IMERG V06 Release Notes
The algorithm for the Integrated Multi-satellitE Retrievals for GPM (IMERG) has now been upgraded to Version 06. The transition to V05 for the IMERG Final Run began 13 March 2019 at PPS and the new data started flowing down to the GES DISC as well. However, on 15 March 2019 an error was discovered in processing the initial batches of V06 IMERG Final Run months. A design choice in the code ended up retaining microwave precipitation estimates in the latitude band 60°N-S when there is snow/ice on the surface, rather than masking out the estimates due to low performance in such cases. [Masking for microwave retrievals over surface snow and ice
outside that band is correct.] All then-existent V06A Monthly and Half-hourly IMERG products (June 2014-December 2015) were retracted, and corrected datasets released. The GPM-era Final Run begins on 1 June 2014 to allow a spin-up of calibration files and extends to the (delayed) present. Retrospective processing for the TRMM era Final Run began on 15 April 2019. Due to IR data issues at present, the actual start of the record is June 2000 to allow spin-up of the calibration files. Initial Processing of the Early and Late Runs will begin on 1 May, with Retrospective Processing commencing when the Final Run is fully retrospectively processed. Version 06A supersedes all prior IMERG versions, and users are urged to shift to the new datasets as soon as practical.