Identified Potential Vorticity Structures associated with African Easterly Waves

<p>This data set contains identified and tracked 3-D Potential Vorticity (PV) structures associated with African Easterly Waves (AEWs), based on the ERA-5 reanalysis of the years 2002-2022 from June to October.</p><p>First the AEW troughs are identified as outlined and separately submitted in <a href="https://zenodo.org/records/8403744">this dataset.</a> To extract the 3-D PV structures in these waves, a Hilbert transform is employed to compute the wave phase at every point in the domain. This yields the trough area of the waves. Within these areas, PV is collected and processed, and assigned a low-dimensional description, including a best-fit ellipsoid for statistical analyses. More details on the methodology can be found in a soon to be submitted publication.</p><p>The JSON files within this dataset provide a description of the PV features, structured as follows:</p><ol><li>Each file contains one year of data, with one set each.</li><li>Each set includes:<ul><li>A list of timestamps, where each timestamp contains the identified troughs at a specific time. Each time entry contains a list of objects (PV features), with each containing a set-unique identifier and properties describing the feature, such as the ellipsoid and a &nbsp;bounding box.</li><li>The data graph, consisting of a list of edges, wherein each edge connects one parent object to multiple child objects, forming the tracking graph. A connection between a parent and child indicates that they represent the same feature entity, with the child being the next manifestation of the parent entity along the time line.</li><li>A list of tracks, with each track represented as a data graph as well.</li></ul></li></ol><p>&nbsp;</p>