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(Appendix A) Radiolarian abundances in ODP Hole 175-1084A

<p>The changing composition of radiolarian faunas from late Neogene deep-sea sediments has been used in recent years as a proxy for changes in marine paleoproductivity. We examine radiolarian faunas, organic carbon content (TOC), opal and coarse-fraction components over the last 270,000 years in sediments from ODP Hole 1084A, drilled in a high productivity upwelling region within the Benguela Upwelling System off the west coast of Africa. Age control is provided by stable oxygen isotope measurements of benthic foraminifera. Prior research has established that late Pleistocene glacial intervals in this upwelling system generally had higher productivity than interglacials. The radiolarian WADE (water-depth ecology) paleoproductivity index correlates well with TOC and opal in these samples, and all three parameters change in synchrony with the benthic isotope curve over all but the MIS 5e–6 time interval. WADE inferred productivity is significantly higher in glacials than interglacials. We conclude that the WADE index is a useful proxy for paleoproductivity at this location, as are also opal and organic carbon accumulation rates. Carbonate and carbonate based indices such as the accumulation rate of benthic foraminifera (BFAR) by contrast do not correlate well either to productivity indices or to the glacial–interglacial cycle, and are interpreted to primarily reflect carbonate dissolution.</p>

Stable isotope and hydrochemical composition of fresh water in rivers of the Basin of Pöhlde, and the Rhume karst springs, Germany, under different seasonal and discharge conditions

The hydrochemical and stable isotope composition of fresh surface water in rivers (Sieber and Oder) of a karst area in the southwestern foreland of the Harz Mountains, Germany, was investigated at several occasions between years 1986 and 1992. The campaigns covered different seasonal and hydrological (discharge) conditions, including a snow-melt induced high water at the rivers. Aim of the study was the investigation of the impact of discharge conditions at the river water loosing water to underground passage in the Basin of Pöhlde, dissolving carbonate and sulfate minerals in the karst aquifers, and reappearing in the karst springs of the Rhume river. Besides physical characterization, hydrochemical major and minor elements were measaured, as weill as the carbon isotope composition of DIC, the sulfur and oxygen isotope composition of sulfate, and the oxygen isotope composition of water. Results reflect the impact of hydrological conditions on the subterrestrial carbon and sulfur cycles.

Seasonal Dataset of DO, δ¹⁸ODO and Biogeochemical Parameters in the Danube River (2023–2024)

This dataset contains dissolved oxygen (DO) concentrations, stable oxygen isotope ratios of DO (δ¹⁸ODO), particulate organic carbon (POC) concentrations, and respiration/photosynthesis (R/P) ratios, along with corresponding parameters (temperature, δ¹⁸OH2O, nitrate) collected from the Danube River and its key tributaries during five seasonal sampling campaigns in 2023 and 2024. Water samples were collected using a weighted 2 L sampling bottle submerged 1–2 meters below the surface, with sampling conducted from the river center via bridges or passenger boats, and occasionally from the riverbank. In situ temperature measurements were taken with a multiparameter instrument (HQ40d, HACH™, Loveland, CO, USA). δ¹⁸ODO was analyzed using a modified automated equilibration system (Gasbench II, ThermoFisher Scientific™) coupled to a DELTA V Advantage isotope ratio mass spectrometer (IRMS, ThermoFisher Scientific™). This dataset captures seasonal variations in DO dynamics and provides valuable insights into oxygen sources and sinks within the Danube River. The data support the study of biogeochemical cycling in large river systems and can inform ecosystem management and conservation strategies in the face of environmental and climate change.

Timeseries of binned benthic stable carbon isotope from ODP Site 162-982,130-807 and ODP Site 162-982

This dataset contains C. wuellerstorfi stable carbon isotope values binned by marine isotope stage from ODP Site 162-807 and ODP Site 162-982 that span the last 4.5 million years (Feng et al. 2022; Venz et al. 1999, 2002; Hodell & Venz-Curtis 2006). This isotope gradient reflects the accumulation of respired and disequilibrium carbon in the deep Pacific ocean relative to the North Atlantic. Also included are binned probstack δ18O (Ahn et al., 2017) and ΔGMST (Clark et al., 2024) values for comparison to the binned stable carbon isotope values.

The iron-snow regime in Fe-FeS cores: a numerical and experimental approach

In the Earth, the dynamo action is strongly linked to core freezing. There is a solid inner core, the growth of which provides a buoyancy flux that drives the dynamo. The buoyancy in this case derives from a difference in composition between the solid inner core and the fluid outer core. In planetary bodies smaller than the Earth, however, this core differentiation process may differ - Fe may precipitate at the core-mantle boundary (CMB) rather than in the center and may fall as iron snow and initially remelt with greater depth. A chemical stable sedimentation zone develops that comprises with time the entire core - at that time a solid inner core starts to grow. The dynamics of this system is not well understood and also whether it can generate a magnetic field or not. The Jovian moon Ganymede, which shows a present-day magnetic dipole field, is a candidate for which such a scenario has been suggested. We plan to study this Fe-snow regime with both a numerical and experimental approach. In the numerical study, we use a 2D/3D thermo-chemical convection model that considers crystallization and sinking of iron crystals together with the dynamics of the liquid core phase (for the 3D case the influence of the rotation of the Fe snow process is further studied).The numerical calculations will be complemented by two series of experiments: (1) investigations in metal alloys by means of X-ray radioscopy, and (2) measurements in transparent analogues by optical techniques. The experiments will examine typical features of the iron snow regime. On the one hand they will serve as a tool to validate the numerical approach and on the other hand they will yield important insight into sub-processes of the iron snow regime, which cannot be accessed within the numerical approach due to their complexity.

Repository der KI-Ideenwerkstatt: faszination_naechtlicher_vogelzug

# Faszination Nächtlicher Vogelzug A web component for visualizing migratory bird detections on an interactive map. Built with React, MapLibre GL, and the BirdWeather GraphQL API. Designed for embedding into CMS platforms like Contao. ## Tech Stack - **React 19** + **TypeScript** (Vite) - **MapLibre GL** -- WebGL map rendering (Stadia Maps dark theme) - **Supercluster** -- per-species spatial clustering - **Apollo Client 4** -- GraphQL data fetching with caching - **GraphQL Code Generation** -- type-safe queries from BirdWeather schema - **SunCalc** -- astronomical day/night calculations - **Tailwind CSS 4** + **Ant Design 6** -- UI - **Vitest** -- testing ## Features - **Interactive map** with color-coded detection clusters per species - **Timeline animation** with autoplay, step controls, and throttled slider - **Night-only mode** that compresses inactive daytime hours using SunCalc sunrise/sunset calculations - **Day/night overlay** showing the terminator (day/night boundary) as a real-time GeoJSON polygon - **Species search** with autocomplete and availability checking per map viewport - **Supplementary layers** (light pollution, noise mapping via WMS) - **Web component** (`<zug-birdnet>`) for CMS embedding without routing ## Project Structure ``` src/ main.tsx Web component registration App.tsx Root component, species selection state api/ fragments.ts GraphQL fragments (DetectionItem, SpeciesItem) queries.ts GraphQL queries (detections, species, search) useDetections.ts Detection fetch hook with prefetching components/ DatesProvider.tsx Time state context (date range, animation, night mode) MapProvider.tsx MapLibre GL instance context SpeciesDropdown.tsx Species selection with search autocomplete Timeline.tsx Date picker, animation slider, playback controls LayersDropdown.tsx Toggle info layers (light pollution, noise) InfoPopup.tsx Map info marker popups map/ Map.tsx MapLibre GL initialization and rendering clusterUtils.ts Per-species Supercluster index creation colorUtils.ts MapLibre paint expression builder mapStyles.ts Map layer definitions usePersistentColors.ts Stable color assignment per species infopoints.ts Static info marker data lib/ apollo-client.ts Apollo Client with cache type policies buildAvailableSpeciesQuery.ts Dynamic aliased query generation getDayPolygon.ts Day/night terminator polygon calculation getTranslatedSpeciesName.ts i18n species name lookup isNotNull.ts, hasNonNullProp.ts Type guard utilities throttle.ts Throttle utility gql/ Auto-generated GraphQL types (do not edit) ``` ## Architecture Three React context providers compose the application: ``` ApolloProvider GraphQL caching and data fetching DatesProvider Date range, animation state, night-only time segments MapProvider MapLibre GL map instance App Species selection, filtered detections, color mapping ``` **Data flow:** Apollo fetches detections for the current bounding box and date range. Detections are filtered client-side by the visualisation time window (controlled by the timeline slider). Each species gets its own Supercluster index for independent color-coded clustering. Cluster features are rendered via MapLibre GL layers with dynamic `match` paint expressions. **GraphQL:** Queries and fragments are defined in `src/api/` and typed via `@graphql-codegen/client-preset`. Run `npm run codegen` after schema changes to regenerate `src/gql/`. ## Development ```sh npm install npm run dev ``` The dev server uses a self-signed SSL certificate via `@vitejs/plugin-basic-ssl`. Accept the browser warning on first visit. Other commands: ```sh npm run build # Production build npm run test # Run tests npm run lint # ESLint npm run codegen # Regenerate GraphQL types ``` ## Build & Integration Run `npm run build` to produce the `dist/` folder. The build outputs stable filenames (no hashes) and splits vendor dependencies into separate chunks for caching: ``` dist/ index.html assets/ index.css App styles (Tailwind + Ant Design) index.js Application code, React, Supercluster, dayjs, SunCalc maplibre.js MapLibre GL antd.js Ant Design + icons apollo.js Apollo Client + graphql ``` Only `index.js` changes on application updates. Vendor chunks are cache-stable between deploys. To embed the web component, include the built CSS and JS, then use the custom element: ```html <link rel="stylesheet" href="/assets/index.css"> <script type="module" src="/assets/index.js"></script> <zug-birdnet></zug-birdnet> ``` No routing. The component is self-contained and can be placed anywhere on the page. Third-party CMS integration (e.g., Contao) only needs to include the built assets and the custom element tag. ## Configuration App-level settings are in `src/config.ts`: | Option | Default | Description | |---|---|---| | `SHOW_DEMO_INFOPOINTS` | `false` | Show static info markers on the map (demo/development only) |

Landkreis Verden, Anlagen nach BImSchG

Anlagen nach dem Bundes-Immissionsschutzgesetz im Landkreis Verden

4.5 million years of deep ocean carbon isotope gradients and trace metals redox data

This dataset contains a 4.5 million year record of the benthic stable carbon isotope gradient between Ocean Drilling Program Sites 982 and 807 and a long trace metals dataset from ODP Site 1208. In addition, we include compiled timeslice data from throughout the deep ocean that characterize the stable carbon isotope difference between benthic stable isotope composition of C. wuellerstorfi at Site 982 and that site.

TOC, TIC, TN and TS contents and stable isotope signatures (δ13C of TOC, δ15N, δ34S) of fine-grained saltmarsh deposits of the barrier island Spiekeroog at the southern North Sea Coast

The dataset compiles total organic carbon (TOC), total inorganic carbon (TIC), total nitrogen (TN) and total sulfur (TS) contents and stable isotope signatures (δ13C of TOC, δ15N, δ34S) of fine-grained deposits (clay, loam) over sandy subsoils of the saltmarsh of the barrier island Spiekeroog at the southern North Sea coast. Sampling was performed in September 2016 along three transects spanning from the high saltmarsh to the pioneer zone. At each sample point, soil samples were taken from the first 5 cm of the upper part (top samples) and from the deepest 5 cm of the lower part (bottom samples) of the fine-grained deposit. If the fine-grained deposit layer had a thickness < 10 cm, only one bulk soil sample (single samples) was taken for the depth range equal to the deposit thickness. Samples were ground to fine powder. TIC was measured on oven-dried samples coulometrically with an Analytik Jena multi EA 4000 analyzer. The total carbon (TC), TN, and TS were analyzed using a Thermo Scientific Flash EA Isolink Elemental Analyzer. The TOC contents were calculated as the difference between TC and TIC. TOC, TN, and TS contents are reported based on the original dry mass. For isotope analysis, dried and homogenized samples were weighed in tin cups and combusted in a Thermo Scientific Flash EA Isolink Elemental Analyzer, connected to a Thermo Finnigan MAT 253 gas mass spectrometer via a Thermo Conflo IV split interface. The δ13C values of TOC were measured after decalcification of the ground powders with p. a. grade HCl. The TN and δ34S analysis were carried out on a separate aliquot of sample powder. The isotope results are given in the conventional δ-notation.

The role of the East Greenland Current in the mid to late Holocene North Atlantic climate variability

Variations in the strength of arctic freshwater export via the East Greenland Current (EGC) can affect thermohaline circulation and the strength of the Subpolar Gyre and, therefore, can modulate the northward heat transport in the North Atlantic Ocean. To assess the role of the EGC in the mid to late Holocene North Atlantic climate variability, its palaeoceanographic history and spatial extent will be studied at three key sites; two sites in the EGC core (Foster Bugt and Nansen Trough) and one site in the Subpolar Front area (SPF; Reykjanes Ridge). For the first time, palaeoceanographic data sets, spanning the last 6000 years, for the EGC core will be produced at a multi-decadal to centennial time scale. A multi-proxy approach, combining foraminifera, diatom, dinoflagellate as well as stable isotope, trace element (Mg/Ca) and IP25 analyses on the same sample set will be performed in close collaboration with national and international project partners. The proposed reconstructions will be linked to marine and terrestrial high-resolution studies from the North Atlantic Drift, the West Greenland Current, the Fram Strait, the Baltic Sea and continental Europe, in order to investigate the timing (in-phase/out-of-phase) of mid to late Holocene climatic oscillations in the different regions. Reconstructing the role of the EGC at high resolution will increase our understanding of trigger mechanisms underlying natural mid to late Holocene climate variability in the North Atlantic region.

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