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Half-hourly CO2 eddy covariance flux data, associated meteorological data and Sentinel-2 derived vegetation indices (7) for 05/03/2020 - 23/08/2022 [data]

This repository contains all the data used for the article "Monitoring cropland daily carbon dioxide exchange at field scales with Sentinel-2 satellite imagery" by Pia Gottschalk, Aram Kalhori, Zhan Li, Christian Wille, Torsten Sachs. The data are used to exemplify how ground measured CO2 fluxes of an agricultural field can be linked with remotely sensed vegetation indices to provided an upscaling approach for spatial CO2-flux projection. The provided data form the basis for running the data processing scripts sequentially for (re-)producing all statistical analyses, results and figures in the article. The data are given in the formats as used in the data-processing scripts written in R, MATLAB and JavaScript of Google Eearth Engine. All codes for processing the data and a workflow description can be found here. The dataset covers three types of data: half-hourly eddy covariance (EC) data, satellite derived vegetation indices and GIS/image data. Continuous EC CO2 fluxes (03/2020 - 08/2023) are measured at the agricultural site "Heydenhof" in Northeastern Germany. The data file is provided in .mat (MATLAB) format containing the standard EddyPro software output variables which are described in an accompanying meta data file. The land use information used for footprint modeling is included as .jpeg and .png-files for visulisation and as .mat-file to be used for running the footprint modeling script. Sentinel-2 vegetation indices are provided as .csv files. These files are provided for convenience and version control only as the JavaScript for generating Sentinel-2 derived vegetation indices in Google Earth Engine is provided in the associated code repository. Here, the field boundaries are provided as shape file. Data file description: "HEY_LandUse_image.mat": MATLAB file in raster format, containing the land use codes in a 4x4 km raster with a resolution of 1 m used for running the Korman-Meixner foot print model for flux source area attribution. "meta_data_HEY_LandUse_image.txt": description of land use codes used in the "HEY_LandUse_image.mat" "HEY_LandUse_image.png": Visualisation of HEY_LandUse_image.mat. Figure A2 in manuscript. Showing the land use distribution around the measurement tower encoded in the number of land use classes used for foot print modeling. "HEYDENHOF.jpeg": Visualisation of land use classes from digitisation. Auxiliary information. Showing the land use distribution around the measurement tower. "HEY_FluxData_20200304_20220824_all_data.mat": MATLAB data file containing the half-hourly EC measurements plus auxiliary meteorological variables from 04/03/2020 to 24/08/2022 in matrix format with rows being the half-hourly measurements and including the unique time identifier "Timestamp", and "NaN" as missing data value. "meta_data_HEY_FluxData.txt": text file accompanying "HEY_FluxData_20200304_20220824_all_data.mat" containing the variable names, units, format, range and description for the variables of "HEY_FluxData_20200304_20220824_all_data.mat" "TERENO_prec_data_2020_2022.csv": comma separated text file containing the half-hourly precipitation data for the measurement site (HEY) from 01/01/2020 to 13/10/2022. "meta_data_TERENO_prec.txt": text file accompanying " TERENO_prec_data_2020_2022.csv " containing the variable description of the TERENO precipitation data. "HEY_tower_field.zip": zipped shape file outlining the agricultural field used as source area for the satellite data retrieval. "S2.csv": comma separated text file containing the vegetation indices from Sentinel-2 for the agricultural field from 02/03/2020 to 29/08/2022. "meta_data_Sentinel2_S2.txt": text file accompanying "S2.csv" containing the variable description of Sentinel-2 derived vegetation indices, i.e. "S2.csv". "S2_SD.csv": comma separated text file containing the standard deviation of the vegetation indices for the agricultural field from 02/03/2020 to 29/08/2022. "meta_data_Sentinel2_S2_SD.txt": text file accompanying "S2_SD.csv" containing the variable description of the standard deviation for the Sentinel-2 derived vegetation indices.

Code for linking half-hourly CO2 eddy covariance flux data with Sentinel-2 derived vegetation indices (7) for 05/03/2020 - 23/08/2022 [code]

This repository provides the code used for the article "Monitoring cropland daily carbon dioxide exchange at field scales with Sentinel-2 satellite imagery" by Pia Gottschalk, Aram Kalhori, Zhan Li, Christian Wille, Torsten Sachs. The data are used to exemplify how ground measured CO2 fluxes of an agricultural field can be linked with remotely sensed vegetation indices to provided an upscaling approach for spatial CO2-flux projection. The repository contains the codes produced for the article "Monitoring cropland daily carbon dioxide exchange at field scales with Sentinel-2 satellite imagery" by Pia Gottschalk, Aram Kalhori, Zhan Li, Christian Wille, Torsten Sachs. In this article, the authors present how local carbon dioxide (CO2) ground measurements and satellite data can be linked to project CO2 emissions spatially for agriculutral fields. The codes are provided for - footprint analysis and raw flux data quality control (MATLAB codes); - retrieving Sentinel-2 vegetation indices via Google Earth Engine (GEE code); - subsequent quality control, gap-filling and flux partitioning following the MDS approach by Reichstein et al. 2005 implemented by the R-package "REddyProc" (R codes); - statistical analyses of combined EC and Sentinel-2 data (R codes); - code for all figures as displayed in the manuscript (R codes). This software is written in MATLAB, R and JavaScript (GEE). Running the codes (R and .m files (Code)) and loading the data files (CSV files and .mat files (Data)) requires the pre-installation of [R and RStudio] (https://posit.co/downloads/) and (MATLAB). The GEE script runs in a browser and can also be opened/downloaded here: https://code.earthengine.google.com/858361ae4aac7c3fe5227076c9733040 The RStudio 2021.09.0 Build 351 version has been used for developping the R scripts. The land cover classification work was performed in QGIS, v.3.16.11-Hannover. Data were analyzed in both MATLAB and R; and plots created with R (R Core Development Team 2020) in RStudio®.The R codes in this repository contain a suite of external R-packages ("zoo"; "REddyProc"; "Hmisc"; "PerformanceAnalytics") which are required for data analysis in this manuscript. The data to run the codes are published with the DOI https://doi.org/10.5880/GFZ.1.4.2023.008 (Gottschalk et al., 2023).

Longterm monitoring of swarm earthquakes in the western Eger rift

The Bohemian Massif (500-250 Ma), the easternmost part of the Variscan orogenic belt, is one of the largest stable outcrops of pre-Permian rocks in Central and Western Europe. This region has persistent geodynamic activity that is clearly linked to upper mantle, and offers a globally unique location for studying intra-continental earthquake swarm (ES) seismicity in combination with deep crust and mantle degassing as well as their interaction with the deep biosphere. The main questions regarding seismicity, microbial life and origin, and heat flow are all linked by the common questions of fluid flow, pathways, and composition. The ICDP project 'Drilling the Eger Rift' aims to develop the most modern, comprehensive laboratory at depth worldwide for the study of ES, crustal fluid flow, mantle-derived CO2 and He degassing, and processes of the deep biosphere. In order to reach a new level of high-frequency, near source, and multi-parameter observation of ES and related phenomena, such a laboratory will comprise of a high-frequency 3D seismic array with a set of four shallow boreholes, combined with modern continuous real-time fluid monitoring at depth (the shallow boreholes) and the study of deep biosphere. Waveform data is available from the GEOFON data centre, under network code 1D.

Eifel Large-N Seismic Network (ELSN)

The Eifel Large-N Seismic Network is a concentric network of about 80km aperture around the Laacher See. Instrumentation consists of broad band seismometers, short period instruments (1Hz eigenfrequency) and 4.5Hz geophones. While the broadband and short period stations cover the area rather homogeneously for about 12 month, the geophone stations were moved after 6 month from a layout focussed on the closer vicinity of the Laacher See onto a line crossing the network from south-west to north-east with a dense station spacing. The goal of the experiment is the structural investigation of the feeding system of the East Eifel and a detailed study of the tectonic and volcanic seismic activity in this area. Waveform data is available from the GEOFON data centre, under network code 6E.

Customised focus maps and resultant CVT-based aggregation entities for Lima and Callao (Peru)

This data publication is composed by two main folders: (1) “Focus_map_construction” and (2) “CVT_models”. The first one contains the individual raster inputs (tsunami inundation and population distribution) that are combined to construct two different focus maps for the cities of Lima and Callao (Peru). The reader can find a more complete description about the focus map concept in Pittore (2015). These raster focus maps are used as inputs to generate variable-resolution CVT (Central Voronoi Tessellation) geocells following the method presented in Pittore et al., (2020). They are vector-based data (ESRI shapefiles) that are stored in the second folder. These resultant CVT-geocells are used by Gomez-Zapata et al., (2021) as spatial aggregation boundaries to represent the residential building portfolio for the cities of Lima and Callao (Peru).

The value of the German marine environment

Die europäischen Küsten und Meeresgewässer, einschließlich der Nord- und Ostsee, gehören zu den am intensivsten genutzten Meeresgebieten der Welt. Zu den gängigsten Nutzungsarten der beiden Meere gehören Fischerei, Schifffahrt und Tourismus, die wichtige wirtschaftliche Aktivitäten darstellen, aber auch Druck auf die Meeresumwelt ausüben. Im Rahmen dieses Projektes schätzen wir den Nutzen für die deutsche Bevölkerung ab, der entstehen würde, wenn in den deutschen Meeresgewässern, d.h. den deutschen Teilen von Nord- und Ostsee, ein "Guter Umweltzustand" (wie in der Meeresstrategie-Rahmenrichtlinie (MSFD) definiert, die im Juni 2008 von der Europäischen Union (EU) verabschiedet wurde (EU 2008)) erreicht würde. Dazu leiten wir die Zahlungsbereitschaft (willingness-to-pay, WTP) der deutschen Bevölkerung für das Erreichen eines GES in der deutschen Meeresumwelt mit Hilfe der Contingent Valuation Methode (CVM) ab. Zusätzlich zum CVM wurde ein Choice-Experiment (CE) in die Befragung aufgenommen. Die Analyse der kontingenten Bewertung wurde mit Hilfe von drei verschiedenen Modellen durchgeführt, die auf unterschiedlichen Teilmengen der Stichprobendaten basieren. Eines der Grundmodelle wurde mit Hilfe einer OLS-Schätzung berechnet. Das zweite Grundmodell ist ein Tobit-Modell, das zur Vorhersage der von den Umfrageteilnehmern gewählten Intervalle verwendet wird. Aufgrund der geringen Erklärungskraft dieser Basismodelle wurde als dritter Ansatz für eine erweiterte Analyse des WTP der Deutschen ein "Double Hurdle" - Modell gewählt. Ausgangspunkt für die Analyse der Choice-Daten ist das Random-Utility-Modell (RUM) (McFadden's 1974). Aufbauend auf Annahmen bezüglich der Fehlerterme erhält man das bedingte Logit (CL)-Modell. Da das CL-Modell davon ausgeht, dass alle Individuen die gleichen Präferenzen haben, wenden wir auch ein "Latent Class" - Modell (LC) an, das es uns erlaubt, unbeobachtete Heterogenität in den Geschmacksempfindlichkeiten zu erfassen. Es zeigt sich, dass der aggregierte Nutzen des Erreichens eines GES in der deutschen Nord- und Ostsee bis 2040 3,908 Mrd. EUR pro Jahr für das grundlegende Intervall-Regressionsmodell (durchschnittliche Zahlungsbereitschaft = 56,24 EUR) ohne Protestantworten und 4,566 Mrd. EUR pro Jahr für das grundlegende OLS-Regressionsmodell (durchschnittliche Zahlungsbereitschaft = 65,71 EUR) ohne Protestantworten beträgt. Die mit dem "Double Hurdle" - Modell geschätzte mittlere individuelle Zahlungsbereitschaft beträgt 61,6 EUR pro Person und Jahr, was zu einem mittleren Gesamtnutzen des Erreichens eines GES in der deutschen Nord- und Ostsee bis 2040 führt, der sich auf 2,889 Mrd. EUR pro Jahr beläuft. Quelle: Forschungsbericht

Nanostructured Surface Acitivated ultra-thin Oxygen Transport Membrane (NASA-OTM)

The main objective of the proposed project is the development and industry-driven evaluation of highly stable and highly oxygen-permeable nano-structured oxygen transport membrane (OTM) assemblies with infinite selectivity for oxygen separation from air. The new approach proposed to reach this objective is the development of ultra thin membrane layers by e.g. CVD, PVD or Sol-Gel techniques with catalytic activation of the surfaces. This approach is supposed to make available highly stable membrane materials, which are currently out of discussion as the oxygen permeation measured on thick membranes is too low. Sufficiently high oxygen fluxes shall be obtained by: (i) ultra thin membrane layers on porous supports to minimize diffusion barriers; (ii) catalytic surface activation to overcome slow surface exchange/reaction kinetics; and (iii) thin-film nano-structuring, generating new diffusion paths through the grain boundaries in a nano-crystalline matrix. The membrane development is supported by thermo-mechanical modelling as well as atomistic modelling of transport properties. The produced oxygen is provided to Oxyfuel power plants or chemical processes such as oxidative coupling of methane (OCM) to higher hydrocarbons or HCN synthesis, which will contribute in a way to the mitigation of CO2 emissions. Oxyfuel power plants combust fuels using pure oxygen forming primarily CO2 and H2O making it much easier and cheaper to capture the CO2 than by using air. The major advantages of OTM are significantly lower efficiency losses than conventional technologies and the in principle infinite oxygen selectivity. OCM produces higher hydrocarbons directly without forming CO2 and HCN synthesis can be improved by process intensification resulting in energy and subsequent CO2 savings.

FP5-EESD, Substrat- und Sperrschichtoptimierung fuer im CVD-Verfahren hergestellte Duennschicht-Siliziumkristall-Solarzellen

Objective: A consortium has been formed by partners stemming from research and industry in order to make a further step towards the development of a cost-effective thin-film crystalline Si solar cell technology, based on thermally assisted Chemical Vapour Deposition (CVD) as deposition technique. This project should result in a thin-film crystalline Si low-cost PV module with a competitive cost/Wp. Description of work: The numerous possible options for thin-film crystalline Si solar cells (for substrate and barrier layer) and the absence of real progress on the level of equipment development for large-volume Si-layer deposition bear an inherent risk for subcritical research in this area. The consortium defined a clear strategy as far as substrates and deposition system are concerned. - Concerning the substrates, the number of options has been reduced to 3 options (Si-ribbons, a conductive ceramic: Si-infiltrated SiAlON and an insulating ceramic: SiAlON). - Together with the development and optimisation of the barrier layers, 4 technically relevant substrate/barrier layers schemes are investigated on cell level: Si-ribbons with and without barrier layer, Si-infiltrated SiAlON-substrates with a conductive SiC-layer, SiAlON-substrates and Si-ribbons with an insulating oxide barrier layer. After the Midterm Assessment, the number of substrate/barrier schemes is reduced to 2 (a conductive and non-conductive scheme), based on the results of a laboratory-type comparison of cells and the first cost projections. - Concerning the development of a high-throughput CVD-system, first steps toward a continuous Si-deposition system are taken. The consortium wishes to assess and reduce the running costs of such system. Specifically the costs associated with waste treatment and a reduction of the gas consumption through a H2-recirculation system will be looked at in more detail . In the first phase of the project these aspects will be studied. After the Midterm Assessment this deposition system will be intensively used for the growth of the Si-layers on the selected substrates, which will be processed into solar cells using processes, compatible with the industrial reality. Expected Results and Exploitation Plans: - The selection of a suitable low-cost substrate, compatible with Si-deposition by means of thermally-assisted Chemical Vapour Deposition (and possibly a liquid phase recrystallisation step); - The development of suitable barrier layers to prevent impurity indiffusion from the low-cost substrate into the active layer and to optimise internal reflection; - The assessment of a continuous high-throughput CVD-reactor, compatible with the requirements of the solar cell industry; - A module of 30x30 cm2 on the selected conductive substrate/barrier layer combination with an efficiency = 12 per cent obtained by a two-side contacting technology. Prime Contractor: Interuniversity microelectronics centre, microsyst4ems, components and packaging advanced solar cells

Development of a Mobile Field Instrument for the Fast Simultaneous Measurement of OH- and HO2 Radicals in the Troposphere by High-Repetition Rate Laser-Induced Fluorescence

Objective: This project aims to develop an operative mobile field instrument for the highly sensitive, fast in-situ measurement of OH and HO2 in the troposphere. The oxidizing capacity of the troposphere is mainly determined by the concentration of hydroxyl-radicals (OH), which control the removal of most naturally and anthropogenically produced atmospheric trace gases. Thus, the understanding of the tropospheric chemistry requires the direct measurement of OH-radicals in the atmosphere. There is an urgent need for highly sensitive instruments that can measure tropospheric OH-concentrations with good temporal and spatial resolution. Furthermore, simultaneous measurements of hydroperoxy-radicals (HO2) are needed to assist the interpretation of chemistry. The OH-radicals are sampled by fast gas-expansion of ambient air into a low pressure fluorescence chamber and are detected by laser-induced fluorescence (LIF) using the excitation wavelength 308 nm. A high-repetition rate laser system will be used to give adequate sensitivity (105 OH/cm3 in a few minutes). This technique is essentially free from interferences by laser generated OH. The nearly simultaneous measurement is achieved by chemical conversion of atmospheric HO2 into OH by titration with NO. The high-repetition rate laser system to be used in this project will be a combination of an optimized copper vapour laser (CVL) and a small-bandwidth tunable dye laser that will be modified and optimized for reliable field operation. The laser system will be integrated into an existing LIF experiment which will be developed into an operative mobile field instrument for ground based measurements. The instrument will be tested during a comprehensive photochemistry field campaign at Juelich. In a second part of this project, a novel concept for a tunable CVL-pumped Ti doped sapphire laser will be studied for use as a compact and lightweight laser radiation source, designed for an advanced OH/HO2 measurement system that could be operated on board of a small airplane.

Improving Engine Performance and Efficiency by Minimization of Knock Probability (MinKnock)

Internal combustion (IC) engines are by far the major power sources for road transportation today. The limitation of natural oil resources, concerns about global warming due to carbon dioxide and the poor air quality in cities are the driving forces for research development of alternative concepts such as battery electric and fuel cell vehicles. Still IC-engines will play a major role within the next 10-15 years in road transportation due to the potential for the increase of efficiency and the reduction of pollutant emissions, the available infrastructure for fuel, the reliability, the production costs and customer acceptance. Therefore research and development activities on IC-engines are of significant importance for Europe's contribution to climate preservation, pollutant emission minimisation and the ability of the automotive industry to create high employment. In combination with the Euro IV and V emission limits and the likely new emission standards, the already very low carbon dioxide emission levels of gasoline engines have still to be further improved to meet the Kyoto targets. Current configurations of engine combustion systems for low emissions combined with after-treatment systems designed to achieve the new emission standards, are reducing engine efficiency by 2-10 percent or even more. The compensation of these effects and the further improvement of efficiency requires new concepts as DGI, Down-Sizing, turbo charging or CAI (Controlled Auto Ignition). These technologies require very detailed knowledge of all physical and chemical processes related to engines as well as the ability to simulate and measure these processes in order to turn over significant optimisation potential. Up to date, the optimisation of existing engines and the development of new engines concepts like DGI, Down-Sizing, turbo charging or CAI is still a challenge for engine developers considering high loads over the entire speed range. This is mostly due to the knocking phenomenon, which is still in an early stage of understanding, although there have been considerable activities in this area. Describing and even predicting knocking is a tedious task, requiring detailed knowledge of all the processes occurring in the combustion chamber. Consequently, a better understanding of engine knock by means of CFD1 simulation and detailed experiments could strongly support this optimisation and development process. The objective of the proposed project is to provide a better understanding of how engine knock is initiated and influenced by fuel and engine parameters. Advanced measurement techniques will be employed and simulation tools will be developed. The proposed work will complement current European and national projects and will be fully integrated in the LEVEL Cluster. ...

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