local air quality.

Similarly as with many other global-scale models, ECHAM-HAMMOZ underestimates surface PM2.5 at several urban locations. One apparent explanation for this is the coarse grid resolution of global climate models, which results in averaged aerosol concentrations over a much larger area than what urban cities typically cover. Therefore, due to averaging over a large grid box, the very high peak concentrations from urban areas can be evened out. Furthermore, the input fields describing aerosol emissions might lack information of some local emission sources, which can as well affect the simulated surface air pollution levels.

We used the random forest (RF) regression algorithm in order to downscale ECHAM-HAMMOZ-derived surface PM2.5 concentrations towards measured PM2.5 values from the New Delhi capital region in India. In addition, we applied the trained RF model to additional simulations where we had future anthropogenic aerosol emissions according to a business as usual scenario and a mitigation scenario. This allowed us to evaluate the effects of aerosol emission reductions on both global radiative balance, and on local air quality in New Delhi.

The obtained results indicate that surface PM2.5 concentrations from RF prediction correlate with the measured PM2.5 concentrations much better than the original ECHAM-HAMMOZ particulate concentrations for New Delhi region. However, with the current setup and input variables, the PM2.5 concentrations produced by the RF model seems to be lacking some of the short-term variations and very low and high values.

All in all, the downscaling method used in this project shows very promising potential, but requires further adjustment with the selection of input variables and the RF hyperparameters.
Modelling the impacts of water harvesting and climate change on rainfed maize yields in Senegal
Authors: Castelli Giulio , Setti Andrea , Villani Lorenzo , Ferrise Roberto , Bresci Elena
Published: March 2022

The agricultural sector of Senegal is prone to drought and climate change impacts. Despite this, the country counts less than 5% of irrigated lands, suggesting that its national agriculture is still strictly dependent on the rainy season. Moreover, rainfall is characterized by the presence of great variability, both on interannual and interdecadal timescales. In this framework, a research gap is represented by the lack of analyses on how much the current agricultural practices can be resilient, and on what water management strategies can be effective against climate change.

Using FAO’s AquaCrop crop-growth model, made up of a set of four sub-model components (climate, crop, soil, and management) to simulate a crop cycle, we simulated plausible climate change scenarios at different fertility levels, testing the efficiency of tied ridges water harvesting for the maize crop in the Fatick region, Senegal. Non-conservative parameters were adjusted with crop data collected within the project "Rain, Forest and People" of the International Rainwater Harvesting Alliance (IRHA, https://www.irha-h2o.org/en/projects/la-pluie-la-foret-et-les-hommes) while calibration and validation were performed with regional yield data.

Considering the current climatic scenario and soil fertility, tied ridges did not significantly impact the maize yields. Rainfall amount was enough for maize production and to avoid high water stresses along the cropping season. Under climate change scenarios, high reductions in yield were registered up to 70% in optimally fertilized soil and 50% in conditions of fertility stress.  Tied ridges only slightly increased yields up to 3.8% when a high reduction of rainfall occurred. When also considering the occurrence of dry spells in addition to climate change, maximum yield reductions do not exceed the values found without dry spells. However, in such context, tied ridges water harvesting performed better against climate change, especially under full fertilization management.

Our results highlighted how the current maize production in the Fatick region of Senegal is sustainable in the current climate scenario, while it could be potentially impacted by climate change in the near future. In a pessimistic climate change scenario with dry spells occurring in the rainy season, in-situ water harvesting has the potentiality to avoid excessive crop losses.
Multi-site rock slope thermal monitoring: Initial results
Authors: Racek Ondřej , Blahůt Jan , Hartvich Filip
Published: March 2022

This presentation is dedicated to a short description of a combined rock slope thermal monitoring system. The newly designed system is affordable and modular, which predisposes it to installation at multiple sites. This system is being used to monitor four different rock slopes in Czechia for a period of up to 3 years. Slopes differ by lithology, structural setting aspect and modes of instability. The monitoring system consists of a climate station, rock mass surface zone thermal monitoring and unstable blocks crackmeter monitoring. Since 2018 we have instrumented 11 blocks, which differ in terms of shape, volume and mode of destabilization. Analyses of crackmeter, thermal and climatic time-series showed influences of weather and temperature cycles on the crackmeter aperture. Consequently, short-term (diurnal) and medium-term (annual) temperature cycles on the rock slope surficial zone were described. Data show high variability linked to the partial blocks geometry and rock slope properties.
Exploring hemispheric tectonics on tidally-locked super-Earths
Authors: Meier Tobias G. , Bower Dan J. , Lichtenberg Tim , Hammond Mark , Tackley Paul J.
Published: March 2022

Super-Earth LHS 3844b is a rocky exoplanet with a radius around 1.3 Earth radii. Its thermal phase curve suggests that the dayside temperature is around 1040 K and the nightside temperature is around 0 - 700 K, indicating inefficient atmospheric heat circulation. Therefore, this planet most likely lacks an atmosphere. In a previous study, we have shown that such a strong surface temperature dichotomy can lead to a so-called hemispheric tectonic regime. In such a regime, a cold downwelling forms preferentially on one side and hot upwellings are getting pushed towards the other hemisphere. 
GJ 486b is a super-Earth that is very similar to LHS 3844b in terms of size and it is currently unknown whether this planet has an atmosphere. In this study, we are investigating under which circumstances hemispheric tectonics can operate on GJ 486b. We also investigate the stability of hemispheric tectonics. 

We run 2D geodynamic simulations of the interior mantle flow using the mantle convection code StagYY. The models are fully compressible with an Arrhenius-type viscosity law where the mantle is mostly composed of perovskite and post-perovskite. The lithospheric strength is modelled through a plastic yielding criteria and the heating mode is either basal heating only or mixed heating (basal and internal heating). 
We use general circulation models (GCMs) of potential atmospheres to constrain the surface temperature assuming different efficiencies of atmospheric heat circulation. 

We find that a hemispheric tectonic regime is also possible for surface temperature contrasts with moderate heat redistribution. The location of the strong downwelling depends on several factors such as the surface temperature contrast and strength of the lithosphere. By reducing the temperature contrast, the location of the downwelling becomes less stable and it can start to move from one side towards the other over very long timescales (Gyrs). Our results show that hemispheric tectonics could operate on tidally-locked super-Earths, even if the surface temperature contrast between the dayside and nightside is not as strong as for LHS 3844b. Upwellings that rise preferentially on one hemisphere could lead to generation of melt and subsequent outgassing of volatiles on that side. Imprints of such outgassing on the atmospheric composition could possibly be probed by current and future observations such as JWST, ARIEL or the ELT. 