bluuebunny/crossref_metadata_2025 huggingface dataset:
Understanding the Barrier Effects of the Maritime Continent on MJO Prediction
Authors: Savarin Ajda , Chen Shuyi
Published: March 2022

The Madden-Julian Oscillation (MJO) is one of the leading sources of tropical and extra-tropical predictability on subseasonal-to-seasonal timescales, but numerical models often suffer from systematic errors in capturing the MJO dynamics. Large-scale convection associated with the MJO is initiated over the Indian Ocean and propagates eastward across the Maritime Continent (MC) and into the western Pacific. As an MJO event enters the MC, it often weakens or completely dissipates due to complex interactions between the large-scale MJO and the MC landmass and its topography. This MC barrier effect is responsible for the dissipation of 40-50% of observed MJO events, though the exact nature of the barrier effect is unclear. Common mechanisms include the physical barrier of the islands of the MC, and the dynamical barrier of strong diurnally driven circulations that exist around those islands. The MC barrier effect is often exaggerated in when it comes to MJO prediction.

In this study, we examine convection-permitting, atmosphere-ocean coupled model simulations of an MJO event to determine how the MJO responds to physical and dynamical changes implemented over the MC region. In addition to the control simulation with real topography, we introduce two idealized simulations – (1) where we flatten the topography of the MC to sea level, but leave the land-sea distribution as is, and (2) where we entirely remove the MC islands and replace them with a 50-m deep ocean. How the MJO responds to the implemented changes can help us determine whether some physical processes that occur over the MC are more detrimental to MJO propagation than others. The differences between the control simulation and the first scenario can tell us about the physical barrier effect of the MC on MJO propagation. The complete removal of land in the second scenario also removes the diurnal changes associated with air-sea boundaries (e.g., land-sea breezes and convergence zones between islands), exploring whether the barrier effect of the MC on the MJO is more dynamically driven.

Results show that flattening the MC terrain only has a small impact on large-scale MJO characteristics. However, as expected, removing the land, and diurnal cycle associated with it, drastically smooths the MJO’s propagation and the produced MJO shows no sign of dissipation over the MC region. We examine the model simulations to gain insight on what physical processes are behind the changes among model simulations and to expose some modeling difficulties that could contribute to numerical models’ exaggerating the effects of the MC barrier effect.
Phosphorus and Fine Particle Retention in Agricultural Headwater Streams
Authors: Field Hannah R. , Sawyer Audrey H. , Welch Susan A. , Benefiel Ryan K. , Mathie Devan M. , Hood James M. , Pawlowski Ethan D. , Karwan Diana L. , Kreiling Rebecca M. , Johnson Zackary I. , Hanrahan Brittany R. , King Kevin W.
Published: March 2022

In many poorly drained agricultural regions, humans have introduced expansive networks of subsurface tile drains and straightened headwater streams to improve drainage. These networks serve as a direct link between cropland and larger streams and rivers, but the transport and retention of nutrients like phosphorus (P) in these networks is not well understood. Here we evaluate transport and retention of dissolved P and fine particles (which sorb dissolved P) within an agricultural drainage ditch in the Maumee River Basin in northeastern Ohio, USA. We conducted three constant rate injections of conservative salt (Cl as NaCl), dissolved P (KH2PO4), and a fluorescent fine particle (Dayglo AX-11-5 Aurora Pink®) following precipitation events in the spring (May), summer (July), and autumn (December). We model the breakthrough curves using the Continuous Time Random Walk (CTRW) approach to quantify solute and particle transport behavior. Preliminary analysis of Cl breakthrough curves indicates that in-stream velocities were slightly greater in spring (0.079 m/s compared with 0.039 m/s in summer and 0.060 m/s in fall), and conservative solute retention was also greatest in spring, as indicated by residence time behavior (tail power-law slope of -1.73 compared with -1.23 in summer and -1.59 in fall). Preliminary analysis of dissolved P breakthrough curves indicates that the nutrient spiraling length was longer in the spring (4070 m) and decreased in the summer (1560 m). Vegetation stands throughout the stream were denser in the summer and autumn and likely influenced P transport through both physical and biological processes. With the increasing frequency and severity of harmful algal blooms in major waterbodies that receive P from agricultural lands, it is crucial to understand how P moves through highly modified agricultural drainage networks. Tentatively, this study indicates that aquatic vegetation drives biophysical processes in drainage ditches that dictate seasonal nutrient export to larger waterbodies.
Enhanced Quasi-6-Day Wave during the 2019 Southern Hemisphere SSW and its modulation of diurnal tides and gravity waves 
Authors: Qiao Zishun , Liu Alan Z. , Pedatella Nick , Stober Gunter , Reid Iain , Fuentes Javier , Adami Chris
Published: March 2022

A newly established multi-static meteor radar network, CONDOR (31.2ºS,70.0ºW), provides the capability to resolve wind and temperature oscillations over a broad range of periods, calculate E-P flux of planetary waves and investigate the short-term variability in the 80-100 km MLT region. In this study we present results of an enhanced westward wavenumber 1 Q6DW activity and its modulation with the amplified diurnal tides and gravity waves (GW) meridional wind variance during a rare minor SH SSW in 2019, using two SH midlatitude meteor radar observations and a recently developed 3DVAR algorithm. This algorithm creates a tomographic reconstruction of the 3D wind field based on optimal estimation technique and Bayesian statistics and is particularly suitable for investigating GW dynamics on regional scales. Furthermore, we present the first results of meteor radar observed Q6DW E-P flux and its comparison with SD-WACCM-X simulated Q6DW E-P flux. The encouraging agreement demonstrated that this SSW-related Q6DW activity had a significant impact on the dynamically coupled MLT region at SH midlatitude.
The Copernicus Imaging Microwave Radiometer (CIMR): A new view of the Cryosphere
Authors: Donlon Craig , Midthassel Rolv , Sallusti Marcello , Trigganese Mariel , Fiorelli Benedetta , Accadia Christophe
Published: March 2022

This presentation describes the Copernicus Imaging Microwave Radiometer (CIMR) Sentinel expansion mission. The mission is designed to provide measurement evidence in support of developing, implementing, and monitoring the impact of the European Integrated Policy for the Arctic. Since changes in the Polar regions have profound impacts globally, CIMR will provide a new view of the cryosphere using a suite of unique low-frequency, yet high spatial resolution, microwave radiometer measurements over the high latitudes and the entire global domain. Products will be provided within 3 hours of sensing and for specific operational activities, within 1 hour over specific regions. CIMR will serve users in the Copernicus Ocean, Land and Climate Services fueling down-stream cryosphere applications. The primary instrument is a conically scanning low-frequency, high spatial resolution multi-channel microwave radiometer. A dawn-dusk orbit and large swath width of ~2000 km ensures 95% global coverage each day with a single satellite. Channels centred at L-, C-, X-, Ku- and Ka-band are fully polarised with effective spatial resolution of ≤60 km, ≤15km, ≤5 km and <5 km (goal:4km) respectively. On-board processing provides robustness against radio frequency interference and enables the computation of modified 3rd and 4th Stokes parameters for all channels. This paper reviews the CIMR mission, anticipated performances and the expected Level-2 products that will be provided including sea ice concentration, sea surface temperature, thin sea ice thickness, sea surface salinity and wind speed over the ocean amongst others . In addition, synergies with other Copernicus missions, notably the CRISTAL mission, will be highlighted for cryosphere applications.
An aeromagnetic survey over the volcanic island of Surtsey off the south coast of Iceland
Authors: sayyadi sara , Gudmundsson Magnús T , White James D.H. , Jónsson Thorsteinn , Jackson Marie D
Published: March 2022

Submarine volcanic activity was observed in the Vestmannaeyjar archipelago off the south coast of Iceland in November 1963, at a location where the pre-eruption oceanic depth was 130 m.  The eruption continued until July 1967. As a result of the eruption, a volcanic island, Surtsey, and its short-lived satellite islands (Surtla, Syrtlingur, and Jólnir) were created.  The progression of the eruption was very well documented at the time.  However, data on structures below sea level has been limited to drillholes on the rim of the Surtur crater on the main Surtsey island.  In order to study the existence and possible location of pillow lava from the initial phases of the eruption and shallow intrusions within and below the edifices formed in 1963-1967, a six-hour-long aeromagnetic survey was completed in October 2021 over the Surtsey area. The survey is done using a Geometrics MagArrow drone magnetometer, here adapted for operation while fixed to an aircraft. The survey covered 60 km2.  The spacing between profiles was 200 m and the flight elevation 100 m a.s.l. The MagArrow has a sampling frequency of 1000 Hz, which for an aircraft flying at 50 m/s gives a reading every 5 cm. To remove noise and perturbations from the aircraft, the data is low-pass filtered in two steps, firstly by averaging 50 measurements providing 20 Hz data, then by applying low pass filter with a cutoff frequency of 0.225 Hz, removing wavelengths smaller than 200-250m.  Initial data processing indicates some variations in the sources to the anomalies observed.  Major anomalies arise from the subaerial lavas on Surtsey itself, while the submarine remnants of the island Syrtlingur, active in 1965, show no anomalies.  This suggests that it is exclusively made of tuffs with no significant intrusions, similar to the structure of Surtsey itself below sea floor according to the drill cores obtained in 1979 and 2017.  In contrast, a clear anomaly is observed over the submarine remnants of the satellite island Jólnir, which was formed over several months in 1966. Apparently, this anomaly can only be explained by a magnetic body located no deeper than at 100 m depth below the seafloor at the eastern part of Jólnir, the same location as the vent active in 1966. 
Improvements of PBL scheme in INMCM5 climate model.
Authors: Debolskiy Andrey , Mortikov Evgeny , Glazunov Andrey
Published: March 2022

Locally one-dimensional ABL model of the moderately stable and highly stable boundary layer of the atmosphere were evaluated with the data obtained from numerical experiments with eddy-resolving turbulence models. It is shown that the best results are obtained by parametrizations which maintain turbulence at large gradient Richardson numbers.  These parametrizations of turbulent diffusion for stable stratification were introduced into the INM RAS Earth System model [1].

Based on a comparison with the reanalysis data, it is shown that an improved model of turbulence in the boundary layer reduces the average error in reproducing the current climate in high latitudes.

Authors want to acknowledge partial funding by Russian Foundation for Basic Research (RFBR project 20-05-00776) and support from Russian Science Foundation (RSF grant 20-17-00190).

1. Volodin, E. M., et al. "Simulation of the present-day climate with the climate model INMCM5." Climate dynamics 49.11 (2017): 3715-3734.
Reduced-complexity modeling as a valuable tool for studying the coastal impacts of climate change
Authors: Álvarez-Cuesta Moisés , Toimil Alexandra , Losada Iñigo
Published: March 2022

Forecasting the coastal response to climate change is a complex problem due to the nonlinear interplays at multiple scales between the different hazards, i.e. flooding and erosion. To handle this challenge, the use of simple and computationally efficient, yet accurate tools is required. The combination of reduced-complexity shoreline modelling and efficient physics-based flood spread models is an appropriate way to project coastal risks under climate scenarios, being a balanced solution regarding computational time and accuracy. We present a methodology comprised by an efficient wave downscaling methodology, the recently developed shoreline evolution model IH-LANS (Alvarez-Cuesta et al., 2021a), flood-spread modeling and an ensemble treatment of climate-related uncertainty as in (Alvarez-Cuesta et al., 2021b) to forecast the evolution of coastal risk. The methodology is applied at a vulnerable low-lying coastal area in Murcia, Spain and it allowed to highlight the coastal hotspots and the definition and evaluation of adaptation measures. This application strengthen the suitability of reduced-complexity modeling to guide decision making in complex coastal settings.

 

Alvarez-Cuesta, M., Toimil, A., & Losada, I. J. (2021a). Modelling long-term shoreline evolution in highly anthropized coastal areas . Part 1 : Model description and validation. Coastal Engineering, 169(July), 103960. https://doi.org/10.1016/j.coastaleng.2021.103960

Alvarez-Cuesta, M., Toimil, A., & Losada, I. J. (2021b). Modelling long-term shoreline evolution in highly anthropized coastal areas . Part 2 : Assessing the response to climate change. Coastal Engineering, 168(July), 103961. https://doi.org/10.1016/j.coastaleng.2021.103961
Very long electric field disturbances induced by dust impact observed by the Solar Orbiter/RPW
Authors: Morooka Michiko , Khotyaintsev Yuri , Maksimovic Milan , Soucek Jan , Pisa David
Published: March 2022

Transient electric field perturbations are commonly observed when the interplanetary dust grains impact spacecraft, and their characteristics are well-studied. The signals are interpreted as due to the plasma expansion at the impact site and last typically in the order of micro-to milli-seconds. Radio and Plasma Wave (RPW) Instrument onboard Solar Orbiter can observe grains with a dedicated mode to capture such short-lived signals by the dust in the inner Heliosphere. On the other hand, a large impact can cause electric field disturbance for a longer time in tens of seconds. The long signals are observed in the low-frequency range (<10 kHz) and found more frequently during the inbound of the Solar Orbiter excursion. We will discuss the plasma and spacecraft conditions for the long durational impact signals.
Cuba's northern offshore: a witness to geodynamics evolution of the northern boundary of the Caribbean plate
Authors: Oliveira de Sa Alana , Leroy Sylvie , D'Acremont Elia , La Fuerza Sara , Mercier de Lepinay Bernard
Published: March 2022

The northern boundary of the Caribbean plate is characterized by the oblique collision between the Caribbean (CAR) and North American (NOAM) tectonic plates. The progressive counterclockwise rotation of the two plates accompanying the eastward translation of NOAM vs. CAR is responsible for the increasing obliquity of the collision between these two plates. Consequently, successive southward jumps of major strike-slip faults accommodate the eastward escape of the Caribbean plate and the collisional indentation against the Bahama Banks. During this process, Cuba was progressively welded to the North American Plate. Several strike-slip corridors record this diachronous collision as major left-lateral transfer zones in Cuba: Eastern Yucatan Margin (Upper Cretaceous), Pinar-Varadero (Paleocene), La Trocha (early Eocene), Cauto-Nipe (middle/late Eocene), and Oriente Fault Zone (early Oligocene). The nature and age of the related tectonic events of these tectonic corridors were widely studied onshore. However, offshore northern Cuba remains relatively unknown. We provided a first offshore description of northeastern Cuba based on a multi-channel seismic reflection and swath-bathymetric dataset from the Haiti-SIS cruise. The seismic reflection profiles show that the structural and sedimentary architecture of the insular slope varies significantly from central to eastern Cuba. This lateral variability seems mainly influenced by the proximity with the Bahama Banks, which act as a succession of local indenters. The width of the insular slope varies from 5-10km in central Cuba to more than 50km in width towards the east off the Guacanayabo-Nipe tectonic corridor. In this region, the insular slope shows a thick sedimentary cover suggesting a main subsiding regional block related to the middle/late Eocene onset of the Guacanayabo-Nipe tectonic corridor. Contrasting lateral deformation patterns in this region are probably related to the diachronous strike-slip events related to the activity of the Cauto-Nipe fault. The coexistence of folds, transtensive and transpressive structures affecting the sedimentary infill attests that the local stress regimes of this fault have gradually changed. Our study correlates offshore deformation phases recorded in the offshore northeastern coast of Cuba, with major deformation episodes recorded onshore Cuba from Eocene to present-day. Our tectonostratigraphic evolution of the eastern offshore of Cuba provides new constraints to improve the knowledge of the geodynamics of the northern boundary of the Caribbean plate.
Delineating driving mechanisms of Phanerozoic climate: building a habitable Earth
Authors: Merdith Andrew , Mills Benjamin , Maffre Pierre , Goddéris Yves , Donnadieu Yannick , Gernon Thomas
Published: March 2022

The fundamental drivers of Phanerozoic climate change over geological timescales (10–100s of Ma) are well recognised: degassing from the deep-earth puts carbon into the atmosphere, silicate weathering takes carbon from the atmosphere and traps it in carbonate minerals. A number of variables are purported to control or exert influence on these two mechanisms, such as the motion of tectonic plates varying the amount of degassing, the palaeogeogrpahic distribution of continents and oceans, the colonisation of land by plants and preservation of more weatherable material, such as ophiolites. We present a framework, pySCION, that integrates these drivers into a single analysis, connecting solid earth with climate and biogeochemistry. Further, our framework allows us to isolate individual drivers to determine their importance, and how it changes through time. Our model, with all drivers active, successfully reproduces the key aspects and trends of Phanerozoic temperature, to a much greater extent than previous models. We find that no single driver can explain Phanerozoic temperature with any degree of confidence, and that the most important driver varies for each geological period.
Modelling of carbon steel canister and Ca-Mg bentonite boundary development 
Authors: Havlová Václava , Klajmon Martin , Mendoza Angela , Dobrev David , Vokal Antonin
Published: March 2022

The “Assessment of the Chemical Evolution of ILW and HLW Disposal Cells” (abbreviation ACED) Work Package of the EURAD EJP project concerns the assessment of chemical evolution at the disposal cell scale involving component/material interactions and thermal, hydraulic and/or chemical gradients via the consideration of ILW and HLW disposal concepts that are representative of the various approaches being followed in Europe. The general objective of the modelling approach presented here is to create a geochemical and coupled reactive transport model for the assessment of the geochemical evolution along a carbon-steel canister/Ca-Mg bentonite boundary in terms of corrosion rates and geochemical alterations.

The modelling, conducted in the PHREEQC geochemical code, focused on the representation of 3 completed corrosion experiments (temperatures of up to 90°C) that provided data on the corrosion trends of C-steel under compacted Ca-Mg bentonite conditions under both laboratory and in-situ conditions.  

To date, the development of the geochemical modelling in the PHREEQC code includes: 

The modelling of the bentonite pore water chemistry

The equilibrium modelling of the canister - bentonite boundary

The kinetic modelling of corrosion processes at the canister - bentonite boundary

The final step will comprise the development of a complex reactive transport model, including the consideration of Fe migration into the bentonite.

It is planned that the model will also be used for the evaluation of experiments conducted at temperatures of up to 150°C which are currently underway as part of the ConCord WP of the EURAD EJP project.
The influence of Earth’s hypsometry on global sea level through a glacial cycle and into the future
Authors: Pedersen Vivi Kathrine , Gomez Natalya , Pallisgaard-Olesen Gustav , Garbe Julius , Aschwanden Andy , Winkelmann Ricarda , Mitrovica Jerry
Published: March 2022

Earth’s topography and bathymetry is shaped by a complex interplay between solid-Earth processes that deform the Earth from within and the surface processes that modify the outer shape of the Earth. At the surface, an ultimate baselevel set by global sea level marks the defining transition from erosion to deposition. Over geological time scales, this baselevel has resulted in a distinct hypsometric distribution (distribution of surface area with elevation), with the highest concentration of surface area focused in a narrow elevation range near present-day sea level.

This particular feature in Earth’s hypsometry makes the global land fraction very sensitive to changes in sea level. Indeed, a sea-level change will result in a significant change in the land fraction as dictated by the hypsometric distribution, thereby modulating the very same sea-level change. However, it remains unexplored exactly how sea-level changes have modified the global land fraction over past glacial cycles and into the future.

Here we analyse how Earth’s hypsometry has changed over the last glacial cycle as large ice sheets waxed and waned particularly in Scandinavia and North America. These changes in global ice volume resulted in a significant global excursion in sea level, modulated regionally by solid-Earth deformation, gravitational effects, and effects from Earth’s rotation. These changes modified Earth’s hypsometry, and therefore the global land fraction at any given time. Consequently, we can map out how Earth’s hypsometry has influenced global mean sea level (GMSL) over time. To examine this relationship between Earth’s hypsometry and sea level further, we look to the deep future, to a scenario where both the Greenland Ice Sheet and the Antarctic Ice Sheets will melt away completely over multi-millennial timescales. This scenario is not meant to represent a realistic future scenario per se, but it allows us to define the hypsometric GMSL correction needed for any GMSL that the Earth has experienced recently or will experience in the future.
Seismic signals of crater instability at Oldoinyo Lengai volcano, Tanzania
Authors: Rümpker Georg , Kaviani Ayoub , Laizer Amani , Reiss Miriam , Kazimoto Emmanuel
Published: March 2022

Oldoinyo Lengai in the North Tanzanian Divergence is one of the few highly active volcanoes in Africa. Its eruptive cycle is characterized by effusions of carbonatite lava and severe explosions. The most recent of these occurred in 2007 and left a circular crater nearly 400 wide and approximately 100 m deep. The crater is currently being filled with new lava which solidifies and has formed several characteristic hornitos. In 2019, we set up a temporary seismic network of 10 short-period stations, equipped with 4.5 Hz geophones, surrounding the crater area at altitudes between about 1990 and 2885 m to monitor the eruptive activity of the volcano. Seven of the stations were recovered in February 2020. The retrieval of the remaining stations was delayed due travel restrictions caused by the pandemic. However, in Sept. 2021, two of the missing stations were returned from the volcano. Due to the limited battery capacity, recordings were restricted to a period of about five weeks between 14/09 and 23/10/2019. Analysis of the data shows tremor activity and more than 80 distinct recordings of high-frequency seismic signals in the immediate vicinity of the network. However, the recordings lack clear S-wave arrivals, and the station configuration is unfavorable for the application of classical localization techniques based on iterative inversion. We, therefore, apply a grid-search approach based on a Bayesian formulation which also accounts for the topography and shape of the volcanic edifice. The results show that the events are located within or close to the circular crater rim. We argue that the events are caused by sliding segments of the crater wall which have become gravitationally unstable, possibly due to magmatic undermining. The interpretation is supported by surface observations of opening cracks at the outer base of the crater rim.
Are flood protection infrastructures designed according to risk management criteria? 
Authors: D Ayala Margherita , Arosio Marcello , Martina Mario
Published: March 2022

Flooding constitutes the most frequent and one of the most destructive natural disasters, and every year it affects millions of people worldwide causing loss of life, disruption of commerce and financial networks, loss of business continuity and essential services. Even in Italy, floods represent one of the most widespread extreme events, increasingly common and hazardous.

Data from recent Italian reports highlight that the amount of money spent for risk prevention -pre disaster- (330 million per year in average) are not at all comparable to 1.9 billion of euros per year for repair damage and recovery, causing 1:6 ratio between pre- and post-disasters costs.
Hence, the necessity of a deep analysis on the economic and technical criteria used to design infrastructures for flood risk protection. The ReNDiS database (Repertorio Nazionale degli interventi per la Difesa del Suolo – National Database of soil protection measures) offers the data for such an analysis and for a comparison between type of hydraulic infrastructures and the risk maps produced by the District Authority.

 Analysis on the type and costs of hydraulic infrastructures are also performed.  Results show that not always risk management criteria are at the basis of the design of flood protection infrastructures.
The long-term Net Ecosystem Exchange of a remote Siberian high arctic site
Authors: Hensgens Geert , Vonk Jorien , Petrov Roman , Karsanaev Sergey , Maximov Torifm , Dolman Han
Published: March 2022

The arctic is warming at double the average global rate. This raises the concern that permafrost is beginning to thaw and could release large amounts of stored carbon, parts of which can be centuries old. If the total carbon release exceeds the carbon uptake the net ecosystem exchange (NEE) shifts from carbon sink to source, amplifying global warming. Here we present long-term eddy covariance (EC) data of a tundra ecosystem in northeast Siberia, showing the current NEE and its drivers in one of the most remote and coldest EC sites of the northern hemisphere. During the growing season the site is an overall carbon sink. The start of the carbon uptake quickly follows snowmelt and total growing season uptake is positively correlated with an earlier timing of the carbon uptake. While snowfall and the timing of snowmelt is highly variable no discernible trend can be seen in long-term data. In general, increased temperatures yield higher net carbon uptake during the growing season, although this effect levels off at roughly 20°C, likely due to the steadily decreasing solar radiation throughout the growing season. Because of the remoteness and extremely low temperatures, no winter measurements exist. However, machine learning gap filling suggests the site is a small net carbon source during most of the winter. This is in accordance with some of the recent findings at other sites and potentially offsets large parts of the growing season uptake. Thus, while the growing season initially might see increased terrestrial carbon uptake at higher regional temperatures, constraining yearly budgets with winter measurements is indispensable to get a full picture of changes in the total carbon budget of arctic tundra sites in Siberia.
Explainable deep learning for wildfire danger estimation
Authors: Ronco Michele , Prapas Ioannis , Kondylatos Spyros , Papoutsis Ioannis , Camps-Valls Gustau , Fernández-Torres Miguel-Ángel , Piles Guillem Maria , Carvalhais Nuno
Published: March 2022

Deep learning models have been remarkably successful in a number of different fields, yet their application to disaster management is obstructed by the lack of transparency and trust which characterises artificial neural networks. This is particularly relevant in the field of Earth sciences where fitting is only a tiny part of the problem, and process understanding becomes more relevant [1,2]. In this regard, plenty of eXplainable Artificial Intelligence (XAI) algorithms have been proposed in the literature over the past few years [3]. We suggest that combining saliency maps with interpretable approximations, such as LIME, is useful to extract complementary insights and reach robust explanations. We address the problem of wildfire forecasting for which interpreting the model's predictions is of crucial importance to put into action effective mitigation strategies. Daily risk maps have been obtained by training a convolutional LSTM with ten years of data of spatio-temporal features, including weather variables, remote sensing indices and static layers for land characteristics [4]. We show how the usage of XAI allows us to interpret the predicted fire danger, thereby shortening the gap between black-box approaches and disaster management.

 

[1] Deep learning for the Earth Sciences: A comprehensive approach to remote sensing, climate science and geosciences

Gustau Camps-Valls, Devis Tuia, Xiao Xiang Zhu, Markus Reichstein (Editors)

Wiley \& Sons 2021

[2] Deep learning and process understanding for data-driven Earth System Science

Reichstein, M. and Camps-Valls, G. and Stevens, B. and Denzler, J. and Carvalhais, N. and Jung, M. and Prabhat

Nature 566 :195-204, 2019

[3] Explainable AI: Interpreting, Explaining and Visualizing Deep Learning

 Wojciech Samek, Grégoire Montavon, Andrea Vedaldi, Lars Kai Hansen, Klaus-Robert Müller (Editors)

LNCS, volume 11700, Springer 

[4] Deep Learning Methods for Daily Wildfire Danger Forecasting

Ioannis Prapas, Spyros Kondylatos, Ioannis Papoutsis, Gustau Camps-Valls, Michele Ronco, Miguel-Ángel Fernández-Torres, Maria Piles Guillem, Nuno Carvalhais

arXiv: 2111.02736

 
Climate models generally underrepresent the warming by Central Africa biomass-burning aerosols over the Southeast Atlantic.
Authors: Mallet Marc , Nabat Pierre , Johnson Ben , Michou Martine , Haywood Jim , Chen Cheng , Dubovik Оleg
Published: March 2022

Recently, the South-East Atlantic region has been the focus of several field campaigns aimed at understanding the role of aerosols from biomass burning (BBA) in Central Africa between June and September on the radiative budget and climate in the tropics. Contrary to sulphate particles which scatter most of solar radiation, BBA have the particularity of absorbing a large proportion of it. However, these different campaigns, in agreement with recent space observations, have clearly highlighted the highly absorbing nature of these aerosols, which is stronger than previously thought. These optical properties are crucial for understanding the aerosol-radiation-cloud interactions and thus quantify the impact of these plumes on the climate of this region. This study shows that most of the latest generation global climate models that participated in the CMIP6 intercomparison exercise underestimate on average the absorption of solar radiation by BBA transported over the ocean. This bias, combined with recurrent model difficulties in representing marine stratocumulus over this region, leads many models to simulate a negative radiative forcing (cooling) at the top of the atmosphere, which is contrary to recent estimates. The magnitude of the solar warming induced by BBA is thus underestimated by these models, which could lead to an erroneous representation of the fast-response of low clouds and precipitation to the radiative forcing of these aerosols in the tropics.
The influence of structural control in erosion-sedimentation dynamics and morphology of a badland topography 
Authors: Aksay Selçuk , Schoorl Jeroen , Veldkamp Antonie , Demir Tuncer , Aytaç Serdar , Maddy Darrel
Published: March 2022

Development of erosive landscapes leading to Quaternary badland formation (i.e. recognised with highly erodible, poorly consolidated, clay-size sediments and deep gully systems) is commonly associated with various controls such climate change and Anthropocene influence. However, structural control (e.g. in tectonically active areas) plays an essential role in erosional and morphological evolution of badland landscapes as well.

There is a paucity of combining thorough field mapping (e.g. structural mapping) and morphometric analysis (e.g. normalised SL-index calculations) to study the interaction between structural control and Quaternary erosion-sedimentation dynamics in badland landscapes. This multidisciplinary approach, applied in a badland landscape in an extensional tectonic regime in western Turkey, may provide a good understanding to study the influence of structural control on badland development.

Field data analysis supported with the quantitative assessment of longitudinal gully profiles in this study demonstrates that the fault geometry and rock structure play an essential role in net erosion-sedimentation cycles and development of deepened gully networks, influenced by the local adjustments of an asymmetric mini horst-graben system with extension-related faulting. Overall, the development of badlands in our study area is likely to be conditioned by the rock structure and controlled by Quaternary fault activity and its geometry. Further work with age control might provide further insights in understanding the development of this badland topography in future work.
A GEOBIA-based approach for mapping Urban Green Spaces using PlanetScope imagery: the case of Athens
Authors: Dosiadis Evangelos , Triantakonstantis Dimitris , Popa Ana-Maria , Detsikas Spyridon E. , Sandric Ionut , Petropoulos George P. , Onose Diana , Chalkias Christos
Published: March 2022

The technological developments in geoinformatics in recent decades have allowed the inclusion of geospatial data and analysis techniques in a wide range of scientific disciplines. One such field is associated with the study of urban green spaces (UGS). Those are defined as open, undeveloped areas that provide residents with recreational space, improving the aesthetic and environmental quality of the neighboring areas. Mapping accurately their spatial extent is absolutely essential requirement in urban planning and their preservation and expansion in Metropolitan areas are of high importance to protect the environment and public health.

 
The objective of this study is to explore the use of high spatial resolution satellite imagery from PlanetScope combined with the Geographic Object-Based Image Analysis (GEOBIA) classification approach in mapping UGS in Athens, Greece. For the UGS retrieval, an object-based classification (GEOBIA) method was developed utilizing a multispectral PlanetScope imagery acquired in June 2020. Accuracy assessment was performed with a confusion matrix utilizing a set of randomly selected control points within the image selected from field visits and image photo-interpretation. In addition, the obtained UGS were compared versus independent estimates of the Green Urban Areas from the Urban Atlas global operational product. All the geospatial data analysis was conducted in a GIS environment (ArcGIS Pro).

Results demonstrated the usefulness of GEOBIA technique when combined with very high spatial-resolution satellite imagery from PlanetScope in mapping UGS, as was demonstrated by the high accuracy results that were obtained from the statistical comparisons. With the technological evolution in the Earth Observation datasets acquisition and image processing techniques, mapping UGS has been optimized and facilitated and this study contributes in this direction. 

KEYWORDS: Urban Green Spaces, Athens, PlanetScope, Earth Observation, GEOBIA
Past decomposition dynamics in Arctic terrestrial environments revealed by shotgun sedaDNA
Authors: Stoof-Leichsenring Kathleen , Perfumo Amedea , Huang Sichao , Harms Lars , Pestryakova Luidmila , Biskaborn Boris , Herzschuh Ulrike
Published: March 2022

Dynamics of litter decomposition in Arctic terrestrial environments control about carbon storage in permafrost soils and release of CO2 into the atmosphere. Climate warming can accelerate litter decomposition because degradational processes increase, due to shifts in types of labile organic matter available and the composition of decomposing taxa. How litter decomposition changed in former interglacial and glacial periods is rarely studied, because time-series data is lacking, but highly needed to foresee consequences of decomposition and carbon cycling for warming Arctic ecosystems. Innovative shotgun ancient DNA sequencing on sediment core samples provide a snapshot of entire components of past biotic ecosystems and deliver qualitative data on organismal and functional compositional shifts. Our study, for the first time, investigates sedimentary ancient DNA shotgun data in a 52ka sediment core from Far North-Eastern Russia, Lake Ilirney, that recovers former glacial and interglacial periods with pronounced shifts in taxonomic composition in terrestrial vegetation, microbial and fungal diversity. At the same time, the ancient DNA data provides information on gene functions, like degrading enzymes that support variation in functional composition through time. With this data, we aim to understand how litter quality, based on vegetational composition, alters the taxonomic (bacteria, fungi) and functional (enzymes involved in decomposition) community of decomposers. Our result show that glacial times are characterized by tundra vegetation, mainly herbs, accompanied with a dominance of cryophilic soil degraders and relatively lower abundance of enzymes degrading plant organic material. Interglacial periods (like late Holocene) are typified by shrub-tree and heath dominated vegetation with microbes more specialized to degrade plant material, which is supported by an increase of the relative abundance of cellulose and ligninolytic enzymes. Our preliminary results support that under future warming the expansion of shrubs and trees and the increase of specified degraders in Arctic terrestrial environments might lead to enhanced degradation of plant litter resulting in a potential increase of CO2 emissions.
Increasing spatial and temporal resolution in energy system optimization model for energy access – the case of Kenya
Authors: Moksnes Nandi , Howells Mark , Usher Will
Published: March 2022

Energy has been identified as an enabler for several of the Sustainable Development Goals (SDGs). Globally, 759 million people (2019) still lack access to electricity. Energy planning is important to describe the pathway to achieve the nations goals, where energy systems models are important tools to explore scenarios and provide insight. Until recently, modelling energy access with low electrification rate was conducted either at low spatial (e.g. national) or temporal resolution (e.g. annual time slices).  The central grid is often modelled as a black box with approximate optimization methods. This is recognised as unsuitable for understanding integration of technological alternatives to a centralised grid, including distributed generation and mini-grids/renewables. However, methods to model national energy systems at very high spatial and temporal resolutions are data and computation intensive. At the same time increased transparency on the data and code behind these models and insight is important as energy infrastructure is both capital intensive and strategic for the nation.

In this paper we investigate the use of OSeMOSYS, an open-source energy systems model, and increase the spatial resolution while keeping a medium time resolution. OSeMOSYS is a linear programming model and conveniently finds the global optimum in contrast to approximate methods. The approach provides insights into the trade-offs across supply and demand. The model generation is available in an open-source repository where results can be reproduced.

For this paper we use Kenya as our case study where still 16 million people lack access to electricity (2019). We select the spatial resolution to 378 supply cells (40x40km square cells) which leads to 591 demand cells split between electrified and un-electrified. The modelled number of seasons are 12 and the day is split into 3 slices: day, evening, and night, leading to 36 time slices. Specific demand profiles for electrified and un-electrified are assessed in combination with location specific supply options (expansion from the grid, PV, wind, diesel gensets).

Our preliminary results show that the varying un-electrified demand profile, with a high evening peak and low night-time demand, hybrid solutions are preferred with more than one supply option to meet the demand. The expansion of the grid to cells located far away is not motivated due to the low expected consumption, therefore decentralized supply options are required to serve at a high service level.

The results highlight the need for further work to investigate the sensitivity of the spatial and temporal resolutions in combine in energy systems optimization models.
The permeability of loose magma mush
Authors: Bretagne Eloïse , Wadsworth Fabian B. , Vasseur Jérémie , Dingwell Donald B. , Dobson Katherine J. , Humphreys Madeleine C. S. , Rooyakkers Shane
Published: March 2022

Large-volume rhyolitic eruptions are characteristically crystal-poor yet are thought to originate from crystal rich magma mush bodies. This contradiction is explained by the interstitial melt being extracted prior to the eruption, generating large volumes of crystal-poor magmas. The timescale for melt extraction is inversely correlated to the permeability of the mush, defined by the shape of the crystals. Yet, existing approaches for estimating the crystal framework permeability do not account for crystal shape. Here, we represent magma mush by using numerically generated packs of hard cuboids with a range of aspect ratios and at their maximally dense random packing. We use lattice-Boltzmann simulations to constrain the permeability of the cuboid packs, showing that crystal shape exerts a first-order control on both the melt fraction at maximum packing, and on the constitutive relationship between permeability and melt fraction. Using percolation theory and a validation dataset, we develop a predictive scaling framework to compute permeability for mush comprised of crystals that can be approximated by cuboids, valid at melt fractions down to, and including the random maximum packing of crystals. We show that for packs of prolate cuboids, the melt extraction timescale can be reduced by almost two orders of magnitude relative to a pack of oblate cuboids, implying that rejuvenation timescales leading to eruption could be much shorter than previously predicted, using our novel permeability model that is sensitive to crystal shape.
The value of complementary data for physically consistent hydrological models in mountain regions
Authors: Schattan Paul , Winter Benjamin , van der Laan Larissa , Gafurov Abror , Meißl Gertraud , Cuozzo Giovanni , Greifeneder Felix , Premier Valentina , Huttenlau Matthias , Stötter Johann , Förster Kristian
Published: March 2022

In the face of climate change and socio-economic developments, water scarcity is a tremendous challenge. In particular, a significant portion of the world’s population rely on water from cryospheric sources such as snow and/or glacier fed mountain rivers. However, the data coverage in mountain regions is often sparse, which substantially hampers the assessment of climate impacts on hydrological systems. Furthermore, the large impact of climate change on snow and glacier hydrology require physically sound hydrological models.

The gap between the growing need for sustainable water resources management, low data availability and uncertain hydrological projections calls for new approaches. To close this gap, a modular modelling framework was developed to foster the use of complementary data sets in hydrological models. The framework enables a flexible combination of remote sensing and in situ data for model calibration and validation providing a multi-model and multi-input ensemble. The additional consideration of data regarding snow covered area, snow water equivalent and soil moisture allows for physically meaningful representations of key hydrological processes, even in the absence of a dense network of meteorological stations and river discharge gauges.

Case studies in the European Alps (Inn and Adige/Etsch) and in Central Asia (Ala Archa and Karadarya) illustrate the high value of this approach for physically meaningful representations of the hydrological processes. Furthermore, a high impact of glacier retreat on future water availability was found for the highly glacierised basins of the Fagge river in the upper part of the Inn basin and the Ala Archa river.