bluuebunny/crossref_metadata_2025 huggingface dataset:
Designing a Climate Service for Planning Climate Actions in Vulnerable Countries
Authors: Gyllensvärd Frida , Photiadou Christiana , Arheimer Berit , Bosshard Thomas , Capell René , Elenius Maria , Gallo Ilaria , Klehmet Katharina , Little Lorna , Ribeiro Isabel , Santos Léonard , Sjökvist Elin
Published: March 2021

The next generation of climate services needs not only tailoring to specific user needs but also to provide access to key information in a usable way that satisfies the needs of different users’ profiles. This holds especially for web-based services. Here, we present the outcomes from developing such a new interactive prototype, known as Climate Information (https://climateinformation.org/). The service provides data for robust climate analysis to underpin decision-making when planning measures to compensate for climate impact. Readily available climate indicators will help defining future problems, assess climatic stressors, and analyse current and future risks. This makes a climate case, which is the basis for developing interventions and propose investments. The main goal of the platform is to facilitate the communication on climate information between climate modelling communities and adaptation or mitigation initiatives from vulnerable countries that are applying for funds from the Green Climate Fund (GCF).

A participatory process was ensured during four workshops in four pilot countries, organised by the World Meteorological Organisation (WMO), with the active involvement of national and international experts. During this process it was made clear, that there is a strong need for knowledge in climate science in all countries, while in most countries there was also an increasing need of capacity in hydrological modelling and water management.

The active interaction during the workshops was found necessary to facilitate the dialogue between service developers and users. The co-development process is not always institutionalised in many vulnerable countries and the capacity level restricts national entities to only act via international intermediaries. The level of knowledge and capacity in climate and hydrological science in the pilot countries varied significantly, which was an important obstacle when establishing a direct access modality to support different organisations. The diversity of user groups made it difficult to identify a “one-size-fits-all” for the web platform. Instead, a set of interactive tools was developed. Our interactions with the users, which covers a part of a co-development process, facilitated the dialogue between service developers and users. Understanding the users, transparency on potentials and limitations of climate services, and capacity development in climate science and methods were required components in the development of the service.
Automated soil water content-based irrigation under high and low water availability scenarios for a nectarine orchard
Authors: Conesa María R. , Conejero Wenceslao , Vera Juan , Ruiz-Sánchez Mª Carmen
Published: March 2021

In a low water availability scenario, as is increasingly frequent in Mediterranean areas threatened by climate change and endemic water scarcity, to achieve the best irrigation water efficiency is of vital importance. This study aimed to assess the feasibility of an automated irrigation scheduling strategy based on real-time threshold volumetric soil water content values (VSWC), monitored with capacitance probes, in adult early-maturing nectarine orchard (Prunus persica (L.) Batsch cv. `Flariba’, on GxN-15 rootstock). Two drip irrigation practices were tested: one control treatment (T-0) based on conventional crop evapotranspiration calculations (ETc, FAO-56), and one automated treatment (T-A) based on management allowed depletion (MAD) threshold values, derived from VSWC data, with a feed-back control system. Furthermore, for both treatments agro-physiological responses were evaluated under two different water availability scenarios (each one comprised of three consecutive growing seasons): no water restrictions (high water availability), and deficit irrigation (low water availability), in which reduced water to irrigate nectarine trees involved regulated deficit irrigation criteria.  In the high water availability scenario, T-A (MAD = 10%) and T-0 (ETc = 100%) irrigation treatments showed no significant differences in the plant-soil water status, vegetative growth, yield, and nectarine fruit quality parameters. The VSWC was not a limiting factor and full irrigating to achieve a maximum yield was a proﬁtable option. In the low water availability scenario, the T-A treatment (subjected to MAD = 10% during pre-harvest and 30% during post-harvest) received 43% less water than the control, which promoted moderate plant and soil water deficits, leading to a decrease in vegetative growth (winter pruning weight and tree canopy cover), without compromising the total yield and nectarine fruit quality parameters (including an increase in the total soluble solid content). The crop water use efficiency increased by an average of 34%. The proposed automated irrigation strategy, based on MAD seasonal threshold values, combined with regulated deficit irrigation phenological criteria could be considered a promising tool that could be eventually extrapolated to other stone fruit orchards under water scarcity conditions. Acknowledgements: This work was funded by Spanish Agencia Estatal de Investigación (PID2019-106226RB-C21/AEI/10.13039/501100011033) and Fundacion Séneca, Región de Murcia (19903/GERM/15) projects.
Plinian eruptions and their impact on human settlements: stratigraphy of the 79 AD Vesuvius fall deposits and detailed study of their downwind and substrate-induced variations inside the archaeological excavations of Pompeii and Stabiae (southern Italy)
Authors: Chiominto Giulia , Scarpati Claudio , Perrotta Annamaria , Sparice Domenico , Fedele Lorenzo , Santangelo Ileana , Amoretti Valeria , Muscolino Francesco , Rescigno Carlo , Silani Michele , Osanna Massimo
Published: March 2021

Plinian eruptions are highly energetic events that release cubic kilometres of magma in the form of pyroclastic material (pumice, lithic clasts and ash). These products tend to accumulate near the vent with considerable thickness. The rapid burial of the territory around the eruptive centre makes these eruptions extremely dangerous. For this purpose, the renowned 79 AD Vesuvius eruption, which destroyed the ancient cities of Pompeii and Stabiae (where Pliny the Elder founds his death) located respectively 10 and 15 km from the vent, was studied in detailed. The recent excavations carried out in collaboration with the Archaeological Park of Pompeii, both in Pompeii and in the Stabian villas, have shown the complete sequence of products of the 79 AD eruption that destroyed and covered these Roman cities. The discovery of thick sequences of reworked material accumulated during previous excavations, testifies for the presence of underground tunnels dug for the Royal House of Bourbon. Fall products of the 79 AD eruptive sequence, accumulated during the main Plinian phase and the successive sustained column phases, were studied in detail to investigate their sedimentological characteristics and how these were influenced by anthropic structures. Results from field investigation show that in both archaeological sites, fall deposits consist of white and grey pumice lapilli in the lower part of the eruptive sequence (units A and B), and of thin, lithic-rich layers interstratified to ash products emplaced by pyroclastic currents, in the highest part of the pyroclastic deposit (units D, G1, G3, I). A new thin lithic-rich layer (X2) has been observed near the top of the sequence at Stabiae. The internal structure of the Plinian pumice lapilli deposit appears weakly stratified in open areas, while it is strongly stratified near steep roofs (e.g., impluvium areas), where the deposit thickens. The observed stratification is confirmed by a significant variation of sedimentological parameters with the stratigraphic height (e.g., median ranging from -3.5 to -0.1), possibly related to fluctuations in the eruptive parameters. Locally, rolling of pyroclastic clasts on sloped roofs produced a well-stratified deposit with laterally discontinuous layers and rounded clasts. Several roofing-tiles, either intact or in fragments, were recovered at various stratigraphic heights in the pumice lapilli deposit both at Pompeii and Stabiae.  These tiles testify for the progressive collapse of the roofs under the increasing load of the falling lapilli clasts.
The CAP Optimisation Hypothesis Provides Improved Formulations for Stomatal Conductance and Photosynthesis in JSBACH
Authors: Mauranen Aleksanteri , Mäkelä Jarmo , Hölttä Teemu , Salmon Yann , Vesala Timo
Published: March 2021

Stomatal conductance formulations are of great importance to how land surface models predict carbon assimilation and transpiration in vegetation. In this study, novel stomatal conductance formulations based on the CAP optimisation hypothesis (Dewar et al. 2018) are implemented in the land surface model JSBACH. Besides new stomatal conductance functions, the CAP framework enables a computational streamlining of the resolution of photosynthesis rate and leaf internal CO2 concentration.

The formulations are based on the CAP optimisation hypothesis coupled to different photosynthesis models. Models constructed this way incorporate non-stomatal limitations to photosynthesis through the coupling of carbon assimilation to the soil-to-leaf hydraulic pathway. This entails a direct link from soil water status to stomatal conductance, photosynthesis rate and leaf internal CO2 concentration. While this construction does away with the need for some previous fitted or empirical parameters, new parameters are required to represent xylem hydraulic conductance and downregulation of photosynthesis during drought stress.

These new models are compared to the widely used USO stomatal conductance model (Medlyn et al. 2011). A standalone version of JSBACH is run for single grid cells representing two boreal Scots pine (Pinus sylvestris) dominated sites in Finland (Hyytiälä and Sodankylä). Climate forcing is done with FLUXNET data from 2001 through 2012 and observations are from eddy covariance measurements from the two sites.

Preliminary results indicate that some of the new formulations give reasonable results. This is very promising, since they are more detailed and theoretically robust than their semi-empirical predecessors, yet streamline the computational process.

References:
Dewar et al. 2018, New Phytol. 217: 571–581
Medlyn et al. 2011, Glob. Change Biol. 17: 2134–2144
Nature-based solutions for flood mitigation on private land – human rights perspective 
Authors: Bogdzevic Katazyna , Kalinauskas Marius
Published: March 2021

Nature-based solutions (NBS) for flood mitigation lately are becoming more and more popular. However, comparing to traditional grey infrastructure, NBS require more land, often – privately owned. This is why the question of implementation of NBS on private land needs to be addressed more thoroughly. There are different ways how to implement the NBS on private land. Those ways can be divided into "sticks", "carrots" and "sermons". The last two refer to "soft" measures, like financial incentives, payments for ecosystem services, knowledge sharing, and partnership for NBS. Whereas, "sticks" refer to coercive measures, which imply "a command-and-control strategy" and any behaviours contradicting "sticks" can be considered unlawful. In other words, "sticks" are the measures that restrict land-use or even deprive the owners of their land. Expropriation, land-use restrictions, and pre-emption rights are the best-known examples of "sticks". The land-owners have little room for manoeuvre if the state decides to apply "sticks". However, the powers of the state are also limited. One of such limitations derive from international law, to be precise – from provisions related to human rights protection. Article 1 of the Protocol No. 1 to the European Convention on Human Rights grants protection for the property rights and prohibits the authorities to deprive owners of their possession unless the public interest justifies it. The state can also control the use of property only if this is required by general interest. The European Court of Human Rights in its case-law for several times addressed the issue of property restrictions and expropriation due to implementation of environmental laws and land-use planning laws. The Court elaborated on such issues as the notion of "public interest", proportionality and lawfulness of measures adopted by the state. Those considerations can also be relevant for the implementation of NBS on private land. 
High fidelity spectroscopic imaging at low radio frequencies to estimate plasma parameters of solar coronal mass ejections at higher coronal heights
Authors: Kansabanik Devojyoti , Mondal Surajit , Oberoi Divya , Vourlidas Angelos
Published: March 2021

Coronal Mass Ejections (CMEs) are large-scale explosive eruptions of magnetised plasma from the Sun into the Heliosphere. Measuring the physical parameters of CMEs is crucial for understanding their physics and for assessing their geo-effectiveness. Radio observations offer the most direct means for estimating these plasma parameters when gyrosynchrotron (GS) emission is detected from the CME plasma. However, since the first detection by Bastian et al.2001, only a handful of studies have successfully detected GS emission from CME plasma. This is usually attributed to the challenges involved in obtaining the high dynamic range imaging required for observing this faint gyrosynchrotron emission in the vicinity of active solar emissions.

The newly developed imaging pipeline (Mondal et al., 2019) designed for the data from Murchison Widefield Array (MWA) marks a significant improvement in metrewave solar radio imaging. Our work suggests that we should now be able to routinely detect GS emission from CME plasma. We present an example where we have successfully detected radio emission from CME plasma and modelled it as GS emission, leading to reliable estimates of CME magnetic field as well as the distribution of energetic electrons (Mondal et al. 2020). In a different example we are able to detect the radio emission from the CME plasma out to as far as 8.3 solar radii. We find that the observed spectra are not always consistent with simple GS models. This highlights that more complicated physics might be at play and points to the need for building more detailed models for interpreting these emissions. We hope that with the availability of polarimetric imaging capability, which we are in the process of developing, this technique will provide a robust way to routinely measure CME magnetic fields along with its other physical parameters. We note that these are the weakest detections of GS emissions from CME plasma reported yet.
Nonrelativistic electron beam expansion in the solar corona/wind  and their type III radio bursts observed with LOFAR
Authors: Reid Hamish , Kontar Eduard
Published: March 2021

Solar type III radio bursts contain a wealth of information about the dynamics of near-relativistic electron beams in the solar corona and the inner heliosphere; this information is currently unobtainable through other means.  Whilst electron beams expand along their trajectory, the motion of different regions of an electron beam (front, middle, and back) had never been systematically analysed before.  Using LOw Frequency ARray (LOFAR) observations between 30-70 MHz of type III radio bursts, and kinetic simulations of electron beams producing derived type III radio brightness temperatures, we explored the expansion as electrons propagate away from the Sun.  From relatively moderate intensity type III bursts, we found mean electron beam speeds for the front, middle and back of 0.2, 0.17 and 0.15 c, respectively.  Simulations demonstrated that the electron beam energy density, controlled by the initial beam density and energy distribution have a significant effect on the beam speeds, with high energy density beams reaching front and back velocities of 0.7 and 0.35 c, respectively.  Both observations and simulations found that higher inferred velocities correlated with shorter FWHM durations of radio emission at individual frequencies.  Our radial predictions of electron beam speed and expansion can be tested by the upcoming in situ electron beam measurements made by Solar Orbiter and Parker Solar Probe.
The Antilles Current and wind-driven gyre circulation at 26oN
Authors: Frajka-Williams Eleanor , Johns William E. , Bryden Harry L. , Smeed David A. , Duchez Aurelie , Holton Lisa
Published: March 2021

The Antilles Current is a narrow, northward flowing boundary current in the western Atlantic just east of the Bahamas. Its role in the larger scale circulation has been debated: alternately thought to be part of the western boundary closure of the gyre circulation or the northward flowing limb of the meridional overturning circulation (MOC). From 19 years of moored current meter observations (1987--1991, 2004--2018), we define the strength of the Antilles Current by the net transport between the Bahamas and 76.5°W (spanning about 45 km zonally) and in the thermocline (0–1000 m). We find a mean northward transport of 3.5 Sv, substantial interannual variability, and no discernable trend since 1987. The interannual variability of the AC transport is independent of the variability of the Florida Current (the Gulf Stream through the Florida Straits). Instead, the Antilles Current contributes to the interannual variability of the MOC at 26°N, while the trend in the strength of the gyre circulation (defined as the transbasin thermocline transport minus the AC) is responsible for the trend in the MOC. In particular, the 2009/10 slowdown of the MOC resulted from a weaker northward AC transport, rather than an intensified gyre transport. Using the recent 14 years of in situ transport records, we compare the interannual variability of the gyre circulation to that of wind stress curl forcing via a Sverdrup transport calculation, identifying a potential role for wind stress curl (WSC) forcing at 26°N with a ~2 year lag until 2016.  From 2016, the predicted gyre circulation using WSC diverges from the measured gyre strength.
Crustal structure across Himalayan Frontal Thrust (HFT) using high-resolution seismic datasets
Authors: Verma Shashank , Ghosal Dibakar , Vats Viaks , Pandey Shudhanshu , Anand Pratyush , Srivastava Harshad
Published: March 2021

The Himalayan fold-thrust belt has been developing due to the northward convergence of the Indian plate against the Eurasian plate since ~55 Ma. Three major thrust systems: Main Central Thrust (MCT), Main Boundary Thrust (MBT), and Himalayan Frontal Thrust (HFT) are distinctly observed in the Himalayan orogeny from north to south indicating southward propagation of active deformation. These active thrust systems produced several devastating earthquakes in the past such as 1905 Kangra (Mw 7.8), 1934 Nepal-Bihar (Mw 8), and 1950 Assam (Mw 8.6) earthquakes. Presently HFT is found to be the tectonically very active zone that accommodates a strain rate of ~10-15 mm/year and is a zone for great threats in near future to the societies residing over the Himalayan foothills. The present study carried out in the lower Siwalik Himalaya near Pawalgarh in Nainital District of Uttarakhand, India with an objective to estimate the velocity model across HFT in the locality. To accomplish the objective, seismic data were acquired along three profiles of a cumulative length of ~13 km using a seismic thumper as a source and 96 vertical component geophones with the natural frequency of 5 Hz and Remote Acquisition Unites (RAUs) as sensors and data loggers, respectively, and with a group and shot interval of 20 m and near offset of 100 m. Highly uneven Himalayan terrain causes large static errors. In order to overcome this challenge, we used Real Time Kinematics (RTK) to estimate more precise source and receiver surface elevation. In the pre-processing phase of acquired seismic data, three different shots taken at the same location are vertically stacked to eliminate random non-coherent noises and improve the SNR of the data. We then applied a low-frequency array filter (LFAF) to suppress the ground roll using velocity estimates from the ambient noise tomography (ANT). We process the data by implementing conventional seismic processing techniques including normal move-out (NMO) correction, velocity analysis followed by stacking. In the stack section, we observe a northward dipping reflector extending from the surface to ~ 1- 1.25 s TWT indicating evidence of HFT. Another reflector observed at ~3-4 s TWT demarcating the extent of overlying sedimentary deposits on the top of the under-thrusting lithosphere. Rocks of the Siwalik Himalaya mainly composed of sedimentary deposits of sandstone mudstone, and alluvial deposits. Average velocity obtained from the refraction tomography ~ 2900 m/s matches well with rock type in the region. Thus, the high-resolution crustal structure across the highly active HFT can be crucial to understand the earthquake mechanism in the locality and for a better hazard assessment.
Looking for soil structure
Authors: Weller Ulrich
Published: March 2021

Ever since mankind has started to dig up the earth for planting, we are concerned with soil structure. For a long time digging the soil and breaking it into pieces was the only way to get insight into its architecture. Many valuable things were learned by this way: how the stability of the structure depends on the constituents, which soils are accessible for roots. To study the soil constituents in detail and in their natural ensemble has only begun about 90 years ago with the establishment of micromorphology. Thus, describing the soil by looking at its pieces has a 100 times longer history.

The new endeavor started with looking at the solid constituents of soil. The arrangement gave a new insight on processes, and enabled to describe the development of minerals, the activity of soil fauna and the diffusion of substances. It was in a rather descriptive manner that the light of microscope was shed on the soil structure.

With the introduction of X ray CT a new chapter was opened. Now it became possible to generate sufficient data for a quantitative analysis of the soil space. And with that the study of a new aspect of soil structure became feasible: the description of the pore space. Most of the functions of soil architecture are directly related to the pore space, thus a quantitative tool to describe this feature was required to understand the influence of pore space architecture on soil functions. The possibility to quantify pore space has meanwhile gotten a new tool: a standardized quantitative evaluation routine together with a comprehensive and growing library of evaluated soil structure images.

Here we are. We have to go on. To study dynamics of structural development is still tedious and can only be achieved by getting small glimpses at points in time.

New techniques occur. As is X ray CT for pore space, imaging techniques for the composition and arrangement of the solid phase evolve. They will give rise for new quantitative descriptions of soil forming processes.

Yet all this insight has to be digested and put into meaningful concepts. To profit from the wealth of information on pore space dynamics we have to implement models that can deal with a dynamic pore space. For soil hydraulics such a model is in development. It shows a clear dependency of the soil’s properties on the structure. With this, the importance of soil structure forming and preserving in agricultural management can be stressed.

 
Point-to-point ICESat-2 vs CryoSat-2 comparison
Authors: Haacker Jan , Wouters Bert , Slobbe Cornelis
Published: March 2021

For measuring the mass balance of mountain glaciers, the combination of ICESat-2 and CryoSat-2 data holds the potential to improve both spatial and temporal coverage and measurement quality. Both satellite missions are dedicated to measuring the surface elevation in the cryosphere and complement each other. While CryoSat-2 brings a high spatiotemporal coverage, ICESat-2 measures at high accuracy. CryoSat-2 on its own suffers from measurement biases because its radar waves partly penetrate the firn layer and because of the size of its footprint. The laser altimeter ICESat-2, on the other hand, cannot provide the desired spatiotemporal coverage at all locations. By combining the data, we gain surface elevation estimates with a reduced bias (for the CryoSat-2 data) and an improved coverage at the same time. A combined dataset could provide us with better insight into the effects of extreme weather events and the impact of climate change on glacier dynamics on a sub-regional scale and its influence on the inter-seasonal variability. Here, we present insights into the bias of CryoSat-2 data, which we retrieve using different swath processors, with regards to the ATL06 ICESat-2 data. We compare the data point-to-point to study how the surface conditions influence the observed bias for two test regions featuring a complex topography and a high track density.
Projections of future sea level change from a global perspective and with a focus on South Africa
Authors: Allison Lesley , Palmer Matthew , Haigh Ivan
Published: March 2021

In this work we explore projections of future sea level change using methods that build upon those used for the IPCC 5th Assessment Report (AR5) and Special Report on Oceans and Cryosphere in a Changing Climate (SROCC). These methods use a large Monte Carlo simulation to represent the uncertainty across components of sea level change.  The Monte Carlo approach for global mean sea level is extended to local projections for individual tide gauge locations to ensure traceablity to the global mean projections and preserve correlations between terms in the sea level budget.  As part of the WCSSP South Africa programme (which is a collaborative initiative between the Met Office in the UK and the South African Weather Service), we explore the sea level components for locations around the coast of South Africa and examine the physical drivers of local sea level change signals.  For the individual tide gauge locations, the projection uncertainty is larger than it is for the global mean, but several key details emerge and the drivers of these will be discussed.
Variations in the geochemical composition of dolerites of the Sette-Daban event
Authors: Savelev Aleksandr D. , Khudoley Andrei K. , Malyshev Sergey V.
Published: March 2021

Sette-Daban LIP-related event [1] was dated by U-Pb baddeleyite and Sm-Nd isochron methods, but very limited information has been published on the geochemical and isotopic compositions of the associated igneous rocks. This work presents a new dating and the largest geochemical base of samples from the Sette-Daban event.

Mafic sills of the Sette-Daban event are most widespread in the upper part of the Lakhanda Group and lower part of the Uy Group (Maya-Kyllakh zone). Two intrusions were dated by the U-Pb baddeleyite method, yielding ages of 1005 ± 4 Ma - Sakhara river and 974 ± 7 Ma - Allakh-Yun river [2]. Isotope dating of a sublatitudinal dike in the Belaya River area gave an age which overlaps the already known dating along the Sakhara river.

Studied samples from the rivers Yudoma and Allah-Yun confirmed the already obtained result from the previous work [3]. The Sette-Daban dolerite sills resemble low-Ti lavas of intraplate flood basalt provinces (e.g., Karoo, Siberian Traps) and possess IAB-like trace element patterns.

In turn, samples from the Belaya River are enriched more strongly and closer to the OIB distribution. The rare earth elements contents (e.g., La, Ce, Pr, Nd, Sm) in Belaya samples is 2-5 times higher than in Yudoma. However, εNd(T) values vary from 4.3 to 6.3 which corresponds to the already known range of values for the Sette-Daban complex.

Thus, detailed geochemical studies made it possible to identify a new zone (Belaya) in the Sette-Daban complex, which has significant differences from the previously obtained values.

The studies were supported by the Russian Science Foundation grant No. 19-77-10048.

 

References:

[1] Ernst, R.E. Large Igneous Provinces. In Large Igneous Provinces; Ernst, R.E., Ed.; Cambridge University Press: Cambridge, UK, 2014; p. 653. ISBN 9780521871778.

[2] Rainbird, R.H.; Stern, R.A.; Khudoley, A.K.; Kropachev, A.P.; Heaman, L.M.; Sukhorukov, V.I. U-Pb geochronology of Riphean sandstone and gabbro from southeast Siberia and its bearing on the Laurentia-Siberia connection. Earth Planet. Sci. Lett. 1998, 164, 409–420.

[3] Savelev, A.D.; Malyshev, S.V.; Savatenkov, V.M.; Ignatov, D.D.; Kuzkina, A.D. Meso-Neoproterozoic Mafic Sills along the South-Eastern margin of the Siberian Craton, SE Yakutia: Petrogenesis, Tectonic and Geochemical features. Minerals 2020, 10, 805.
Estimation of Water Content in Vera Rubin Ridge and Glen Torridon areas Based on Measurements of the MSL/DAN Instrument in Gale crater
Authors: Nikiforov Sergei , Djachkova Maya , Mitrofanov Igor , Litvak Maxim , Lisov Denis , Sanin Anton
Published: March 2021

This work presents the latest results on the estimations of Water Equivalent Hydrogen (WEH) gathered in martian areas Vera Rubin ridge (VRR) and Glen Torridon (GT) by the Dynamic Albedo of Neutron (DAN) instrument installed onboard NASA’s Curiosity rover. The main science objective of DAN is to study bound water content in shallow layer of martian subsurface down to 0.6 m [1].

Extensive scientific campaign on Vera Rubin ridge was started in the middle of 2017 and lasted until the beginning of 2019 when the rover reached another region – Glen Torridon. VRR is mostly related to hematite minerals that might be formed in the presence of liquid water. On the other hand, GT region is thought to be associated with clay minerals, according to CRISM observations [2].

We will present the latest results on DAN passive observations in these Mars areas. Data are referred to the period of more than 3 years of observations or MSL traverse segment from 17 km to 23 km. The main result is the notable increase of WEH in GT in comparison with VRR, as well as in comparison with the whole Curiosity traverse. Possibly, the increase may indicate on the qualitative difference in neutron-absorption elements that are forming the soil of the GT region.

References:

[1] Mitrofanov, I. G., et al., (2014). Water and chlorine content in the Martian soil along the first 1900 m of the Curiosity rover traverse as estimated by the DAN instrument. J. Geophys. Res., 119(7), 1579–1596. doi:10.1002/2013JE004553.

[2] Murchie, S. L., et al. (2009), Compact Reconnaissance Imaging Spectrometer for Mars investigation and data set from the Mars Reconnaissance Orbiter's primary science phase, J. Geophys. Res., 114, E00D07, doi:10.1029/2009JE003344.
Explosive interaction of gravity-capillary triads as the initial stage of “bag-breakup” droplet generation mechanism at high winds 
Authors: Kozlov Dmitry , Troitskaya Yuliya
Published: March 2021

The present work is a theoretical study of the hydrodynamic instability of the water-air interface, the development of which may result in the “bag breakup” fragmentation. This phenomenon begins with the appearance of a small-scale elevation of the water surface, which increases and turns into a small liquid “sail” or “bag”, limited by a thicker rim, and finally bursts into splashes. According to the results of laboratory experiments [1]–[3], the “bag breakup” fragmentation is the most effective droplet generation mechanism at hurricane wind speeds.

We propose a hypothesis that the formation of the initial elevations of the water surface, which undergoes fragmentation, is caused by the hydrodynamic instability of disturbances of the wind drift current in the water. A weakly nonlinear stage of instability in the form of a resonant three-wave interaction has been studied. It has been discovered that the nonlinear resonant interaction of a triad of wind drift perturbations, of which one wave is directed along the flow, and the other two are directed at an angle to the flow, leads to an explosive increase of amplitudes as it was in [4]. Within the framework of the piecewise-continuous model of the drift current profile, the characteristic time and spatial scales of disturbances have been found and it has been shown that their characteristic dependences on the air friction velocity are consistent with the previously obtained experimental data.

Acknowledgements

This work was supported by RFBR projects (19-35-90053, 19-05-00249) and the Foundation for the Advancement of Theoretical Physics and Mathematics “BASIS”.

 
Trends in spectrally resolved OLR from 10 years of IASI measurements
Authors: Whitburn Simon , Clarisse Lieven , Delcloo Andy , Dewitte Steven , Bouillon Marie , George Maya , Safieddine Sarah , Coheur Pierre , Clerbaux Cathy
Published: March 2021

The Earth's Outgoing Longwave Radiation (OLR) is a key component in the study of climate. As part of the Earth's radiation budget, it reflects how the Earth-atmosphere system compensates the incoming solar radiation at the top of the atmosphere. At equilibrium, the two quantities compensate each other on average. Any variation of the climate drivers (e.g. greenhouse gases) causes an energy imbalance which leads to a climate response (e.g. surface temperature increase), with the effect of bringing the radiation budget back to equilibrium. Considerable improvements in our understanding of the Earth-atmosphere system and of its long-term changes have been achieved in the last four decades through the exploitation of measurements from dedicated broadband instruments. However, such instruments only provide spectrally integrated OLR over a broad spectral range and are therefore not well suited for tracking separately the impact of the different parameters affecting the OLR.

Better constraints can, in principle, be obtained from spectrally resolved OLR (i.e. the integrand of broadband OLR, in units of W m-2 cm-1) derived from infrared hyperspectral sounders. Recently, a dedicated algorithm was developed to derive clear-sky spectrally resolved OLR from the Infrared Atmospheric Sounding Interferometer (IASI) at the 0.25 cm-1 native spectral sampling of the L1C spectra (Whitburn et al. 2020).  Here, we analyze the changes in 10 years (2008-2017) of the IASI-derived OLR and we relate them to known changes in greenhouse gases concentrations (CO2, CH4, H2O, …) and climate phenomena activity such as El Niño-Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO).

Whitburn, S., Clarisse, L., Bauduin, S., George, M., Hurtmans, D., Safieddine, S., Coheur, P. F., and Clerbaux, C. (2020). Spectrally Resolved Fuxes from IASI Data: Retrieval algorithm for Clear-Sky Measurements. Journal of Climate. doi: 10.1175/jcli-d-19-0523.1
Investigating how platform height affects sea ice radar returns with KuKaSim
Authors: Newman Thomas , Willatt Rosemary , Stroeve Julienne , Mallet Robbie , Tsamados Michel , Nandan Vishnu
Published: March 2021

Current, and ongoing observations, of Arctic sea ice, indicate a trend towards a younger, thinner and more mobile pack that exhibits significant inter-annual variability. Satellite and airborne radar altimeters have been used extensively to quantify these changes by deriving sea ice freeboard to infer sea ice thickness. Radar returns from altimeters are impacted by both the morphology of snow and ice features on the sea ice surface, in addition to the radar properties of the snowpack, with both contributing to uncertainties in radar-derived sea ice freeboard. Here we make use of airborne lidar data, collected as part of the MOSAiC expedition in the winter of 2019/2020, to investigate the effect of sea ice surface morphology on radar altimeter measurements. We quantify these effects using 'KuKaSim' a forward-modelling approach based on the KuKa instrument deployed at MOSAiC, which allows us to investigate how simulated radar returns vary with radar height. Our results allow us to better constrain the altimetric uncertainty resulting from ice surface morphology, with respect to both radar height and sea ice type, leading to an enhanced understanding of sources of uncertainty in altimeter-derived sea ice thickness products.
Integrating institutions into a socio-hydrological model: an example for water quality management in Burkina Faso
Authors: Carr Gemma , Barendrecht Marlies , Debevec Liza , Balana Bedru
Published: March 2021

The variety of demands that people place on water resources, coupled with the dynamics of the natural system, make water resource management highly complex. Models that can integrate aspects of society such as institutions, perceptions and behaviors along with aspects of the natural system such as rainfall, runoff and water quality could offer a realistic approach to better understand and manage these complex systems. Much research progress in the development of such socio-hydrological models has been achieved in recent years. However, many gaps exist on how the decisions and actions of institutions and agencies, and their subsequent impacts on individuals, can be integrated within such models. In this study, a socio-hydrological model was developed using a set of empirical field data from the Black Volta (Mouhoun) watershed in south west Burkina Faso. Cultivation of the riparian zones and use of agrochemicals are commonly associated with increased sedimentation in the river and water pollution, respectively. The model aims to capture the relationships between agency support for water quality management, the capacity of local organizations to support farmers and land users, land use changes in the riparian zones, improved agricultural practices employed by farmers (e.g., reduced tillage, organic farming, or cultivating tree crops rather than vegetables), and suspended sediment concentration in the river as an indicator of water quality. The model is set up to reflect the current situation and scenarios are generated depicting plausible pathways to achieve improved water quality through riparian land management strategies. Comparison of the modelled scenarios shows that water quality could be improved if institutional support and public resource allocation for water management is raised, and the capacity of local level organizations is substantially increased compared to current levels. Semi-quantitative socio-hydrological models, such as the one developed in this study, may provide insights for the comparison and prioritization of different management strategies and guide interventions or support mechanisms that enable riparian land users to change their agricultural practices and lead to water quality improvements.
Higher Education engagement in citizen enhanced open science: Between Humanities and Natural Sciences
Authors: Zourou Katerina , Ziku Mariana
Published: March 2021

The importance of HEIs in supporting and promoting open science is highlighted in several EU policies. Among them, the 2017 Report of the Working Group on Education and Skills under Open Science emphasizes the need to shape HE students/next generation researchers as “open science citizens”. More precisely: “The European Research Area (ERA) should work in closer collaboration with the European Higher Education Area (EHEA) (...), enabling the next generations of researchers to evolve as Open Science citizens (...) New generations of scientists and researchers, as the driving force for innovation and economic growth, are of vital importance to Europe's future competitiveness and leadership” (p. 16).

Our study problematizes on the role of HEIs as incubators of the next generation open science citizens (in terms of HE staff and student skills, curricula and interdisciplinarity), including a niche of cross-disciplinary humanities and natural sciences applied cases, where institutions situated in a broader social context leverage citizens in knowledge creation processes through professional-amateur (pro-am) collaborations, and in decision making in diverse populations as urban, Indigenous or special needs communities (active citizenship, civic engagement, citizen science). 

The study, initiated by the European project CitizenHeritage ("Citizen Science Practices in Cultural Heritage: towards a Sustainable Model in Higher Education", https://www.citizenheritage.eu/ ) presents the analysis resulting from a desktop research and a survey on practices conducted between November 2020 and January 2021. The presentation focuses on a number of registered practices that bridge scientific disciplines in the areas of earth and life sciences, history of science and cultural heritage, producing a substantial, evidence-based review of multimethod research practices of Higher Education engagement in citizen enhanced open science.
Aerosol classification using sun photometer and lidar data within a machine learning algorithm-a possible nowcasting application
Authors: Buxmann Joelle , Osborne Martin , Protts Mike , O'Sullivan Debbie
Published: March 2021

The Met Office operates a ground based operational network of nine polarisation Raman lidars (aerosol profiling instruments) and sun photometers (column integrated information). An aerosol classification scheme using supervised machine learning has been developed. The concept of Mahalanobis (~normalized) distance to identify the aerosol type  from individual Aerosol Robotic Network (AERONET) measurements including Extinction Angstrom Exponent, Absorption Angstrom Exponent, Single Scattering Albedo and Index of refraction is used for a subset of AERONET stations around the globe of known main aerosol types (training set). The aerosol types  include maritime, urban industrial, biomass burning and dust. We build a predictive model from this training set using K nearest neighbour machine learning algorithms. The relation of particle polarisation ratio and lidar ratio from the Raman lidar is used as a sanity check.  We apply the model to 3- 4 years of AERONET and profiling data across the UK, with instruments evenly distributed across the country, from Camborne in Cornwall to Lerwick in the Shetland Islands. We are showing more detailed data of a dust event in May 2016, dust/biomass burning aerosol mix from October 2017 (hurricane Ophelia) and more recent aerosol transported from the Canadian wild fires in September 2020. AERONET Level 2.0  data is compared to level 1.5 in order to determine the implications for the aerosol classification. Level 1.5 data are cloud-screened, but not quality assured and may not have the final calibration applied. Level 2.0  data have pre- and post-field calibration applied, are cloud-screened, and quality-assured data. As level 2.0 data is usually only available after 1-2 years (after a new calibration has been performed), it is important to understand the  usefulness of more readily available level 1.5 (cloud screened) data.

The aim is to build a real time aerosol classification application that can be used in Nowcasting.
Assessing the impact of rainfall intensification on ecosystem productivity
Authors: Moustakis Yiannis , Fatichi Simone , Onof Christian J , Paschalis Athanasios
Published: March 2021

Increasing atmospheric CO2 levels, temperature, and atmospheric drought as well as changes in rainfall structure (event frequency, storm intensity) are expected to jointly alter ecosystem responses in the future. High-resolution convection-permitting models have been recently employed at continental scales to develop robust projections of climate, and particularly precipitation, at fine spatiotemporal scales (~1km, ~1hour) overcoming the documented limitations of larger scale general circulation models.

Climate projections at fine spatiotemporal scale can support robust quantification of ecosystem responses under a changing climate when used in conjunction with state-of-the-art terrestrial biosphere models resolving the soil – vegetation – atmosphere continuum processes at those scales. In this study, we assess the changes in ecosystem functioning for multiple biomes in North America. We use the 4km, 1-h future WRF continental-wide simulation over the US together with a state-of-the-art stochastic weather generator and the Tethys & Chloris ecohydrological model to investigate ecosystem responses for 33 sites where eddy covariance data exist (i.e., FLUXNET sites).

We designed a series of numerical experiments tuned to disentangle the roles of CO2, temperature and the structure of precipitation, while considering the effect of natural weather variability.

Our results reveal that the impact of mean annual rainfall is dominant in more arid sites, while sites of intermediate wetness are more sensitive to the temporal structure of precipitation at fine scales. Wet sites, which are energy limited, are more sensitive to temperature increase instead. The impact of rainfall is partly offset by increases in atmospheric drought. The fertilization effect of elevated CO2 levels is strong in this high-end (RCP 8.5) scenario across all sites. Fertilization is more pronounced for sites of low and intermediate wetness, where stomatal closure allows for positive feedbacks through water savings.
A high resolution reanalysis for the Mediterranean Sea
Authors: Escudier Romain , Clementi Emanuela , Omar Mohamed , Cipollone Andrea , Pistoia Jenny , Drudi Massimiliano , Grandi Alessandro , Lecci Rita , Aydogdu Ali , Masina Simona , Coppini Giovanni , Pinardi Nadia
Published: March 2021

In order to be able to predict the future ocean climate and weather, it is crucial to understand what happened in the past and the mechanisms responsible for the ocean variability. This is particularly true in a complex area such as the Mediterranean Sea with diverse dynamics such as deep convection and thermohaline circulation or coastal hydrodynamics. To this end, effective tools are reanalyses or reconstructions of the past ocean state. 

Here we present a new physical reanalysis of the Mediterranean Sea at high resolution, developed in the Copernicus Marine Environment Monitoring Service (CMEMS) framework. The hydrodynamic model is based on the Nucleus for European Modelling of the Ocean (NEMO) combined with a variational data assimilation scheme (OceanVar).

The model has a horizontal resolution of 1/24° and 141 vertical z* levels and provides daily and monthly 3D values of temperature, salinity, sea level and currents. Hourly ECMWF ERA-5 atmospheric fields force the model and daily boundary conditions in the Atlantic are taken from the global CMCC C-GLORS reanalysis. 39 rivers model the freshwater input to the basin plus the Dardanelles. The reanalysis covers 33-years, initialized from SeaDataNet climatology in January 1985, getting to a nominal state after a two-years spin-up and ending in 2019. In-situ data from CTD, ARGO floats and XBT are assimilated into the model in combination with satellite altimetry data.

This reanalysis has been validated and assessed through comparison to in-situ and satellite observations as well as literature climatologies. The results show an overall improvement of the skill and a better representation of the main dynamics of the region compared to the previous, lower resolution (1/16°) reanalysis. Temperature and salinity RMSE is decreased by respectively 12% and 20%. The deeper biases in salinity of the previous version are corrected and the new reanalysis present a better representation of the deep convection in the Gulf of Lion. Climate signals show continuous increase of the temperature due to climate change but also in salinity.

The new reanalysis will allow the study of physical processes at multi-scales, from the large scale to the transient small mesoscale structures.