Rainfall Type Estimation from the Information on Life Stage of Deep Convection (Feasibility of assigning the life stage of deep convection) Toshiro Inoue, Daniel Vila* and Tomoo Ushio** Meteorological Research Institute, Tsukuba, Ibaraki, Japan * INA, Buenos Aires, Argentina ** Osaka Prefecture Univ., Osaka, Japan

Motivation IR rainfall estimation is less physical than PMW and PR rainfall estimation. Because IR observes just cloud instead of rain. Advantage of the IR is high temporal observation from geostationary orbit. If we can define the life stage by tracking the deep convection using high temporal observations from geostationary satellite. Then, we might use the information on the life cycle of deep convection for rainfall estimation.

DevelopingMatureDecaying convective rainstratiform rain

TYPE:1 Con. ; TYPE:2 Strat. Rainfall Rate at 2Km observed by PR/TRMM ~1 mm/h ~8 mm/h

TBB-BTD Characteristics for Ice (Function of effective radius and optical thickness) TBB BTD Effective Radius Ci-Dense Cu/Sc Ci-Thin Ci-Thick Cb

MSG-IR MSG-VIS MSG-BTD Split Window Larger BTD-white Smaller BTD-black

Data GOES-W,E 0.1*0.1 Lat/Lon Grid Hourly Split Window Over Eastern Pacific, South America MSG(Meteosat-8) 0.05*0.05 Lat/Lon Grid 15 minutes Split Window Over Africa 253K Ci BTD>1 Cb BTD<1 Cloud type (Cb, Ci) classified by the BTD within 253K cloud area. Definition of Deep Convection

T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 T11 T12 Cloud Type Map Classified by the Split Window 15 minutes interval taken by Meteosat-8 The deep convection starts from 17:45 UTC on 24 May, 2003 to 20:35 UTC on May 24, 2003.

Cloud Type Map Classified by the Split Window GOES-W 2 hourly from 12UTC May 09, °1°

Time Evolution of Deep Convection Cloud number of Cb (blue) and Ci (green) within 253K cloud area.

Evolution of Percentage of Cb and Ci within DC The life time is short in left case, while the life time is longer in right case.

Time evolution of size (top) and % of Ci (bottom)

Cloud Type Map Percentage of convective Rain by PR 2°

Evolution of Cb and Ci Convective-rain>50% Convective-rain<50% 1°1°

Summary The percentage of Ci classified by the split window within 253K cloud is a good indicator to tell the life stage for simple deep convection case from single snap shot image. We could assign different rainfall rate for the same TBB depending on the life stage.

VIS and BTD

VIS BTD87-11 BTD11-12 IR

Time evolution of size (top) and # of Ci (bottom)