Dieses GEDI-Produkt (Global Ecosystem Dynamics Investigation) der Stufe 4B bietet Schätzungen der mittleren oberirdischen Biomasse (AGBD) von 1 km × 1 km basierend auf Beobachtungen aus der Missionswoche 19 (beginnend am 18.04.2019) bis zur Missionswoche 138 (endend am 04.08.2021). Beim GEDI-Produkt „L4A Footprint Biomass“ wird jede hochwertige Wellenform in eine AGBD-Vorhersage umgewandelt. Beim Produkt „L4B“ wird die Stichprobe innerhalb der Grenzen jeder 1-km-Zelle verwendet, um die durchschnittliche AGBD statistisch abzuleiten.
Die GEDI-Mission (Global Ecosystem Dynamics Investigation) zielt darauf ab, die Struktur und Dynamik von Ökosystemen zu charakterisieren, um die Quantifizierung und das Verständnis des Kohlenstoffkreislaufs und der Biodiversität der Erde grundlegend zu verbessern. Das GEDI-Instrument, das an der Internationalen Raumstation (ISS) angebracht ist, erfasst Daten weltweit zwischen 51,6° N und 51,6° S mit der höchsten Auflösung und der dichtesten Stichprobenerhebung der dreidimensionalen Struktur der Erde. Das GEDI-Instrument besteht aus drei Lasern, die insgesamt acht Boden-Transekte erzeugen. Dabei werden acht etwa 25 m große Footprints erfasst, die entlang der Flugbahn in einem Abstand von etwa 60 m angeordnet sind.
Mittlere Biomasse über dem Boden (Einheit): Geschätzte mittlere AGBD für die 1‑km-Rasterzelle, einschließlich Wald und Nichtwald.
V1
Meter
Varianzkomponente 1 (V1): Unsicherheit bei der Schätzung der mittleren Biomasse aufgrund des Feld-zu-GEDI-Modells, das in L4A verwendet wird.
V2
Meter
Varianzkomponente 2 (V2)
Wenn „Mode of Inference“ = 1, ist dies die Unsicherheit aufgrund der GEDI-Stichprobe der 1-km-Zelle.
Wenn „Mode of Inference“ = 2, ist dies die Unsicherheit, die darauf zurückzuführen ist, dass das Modell die Biomasse anhand von Wall-to-Wall-Daten vorhersagt, die mit dem L4A-Footprint-Produkt kalibriert werden.
SE
Mg/ha
Meter
Standardfehler der mittleren Biomasse über dem Boden (SE): Standardfehler der mittleren Schätzung, der Stichproben- und Modellierungsunsicherheit kombiniert.
PE
%
Meter
Standardfehler als Bruchteil des geschätzten mittleren AGBD (PE).
Wenn der Wert über 100 % liegt, werden die Zellenwerte auf 100 gekürzt.
NC
Meter
Anzahl der Cluster (NC): Anzahl der einzelnen GEDI-Bodenmessungen mit mindestens einer hochwertigen Wellenform, die die Rasterzelle schneidet.
NS
Meter
Anzahl der Stichproben (NS): Gesamtzahl der hochwertigen Wellenformen für alle Bodenmessungen innerhalb der Rasterzelle.
QF
Meter
Qualitätskennzeichnung (QF)
0=Außerhalb der GEDI-Domain
1=Landoberfläche
2=Landoberfläche und erfüllt die L1-Anforderung der GEDI-Mission
(Prozentualer Standardfehler <20% oder Standardfehler < 20 Mg ha-1)
PS
Meter
Vorhersageschicht (PS), die durch den funktionellen Pflanzentyp und den Kontinent bestimmt wird. PS ist mit einer Kovarianzmatrix für L4A-Modellparameter verknüpft, die zur Modellfehlervarianz beiträgt (Tabelle 2).
MI
Meter
Interferenzmodus (Mode of Interference, MI): Methode, die für eine bestimmte Zelle verwendet wird.
Bis zum Abschluss der Mission werden nur die Zellen, in denen hybride Inferenz möglich ist, mit einem durchschnittlichen Biomassewert gefüllt.
Dubayah, R.O., J. Armston, S.P. Healey, Z. Yang, P.L. Patterson, S. Saarela,
G. Stahl, L. Duncanson und J.R. Kellner. 2022. GEDI L4B Gridded Aboveground Biomass Density, Version 2. ORNL DAAC, Oak Ridge, Tennessee, USA.
doi:10.3334/ORNLDAAC/2056
Dieses GEDI-Produkt (Global Ecosystem Dynamics Investigation) der Stufe 4B bietet Schätzungen der mittleren Biomasse-Dichte über dem Boden (AGBD) auf einer Fläche von 1 km × 1 km basierend auf Beobachtungen aus der Missionswoche 19 (beginnend am 18.04.2019) bis zur Missionswoche 138 (endend am 04.08.2021). Beim GEDI L4A Footprint Biomass-Produkt wird jede hochwertige Wellenform in … umgewandelt.
[null,null,[],[[["\u003cp\u003eThe LARSE/GEDI/GEDI04_B_002 dataset provides 1 km x 1 km estimates of mean aboveground biomass density (AGBD) from April 18, 2019, to August 4, 2021.\u003c/p\u003e\n"],["\u003cp\u003eThis GEDI L4B product uses high-quality waveforms to predict AGBD and infers mean AGBD within each 1 km grid cell.\u003c/p\u003e\n"],["\u003cp\u003eData is derived from the GEDI mission, which aims to characterize ecosystem structure and dynamics for better understanding of the Earth's carbon cycle and biodiversity.\u003c/p\u003e\n"],["\u003cp\u003eThe dataset includes bands representing mean biomass, standard error, quality flags, and other relevant metrics for analysis.\u003c/p\u003e\n"],["\u003cp\u003eThis dataset is in the public domain and available without restriction on use and distribution, according to NASA's Earth Science Data & Information Policy.\u003c/p\u003e\n"]]],[],null,["# GEDI L4B Gridded Aboveground Biomass Density (Version 2)\n\nDataset Availability\n: 2019-04-18T00:00:00Z--2021-08-04T00:00:00Z\n\nDataset Provider\n:\n\n\n [USFS Laboratory for Applications of Remote Sensing in Ecology (LARSE)](https://www.fs.usda.gov/)\n\n\n [NASA GEDI mission, accessed through the USGS LP DAAC](https://lpdaac.usgs.gov/products/gedi02_av002/)\n\nTags\n:\n[elevation](/earth-engine/datasets/tags/elevation) [forest-biomass](/earth-engine/datasets/tags/forest-biomass) [gedi](/earth-engine/datasets/tags/gedi) [larse](/earth-engine/datasets/tags/larse) [nasa](/earth-engine/datasets/tags/nasa) [tree-cover](/earth-engine/datasets/tags/tree-cover) [usgs](/earth-engine/datasets/tags/usgs) \n\n#### Description\n\nThis Global Ecosystem Dynamics Investigation (GEDI) L4B product provides\n1 km x 1 km estimates of mean aboveground biomass density (AGBD) based on\nobservations from mission week 19 starting on 2019-04-18 to mission\nweek 138 ending on 2021-08-04. The GEDI L4A Footprint Biomass product\nconverts each high-quality waveform to an AGBD prediction, and the\nL4B product uses the sample present within the borders of each 1 km cell to\nstatistically infer mean AGBD.\n\nPlease see [User Guide](https://daac.ornl.gov/GEDI/guides/GEDI_L4B_Gridded_Biomass.html)\nfor more information.\n\nThe Global Ecosystem Dynamics Investigation [GEDI](https://gedi.umd.edu/)\nmission aims to characterize ecosystem structure and dynamics to enable\nradically improved quantification and understanding of the Earth's carbon cycle\nand biodiversity. The GEDI instrument, attached to the International Space\nStation (ISS), collects data globally between 51.6° N and 51.6° S\nlatitudes at the highest resolution and densest sampling of the\n3-dimensional structure of the Earth. The GEDI instrument consists of three\nlasers producing a total of eight beam ground transects, which instantaneously\nsample eight \\~25 m footprints spaced approximately every 60 m along-track.\n\n| Product | Description |\n|--------------------|---------------------------------------------------------------------------------------------------|\n| L2A Vector | [LARSE/GEDI/GEDI02_A_002](/earth-engine/datasets/catalog/LARSE_GEDI_GEDI02_A_002) |\n| L2A Monthly raster | [LARSE/GEDI/GEDI02_A_002_MONTHLY](/earth-engine/datasets/catalog/LARSE_GEDI_GEDI02_A_002_MONTHLY) |\n| L2A table index | [LARSE/GEDI/GEDI02_A_002_INDEX](/earth-engine/datasets/catalog/LARSE_GEDI_GEDI02_A_002_INDEX) |\n| L2B Vector | [LARSE/GEDI/GEDI02_B_002](/earth-engine/datasets/catalog/LARSE_GEDI_GEDI02_B_002) |\n| L2B Monthly raster | [LARSE/GEDI/GEDI02_B_002_MONTHLY](/earth-engine/datasets/catalog/LARSE_GEDI_GEDI02_B_002_MONTHLY) |\n| L2B table index | [LARSE/GEDI/GEDI02_B_002_INDEX](/earth-engine/datasets/catalog/LARSE_GEDI_GEDI02_B_002_INDEX) |\n| L4A Biomass Vector | [LARSE/GEDI/GEDI04_A_002](/earth-engine/datasets/catalog/LARSE_GEDI_GEDI04_A_002) |\n| L4A Monthly raster | [LARSE/GEDI/GEDI04_A_002_MONTHLY](/earth-engine/datasets/catalog/LARSE_GEDI_GEDI04_A_002_MONTHLY) |\n| L4A table index | [LARSE/GEDI/GEDI04_A_002_INDEX](/earth-engine/datasets/catalog/LARSE_GEDI_GEDI04_A_002_INDEX) |\n| L4B Biomass | [LARSE/GEDI/GEDI04_B_002](/earth-engine/datasets/catalog/LARSE_GEDI_GEDI04_B_002) |\n\n### Bands\n\n\n**Pixel Size**\n\n1000 meters\n\n**Bands**\n\n| Name | Units | Pixel Size | Description |\n|------|-------|------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| `MU` | Mg/ha | meters | Mean aboveground biomass density (MU): Estimated mean AGBD for the 1 km grid cell, including forest and non-forest. |\n| `V1` | | meters | Variance component 1 (V1): Uncertainty in the estimate of mean biomass due to the field-to-GEDI model used in L4A. |\n| `V2` | | meters | Variance component 2 (V2) - If Mode of Inference = 1, this is the uncertainty due to GEDI's sampling of the 1 km cell. - If Mode of Inference = 2, this is uncertainty owing to the model predicting biomass using wall-to-wall data, calibrated with the L4A footprint product. |\n| `SE` | Mg/ha | meters | Mean aboveground biomass density standard error (SE): Standard Error of the mean estimate, combining sampling and modeling uncertainty. |\n| `PE` | % | meters | Standard error as a fraction of the estimated mean AGBD (PE). If \\\u003e100%, the cell values are truncated to 100. |\n| `NC` | | meters | Number of clusters (NC): Number of unique GEDI ground tracks with at least one high-quality waveform intersecting the grid cell. |\n| `NS` | | meters | Number of samples (NS): Total number of high-quality waveforms across all ground tracks within the grid cell. |\n| `QF` | | meters | Quality flag (QF) - 0=Outside the GEDI domain - 1=Land surface - 2=Land surface and meets GEDI mission L1 requirement (Percent standard error \\\u003c20% or Standard Error \\\u003c 20 Mg ha-1) |\n| `PS` | | meters | Prediction stratum (PS) determined by plant functional type and continent. PS is associated with an L4A model parameter covariance matrix that contributes to the Model Error Variance (Table 2). |\n| `MI` | | meters | Mode of interference (MI): Method used for a particular cell. Until mission completion, only those cells where hybrid inference is possible will be populated with a mean biomass value. - 0=None applied - 1=Hybrid Model-Based - 2=Generalized Hierarchical Model-Based |\n\n### Terms of Use\n\n**Terms of Use**\n\nThis dataset is in the public domain and is available\nwithout restriction on use and distribution. See [NASA's\nEarth Science Data \\& Information Policy](https://www.earthdata.nasa.gov/engage/open-data-services-and-software/data-and-information-policy)\nfor additional information.\n\n### Citations\n\nCitations:\n\n- Dubayah, R.O., J. Armston, S.P. Healey, Z. Yang, P.L. Patterson, S. Saarela,\n G. Stahl, L. Duncanson, and J.R. Kellner. 2022. GEDI L4B Gridded Aboveground\n Biomass Density, Version 2. ORNL DAAC, Oak Ridge, Tennessee, USA.\n [doi:10.3334/ORNLDAAC/2056](https://doi.org/10.3334/ORNLDAAC/2056)\n\n### DOIs\n\n- \u003chttps://doi.org/10.3334/ORNLDAAC/2056\u003e\n\n### Explore with Earth Engine\n\n| **Important:** Earth Engine is a platform for petabyte-scale scientific analysis and visualization of geospatial datasets, both for public benefit and for business and government users. Earth Engine is free to use for research, education, and nonprofit use. To get started, please [register for Earth Engine access.](https://console.cloud.google.com/earth-engine)\n\n### Code Editor (JavaScript)\n\n```javascript\nvar l4b = ee.Image('LARSE/GEDI/GEDI04_B_002')\n\nMap.addLayer(\n l4b.select('MU'),\n {min: 10, max: 250, palette: '440154,414387,2a788e,23a884,7ad151,fde725'},\n 'Mean Biomass');\nMap.addLayer(\n l4b.select('SE'),\n {min: 10, max: 50, palette: '000004,3b0f6f,8c2981,dd4a69,fe9f6d,fcfdbf'},\n 'Standard Error');\n```\n[Open in Code Editor](https://code.earthengine.google.com/?scriptPath=Examples:Datasets/LARSE/LARSE_GEDI_GEDI04_B_002) \n[GEDI L4B Gridded Aboveground Biomass Density (Version 2)](/earth-engine/datasets/catalog/LARSE_GEDI_GEDI04_B_002) \nThis Global Ecosystem Dynamics Investigation (GEDI) L4B product provides 1 km x 1 km estimates of mean aboveground biomass density (AGBD) based on observations from mission week 19 starting on 2019-04-18 to mission week 138 ending on 2021-08-04. The GEDI L4A Footprint Biomass product converts each high-quality waveform to an ... \nLARSE/GEDI/GEDI04_B_002, elevation,forest-biomass,gedi,larse,nasa,tree-cover,usgs \n2019-04-18T00:00:00Z/2021-08-04T00:00:00Z \n-52 -180 52 180 \nGoogle Earth Engine \nhttps://developers.google.com/earth-engine/datasets\n\n- [https://doi.org/10.3334/ORNLDAAC/2056](https://doi.org/https://www.fs.usda.gov/)\n- [https://doi.org/10.3334/ORNLDAAC/2056](https://doi.org/https://lpdaac.usgs.gov/products/gedi02_av002/)\n- [https://doi.org/10.3334/ORNLDAAC/2056](https://doi.org/https://developers.google.com/earth-engine/datasets/catalog/LARSE_GEDI_GEDI04_B_002)"]]
