remotesensing-11-01781-v2.pdf (13.71 MB)
The summertime diurnal cycle of precipitation derived from IMERG
journal contribution
posted on 2019-08-21, 09:13 authored by Daniel Watters, Alessandro BattagliaThe Integrated Multi-satellitE Retrievals for GPM (IMERG) precipitation product derived from the Global Precipitation Measurement (GPM) constellation offers a unique opportunity of observing the diurnal cycle of precipitation in the latitudinal band 60°N-S at unprecedented 0.1° × 0.1° and half-hour resolution. The diurnal cycles of occurrence, intensity and accumulation are determined using four years of data at 2° × 2° resolution; this study focusses on summertime months when the diurnal cycle shows stronger features. Harmonics are fitted to the diurnal cycle using a non-linear least squares method weighted by random errors. Results suggest that mean-to-peak amplitudes for the diurnal cycles of occurrence and accumulation are greater over land (generally larger than 25% of the diurnal mean), where the diurnal harmonic dominates and peaks at ~16-24 LST, than over ocean (generally smaller than 25%), where the diurnal and semi-diurnal harmonics contribute comparably. Over ocean, the diurnal harmonic peaks at ~0-10 LST (~8-15 LST) over open waters (coastal waters). For intensity, amplitudes of the diurnal and semi-diurnal harmonics are generally comparable everywhere (~15-35%) with the diurnal harmonic peaking at ~20-4 LST (~3-12 LST) over land (ocean), and the semi-diurnal harmonic maximises at ~5-8 LST and 17-20 LST. The diurnal cycle of accumulation is dictated by occurrence as opposed to intensity.
Funding
Daniel Watters was funded by a Natural Environment Research Council studentship awarded through the Central England NERC Training Alliance (CENTA; grant reference NE/L002493/1) and by the University of Leicester. The work by A. Battaglia was funded by ESA in the frame of the RAINCAST project (ESA Contract No. 4000125959/18/NL/NA). Acknowledgments: The version-5 level-3 IMERG data were provided by the NASA/Goddard Space Flight Center and PPS, which develop and compute the V05 level–3 IMERG data as a contribution to GPM, and archived at the NASA GES DISC. This research used the SPECTRE High Performance Computing Facility at the University of Leicester.
History
Citation
Remote Sensing, 2019, 11 (15), 1781Author affiliation
/Organisation/COLLEGE OF SCIENCE AND ENGINEERING/Department of Physics and AstronomyVersion
- VoR (Version of Record)