Why publish your layers via OpenLandMap.org?
Have you just published a paper which has also resulted in the production of a global (environmental) layer(s) that is of potential importance for a wider audience? Are your data <100GB in size (after compression) and are you willing to release it under some form of Open Data license? If Yes: then please consider submitting your data for publication / hosting at LandGIS.
Why publish your layers via OpenLandMap.org?
- You can reach bigger audience: you will make your data available through a professional web-mapping service (running 100% on Open Source software) which includes: Geoserver, Geonode, OGC standards and REST services.
- You can visualize geographical patterns more efficiently: you can use the LandGIS bookmarking system to communicate discoveries, provide proofs of theories, discuss issues and raise public awareness.
- You will contribute to a higher goal: with LandGIS we especially support projects aimed at land restoration, combating climate change, nature conservation, optimizing land use and education.
- You can leave the hosting to us: if approved for publication, hosting costs will be covered by the OpenGeoHub foundation. We may, however, request that you contribute towards additional costs if your data volumes exceed standard sizes and require additional services.
General requirements
As a general consideration OpenGeoHub requires that any data to be published via OpenLandMap.org satisfies some minimum quality and metadata requirements before it can be accepted to be hosted via our service. The following five primary requirements need to be satisfied before a layer can be considered for inclusion:
- Global coverage with at least 98% of the land mask represented in the layer (as not-NA values).
- An Open Data license.
- Metadata is supplied following the format specified below (all columns are filled-in and up-to-date).
- Sufficient technical documentation is supplied — usually as a scientific paper or a report.
- A GDAL/proj4-compatible data format and projection system is used that allows for inclusion into Geoserver or similar.
Not a requirement, but also highly recommended (this often significantly speeds up inclusion of layers into LandGIS) conditions:
- A peer-reviewed publication exists that describes methodological steps used to produce the layer.
- A public code repository exists that shows all processing steps and is used to collect feedback on code bugs and errors.
- The applicants have a proven capacity to maintain the layers (version control) and provide support. This is often connected with a permanent job position and/or official support within an organization or similar.
- 100% of the land mask represented in the layer.
- Layer prepared as cloud-optimized GeoTIFF.
- File naming convention followed closely.
- Copy of the files uploaded to some public repository (e.g. zenodo.org) and data license and DOI registered.
- Metadata completed and contains live links to project homepage, code repository, data DOI and contacts.
- Layer version consistent with the status of the peer-review publication.
- Styling sheet (SLD file) prepared and optimized for usage in Geoserver.
Preparing a cloud-optimized GeoTiff
An important requirement for a layer to be included in OpenLandMap.org is that it is in a format optimized for distribution / web-mapping. Cloud-optimized GeoTIFF implies that:
- Data is internally compressed so that upload / download is optimized.
- Data is optimized for visualization inside Geoserver.
- Data is optimized (maximum speed) for spatial queries.
Read more about how to prepare a Cloud-optimized GeoTIFF.
Preparing metadata
For each layer or group of layers the following minimum metadata is required.
Table: Metadata columns required during the submission.
Metadata column | Description | Example |
layer_unique_number | Unique number that is used inside LandGIS. Will be assigned by the developers. | 1.1 |
layer_distribution_folder | Folders are separated based on the field resolution e.g. 1km, 250m or similar. | layers250m |
layer_filename_pattern | Filename or filename pattern that will be used to search or subset layers. | dtm_slope_merit.dem_m_250m_s0..0cm_2017_v1.0.tif |
layer_filename_shortname | Short name without time interval or version. Usually generated automatically or is assigned by the developers. | dtm_slope_merit.dem_m |
layer_filename_sld | Styled Layer Descriptor (SLD) file name. | dtm_slope_merit.dem_m.sld |
variable_generic_name | Human-readable variable name. | slope |
layer_display_type | Layer display type e.g. numeric, factor, time-series or seasonal data. Will be assigned by the developers. | 2D_N |
layer_theme | One of the general themes. Will be adjusted by the developers. | dtm |
layer_title | Short (200 letters) title. | Slope in radians |
layer_title_description | Short (2–3 sentences) description of the layer. | Based on the MERIT DEM (Yamazaki et al. 2017) derived using SAGA GIS and Equi7 grid system. |
layer_units | Physical units and correction factor where necessary. | radians |
layer_derivation_url | Live link to the code repository or project page where derivation of the layer is explained in detail. | https://github.com/Envirometrix/ |
layer_description_url | Live link to the code repository or project page with full description of the layer. | https://github.com/Envirometrix/ |
layer_organization | Organization copyright holder. | EnvirometriX Ltd |
layer_contact | Contact person inside the organization. | |
layer_contact_email | Contact person email. | |
layer_data_license | Data license title. | Creative Commons Attribution Share-Alike 4.0 |
layer_data_license_url | Data license URL. | |
layer_citation_date | Production date (when was it submitted to a public repository / when was the DOI generated?) | 05-October-2018 |
layer_citation_title | If a publication is attached to the layer provide a title of the publication. Otherwise provide a title of the layer. | Global DEM derivatives at 250 m, 1 km and 2 km based on the MERIT DEM |
layer_citation_doi | If a publication is attached to the layer provide DOI of the publication and/or DOI of the layer. | 10.5281/zenodo.1447209 |
layer_download_url | Live link from which users can download the complete layer. | |
layer_metadata_url | Live link from which users can access metadata. Will be assigned by the developers. | https://maps.opengeohub.org/layers/ |
Summary points
OpenLandMap.org is a system for discovery, publication and distribution of global environmental layers. It is a web-mapping platform that aspires to be recognized as a kind of “OpenStreetMap for land-related environmental data”. As such, it promotes publication of Open Data and principles of reproducible research.
To submit a global GeoTIFF for hosting on LandGIS please follow these steps:
- Publish the layer production process in some peer-reviewed journal (optional but highly recommended). If the paper has not yet been peer-reviewed / accepted for publication it will come with a specific disclaimer.
- Make sure your layer covers most of the land mask (i.e. that it is as complete as possible).
- Convert your layer to a GeoTIFF. Use one of the standard resolutions and the bounding box.
- Run gdal_translate and add internal compression and tiling (Cloud-optimized GeoTIFF) following these instructions.
- Use the recommended file naming convention (human-readable file names).
- Upload the cloud optimized / internally compressed GeoTIFF to a public repository and set a license and obtain a DOI.
- Fill in the submission form.
- (Optional) send an e-mail to the OpenGeoHub Review Committee (support@opengeohub.org)
Once we approve your application you will receive detailed steps explaining next steps.
Good practices:
- Focus first on documenting the methodology used to produce the layers you would like to publish via LandGIS (send the work for peer-review),
- Follow closely the instructions and requirements,
- Send email only AFTER you have filled in the application form.
Types of maps that will NOT be considered:
- Incomplete, undocumented and not strictly following all submission instructions,
- Proprietary maps or maps distributed under the non-Open / restrictive Non-Commercial licenses (at least justify why you are not allowed to share your data using one of the Open Data licenses),
- Previously copyrighted materials that can not be put under one or more of the recognized Open Data licenses,
- Containing false information or serious flaws