EVALUATION OF SATELLITE-DERIVED HIGH RESOLUTION RAINFALL ESTIMATES OVER EASTERN SÃO PAULO AND PARANÁ,, BRAZIL Augusto J. Pereira Filho 1 Phillip Arkin 2 Joe Turk 3 John E. Janowiak 4 Cesar Beneti 5 Leonardo Calvetti 5 Ricardo Hallak 1 Felipe Vemado 1 1 DAC/IAG, University of São Paulo, Brazil 2 ESSIC, University of Maryland, College Park, USA 3 NRL, Marine Meteorology Division, USA 4 Climate Prediction Center/NOAA, USA 5 SIMEPAR, Paraná, Brazil PEHRPP Wokshop, Geneve,, Switzerland 03-05 05 December, 2007
Paraná São Paulo
Background PEHRPP Wokshop, Geneve, Switzerland 03-05 05 December, 2007
HOURLY ACCUMULATION 2003 and 2004 (Pereira Filho et al., 2006) (mm) PEHRPP Wokshop, Geneve, Switzerland 03-05 05 December, 2007
TIME OF MAXIMUM RAINFALL 2003 and 2004 (UTC) (Pereira Filho et al., 2006) (mm) PEHRPP Wokshop, Geneve, Switzerland 03-05 05 December, 2007
RADAR X SATELLITE Total Rainfall (Pereira Filho et al., 2002) 1 = Ground Clutter Filtering (2 and 3) 4 = Grind Clutter Contamination 5 = Range Effect 7 = Signal Processing 3 rd INTERNATIONAL PRECIPITATION WORKING GROUP WORKSHOP 23-27 27 October 2006, Melbourne, Australia
Program for the Evaluation of High Resolution Precipitation Products (PEHRPP) coordinated by ESSIC and NRL. Goal is to compare and to validate these high resolution datasets. PEHRPP Wokshop, Geneve, Switzerland 03-05 05 December, 2007
False alarms Estimated Hits Misses Observed Estimated Contingency Table yes no yes hits misses Observed no false alarms correct negatives (Elbert, 2003)
Probability of detection POD = hits hits + misses False alarm ratio FAR = false alarms hits + false alarms Bias score BIAS = hits + false alarms hits + misses Critical success index CSI = hits hits + misses + false alarms Root mean square error N 1 RMSE= ( E i Oi ) N i = 1 2 Correlation coefficient ρ = ( E ( E E) ( O O) E) 2 ( O O) 2
SPWR RAINFALL ESTIMATES (m) X CMORPH, TRMM, PERSIANN and NRL- BLENDED São Paulo, Brazil. Workshop on the EHRPP Geneve, Switzerland, 03-05 05 December, 2007
SPWR DATASETS: 10/2005 TO 03/2006; SATELLITE PRECIPITATION DATA: 0.25 DEGREE X 3-HOUR; SYSTEM TYPES: COLD FRONT, RAIN BANDS, ORDINARY CONVECTION, SQUALL LINES PEHRPP Wokshop, Geneve, Switzerland 03-05 05 December, 2007
EXAMPLES PEHRPP Wokshop, Geneve, Switzerland 03-05 05 December, 2007
COLD FRONT Workshop on the EHRPP Geneve, Switzerland, 03-05 05 December, 2007
RAIN BANDS PEHRPP Wokshop, Geneve, Switzerland 03-05 05 December, 2007
ORDINARY CONVECTION 3 rd INTERNATIONAL PRECIPITATION WORKING GROUP WORKSHOP 23-27 27 October 2006, Melbourne, Australia
0,2 OVERALL RESULTS All data sets available 10/05 to 03/06 0,1 mm 0,15 Mean CSI 0,1 0,2 mm 1,0 mm 4,0 mm 0,05 TRMM CMORPH PERSIANN NRL-B PEHRPP Wokshop, Geneve, Switzerland 03-05 05 December, 2007
DISCUSSION (SP) Coordinate discrepancies; Phase and amplitude errors; All four methods yielded poor results; Radar rainfall accumulation higher than satellite ones; Radar data with range effect and other problems; Best performance for low rainfall accumulation: CMORPH; Best performance for higher accumulation: PERSIANN; Fewer data for PERSIANN; All methods are limited; Need for rain gauges and stream gauges verification. PEHRPP Wokshop, Geneve, Switzerland 03-05 05 December, 2007
PARANA STATE Satellite techniques: CMORPH (Joyce et. al., 2004), PERSIANN (Sorooshian et al., 2000), TRMM (Huffman et. al., 1997), NRLB (Turk et. al., 2003) and CST (Adler e Negri, 1998). Data Methodology 141 weather stations over Parana State 1) Observed and estimated rainfall @ 0.25 spatial resolution over 56 W 46.75 W and 27 S-21.75 S for 1 day to a month accumulation. 2)Period: January 2003 December 2005 3)Rain/non-rain threshold: 0.3mm/day and 20mm/month; 4)Statistics: average, variance, bias, POD FAR, ETS, MSE, correlation coefficient; 5)Hovmoller diagrams. PEHRPP Wokshop, Geneve, Switzerland 03-05 05 December, 2007
Hovmöller Diagrams GAUGE CMORPH TRMM mm/month mm/month mm/month PERSIANN NRLB CST mm/month mm/month mm/month
Monthly Accumulation GAUGE October 2005 NRLB CST mm/month NRLB CST BIAS 0.99 1.00 POD 0.99 1.00 FAR 0.00 0.00 COR 0.67 0.62 RMSE 130.40 79.86 GAUGE AVE 245.42 245.42 SAT AVE 123.80 182.25 GAUGE VAR 59.71 59.71 SAT VAR 54.88 50.48 Observed mm/month NRLB rain non-rain rain 546 0 non-rain 1 0 Observed CST rain non-rain rain 552 0 non-rain 0 0 Estimated Estimated mm/month Observed TRMM rain non-rain rain 522 0 non-rain 28 0 Estimated GAUGE May 2005 TRMM TRMM BIAS 0.95 POD 0.95 FAR 0.00 COR 0.79 RMSE 104.02 GAUGE AVE 136.22 SAT AVE 52.98 GAUGE VAR 74.39 SAT VAR 23.85 mm/month mm/month
Monthly Accumulations - Spatial BIAS (Jan/2003 - Dec/2005)
Daily Accumulation November 17th, 2003 CMORPH BIAS 1.05 POD 0.99 FAR 0.05 COR 0.64 RMSE 20.40 GAUGE AVE 32.05 SAT AVE 16.43 GAUGE VAR 17.41 SAT VAR 8.59 Observed CMORPH rain non-rain rain 518 29 non-rain 3 0 Estimated May 12th, 2004 TRMM BIAS 0.99 POD 0.96 FAR 0.03 COR 0.75 RMSE 14.88 GAUGE AVE 25.76 SAT AVE 18.93 GAUGE VAR 19.30 SAT VAR 17.12 Observed TRMM rain non-rain rain 424 13 non-rain 19 84 Estimated
Discussion (PR) Hovmöller diagrams indicate good agreement between satellite-derived estimates and gauges, though amplitude differences are significant. Monthly satellite-derived accumulations better for January, May and October. Daily values highly variable. PEHRPP Wokshop, Geneve, Switzerland 03-05 05 December, 2007
Polarimetric Data Sets 3 rd INTERNATIONAL PRECIPITATION WORKING GROUP WORKSHOP 23-27 27 October 2006, Melbourne, Australia
Mobile Weather Radar Doppler Dual X-band (MXPOL) Hydrometeorology Lab (LabHidro) Institute of Astronomy, Geophysics and Atmospheric Sciences (IAG), University of São Paulo.
Z h V r W ρo hv K dp MXPOL 4,5 o PPI at 2119 UTC on 26 April 2007.
São Paulo City sounding (83779) at 1200 UTC on 22 May 2007. SPWR 3-km CAPPI 1-km x 1-km resolution at 1616 UTC on 22 May 2007. MXPOL at (23 o 33.4 S; 46 o 44.1 W).
Vertical profile - Z h Vertical profile - V r Vertical profile - W MXPOL vertical profiles at 1616 UTC on 22 May 2007. Full clockwise antenna scan (6.0 o s -1 ) @ 90 o, pulse width = 0.2 μs, PRF=1000 Hz and 256 samples, Δz=35m.
Vertical profile - Z dr Vertical profile - φ dp Vertical profile - K dp Vertical profile - ρo hv MXPOL vertical profiles at 1616 UTC on 22 May 2007. Full clockwise antenna scan (6.0 o s -1 ) @ 90 o, pulse width = 0.2 μs, PRF=1000 Hz and 256 samples, Δz=35m.
Work supported by: FAPESP and CNPq (BRAZIL) NCAR and ESSIC (USA) WMO THE END PEHRPP Wokshop, Geneve,, Switzerland 03-05 05 December, 2007