MIRS F16 Rainfall Rate Overview and Validation

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MIRS F16 Rainfall Rate Overview and Validation

• F. Iturbide-Sanchez, K. Garrett, C. Grassotti, W.
  Chen, and S.-A. Boukabara

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Outline

• MIRS Rainfall Rate Validation with TRMM
  Precipitation Radar-Based (TRMM-2B31) Product.
• a. F16 Rainfall Rate
• MIRS Rainfall Rate Validation with CPC
  Precipitation.
• a. Daily Composite Precipitation Estimate
• b. F16 Daily Precipitation Estimate

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F16 Rainfall Rate Compared to N18 Rainfall Rate
MIRS F16 Rainfall Rate
MIRS N18 Rainfall Rate
Same regression algorithm (based on MSPPS) is
used to derive F16 and N18 rainfall rate. Main
differences are due to the different temporal and
spatial coverage.
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F16 and N18 Rainfall Rate Compared to TRMM-2B31
Rainfall Rate Over Land 1/2
F16 rainfall rate has shown comparable
correlation, bias and standard deviation to N18
rainfall rate when compared to TRMM-2B31
Rainfall Rate over Land.
Corr0.6601 nPts7447 Bias-0.0066 Stdv0.5317
Corr0.5466 nPts12774 Bias-0.0375 Stdv0.46872
TRMM-2B31 Rainfall Rate (mm/hr)
F16 Rainfall Rate (mm/hr)
N18 Rainfall Rate (mm/hr)
Comparison over Land based on nearly four months
of Collocations with TRMM-2B31
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F16 and N18 Rainfall Rate Compared to TRMM-2B31
Rainfall Rate Over Land 2/2
F16 and N18 rainfall rate show similar
probability distribution of rainfall rate when
compared to TRMM-2B31 Rainfall Rate over Land.
Binsize1.0 mm/hr
Binsize1.0 mm/hr
F16 Rainfall Rate (mm/hr)
N18 Rainfall Rate (mm/hr)
Comparison over Land based on nearly four months
of Collocations with TRMM-2B31
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F16 and N18 Rainfall Rate Compared to TRMM-2B31
Rainfall Rate Over Ocean 1/2
F16 rainfall rate has shown comparable
correlation, bias and standard deviation than N18
rainfall rate when compared to TRMM-2B31
Rainfall Rate over Ocean.
Corr0.5896 nPts23552 Bias-0.0101 Stdv0.45084
Corr0.4099 nPts34346 Bias-0.0041 Stdv0.54404
TRMM-2B31 Rainfall Rate (mm/hr)
F16 Rainfall Rate (mm/hr)
N18 Rainfall Rate (mm/hr)
Comparison over Ocean based on nearly four months
of Collocations with TRMM-2B31
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F16 and N18 Rainfall Rate Compared to TRMM-2B31
Rainfall Rate Over Ocean 2/2
F16 and N18 rainfall rate show similar
probability distribution of rainfall rate when
compared to TRMM-2B31 Rainfall Rate over Ocean.
Comparison over Ocean based on nearly four months
of Collocations with TRMM-2B31
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II. MIRS Rainfall Rate Validation with CPC
Precipitation.
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CPC Gauge-Based Analysis Precipitation
NOAA Climate Prediction Center (CPC) Gauge-Based
Analysis of Global Daily Precipitation represents
a unified precipitation product with consistent
quantity and improved quality that combines all
information sources (state networks, automatic
stations, etc.) available at CPC.
Number of CPC Gauge Stations
CPC Daily Precipitation
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Comparison Between Daily CPC Precipitation and
Daily Precipitation Estimate from N18 and F16
Over North America 1/2
Precipitation Estimate N18
CPC Precipitation
Precipitation Estimate F16
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Comparison Between Daily CPC Precipitation and
Daily Precipitation Estimate from N18 and F16
Over North America 2/2
MIRS F16 vs CPC Precipitation
MIRS N18 vs CPC Precipitation
Corr0.425106 nPts3893 Bias0.56842 Stdv5.86196
Corr0.522465 nPts3893 Bias-2.53102 Stdv14.6943
F16 Precipitation Estimate shows correlation,
bias and standard deviation comparable to N18
Precipitation Estimate relative to CPC
Precipitation
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Comparison Between MIRS and CPC Daily
Precipitation Over North America
Correlation between F16 Precipitation Estimate
(PE) and CPC Precipitation is comparable to the
correlation computed between CPC Precipitation
and both N18 PE and MetopA PE.
Composite Precipitation Estimate (N18, MetopA and
F16)
Precipitation Estimate From Single Sensor
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Daily Precipitation Estimate From Single and
Multiple Sensors (F16, MetopA and N18)
MIRS Precipitation Estimate (Composite N18,
MetopA and F16)
Precipitation Estimate N18
Precipitation Estimate F16
Precipitation Estimate MetopA
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Comparison Between MIRS and CPC Daily
Precipitation Over North America
Comparisons between MIRS and CPC precipitation
are being performed on a daily basis over North
America. These comparisons have been performed
daily for more than a month.
CPC Precipitation
MIRS Precipitation Estimate (Composite N18,
MetopA and F16)
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Comparison Between MIRS and CPC Daily
Precipitation Over North America
The F16 rainfall rate improves rainfall detection
in the MIRS Composite Precipitation Estimate,
without significantly affecting the number of
false alarms.
Contribution of F16 rainfall rate to MIRS
Precipitation Estimate
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Comparison Between MIRS and CPC Daily
Precipitation Over North America
F16 rainfall rate improves the correlation
between MIRS Composite Precipitation Estimate and
CPC Precipitation.
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Conclusions

• From comparisons with TRMM-2B31, F16 Rainfall
  Rate performance over land and ocean is
  comparable to the N18 Rainfall Rate.
• As expected, the F16 Rainfall Rate distribution
  reproduces the properties of the MSPPS
  distribution.
• Addition of F16 Rainfall improves the probability
  of detection and correlation coefficient of the
  MIRS Composite Precipitation Estimate with
  respect to CPC precipitation.
• Validation results of F16 Rainfall Rate, which
  includes comparison with radar-based (TRMM-2B31),
  passive microwave-based (N18) and rain gauge (CPC
  precipitation) observations, have shown that F16
  Rainfall Rate is a MIRS product ready for
  operations over land and ocean surface types.
• Finally, as shown in previous presentations,
  improvements to MIRS Rainfall Rate algorithm are
  in progress.

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Contribution of F16 Rainfall to the MIRS
Composite Precipitation Estimate
MIRS Precipitation Estimate N18, MetopA and F16
MIRS Precipitation Estimate N18 and MetopA
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Comparison Between MIRS and CPC Precipitation
Over North America