이 데이터 세트는 MethaneAIR 이미징 분광계에서 관측한 대기 중 메탄의 총 기둥 건조 공기 몰 분율 'XCH4'에 대한 지리 공간 데이터를 제공합니다. XCH4는 메탄('CH4')의 총 기둥 양(분자 수)을 공중 분광계에서 지표면까지의 시선과 다시 태양까지의 시선을 따라 공기의 총량 (분자 수, 수증기 양 제외)으로 나눈 값으로 정의됩니다.
참고용으로 추가 데이터 레이어가 제공됩니다. 1622nm에서의 관측된 알베도, 지표면 기압, 지형 높이입니다.
메탄은 대기에 도달한 후 처음 20년 동안 이산화탄소보다 80배 이상 강력한 온실가스입니다. 오늘날 지구 온난화의 최소 30% 는 인간의 행동에서 비롯된 메탄에 의해 발생합니다.
인간 활동과 관련된 메탄 배출량(석유 및 가스 작업, 농업, 폐기물 관리에서 발생하는 피할 수 있는 배출량 포함)을 줄이는 것이 지구 온난화 속도를 늦추는 가장 빠른 방법입니다.
항공기는 11.5~13km (37,000~43,000피트) 고도에서 비행했으며, 초당 10프레임을 획득하고 4.5~4.8km의 스와스, 25도의 시야, 트랙 전체에 걸쳐 896픽셀을 획득하여 트랙을 따라 약 25m, 트랙 전체에 걸쳐 5m의 네이티브 픽셀 크기를 제공했습니다. 분광 데이터는 트랙 전체에서 5개씩 집계되어 평균 픽셀 크기가 25m x 25m입니다. 농도 (XCH4)는 이러한 고해상도 (0.1nm 샘플링, 0.3nm 해상도)의 공간적으로 분포된 스펙트럼 (Chan Miller et al. (2024))에서 가져온 후 0.0001 x 0.0001도 그리드 (미국에서 약 10m x 8m)에 그리딩됩니다. 격자 데이터의 정밀도는 10억 분의 25 (1s, 약 1.3%)이며 공간 상관 길이 (1/e)는 약 70m입니다. 운영 조건, 시야각, 지표 반사율에 따라 비행마다 약간의 차이가 있습니다.
비행 패턴은 일반적으로 2~3시간 간격으로 약 70km x 100km의 지역을 커버하기 위해 챔보니 패턴의 일련의 타원형 스와스였습니다. 여기 표시된 데이터는 비행 트랙이 겹치는 부분에서 평균화됩니다. 일반적으로 각 스와스의 가장자리와 잼보니 패턴의 상단 및 하단에 있는 urn에서 평균화됩니다.
이 데이터 세트는 2021년 7월 30일과 2023년 10월 13일 사이에 항공편에서 측정한 MethaneAIR 측정값을 사용하여 생성되었습니다. MethaneAIR는 Environmental Defense Fund의 전액 출자 자회사인 MethaneSAT LLC가 관리하는 MethaneSAT 위성 임무의 항공 전구체입니다. 메탄 배출 플럭스는 이러한 각 Zamboni 스와스에서 지리 통계 역 모델링 프레임워크를 사용하여 생성되었습니다.
Chan Miller, C., Roche, S., Wilzewski, J. S., Liu, X., Chance, K., Souri,
A. H., Conway, E., Luo, B., Samra, J., Hawthorne, J., Sun, K., Staebell, C.,
Chulakadabba, A., Sargent, M., Benmergui, J. S., Franklin, J. E., Daube, B.
C., 리, Y., Laughner, J. L., Baier, B. C., Gautam, R., Omara, M., and Wofsy,
S. C. 2023. CO2 프록시 접근법을 사용한 MethaneAIR의 메탄 검색: 예정된 MethaneSAT 미션의 데모, EGUsphere [사전 인쇄].
doi:10.5194/egusphere-2023-19623,
[null,null,[],[[["\u003cp\u003eThe EDF/MethaneSAT/MethaneAIR/L3concentration dataset provides geospatial data for the total column dry air mole fraction of methane in the atmosphere ("XCH4") as observed by the MethaneAIR imaging spectrometer.\u003c/p\u003e\n"],["\u003cp\u003eMethaneAIR is an airborne precursor to the MethaneSAT satellite mission, flown at high altitudes to acquire atmospheric methane data with a spatial resolution of approximately 25m x 25m.\u003c/p\u003e\n"],["\u003cp\u003eThe dataset covers the period from July 30, 2021, to October 13, 2023, and includes data layers for XCH4, observed albedo, surface pressure, and terrain height.\u003c/p\u003e\n"],["\u003cp\u003eData is provided by the Environmental Defense Fund and is subject to the MethaneSAT Content License Terms of Use.\u003c/p\u003e\n"],["\u003cp\u003eUsers can explore this dataset and analyze it further using Google Earth Engine.\u003c/p\u003e\n"]]],["The dataset from Environmental Defense Fund's MethaneSAT provides \"XCH4,\" the atmospheric methane concentration, captured by the MethaneAIR spectrometer between August 6, 2021, and October 14, 2023. Data, gridded to approximately 10m x 8m resolution, also include observed albedo, surface pressure, and terrain height. Flights were conducted at high altitudes, using a Zamboni pattern to cover large areas, and data from overlapping tracks are averaged. The data can be accessed using Earth Engine, providing code examples for visualization and analysis.\n"],null,["# MethaneAIR L3 Concentration v1\n\nDataset Availability\n: 2021-08-06T00:00:00Z--2023-10-14T00:00:00Z\n\nDataset Provider\n:\n\n\n [Environmental Defense Fund - MethaneSAT](https://methanesat.org)\n\nTags\n:\n[atmosphere](/earth-engine/datasets/tags/atmosphere) [climate](/earth-engine/datasets/tags/climate) [edf](/earth-engine/datasets/tags/edf) [emissions](/earth-engine/datasets/tags/emissions) [ghg](/earth-engine/datasets/tags/ghg) [methane](/earth-engine/datasets/tags/methane) [methaneair](/earth-engine/datasets/tags/methaneair) [methanesat](/earth-engine/datasets/tags/methanesat) \n\n#### Description\n\nThis dataset provides geospatial data for the total column dry air mole\nfraction of methane in the atmosphere, \"XCH4\", as observed by the MethaneAIR\nimaging spectrometer. XCH4 is defined as the total column amount (number of\nmolecules) of methane (\"CH4\") divided by the total amount of air (number of\nmolecules, water vapor amount removed) along the line of sight from the\nairborne spectrometer to the earth's surface and back up to the sun.\nAdditional data layers are provided for reference: observed albedo at 1622\nnm, surface pressure, and terrain height.\n\nMethane is a potent greenhouse gas that has more than 80 times the warming power\nof carbon dioxide over the first 20 years after it reaches the atmosphere. At\nleast 30% of today's global warming is driven by methane from human actions.\nCutting methane emissions associated with human activities - including avoidable\nemissions from oil and gas operations, agriculture, and waste management - is\nthe single fastest way to slow the rate of global warming.\n\nThe aircraft was flown at 11.5 - 13 km altitude (37,000 - 43,000 feet),\nacquiring 10 frames per second with a swath of 4.5 - 4.8 km with a 25 degree\nfield of view and 896 pixels across track, giving a native pixel size at\nnadir of approximately 25m along track and 5 m across track. The\nspectroscopic data are aggregated by 5 across track, giving a mean pixel\nsize of 25m x 25m. Concentrations (XCH4) are retrieved from these high\nresolution (0.1 nm sampling, 0.3nm resolution), spatially distributed\nspectra ([Chan Miller et al. (2024)](https://doi.org/10.5194/egusphere-2023-1962)),\nthen gridded on a 0.0001 x 0.0001 degree grid (approximately 10m x 8m over\nthe US). The precision of the gridded data is approximately 25 parts per\nbillion (1s, about 1.3%), and a spatial correlation length (1/e) of about\n70m. There are some variations from flight-to-flight according to operating\nconditions, look angle and surface albedo.\n\nThe flight pattern was typically a series of oval swaths in a Zamboni\npattern to cover a region, typically about 70 km x 100 km, over a 2 - 3 hour\ninterval. The data presented here are averaged where flight tracks overlap,\ntypically at the edges of each swath and in the urns at the top and bottom\nof the Zamboni pattern.\n\nThis dataset was generated using MethaneAIR measurements taken on flights\nbetween 30 July 2021 and 13 October 2023. MethaneAIR is an airborne precursor of\nthe MethaneSAT satellite mission, managed by [MethaneSAT LLC](https://www.methanesat.org/),\na wholly owned subsidiary of Environmental Defense Fund. Methane emission fluxes were produced using a geostatistical inverse\nmodeling framework on each of these Zamboni swaths.\n\nFor additional information about the MethaneAIR instrument, instrument\ncalibration and emission detections, please refer to recent publications by\n[Loughner et al. (2021)](https://doi.org/10.1175/JAMC-D-20-0158.1),\n[Staebell et al. (2021)](https://doi.org/10.5194/amt-14-3737-2021),\n[Conway et al. (2023)](https://doi.org/10.5194/amt-2023-111),\n[Chulakadabba et al. (2023)](https://doi.org/10.5194/egusphere-2023-822),\n[Abbadi et al. (2023)](https://doi.org/10.31223/X51D4C),\n[Omara et al. (2023)](https://doi.org/10.5194/essd-15-3761-2023),\nand [Miller et al. (2023)](https://doi.org/10.5194/egusphere-2023-1962).\n\nContact the data provider for more information about the project at this\nlink: \u003chttps://www.methanesat.org/contact/\u003e\n\n### Bands\n\n\n**Pixel Size**\n\n10.2 meters\n\n**Bands**\n\n| Name | Units | Min | Max | Pixel Size | Description |\n|--------------------|-------|----------|-----------|------------|---------------------------------------------------------------------------|\n| `XCH4` | ppb | 1894\\* | 2114.65\\* | meters | Retrieved column-averaged dry-air CH4 mole fraction. |\n| `albedo` | | 0 | 1 | meters | Ratio of solar radiance at the ground to observed radiance at the sensor. |\n| `surface_pressure` | hPa | 725.95\\* | 1011.33\\* | meters | Air pressure at the surface. |\n| `terrain_height` | km | 0.026\\* | 2.915\\* | meters | Elevation with respect to WGS84 reference ellipsoid. |\n\n\\* estimated min or max value\n\n### Image Properties\n\n**Image Properties**\n\n| Name | Type | Description |\n|---------------------|--------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| flight_id | STRING | Research flight number. |\n| basin | STRING | Oil and Gas basin (e.g. Permian) or area of interest (e.g. New York City). |\n| time_coverage_start | STRING | Data collection start time in YYYY-MM-DDThh:mm:ssZ format STRING (ISO 8601). |\n| time_coverage_end | STRING | Data collection end time in YYYY-MM-DDThh:mm:ssZ format STRING (ISO 8601). |\n| processing_id | STRING | (internal) Processing run identifier that represents the calculations that led to the features. It is not an attribute describing the flight, but the processing pipeline. |\n\n### Terms of Use\n\n**Terms of Use**\n\nUse of this data is subject to [MethaneSAT's Content License Terms of\nUse](https://www.methanesat.org/sites/default/files/2025-02/MethaneSAT%20-%20Content%20License%20Terms%20of%20Use%20%28Revised%202-12-2025%29%5B25%5D.pdf).\n\n### Citations\n\nCitations:\n\n- Chan Miller, C., Roche, S., Wilzewski, J. S., Liu, X., Chance, K., Souri,\n A. H., Conway, E., Luo, B., Samra, J., Hawthorne, J., Sun, K., Staebell, C.,\n Chulakadabba, A., Sargent, M., Benmergui, J. S., Franklin, J. E., Daube, B.\n C., Li, Y., Laughner, J. L., Baier, B. C., Gautam, R., Omara, M., and Wofsy,\n S. C. 2023. Methane retrieval from MethaneAIR using the CO2 Proxy Approach:\n A demonstration for the upcoming MethaneSAT mission, EGUsphere \\[preprint\\].\n [doi:10.5194/egusphere-2023-19623](https://doi.org/10.5194/egusphere-2023-1962),\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 dataset = ee.ImageCollection(\"EDF/MethaneSAT/MethaneAIR/L3concentration\");\n\nvar fluxVisParams = {\n bands: ['XCH4'],\n min: 1870,\n max: 2030,\n palette: ['#070088','#a3069b','#cc4e64','#ffa826','#edfb59'],\n};\n\n// Center on one of the available areas of interests.\nMap.setCenter(-102.9, 32, 8);\nMap.addLayer(dataset, fluxVisParams, 'Retrieved column-averaged dry-air CH4 mole fraction');\n```\n[Open in Code Editor](https://code.earthengine.google.com/?scriptPath=Examples:Datasets/EDF/EDF_MethaneSAT_MethaneAIR_L3concentration) \n[MethaneAIR L3 Concentration v1](/earth-engine/datasets/catalog/EDF_MethaneSAT_MethaneAIR_L3concentration) \nThis dataset provides geospatial data for the total column dry air mole fraction of methane in the atmosphere, \"XCH4\", as observed by the MethaneAIR imaging spectrometer. XCH4 is defined as the total column amount (number of molecules) of methane (\"CH4\") divided by the total amount of air (number of molecules, ... \nEDF/MethaneSAT/MethaneAIR/L3concentration, atmosphere,climate,edf,emissions,ghg,methane,methaneair,methanesat \n2021-08-06T00:00:00Z/2023-10-14T00:00:00Z \n27.62 -118.42 54.6 -73.44 \nGoogle Earth Engine \nhttps://developers.google.com/earth-engine/datasets\n\n- [](https://doi.org/https://methanesat.org)\n- [](https://doi.org/https://developers.google.com/earth-engine/datasets/catalog/EDF_MethaneSAT_MethaneAIR_L3concentration)"]]
