This is a placeholder page for the MDI TARP (Tracked Active Region Patch) data product.
This data series is a tracked active region catalog covering the era of Michelson Doppler Imager (MDI) synoptic data, 1996–2010. We identified all patches encapsulating active regions (AR) on full-disk MDI imagery and tracked each one across the visible disk. One AR passing across the visible disk is referred to as an MDI Active Region Patch (MARP) and is assigned a MARP number, akin to a NOAA AR number. For most MARPs, the catalog information consists of a time series of about 200 appearances spread across a complete disk passage. We track and combine ARs that appear in separate locations and later merge. Also, we continue to track and consistently group ARs as they decay into separated remnants.
The final MARP catalog contains about 6200 ARs found in 84000 synoptic (96 minute cadence) MDI magnetograms. For each appearance of each AR, we have produced summary statistics including location, latitude/longitude and image-pixel extent, area, and integrated flux. For each appearance, we also produce a region-extent image mask, which is essential for complex ARs, decaying ARs, and nearby but distinct ARs. Where possible, each MARP has been associated with a NOAA AR number. All these parameters are stored in keywords for each AR and for each time.