GHG Europe Database

Data Access Guideline

To access the database and request to download data it is needed to register and obtain an account. The registration is free and require only few information but it is important to increase security levels, to inform data owner about accesses to their measurements and uses planes and to inform users about new version of the data. To request an account please visit the Registration page.

The data are available to the users according with different data access and data use policies that are often site and year specific and decided by the project and/or the data owner. The data access can be 1) open (the file is prepared and sent to the user immediately after the request) or 2) restricted. In this case (often applied to recent data), if the user has not rights to access directly the data (e.g. when is a partner of the project that funded the data collection) the data access request is automatically sent to the site Principal Investigator (PI) of the site that decides to authorize or not the download.

It is also important to remark that in the data policy organization data access and data use are regulated separately. More information about the data access and data use policy are available in the specific page under Data (bar menu above). Data use policy is also automatically attached to the data downloaded.

Data request steps

Data can be requested using the Data-Request page accessible also from the main menu. The procedure includes few steps:

  1. Log-in using your account or register to obtain an account.

  2. Select the variables of interest. The variables available are also listed in the Guidelines-Obtaining data-Available variables page and it is possible to use the filters in the table header to find the variables of interest and select them for the query. Some of the variables are available in different processing levels:

    • Level 2 data: data provided by the PIs, half-hourly, not gap-filled or filtered but quality checked by the PIs.

    • Level 3 data: obtained from the level 2 products, data are quality checked using standardized techniques and NEE is calculated. Data are not changed but flags are added.

    • Level 4 data: obtained from the level 3 products, data are QAQC filtered, gap-filled and partitioned. Datasets are also aggregated from daily to monthly. Flags with information regarding quality of the original and gap-filled data are added.

    • Ancillary data: Include all the not continuous data that are submitted to the database (e.g. soil properties, biomass, disturbances etc.)

  3. Select the sites of interest. The list of sites and related main information are also available in the Sites section. Here it is also possible to select only sites with opened data access and data use policies.

  4. Select the data range using the calendar or with format dd/mm/yyyy

  5. Press the Check data button to have an overview of the availability of the variables/products requested for the sites selected so that is possible to refine the query

  6. Specify the planned data use to inform the PIs. Please note that this information is mainly used to give access to the data with restricted data access policy

  7. Specify the email where the links to download the data must be send and finalize the request. After this step no other actions are requested.

After the data access request submission, the data shared under an open access policy and so immediately available to the users are prepared and sent to the user by email. For dataset with restricted access the authorization request is automatically sent to the PI.

Versioning system

Each dataset in the Database is identified by a code summarizing the most important information such as data type, site, year, product level and version.

This code will identify univocally the dataset used so that it will be possible to track back the exact data used in the analysis. Data improvement, new submission, reprocessing, added variables etc. will automatically involve a new code generation with a different versioning number and the description of the differences from the previous versions of the dataset. The version codes are added to the datasets when downloaded.

This is the scheme of the versioning code used:

A fist version of the level 2 product with Eddy data from the Collelongo site, year 2003 will have as versioning code:

EFDC_EC_L2_Flx_ITCol_2003_v01

If the PI will send a reprocessed version of one variable (e.g. ustar) than a new code will be generated:

EFDC_EC_L2_Flx_ITCol_2003_v02

A text file will be also generated reporting the description of the changes from the previous version.