RELEASE-2021

Net surface-atmosphere exchange, or “flux” quantifies how much heat, water (H2O) and carbon dioxide (CO2) are transferred between an ecosystem and the atmosphere. Fluxes are useful in a variety scientific applications, including to study ecosystem processes, to interpret and calibrate satellite observations of the earth system, and to constrain ecosystem and earth system models. One of the most direct approaches to observe the net surface-atmosphere exchange is the in-situ [eddy-covariance method](https://youtu.be/CR4Anc8Mkas). Calculation of the net surface-atmosphere exchange involves the estimation of at least two major terms (assuming horizontally homogenous surface conditions): the turbulent flux and the storage flux. In addition, stable isotope measurements of CO2 and H2O within and above the ecosystem canopy can support the subsequent partitioning of the net surface-atmosphere exchange into ecosystem constituent fluxes. For example, partitioning CO2 into photosynthesis and respiration, or evaporation and transpiration in the case of H2O. For data product and algorithm details please see [NEON.DOC.004571](http://data.neonscience.org/documents); in short: this data product bundle contains derived eddy-covariance data products and associated metadata in HDF5 format. Each file contains metadata about the file structure, table formats, and attributes. For more information on using HDF5 files, please visit The HDF Group website at https://www.hdfgroup.org/. Data, quality flags and metrics (qfqm), and uncertainty metrics (ucrt) are currently provided in folders using the following naming convention within the HDF5 file structure: `data_product_level`/`type_of_data_available`/`data_product_abbreviation` (e.g., “dp01/data/soni”). Empty folders within the file structure are being incrementally filled in future publications. The data products embedded in this bundle currently include the following: Data Product | Type of data available | Abbreviation | Temporal Resolution DP1.00002 Single aspirated air temperature | data, qfqm, ucrt | tempAirLvl | 1-min, 30-min DP1.00003 Triple aspirated air temperature | data, qfqm, ucrt | tempAirTop | 1-min, 30-min DP1.00007 3D wind speed, direction and sonic temperature | data, qfqm, ucrt | soni | 1-min, 30-min DP1.00010 3D wind attitude and motion reference | data, qfqm, ucrt | amrs | 1-min, 30-min DP1.00034 CO2 concentration - turbulent | data, qfqm, ucrt | co2Turb | 1-min, 30-min DP1.00035 H2O concentration - turbulent | data, qfqm, ucrt | h2oTurb | 1-min, 30-min DP1.00036 Atmospheric CO2 isotopes | data, qfqm, ucrt | isoCo2 | 9-min, 30-min DP1.00037 Atmospheric H2O isotopes | data, qfqm, ucrt | isoH2o | 9-min, 30-min DP1.00099 CO2 concentration - storage | data, qfqm, ucrt | co2Stor | 2-min, 30-min DP1.00100 H2O concentration - storage | data, qfqm, ucrt | h2oStor | 2-min, 30-min DP2.00008 CO2 concentration rate of change | data, qfqm | co2Stor | 30-min DP2.00009 H2O concentration rate of change | data, qfqm | h2oStor | 30-min DP2.00024 Temperature rate of change | data, qfqm | tempStor | 30-min DP3.00008 Temperature rate of change profile | data, qfqm | tempStor | 30-min DP3.00009 CO2 concentration rate of change profile | data, qfqm | co2Stor | 30-min DP3.00010 H2O concentration rate of change profile | data, qfqm | h2oStor | 30-min DP4.00002 Sensible heat flux | data, qfqm | fluxTemp | 30-min DP4.00007 Momentum flux | data, qfqm | fluxMome | 30-min DP4.00067 Carbon dioxide flux | data, qfqm | fluxCo2 | 30-min DP4.00137 Latent heat flux | data, qfqm | fluxH2o | 30-min DP4.00201 Flux footprint characteristics | data, qfqm | foot | 30-min Latency: Data collected in any given month are published during the second full week of the following month.

地表-大气净交换量（Net surface-atmosphere exchange），或称"通量(flux)"，用于量化生态系统与大气之间热量、水（H₂O）以及二氧化碳（CO₂）的交换量。通量在诸多科学场景中具备应用价值，包括生态系统过程研究、地球系统卫星观测数据的解译与校准，以及约束生态系统和地球系统模型。观测地表-大气净交换量最直接的方法之一是原位涡度协方差法(eddy-covariance method)（详见https://youtu.be/CR4Anc8Mkas）。地表-大气净交换量的计算，在假设地表水平均一的前提下，需至少估算两项核心分量：湍流通量与存储通量。此外，对生态系统冠层内外的CO₂与H₂O进行稳定同位素测量，可辅助后续将地表-大气净交换量拆分为生态系统各组分通量，例如将CO₂通量拆分为光合作用与呼吸作用，针对H₂O则可拆分为蒸发与蒸腾过程。如需了解数据产品与算法的详细信息，请参阅[NEON.DOC.004571](http://data.neonscience.org/documents)；简言之，本数据产品套件包含派生的涡度协方差数据产品及HDF5格式的相关元数据。每个文件均包含有关文件结构、表格格式与属性的元数据。如需了解HDF5文件的使用方法，请访问HDF集团官网：https://www.hdfgroup.org/。当前HDF5文件结构中，数据、质量标志与指标（quality flags and metrics, qfqm）以及不确定性指标（uncertainty metrics, ucrt）将按照以下命名规范存储于对应文件夹：`数据产品层级`/`可用数据类型`/`数据产品缩写`（例如"dp01/data/soni"）。文件结构中的空文件夹将在后续版本发布中逐步补充完整。本套件当前包含以下数据产品：
| 数据产品编号 | 数据名称 | 可用数据类型 | 缩写 | 时间分辨率 |
| ---- | ---- | ---- | ---- | ---- |
| DP1.00002 | 单通道通风空气温度 | data, qfqm, ucrt | tempAirLvl | 1分钟、30分钟 |
| DP1.00003 | 三通道通风空气温度 | data, qfqm, ucrt | tempAirTop | 1分钟、30分钟 |
| DP1.00007 | 三维风速、风向与超声温度 | data, qfqm, ucrt | soni | 1分钟、30分钟 |
| DP1.00010 | 三维风场姿态与运动参考 | data, qfqm, ucrt | amrs | 1分钟、30分钟 |
| DP1.00034 | 湍流二氧化碳浓度 | data, qfqm, ucrt | co2Turb | 1分钟、30分钟 |
| DP1.00035 | 湍流水浓度 | data, qfqm, ucrt | h2oTurb | 1分钟、30分钟 |
| DP1.00036 | 大气二氧化碳同位素 | data, qfqm, ucrt | isoCo2 | 9分钟、30分钟 |
| DP1.00037 | 大气水同位素 | data, qfqm, ucrt | isoH2o | 9分钟、30分钟 |
| DP1.00099 | 存储式二氧化碳浓度 | data, qfqm, ucrt | co2Stor | 2分钟、30分钟 |
| DP1.00100 | 存储式水浓度 | data, qfqm, ucrt | h2oStor | 2分钟、30分钟 |
| DP2.00008 | 二氧化碳浓度变化速率 | data, qfqm | co2Stor | 30分钟 |
| DP2.00009 | 水浓度变化速率 | data, qfqm | h2oStor | 30分钟 |
| DP2.00024 | 温度变化速率 | data, qfqm | tempStor | 30分钟 |
| DP3.00008 | 温度变化速率廓线 | data, qfqm | tempStor | 30分钟 |
| DP3.00009 | 二氧化碳浓度变化速率廓线 | data, qfqm | co2Stor | 30分钟 |
| DP3.00010 | 水浓度变化速率廓线 | data, qfqm | h2oStor | 30分钟 |
| DP4.00002 | 感热通量 | data, qfqm | fluxTemp | 30分钟 |
| DP4.00007 | 动量通量 | data, qfqm | fluxMome | 30分钟 |
| DP4.00067 | 二氧化碳通量 | data, qfqm | fluxCo2 | 30分钟 |
| DP4.00137 | 潜热通量 | data, qfqm | fluxH2o | 30分钟 |
| DP4.00201 | 通量足迹特征 | data, qfqm | foot | 30分钟 |
发布延迟规则：当月采集的数据将于次月的第二个完整工作周内发布。