scholarly journals HELGES: Helmholtz Laboratory for the Geochemistry of the Earth Surface

2016 ◽  
Vol 2 ◽  
Author(s):  
Friedhelm Von Blanckenburg ◽  
Hella Wittmann ◽  
Jan A. Schuessler
Keyword(s):  
Spatial Scales ◽  
Soil Formation ◽  
Research Centre ◽  
Earth Surface ◽  
Turnover Rates ◽  
Weathering Processes ◽  
Erosion Rates ◽  
Complex Interactions ◽  
The Earth ◽  
Geomorphological Changes

New developments in Geochemistry during the last two decades have revolutionized our understanding of the processes that shape Earth's surface. Here, complex interactions occur between the tectonic forces acting from within the Earth and the exogenic forces like climate that are strongly modulated by biota and, increasingly today, by human activity. Within the Helmholtz Laboratory for the Geochemistry of the Earth Surface (HELGES) of the Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences, it is our goal to quantify the rates and fluxes of these processes in detail and to develop new techniques to fingerprint them over various temporal and spatial scales. We use mass spectrometry facilities to analyze metal stable isotopes, element concentrations and cosmogenic nuclides to fingerprint and quantify geomorphological changes driven by erosion and weathering processes. We use these novel geochemical tools, to quantify, for example, the recycling of metals in plants after their release during weathering of rocks and soils, soil formation and its erosion rates, and mechanisms and speed of sediment transport through drainage basins. Our research is thus dedicated towards understanding material turnover rates at the Earth's surface by using geochemical fingerprints.

Basis for the technique of the external control of the optical equipment for the remote sensing of the Earth surface

1997 ◽  
Vol 3 (3-4) ◽  
pp. 50-53
Author(s):  
O.D. Fedorovskyi ◽  
◽  
V.I. Kononov ◽  
K.Yu. Sukhanov ◽  
◽  
...  
Keyword(s):  
Remote Sensing ◽  
External Control ◽  
Earth Surface ◽  
The Earth

ESTIMATION OF THE EARTH SURFACE TEMPERATURE BY HIMAWARI-8/AHI

2016 ◽  
Vol 72 (2) ◽  
pp. II_1-II_6 ◽  
Author(s):  
Yuuki UCHIDA ◽  
Tomohito ASAKA ◽  
Takashi NONAKA ◽  
Keishi IWASHITA ◽  
Toshiro SUGIMURA
Keyword(s):  
Surface Temperature ◽  
Earth Surface ◽  
The Earth

scholarly journals Quantifying Root-Soil Interactions in Cover Crop Systems: A Review

Agriculture ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 218
Author(s):  
Cameron M. Ogilvie ◽  
Waqar Ashiq ◽  
Hiteshkumar B. Vasava ◽  
Asim Biswas
Keyword(s):  
Water Content ◽  
Soil Water ◽  
Soil Water Content ◽  
Cover Crops ◽  
Cover Crop ◽  
Soil Formation ◽  
Soil Physical Properties ◽  
Nutrient Losses ◽  
Complex Interactions ◽  
Soil Ecosystems

Plant roots are an integral part of soil ecosystems and contribute to various services, including carbon and nutrient cycling, weathering, and soil formation. They also modify soil physical properties (e.g., soil water content, pore size distribution, and bulk density) and impact subsequent crops’ growth. Cover crops have been reported to improve soil and environmental quality by reducing nutrient losses, improving soil water content, and increasing soil organic matter. Understanding the complex interactions between cover crop roots and soil (RS) is of utmost importance. However, cover crop RS interactions have not been critically reviewed. In this article, we investigated the nature of cover crop physical RS interactions and explored the emerging technologies for their study. We also assessed technologies that may be readily applied to the study of physical RS interactions in cover crop systems and discussed ways to improve related research in the future.

scholarly journals Sequential modelling of the Earth’s core magnetic field

2020 ◽  
Vol 72 (1) ◽  
Author(s):  
Guillaume Ropp ◽  
Vincent Lesur ◽  
Julien Baerenzung ◽  
Matthias Holschneider
Keyword(s):  
Magnetic Field ◽  
Prior Information ◽  
Spatial Scales ◽  
Model Parameters ◽  
International Geomagnetic Reference Field ◽  
The Earth ◽  
Temporal And Spatial ◽  
Different Sources ◽  
Original Approach ◽  
Modelling Approach

Abstract We describe a new, original approach to the modelling of the Earth’s magnetic field. The overall objective of this study is to reliably render fast variations of the core field and its secular variation. This method combines a sequential modelling approach, a Kalman filter, and a correlation-based modelling step. Sources that most significantly contribute to the field measured at the surface of the Earth are modelled. Their separation is based on strong prior information on their spatial and temporal behaviours. We obtain a time series of model distributions which display behaviours similar to those of recent models based on more classic approaches, particularly at large temporal and spatial scales. Interesting new features and periodicities are visible in our models at smaller time and spatial scales. An important aspect of our method is to yield reliable error bars for all model parameters. These errors, however, are only as reliable as the description of the different sources and the prior information used are realistic. Finally, we used a slightly different version of our method to produce candidate models for the thirteenth edition of the International Geomagnetic Reference Field.

A multi-decade assessment of the impact of large fire events on sediment redistribution using LAPSUS - the Águeda catchment, north-central Portugal

2021 ◽  
Author(s):  
Dante Föllmi ◽  
Jantiene Baartman ◽  
João Pedro Nunes ◽  
Akli Benali
Keyword(s):  
Soil Depth ◽  
Spatial Scales ◽  
Fire Severity ◽  
Sediment Dynamics ◽  
Land Uses ◽  
Erosion Rates ◽  
Erosion Processes ◽  
Sediment Redistribution ◽  
Central Portugal ◽  
The Impact

<p><strong>Abstract</strong></p><p>Wildfires have become an increasing threat for Mediterranean ecosystems, due to increasing climate change induced wildfire activity and changing land management practices. Apart from the initial risk, fire can alter the soil in various ways depending on different fire severities and thus post-fire erosion processes are an important component in assessing wildfires’ negative effects. Recent post-fire erosion (modelling) studies often focus on a short time window and lack the attention for sediment dynamics at larger spatial scales. Yet, these large spatial and temporal scales are fundamental for a better understanding of catchment sediment dynamics and long-term destructive effects of multiple fires on post-fire erosion processes. In this study the landscape evolution model LAPSUS was used to simulate erosion and deposition in the 404 km<sup>2</sup> Águeda catchment in northern-central Portugal over a 41 year (1979-2020) timespan. To include variation in fire severity and its impact on the soil four burnt severity classes, represented by the difference Normalized Burn Ratio (dNBR), were parameterized. Although model calibration was difficult due to lack of spatial and temporal measured data, the results show that average post-fire net erosion rates were significantly higher in the wildfire scenarios (5.95 ton ha<sup>-1</sup> yr<sup>-1</sup>) compared to those of a non-wildfire scenario (0.58 ton ha<sup>-1</sup> yr<sup>-1</sup>). Furthermore, erosion values increased with a higher level of burnt severity and multiple fires increased the overall sediment build-up in the catchment, fostering an increase in background sediment yield. Simulated erosion patterns showed great spatial variability with large deposition and erosion rates inside streams. Due to this variability, it was difficult to identify land uses that were most sensitive for post-fire erosion, because some land-uses were located in more erosion-sensitive areas (e.g. streams, gullies) or were more affected by high burnt severity levels than others. Despite these limitations, LAPSUS performed well on addressing spatial sediment processes and has the ability to contribute to pre-fire management strategies. For instance, the percentage soil loss map (i.e. comparison of erosion and soil depth maps) could identify locations at risk.</p>

Effect of non-tidal station loading on Lunar Laser Ranging observatories and on the estimation of Earth orientation parameters

2021 ◽  
Author(s):  
Vishwa Vijay Singh ◽  
Liliane Biskupek ◽  
Jürgen Müller ◽  
Mingyue Zhang
Keyword(s):  
Research Centre ◽  
Laser Ranging ◽  
The Moon ◽  
Lunar Laser Ranging ◽  
Earth Orientation Parameters ◽  
Tidal Station ◽  
Earth Orientation ◽  
The Earth ◽  
Lunar Laser ◽  
Orientation Parameters

<p>The distance between the observatories on Earth and the retro-reflectors on the Moon has been regularly observed by the Lunar Laser Ranging (LLR) experiment since 1970. In the recent years, observations with bigger telescopes (APOLLO) and at infra-red wavelength (OCA) are carried out, resulting in a better distribution of precise LLR data over the lunar orbit and the observed retro-reflectors on the Moon, and a higher number of LLR observations in total. Providing the longest time series of any space geodetic technique for studying the Earth-Moon dynamics, LLR can also support the estimation of Earth orientation parameters (EOP), like UT1. The increased number of highly accurate LLR observations enables a more accurate estimation of the EOP. In this study, we add the effect of non-tidal station loading (NTSL) in the analysis of the LLR data, and determine post-fit residuals and EOP. The non-tidal loading datasets provided by the German Research Centre for Geosciences (GFZ), the International Mass Loading Service (IMLS), and the EOST loading service of University of Strasbourg in France are included as corrections to the coordinates of the LLR observatories, in addition to the standard corrections suggested by the International Earth Rotation and Reference Systems Service (IERS) 2010 conventions. The Earth surface deforms up to the centimetre level due to the effect of NTSL. By considering this effect in the Institute of Geodesy (IfE) LLR model (called ‘LUNAR’), we obtain a change in the uncertainties of the estimated station coordinates resulting in an up to 1% improvement, an improvement in the post-fit LLR residuals of up to 9%, and a decrease in the power of the annual signal in the LLR post-fit residuals of up to 57%. In a second part of the study, we investigate whether the modelling of NTSL leads to an improvement in the determination of EOP from LLR data. Recent results will be presented.</p>

Project rAn:  Games to promote awareness of natural disasters in young students

2021 ◽  
Author(s):  
Jose Saraiva ◽  
Priscila Doran ◽  
Rosa Doran
Keyword(s):  
Natural Disasters ◽  
Natural Disaster ◽  
Serious Game ◽  
Early Age ◽  
Human Settlements ◽  
Complex Interactions ◽  
The Earth ◽  
The Subject ◽  
Young Students

<p>The Earth is an amazing planet. However, it is also an unpredictable and wild one – part of its many charms. Atmosphere, hydrosphere, geosphere are alive, and can unleash awesome forces on the whole planet, including the biosphere, of which we humans are part. It’s important to make young students aware of the fact that we all live in a planet that was not made specifically for humans, and that it is absolutely imperative that our species learns to respect it and its rhythms and cycles.</p><p>Human settlements are often located in pleasant areas, with little or no concern about their vulnerability to natural disasters. Authorities, local, regional and national, should make preparations to prevent and mitigate their occurrence, of course. But at least as important is the need to create awareness in the citizens, so they can face any disaster and react in a calm and orderly way. That task must begin at an early age. Other than learning to deal with natural disasters and avoiding panic, schoolkids can exert a powerful influence in the adult members of their families and alert them to the measures they should adopt to prepare for any future occurrence.</p><p>In project rAn, EU-funded, we aim to develop a serious game, adjusted to the age of the targets, that will teach them about four types of natural disaster (earthquakes, floods, fires and storms) and make them aware of how to prepare and react in case of one of them striking their city or village. The game will be easy to play, and given the small age of the players will not feature complex interactions. It will include contributions from teachers and groups of students from all Europe, that will be challenged to create small games on the subject, using the Scratch language.    </p>

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