bluuebunny/crossref_metadata_2025 huggingface dataset:
Quaternary Environmental Changes in the Corinth Rift Area: the IODP 381 Palynological Record
Authors: Fatourou Eugenia , Kafetzidou Aikaterini , Panagiotopoulos Konstantinos , Marret Fabienne , Papadopoulou Sofia , Kouli Katerina , 381 Science Team the Expedition
Published: March 2021

The new sedimentary record from the Gulf of Corinth (south Greece), retrieved within the IODP Exp. 381: Corinth Active Rift Development, is a new archive registering environmental and climatic variability continuously over the last one million years. The Gulf of Corinth, strategically located at the southernmost tip of the Balkan Peninsula, is a semi-enclosed basin that is sensitive to climate forcing and sea level fluctuations. The Gulf was repeatedly isolated from the Mediterranean Sea during glacial/low-stand intervals, resulting in the amplification of paleoenvironmental gradients (McNeill et al., 2019).

The “Quaternary Environmental Changes in the Corinth Rift Area: the IODP 381 palaeovegetation record (QECCoRA)” project aims to analyse how climate variability affected the development of local vegetation and marine ecosystems in response to glacial/interglacial cycles, using palynological analysis (terrestrial and aquatic palynomorphs). The main goals are: a) to study the glacial-interglacial vegetation history in the southernmost Balkan tree refugium at a millennial scale b) to constrain the timing of Quaternary extinctions of relict tree taxa, and c) to decipher the alternation between marine and isolated intervals and its impact on aquatic ecosystems and the depositional environment using the aquatic palynomorph record.

The first results of the microscopic analysis show significant shifts of the vegetation composition in response to climate variability, nevertheless the fluctuation in vegetation cover appears less pronounced. Dinoflagellate cysts show distinct alternations between marine and brackish conditions revealing changes in surface water salinity, productivity, and temperature. Ongoing palynological analysis will produce a skeleton paleoenvironmental record that will contribute to further analyses carried out within the IODP Exp. 381 Science team.

 

The QECCoRA project is supported by the Hellenic Foundation of Research and Innovation (H.F.R.I., Project Number: 1026)

 

Reference

McNeill LC, Shillington DJ, Carter GDO, Everest J, Gawthorpe R, Miller C, Phillips M, Collier R, Cvetkoska A, De Gelder G, Diz Ferreiro P, Doan M-L, Ford M, Geraga M, Gillespie J, Hemelsdael R, Herrero-Bervera E, Ismaiel M, Janikian L, Kouli K, Le Ber E, Li S, Maffione M, Mahoney C, Machlus M, Michas G, Nixon C, Oflaz SA, Omale A, Panagiotopoulos K, Pechlivanidou S, Sauer S, Seguin J, Sergiou S, Zhakarova N, Green S, High-resolution record reveals climate-driven environmental and sedimentary changes in an active rift, Scientific Reports, 9:3116, 2019, https://doi.org/10.1038/s41598-019-40022-w
Analysis of Long-term Variability through Temperature and Humidity Data in Urban Meteorological Observation Network
Authors: kang Eun-Bi , Kang Deok-Du , Lee Dong-In
Published: March 2021

In the process of producing grid data using observation data, the density of the stations were found to have the greatest influence on spatial (Hwang and Ham, 2013). Currently, the resolution of Korea’s ground detection network is about 12 to 15km additional stations need to be set up to improve spatial accuracy. However, indiscriminate installation of observatories is an objective challenge because of the enormous cost and the various factors to consider. It is important to select major observation points on an objective basis based on the existing KMA (Korea Meteorological Administration)'s AWS(Automatic Weather System), ASOS(Automated Synoptic Observing System)  data to increase the representative and reliability of the observation data. However, the establishment of an observatory so far has been chosen for subjective observation purposes, which may make it difficult to derive scientific data. In this study there is identified the long-term variability of urban meteorological data using the Hurst exponent (H) obtained through Rescaled range analysis (R/S analysis). And additional observation points are proposed for each meteorological element through network analysis.

R/S analysis is an analysis that measures the variability of time series by standardizing observations over time to make them in a dimensionless ratio and analyze the changes according to the length of the data used. H between 0 and 1 provides a criterion for distinguishing the measure of correlation that a time series has. H = 0.5 means that the present event does not affect subsequently, however the other values are correlated, not independent, and continuum of influence (Hwang and Cha 2004). The meteorological factors data were obtained from SK planet, AWS, ASOS installed in Seoul. As a result, long-term relativity between temperature and humidity are shown to be at a minimum of 0.750 and a maximum of 0.941.

Key words :  R/S analysis, Hurst exponent, long-term relativity
ADRON instrument for future missions to Moon and Mars: active neutron and gamma-ray spectroscopy
Authors: Mokrousov Maxim , Golovin Dmitriy , Mitrofanov Igor , Kozyrev Alexander , Litvak Maxim , Malakhov Alexey , Sanin Anton , Tretyakov Vladislav , Anikin Artem
Published: March 2021

The series of ADRON instruments are developed in Russian Space Research Institute (IKI) for Russian Luna-25, Luna-27 and Roscosmos-ESA ExoMars-2022 landers. The main goal of this experiment is studying of elemental composition of planetary sub-surface down to 1 m. Using pulsing neutron generator and observing albedo after-pulse neutron and gamma-ray emission from the soil, one can detect layering stratification of hydrogen and mass fractions of other elements.

Both instruments consist of two blocks: pulsing neutron generator (PNG) with 14 MeV neutron pulse duration around 1 microsecond, and detector block with neutrons and gamma-ray detectors based on 3He counters and CeBr3 (LaBr3) scintillator, respectively. 3He counters allow to detect thermal and epithermal neutrons, which are the most sensitive to hydrogen in underlying soil, and gamma-ray detector allows to detect nuclear lines at the energy range from 200 keV up to 10 MeV. Readout and digital electronics is designed to minimize the dead-time of signal processing. It allows to accumulate the after-pulse profiles of emission of neutrons and gamma-rays with very good time (from 2 microsecond) and spectral resolutions (about 4 % for 662 keV).

The results of laboratory measurements and numerical simulations for ADRON units will be presented for post-pulse emission of neutrons and gamma rays from the planetary soil with different water content, elementary composition and layering structure.

 
Tracing Martian volcanic activity using crater obliteration rate
Authors: Breton Sylvain , Pan Lu , Quantin-Nataf Cathy , Brustel Clément , Flahaut Jessica
Published: March 2021

Impact craters are often used to date planetary surfaces, the density of crater increasing with the exposure age of the surface. However, some geologic event, such as lava flows, do not totally “reset” the crater clock. Indeed, larger craters, rather than being totally recovered by the lava flow will be only partially filled.

In that case, the crater size frequency distribution differs from cratering models. In order to better describe crater populations, additional parameters can be included. To this purpose we build crater size and depth frequency distributions that offers a snapshot of the current degradation state of the population.

We used cratering models to interpret crater size and depth frequency distributions in terms of crater infilling rates. Using both global crater database and more local high resolution crater maps, we estimated crater obliteration rates on various Martian volcanic provinces.

Our method proven efficient to track activity of the main Martian volcanic provinces. Resurfacing rates reach several thousands of m/Gy. Pic activity differs from provinces. Syrtis and Hesperia are the oldest with the highest and oldest observed rates around 3.7 Gy. The activity of those provinces quickly decreases reaching few hundreds of m/Gy around 3.4 Gy. During Hesperian, Tharsis is the most active surface of Mars with high resurfacing until 3.3 Gy. Finally, our result shows an increase of resurfacing, reaching few hundreds of m/Gy in Amazonis planitia from 2 Gy to present.
Evaluating Simplified Numerical Models of Debris-Covered Glaciers
Authors: Ferguson James C. , Bolch Tobias , Vieli Andreas
Published: March 2021

The transient response of debris-covered glaciers to a changing climate is governed by nonlinear feedbacks between ice dynamics, debris transport, and glacier geometry and that act over a wide range of temporal and spatial scales. Current numerical models that are able to accurately represent the relevant physical processes are computationally expensive since they must track the debris transport not only at the glacier surface but also englacially. This makes such models difficult to use for simulations at the regional to global scale.

In order to address this challenge, we developed a fully coupled numerical model that solves both englacial debris transport and ice flow and includes the effect of debris cover on surface ablation. We use this model to evaluate different simplified approaches to modelling debris-covered glaciers. These simplifications include parametrized 1-D debris transport models, parametrized models of surface mass balance that include debris cover effects, and zero-dimensional models. We compare the model performances using a number of tests with an idealized synthetic glacier geometry and a range of forcings, thereby allowing for an evaluation of the relative merits of each approach. A key goal of this work is to provide guidance and tools for modelling studies involving debris cover at the regional to global scale.
Interrelationships among mass balance, meteorology, discharge, and surface velocity on Chhota Shigri Glacier over 2002-2019 using in-situ measurements
Authors: Alagappan(AL) Ramanathan , Mandal Arindan , Mohd Azam Farooq , Angchuk Thupstan , Mohd Soheb , Kumar Naveen , Pottakkal Jose George , Vatsal Sarvagya , Mishra Somdutta , singh Virendra Bhadur
Published: March 2021

Interrelationships among mass balance, meteorology, discharge, and surface velocity on Chhota Shigri Glacier over 2002-2019 using in-situ measurements

 

 

Arindan MANDAL1, AL. RAMANATHAN1*, Mohd. Farooq AZAM2, Thupstan ANGCHUK1, Mohd. SOHEB1, Naveen KUMAR1, Jose George POTTAKKAL3, Sarvagya VATSAL1, Somdutta MISHRA1, Virendra Bahadur SINGH1,4

 

*Corresponding author email: alrjnu@gmail.com

The Himalayan glaciers contribute significantly to regional water resources. However, limited field observations restrict our understanding of glacier dynamics and behavior. Here, we investigated the long-term in-situ mass balance, meteorology, ice velocity, and discharge of the Chhota Shigri Glacier over the past two decades. With 17 years of uninterrupted glacier-wide mass balance datasets, Chhota Shigri Glacier is one of the most studied glaciers in the Hindu-Kush Himalayan region in terms of mass balance record. The mean annual glacier-wide mass balance was negative, -0.46±0.40 m w.e. a-1 during 2002-2019 corresponding to a cumulative wastage of about -8 m w.e. Mean winter mass balance was 1.15 m w.e. a-1 and summer mass balance was -1.35 m w.e. a-1 over 2009-2019. Surface ice velocity has decreased on average by 25-42% in the lower and middle ablation zone (below 4700 m a.s.l.) since 2003; however, no substantial change was observed at higher altitudes. The decrease in velocity suggests that the glacier is adjusting its flow in response to negative mass balance. The summer discharge begins to rise from May and peaks in July, with a contribution of 43%, followed by 38% and 19% in August and September, respectively. The discharge pattern closely follows the air temperature. The long-term observation on the Chhota Shigri — a benchmark — glacier, shows a mass wastage that corresponds to the glacier’s slowdown in the past two decades.

 

 
Geochemical peat records from the Great Vasyugan Mire and Tomsk region, Siberia. Regional temporal trend of human impact over the last 500 years and local perturbations.
Authors: Hutchinson Simon , Diaconu Andrei , Kirpotin Sergey , Feurdean Angelica
Published: March 2021

Although interest in peatland environments, especially in terms of their carbon storage, has gained momentum in response to a heightened awareness of the climate emergency; significant gaps remain in the geographical coverage of our knowledge of mires, including some major wetland systems. This paucity has implications, not only for our understanding of their development and functioning, but also for adequately predicting future changes and thus providing effective mire environmental management. Our INTERACT-supported study provides radiometrically dated, well-characterised millennial scale peat records from two contrasting undisturbed and impacted (ditched) ombrotrophic sites in the Great Vasyugan Mire (GVM) near Tomsk, Siberia and two additional mesotrophic sites to the east of the Ob river. In addition, the geochemical record was complemented by multiproxy palaeoecological characterisation (pollen, charcoal, stable isotopes, testate amoeba). We identified both natural (lithogenic) and anthropogenic geochemical signals recording human impacts with site specific variations. Elevated trace element concentrations in the peat profiles align with the region’s wider agricultural and economic development following the colonisation of Siberia by Russia (from ca. 1600 AD) when pollen assemblages indicate the decline of forest cover and an increase in human disturbance, including the use for fire. Trace element concentrations peak with the subsequent, post WWII industrialisation of regional centres in southern Siberia (after 1950 AD). On a global scale, our sites, together with evidence from the few other comparable studies in the region, suggest that the region’s peatlands are relatively uncontaminated by human activities with a mean lead (Pb) level of < 5 mg/kg. However, via lithogenic elements including Rb, Ti and Zr, we detected both a geochemical signal as a result of historical land cover changes enhancing mineral dust deposition following disturbance, as well as fossil fuel derived pollutants as relatively elevated, subsurface As and Pb concentrations of ca. 10 and 25 mg/kg respectively with the development of industry in the region. Nevertheless, the potential significance of local factors on the sites’ geochemical profile is also highlighted. For example, we identify the effects of past peat drainage for afforestation (ca. 1960s) and the scheme’s subsequent abandonment. Although the region’s mire systems are remote and vast, they appear to hold a legacy of human activity that can be detected as a geochemical signal supporting the inferences of other palaeoenvironmental proxies. Such geochemical peat core records, from Eurasia in particular, remain relatively scarce in the international scientific literature and therefore, as yet, inadequately characterised and quantified compared to other regions.
Geophysical patterns in tropical tropospheric ozone by TROPOMI, OMI, GOME-2B and ozonesonde
Authors: Hubert Daan , Heue Klaus-Peter , Lambert Jean-Christopher , Verhoelst Tijl , Keppens Arno , Compernolle Steven , Dehn Angelika , Kollonige Debra E. , Lerot Christophe , Loyola Diego , Romahn Fabian , Thompson Anne M. , Veefkind Pepijn , Zehner Claus ,   SHADOZ ozonesonde station PIs and staff
Published: March 2021

Ecosystems and human health are severely harmed by elevated concentrations of tropospheric ozone, in the short and the long term. Monitoring ozone at all relevant spatial and temporal scales simultaneously is a challenge for a global observing system due to the large variability of ozone levels in the troposphere. Space-based sensors provide near-global coverage at the synoptic scale, but their accuracy is limited since the large stratospheric O3 column shields the view on the relatively small tropospheric ozone concentrations. In contrast, in-situ soundings by balloons are sparse, but these are more accurate and at a high vertical resolution. As a result, the geophysical information that can be inferred from tropospheric ozone data records differs.

We present a comprehensive comparison of the spatial and temporal patterns in tropical tropospheric ozone column observations by nadir-viewing satellite sensors (Sentinel-5 Precursor/TROPOMI, EOS-Aura/OMI and Metop-B/GOME-2) and ozonesondes for the period 2018-2020. We discuss how each data record perceives well-known structures and cycles such as the zonal wave-one, the seasonal cycle and biomass burning periods. Imprints of (sensor-dependent) sampling characteristics are generally less relevant on large scales. However, these can dominate the uncertainty budget when satellite data are used at their finest sampling resolution. Nonetheless, we recognise the signature of the Madden-Julian Oscillation and hints of Kelvin wave activity.
Late Quaternary evolution of the Upper Paraná River, southeast Brazil: a new geomorphological and chronological database
Authors: Oliveira Stefania C. , Pupim Fabiano N. , Stevaux José C. , Assine Mario L.
Published: March 2021

The Paraná River has being extensively studied in terms of its hydrological and sedimentological aspects, but the geological history of its fluvial plain is still poorly understood due to the lack of geochronological data. Most of the published studies are focused on the low and middle reaches, and the region upstream of the Porto Primavera dam is an area almost unknown in terms of geomorphic evolution. Here, we aim to investigate the succession of geological events responsible for the evolution and current configuration of the Upper Paraná River fluvial system, in the stretch between the Jupiá and Porto Primavera Hydroelectric Plants (São Paulo and Mato Grosso states). Thus, we used an integrated approach including remote sensing data, geomorphology, sedimentology, bathymetric profiles, and chronological methods. Four geomorphological compartments were identified and three of these compartments were dated by Optically Stimulated Luminescence (OSL): Unit 1, raised terrace with circular and semicircular ponds (~150 ka); Unit 2, intermediate terrace with small ponds and waterlogged areas (~60 ka); Unit 3, low terrace with preserved paleochannels (~39–35 ka); and Unit 4, current river plain (>9 ka). The geomorphological units were correlated with previous studies downstream of the studied area and their sedimentary characteristics and depositional ages suggest that their genesis is linked to changes in climatic and hydrological conditions during the Late Quaternary. Units 1, 3, and 4 are considered extensions of the geomorphological units Taquaruçu, Fazenda Boa Vista, and Rio Paraná, respectively. Unit 2 is a compartment with unique morphological characteristics, therefore not correlated with units presented in previous works. Further, two main knickpoints were identified, suggesting an important control in the sedimentation and development of the terrace levels. Thus, this work brings new data on the evolutionary history of the Paraná River, which allows us to understand that the development of the terrace levels and the floodplain of the upper reaches are strongly controlled by the climatic changes that occurred during the Late Quaternary.
The Hidden Half: Linking microbial communities to habitat condition and vegetation management in UK blanket bogs
Authors: Burn William , Heinemeyer Andreas , Helgason Thorunn , Glaves David , Morecroft Michael
Published: March 2021

Peatlands are globally valued for the ecosystem services they deliver, including water quality regulation and carbon sequestration. In the UK, blanket bogs are the main peatland habitat and previous work has linked blanket bog management, especially rotational burning of heather vegetation on grousemoors, to impacts on these ecosystem services. However, we still lack a mechanistic, process-level understanding of how peatland management and habitat status is linked to ecosystem service provision, which is mostly driven by soil microbial processes.

Here we examine bacterial and fungal communities across a spectrum of “intact” to degraded UK blanket bogs and under different vegetation management strategies. Sites included grousemoors under burnt and alternative mown or uncut management along with further locations including 'near intact', degraded and restored sites across a UK climatic gradient ranging from Exmoor (South UK), the Peak District (Mid) to the Flow Country (North). Moreover, an experiment was setup at the University of York with peat mesocosms taken from all sites and management/habitat conditions to allow a comparison between field and controlled conditions and assessing root-mediated processes. Using a structural equation model, we linked grousemoor management to specific fungal/bacterial functional groups, and have started to relate this to changes in water quality provision and carbon cycle aspects. This represents a significant step in the effort to use microbial communities as indicators of peatland habitat condition in UK upland blanket bogs. 

 
An introduction to the ULTIMATE project in Japan
Authors: Roh Woosub , Satoh Masaki
Published: March 2021

It is important to evaluate and improve the cloud properties in global non-hydrostatic models like a Nonhydrostatic ICosahedral Atmospheric Model (NICAM, Satoh et al. 2014) using observation data. One of the methods is a radiance-based evaluation using satellite data and a satellite simulator (here Joint simulator, Hashino et al. 2013), which avoids making different settings of the microphysics between retrieval algorithms and NICAM.

The satellite data with active sensors has a limitation to observe the specific case of cloud and precipitation systems. And it is needed to validate satellite observations using in-situ observation. There are intensive observation stations over the Tokyo area, whose domain size is 100 km×100 km. For examples, the High Spectral Resolution Lidar (HSRL, 355 nm), Doppler lidar, and the Cloud Profiling Radar (CPR, 94 GHz) are located in Tokyo. The WInd profiler Network and Data Acquisition System (WINDAS) data is available in Kawaguchiko, Mito, and Kumagaya. Several polarimetric radars cover this area like C-band, Ka band, and X-band phased array.  The ULTIMATE (ULTra sIte for Measuring Atmosphere of Tokyo metropolitan Environment) is proposed to verify and improve high-resolution numerical simulations based on these observation data. In this study, we introduce the preliminary evaluation results of NICAM and applications of the Joint simulator related to the ULTIMATE project.
Sources of water-soluble Brown Carbon at a South-Eastern European Site
Authors: Baliaka Charalampia , Kaltsonoudis Christos , Florou Kalliopi , Jorga Spiro , Vasilakopoulou Christina , Kodros John , Aktypis Andreas , Matrali Angeliki , Paraskevopoulou Despina , Masiol Mauro , Pandis Spyros , Nenes Athanasios
Published: March 2021

Atmospheric brown carbon (BrC) is a highly uncertain, but potentially important contributor to light absorption in the atmosphere. Laboratory and field studies have shown that BrC can be produced from multiple sources, including primary emissions from fossil fuel combustion and biomass burning (BB), as well as secondary formation through a number of reaction pathways. It is currently thought that the dominant source of atmospheric BrC is primary emissions from BB, but relatively few studies demonstrate this in environments with complex source profiles.

A field campaign was conducted during a month-long wintertime period in 2020 on the campus of the University of Peloponnese in the southwest of Patras, Greece which represents an urban site. During this time, ambient filter samples (a total of 35 filters) were collected from which the water-soluble BrC was determined using a semi-automated system similar to Hecobian et al. (2010),  where absorption was measured over a 1 m path length. To measure the BrC, a UV-Vis Spectrophotometer was coupled to a Liquid Waveguide Capillary Cell and the light absorption intensity was recorded at 365 and 700 nm. The latter was used as a reference wavelength. We found that the average BrC absorption in Patras at a wavelength of 365 nm was 8.5 ± 3.9 Mm-1 suggesting that there was significant BrC in the organic aerosol during this period. Attribution of sources of BrC was done using simultaneous chemical composition data observations (primarily organic carbon, black carbon, and nitrate) combined with Positive Matrix Factorization analysis. This analysis showed that in addition to the important role of biomass burning (a contribution of about 20%) and other combustion emissions (also close to 20%), oxidized organic aerosol (approximately 40%) is also a significant contributor to BrC in the study area.

Reference

Hecobian, A., Zhang, X., Zheng, M., Frank, N., Edgerton, E.S., Weber, R.J., 2010. Water-soluble organic aerosol material and the light-absorption characteristics of aqueous extracts measured over the Southeastern United States. Atmos. Chem. Phys. 10, 5965–5977. https://doi.org/10.5194/acp-10-5965-2010

 
CNN-based Multi-Scale Gradient Optimization for Full-Waveform Inversion
Authors: Yang Senlin , Jiang Peng , Ren Yuxiao , Xu Xinji
Published: March 2021

The seismic full waveform inversion (FWI), as one of important ways to obtain the seismic wave velocity, has made rapid development in the last decade. In response to problems of cycle-skipping artifacts, dependence on the initial model, and low-frequency information in FWI, researchers have made many improvements, such as multi-scale envelope inversion and low-frequency extension. Recently, deep learning has been also adopted seismic data processing and interpretation, because of its strong nonlinear mapping ability. However, these works depend on labels used for training heavily, especially for the velocity model in the inversion, which prevents them from real application. Referring to these studies, this work combines low-frequency extension commonly as well as multiscale inversion with deep learning, and proposes a multi-scale FWI gradient optimization method based on CNN. CNN we designed is trained to predict the inversion gradient corresponding to the low-frequency band data in FWI, so that multi-scale gradient optimization can be directly used in multi-scale inversion, expanding the low-frequency information in the actual data and reducing the calculation in FWI. With a specially designed dataset, CNN is trained to optimize the gradients computed from the high-frequency band data by predicting the gradients corresponding to the low-frequency band data and the gradients corresponding to the mid-frequency band data, respectively. The predicted gradients are used in different stages of the multi-scale inversion. The low-frequency gradients are used to invert the initial structural construction so as not to rely on a good initial model, and the high-frequency gradients are used to improve the accuracy of the inversion results. In this way, low-frequency expansion and multiscale inversion can be achieved simultaneously. Our method achieves good results on the initial model for a given uniform wave velocity, effectively alleviating the reliance on the initial model in FWI. This study provides a new idea of combining deep learning and full waveform inversion, which will be effectively used in seismic data processing.
How much of the decadal, coastal sea level variability can we describe by climate modes?
Authors: Royston Samantha , Bamber Jonathan , Bingham Rory
Published: March 2021

It is well known that key climatic variability like the El Niño Southern Oscillation and Pacific Decadal Oscillation dominate steric sea-level variability in the Pacific Ocean and that this variability influences global- and regional-mean sea-level time series. Reducing the known internal variability from these time series reduces trend errors and can elucidate other factors including anthropogenic influence and sea-level acceleration, as has been demonstrated for the open ocean. Here we discuss the influence of key climate modes on coastal, decadal sea-level variability. For coastal stakeholders and managers it is important to understand the decadal-scale and local changes in the rate of sea-level rise in the context of internal variability in order to inform management decisions in the short- to medium-term. We use a 53-year run of a high-resolution NEMO ocean model run, forced by the DRAKKAR reanalysis atmospheric data set and with the global-mean sea level at each timestep removed, to investigate modes of decadal sea-level variability at the coast, in different basins and from different sea-level components. At more than 45% of Pacific Ocean coastal locations, greater than 50% of the decadal sea-level change can be explained by a regression of the leading principal component mode with key climate indices; ENSO in the Pacific Ocean. In different ocean basins, 18.5% to 61.0% of coastal locations have more than 33% of decadal sea-level variance explained by our climate index reconstructions. These areas include coastal regions lacking long-duration or good quality tide gauges for long-term observations such as the North-West Africa coastline. Because of the shallow depth of continental shelves, steric sea-level change propagates onto the shelf as a manometric (mass) sea-level signal. We use a set of tide gauge locations to demonstrate the internal, decadal sea-level change observed at many coasts has a substantial contribution from local, manometric signal that is driven by climate variability.
Trait spaces of non-native plants at community level in the Canary Islands
Authors: Walentowitz Anna , Beierkuhnlein Carl
Published: March 2021

Non-native plants, introduced through anthropogenic vectors, are causing changes at local up to global scales, altering species communities and entire ecosystems, modifying the structure of landscapes and even the functioning of biogeochemical cycles. Ultimately, however, changes induced by non-native plants occur locally at the level of species communities. With ongoing developments towards open-access information about species at increasingly fine spatial scales, the data and tools to better understand the consequences of vegetation changes caused by non-natives are available. Further, islands that commonly have less saturated ecosystems and unoccupied ecological niches with depauperate trophic cascades are particularly susceptible to the establishment of non-native plants and their potential impacts, respectively. Steep environmental gradients, unique plant communities with high percentages of endemism and a long history of human settlement alongside which hundreds of non-native species became established make the Canary Islands a suitable testing ground for invasion ecology. We aim at explaining divergence and overlap of native and non-native trait spaces within and between vegetation communities in this oceanic archipelago in order to assess the functional consequences of plant introductions for communities and ecosystems.

As a profound basis, we compiled a revised flora of the Canary Islands using local and global taxonomic databases combined with recent publications. Plant traits derived from comprehensive open-access sources and additional literature. At community level, we separated native and non-native species and their associated traits.

The analysis revealed strong differences in trait space divergence of non-native vs. native species within different vegetation communities. Surprisingly, certain traits such as woodiness of non-native species do not correlate with the role of this trait in plant communities previously dominated by native species. The inferences we can draw from our results differ from the conclusions made at the level of entire ecosystems, which underlines the relevance of investigating traits at community level.

We encourage implementing further studies at vegetation community level, to understand the direct changes caused by non-native species, build reliable explanatory models, enable targeted conservation measures and ultimately better understand patterns of biodiversity in the Anthropocene.
Meteorological conditions favourable for strong aerosol impacts on clouds
Authors: Trofimov Heido , Toll Velle
Published: March 2021

Pollution tracks in clouds induced by anthropogenic aerosols (Toll et al 2019, Nature, https://doi.org/10.1038/s41586-019-1423-9) are visually detectable ship-track-like quasi-linear polluted cloud features in satellite imagery. Pollution tracks provide a direct way to study aerosol-cloud interactions, the most uncertain mechanism of anthropogenic climate forcing. Here, we study environmental conditions favourable for pollution tracks’ formation. We use meteorological data from in-situ observations and ERA5 reanalysis and cloud properties derived from MODIS retrievals over the period 2000-2019. We detected pollution track occurrences at the anthropogenic air pollution hot spots of Norilsk and Cherepovec in Russia and Thompson in Canada. In Norilsk, there are large Nickel smelters, in Cherepovec, a steel manufacturing plant, and in Thompson nickel mining and milling operations take place. We compare the meteorological conditions of track-days to cloudy no-track-days. Depending on the studied location, polluted cloud tracks occur 2.7% to 3.5% of the time. Preliminary results show track formation dependence on large-scale dynamical situation, atmospheric stability, unperturbed cloud properties and relative humidity below and above clouds. The track formation could be limited by aerosols, aerosol vertical transport and activation or cloud susceptibility. Our results help to reduce the uncertainty associated with the anthropogenic aerosol impacts on clouds.
Evaluation of GRACE RL06 analysis in the Southern Ocean
Authors: Schröter Jens , Androsov Alexey , Lück Christina , Übbing Bernd , Rietbroek Roelof , Danilov Sergey , Kusche Jürgen
Published: March 2021

Space geodetic estimates of ocean bottom pressure (OBP) derived by several analysis centres are evaluated. To this end, an array of 14 in situ bottom pressure recorders has been deployed between South Africa and Antarctica. The continuous measurement period of four years (2011 to 2014) and a recorder spacing of roughly 2.8 degrees latitude allows an in-depth analysis of bottom pressure variability.

Our goal is to relate OBP from GRACE to in situ observations and detect which spatial and temporal features are reproduced. The recorders in the southern part of the transect generally tend to be in better agreement with GRACE and better reflect longer spatial scales of ocean bottom pressure. Over the vast expanse of the Antarctic Circumpolar Current annual and semi-annual cycles are weak (about 1cm equivalent water height (EWH)) and not reproduced well by GRACE. Variability in general amounts to a standard deviation of 2cm. This level is well captured and correlations on the order of 0.5 are found.

Mean values and trends of OBP cannot be identified due to the instrumental setup. Close to the Agulhas Retroflection, signals of up to 30cm EWH are found, which cannot be resolved by GRACE. Our  analysis reveals: GRACE OBP possesses longer space and time scales than in situ OBP and it misses eddy-scale signals. Filtering with DDK4 appears to be preferable to DDK6.

 
Spatial clustering of heavy clustering in ERA-5 precipitation over Europe}
Authors: Le Gall Philomène , Rivoire Pauline , Favre Anne-Catherine , Naveau Philippe , Romppainen-Martius Olivia
Published: March 2021

Extreme precipitation often cause floods and lead to important societal and economical damages. Rainfall is subject to local orography features and their intensities can be highly variable. In this context, identifying climatically coherent regions for extremes is paramount to understand and analyze rainfall at the correct spatial scale. We assume that the region of interest can be partitioned into homogeneous regions. In other words, sub-regions with common marginal distribution except a scale factor. As an example, considering extremes as block maxima or excesses over a threshold, a sub-region corresponds to a constant shape parameter. We develop a non-parametric clustering algorithm based on a ratio of Probability Weighted Moments to identify these homogeneous regions and gather weather stations. By construction this ratio does not depend on the location and scale parameters for the Generalized Extreme Value and Generalized Pareto distributions. Our method has the advantage to only rely on raw precipitation data and not on station covariates.

A simulation data study is performed based on the extended GPD distribution that appears to well capture low, moderate and heavy rainfall intensities. Sensitivity to the number of clusters is analyzed. Results of simulation reveal that the method detects homogeneous regions. We apply our clustering algorithm on ERA-5 precipitation over Europe. We obtain coherent homogeneous regions consistent with local orography. The marginal precipitation behaviour is analyzed through regional fitting of an extended GPD.
Magnetostratigraphy of the Yili Basin indicates Late Cenozonic activity of the Tianshan Mountain, northwestern China
Authors: Xiaoyan Liu , Sihua Yuan , Chunsheng Jin , Xiangdong Bai , Jiyi Jiang , Zhenghong Zhao , Ying Li
Published: March 2021

The Yili basin, sandwiched in the Northern and Southern Tianshan Mountain, is an ideal area to study the eroded histories at the Northern Tianshan Mountain during the late Cenozoic. Massive works have been done on tectonic deformation and uplift in this region. However, due to the lack of biostratigraphic data and effective dating marks, the uplifting time limit of the Tianshan Mountain are still argued by many researchers. In order to constrain the uplift history in the west Tianshan Mountain and provid the late Cenozoic time scale, we carried out a series of studies in the Chinese Yili Basin, fortunately, we acquired a drilling core with a depth of 500 m in the Quarternary depocenter in this basin, which provides the basis for the relevant studies. These results offered basic geological data for protecting against and mitigating earthquake disasters. 

A magnetic stratigraphic study was carried out on the drilling core, combined with three OSL dating data from a natural section adjacent to the drilling hole, an effective time scale was established. There are three main results as follows: (1)The polarity sequences shows 5 normal and 5 reverse polarity zones which can be readily correlated with the Geomagnetic Polarity Time Scale (GPTS2012), dating the core from 3.11Ma to 12Ka. (2) The B/M boundary of magnetic strata in the 500m core in western Yili basin is located in the core 80m and M/G line is located in the core 400m. (3) The sedimentation rate in the western Yili Basin increased rapidly at two periods, ~1.17 to 1.07Ma and ~2.13 to 1.77Ma. 

According to the regional reference data, the peak deposition rate in the range of ~ 2.13 to 1.77Ma is closely related to the Xiyu movement in Northwest China, as a corollary, the sedimentation rate should decrease with the end of Xiyu Movement after ~1.77Ma. Another obvious lithofacies change from ~1.17 to 1.07Ma illustrates there should be a tectonic event in the Tian shan region. This Middle Pleistocene uplift can also be evidenced by the age of volcanism in the Qaidam Basin (northeastern Tibetan Plateau), the existence of thick conglomerate deposits surrounding the uplifted plateau, and the increased sedimentation rate of lacustrine deposits in the between ~1.1 and ~0.9Ma ago, followed by the loess and marine records.
Mineral chemistry and geothermobarometry of the Balıkesir Volcanites (NW Anatolia, Turkey) 
Authors: Ünal Alp , Altunkaynak Şafak
Published: March 2021

Balıkesir Volcanites (BV) are included into the Balıkesir Volcanic Province and contain various products of Oligo-Miocene volcanic activity in NW Anatolia. BV are formed from trachyandesite, andesite and dacite lavas with associated pyroclastic rocks. In this study, we report the petrographical investigations, mineral chemistry results and geothermobarometry calculations of the Balıkesir Volcanites in order to deduce the magma chamber processes and crystallization conditions. Andesites present a mineral composition of plagioclase (An35–50) + amphibole (edenitic hornblende) +biotite ± quartz and opaque minerals. The major phenocryst phases in dacite lavas are plagioclase (An39–53), quartz, amphibole (magnesio-hornblende), biotite, sanidine and opaque minerals. The mineral composition of the trachyandesites, on the other hand, is represented by plagioclase (An38–57) + amphibole (pargasitic hornblende) + biotite + clinopyroxene (endiopside- augite) ± sanidine ± quartz ± opaque minerals. Balıkesir Volcanites present distinct textural properties such as rounded plagioclase phenocrysts with reaction rims, oscillatory zoning, honeycomb and sieve textures in plagioclase, reverse mantled biotite and hornblende crystals. The plagioclase- amphibole geothermobarometry calculations of Balıkesir volcanites indicate that, andesite and dacite lavas present similar crystallization temperature and pressures conditions of 798- 813°C and 1,98- 2.17 kbar. Oppositely, trachyandesites were crystallized under 857°C and 3,72 kbar temperature and pressure conditions. These results show that the andesite and dacite lavas were originated from the same magma chamber with the depth of 7km whereas trachyandesites were evolved in a deeper magma chamber with 13 km depth. Combined mineral chemistry, petrography and geothermobarometry studies indicate that the open system processes such as magma mixing/mingling and/or assimilation fractional crystallization (AFC) were responsible for the textural and compositional variations of the Balıkesir Volcanites.
Introducing AIDE: a Software Suite for Annotating Images with Deep and Active Learning Assistance
Authors: Kellenberger Benjamin , Tuia Devis , Morris Dan
Published: March 2021

Ecological research like wildlife censuses increasingly relies on data on the scale of Terabytes. For example, modern camera trap datasets contain millions of images that require prohibitive amounts of manual labour to be annotated with species, bounding boxes, and the like. Machine learning, especially deep learning [3], could greatly accelerate this task through automated predictions, but involves expansive coding and expert knowledge.

In this abstract we present AIDE, the Annotation Interface for Data-driven Ecology [2]. In a first instance, AIDE is a web-based annotation suite for image labelling with support for concurrent access and scalability, up to the cloud. In a second instance, it tightly integrates deep learning models into the annotation process through active learning [7], where models learn from user-provided labels and in turn select the most relevant images for review from the large pool of unlabelled ones (Fig. 1). The result is a system where users only need to label what is required, which saves time and decreases errors due to fatigue.

Fig. 1: AIDE offers concurrent web image labelling support and uses annotations and deep learning models in an active learning loop.

AIDE includes a comprehensive set of built-in models, such as ResNet [1] for image classification, Faster R-CNN [5] and RetinaNet [4] for object detection, and U-Net [6] for semantic segmentation. All models can be customised and used without having to write a single line of code. Furthermore, AIDE accepts any third-party model with minimal implementation requirements. To complete the package, AIDE offers both user annotation and model prediction evaluation, access control, customisable model training, and more, all through the web browser.

AIDE is fully open source and available under https://github.com/microsoft/aerial_wildlife_detection.

 

References
Evaluation the quality of FORMOSAT-7/COSMIC-2 Observation Data and its application for ionospheric monitoring during the extreme space weather
Authors: Li Ang
Published: March 2021

Owing to the advantages of high vertical resolution, global coverage, high precision, and all-weather operation, GNSS occultation has been widely used for ionospheric weather monitoring and meteorological forecast. Aiming to obtain the meteorological, climatic, and ionospheric information, FORMOSAT-7/COSMIC-2, the successor constellation of COSMIC-1, is jointly launched by the United States and Taiwan on June 25, 2019. As a new generation occultation constellation, COSMIC-2 consists of six low-latitude satellites with an orbital inclination of 24 degrees and an altitude of 520km. In contrast, COSMIC1 consists of the high-latitude satellites with an orbital inclination of 72 degrees and an orbital altitude of 720km. These differences in constellation structure, orbital altitude, and inclination inevitably lead to the difference in observation quality.

 

Firstly, in this contribution, the qualities of satellite-based GNSS observations from COSMIC-2 and COSMIC-1 are both analyzed and compared. The result shows that the satellite-based observation data of COSMIC-2 are improved significantly compared with COSMIC-1. The multipath effect reduced by more than 40%, and the probability of cycle slip decreased by three times. Then the occultation observations of the two constellations are also analyzed. Next, using the observations of COSMIC-2 satellites in 2020, an ionospheric total electron content (TEC) model was established. Finally, the TEC model was adopted for investigating the ionospheric disturbances under extreme space weather in 2020.

 

Keywords: COSMIC-2; Ionospheric TEC Model; Extreme Space Weather
Ice fabrics in natural flows: moving away from pure and simple shear
Authors: Richards Daniel , Pegler Sam , Piazolo Sandra , Harlen Oliver
Published: March 2021

Antarctic ice flow shows deviation from the deformation regimes of pure and simple shear. By analysing the vorticity number from surface velocity data it is found that approximately 80% of the flow is outside these regimes. These deformations are both between pure and simple shear, as well as highly rotational, highlighting the need for fabric predictions away from the commonly studied regimes of pure and simple shear. 

We use the numerical scheme SpecCAF, which has been shown to accurately reproduce experimentally observed fabrics with no free parameters, to study ice fabrics in such general deformations. By exploring the parameter space of temperature and vorticity number, we present a definitive classification of fabrics patterns which arise, and construct a universal regime diagram for ice fabrics under general two-dimensional deformation. We find that intermediate deformations see a smooth transition between a cone-shape fabric and a secondary cluster. We present the first investigation of the fabrics produced in highly rotational deformations, which produce a weak girdle fabric with the axis aligned to the vorticity axis. We also show that across deformation and temperature space fabrics only reach a true steady-state above strains of 200%, and there is significant variation in this across the parameter space.  