Eric A' Smith NASAGoddard Space Flight Center, Greenbelt, MD 20771

1
Microphysics, Meteorology, Microwaves, Modeling
of Mediterranean Storms The M5 Problem
Eric A. Smith NASA/Goddard Space Flight Center,
Greenbelt, MD 20771 301-286-5770
301-286-1626 easmith_at_pop900.gsfc.nasa.gov Steve
Fiorino (Fla. State University Tallahassee),
Alberto Mugnai (Inst. Atmospheric Physics/CNR,
Rome), Giulia Panegrossi (Univ. of Wisconsin,
Madison), Gregory Tripoli (Univ. of Wisconsin,
Madison)

• 3rd EGS Plinius Conference on Mediterranean
  Storms
• October 1-3, 2001 Baja Sardinia, Italy
• Session 2 Remote Sensing
• New Sensors New Satellites

2
Overall Scientific Goal of Study
Understand both macro-scale (meteorological
processes) micro-scale (microphysical
processes) governing cm-mm passive microwave
(PMW) brightness temperatures (TBs) Ku-Ka band
radar reflectivities (Zs) of extra-tropical
flood-producing Mediterranean storms in
preparation for GPM mission through combination
of remote sensing nonhydrostatic cloud modeling
to ensure improvement adaptation of next
generation GPM rain-retrieval algorithms to
extra-tropical precipitation systems.
3
Focus of this Presentation
Analyze microphysical variability of three alpine
flood-producing Mediterranean storms in northern
Italy (1) Genova (Sep 25-28, 1992), Friuli (Oct
5-7, 1998), Piemonte (Oct 13-16, 2000) relative
to prototypical tropical system observed by TRMM
satellite (viz Hurricane Bonnie in western
Atlantic Aug 21-28, 1998). This helps define
relationships between salient microphysics /
microphysical transitions during storm
meteorological life cycles signatures to be
observed in microwave instruments, and helps
identify physical determinants in cloud-radiation
relationships which will underlie next generation
of rain profile algorithms.
4
Total LWP and IWP Histograms Hurricane Bonnie
(98), Genova MCS (92), Friuli MCS (98),
Piemonte ETS (00)

• Bonnie LWP
• Genova LWP
• Friuli LWP
• Piemonte LWP

Normalized Frequency

• Bonnie IWP
• Genova IWP
• Friuli IWP
• Piemonte IWP

Normalized Frequency
Liquid/Ice Water Path Bin (kg m-2)
5
Normalized LWP Histogram Time Series Hurricane
Bonnie, Genova MCS, Friuli MCS, Piemonte ETS
Hours 0-1
Hours 2-3
Hours 4-5
Frequency
Hours 6-7
Hours 8-9
Hours 10-11
Frequency
Hours 16-17
Hours 14-15
Hours 12-13
Bonnie Genova Friuli Piemonte
Frequency
LWP Bin (kg m-2)
LWP Bin (kg m-2)
LWP Bin (kg m-2)
6
Normalized IWP Histogram Time Series Hurricane
Bonnie, Genova MCS, Friuli MCS, Piemonte ETS
Hours 0-1
Hours 2-3
Hours 4-5
Frequency
Hours 6-7
Hours 8-9
Hours 10-11
Frequency
Hours 16-17
Hours 14-15
Hours 12-13
Genova Bonnie Friuli Piemonte
Frequency
IWP Bin (kg m-2)
IWP Bin (kg m-2)
IWP Bin (kg m-2)
7
Average Liquid Water Path, Ice Water Path,
Rainrate Hurricane Bonnie (98), Genova MCS
(92), Friuli MCS (98), Piemonte ETS (00)
1. Early Piemonte Convection (10-14-00/00
UTC) 2. Genova 2nd Peak _at_ Genova
(9-28-92/00 UTC) 3. Genova 1st Peak in France
(9-27-92/04 UTC) 4. Bonnie Peak
(8-26-98/12 UTC) 5. Friuli Peak (10-6-98/20
UTC) 6. Piemonte Broad Stratiform Peak
(10-14-00/19 to 10-15-00/10 UTC) 7. Genova
Weakening Prior to 2nd Peak (9-27-92/13
UTC) 8. Bonnie _at_ Landfall (8-27-98/00 UTC) 9.
Friuli Weakening _at_ Peak Elevation
(10-7-98/08 UTC) 10. Friuli Break-up with
Isolated Convection (10-7-98/12 UTC)
Bonnie LWP Bonnie IWP Bonnie RR Genova LWP Genova
IWP Genova RR Friuli LWP Friuli IWP Friuli
RR Piemonte LWP Piemonte IWP Piemonte RR
Genova time series segmented to centrally
display beginning ending peaks
2
3
4
7
LWP/IWP (kg m-2)
Rainrate (mm h-1)
8
1
5
10
9
6
Elapsed Time from Peak (hours)
8
NMS Bonnie Simulation Aug 26, 1998 (1200UTC)
Peak Intensity
(1) Water Vapor Pristine Crystals
9
NMS Bonnie Simulation Aug 26, 1998 (1200UTC)
Peak Intensity
(2) 1 Snow Flakes
10
NMS Bonnie Simulation Aug 26, 1998 (1200UTC)
Peak Intensity
(3) 2 Aggreagate Particles
11
NMS Bonnie Simulation Aug 26, 1998 (1200UTC)
Peak Intensity
(4) 3 Cloud Droplets
12
NMS Bonnie Simulation Aug 26, 1998 (1200UTC)
Peak Intensity
(5) 4 Rain Drops
13
NMS Bonnie Simulation Aug 26, 1998 (1200UTC)
Peak Intensity
(6) 5 Graupel Particles (ALL)
14
NMS Bonnie Simulation Aug 27, 1998 (0000UTC)
Landfall
ALL 6 Hydrometeors
15
NMS Friuli Simulation Oct 6, 1998 (2000UTC)
Peak Intensity
(1) Water Vapor Pristine Crystals
16
NMS Friuli Simulation Oct 6, 1998 (2000UTC)
Peak Intensity
(2) 1 Snow Flakes
17
NMS Friuli Simulation Oct 6, 1998 (2000UTC)
Peak Intensity
(3) 2 Aggreagate Particles
18
NMS Friuli Simulation Oct 6, 1998 (2000UTC)
Peak Intensity
(4) 3 Cloud Droplets
19
NMS Friuli Simulation Oct 6, 1998 (2000UTC)
Peak Intensity
(5) 4 Rain Drops
20
NMS Friuli Simulation Oct 6, 1998 (2000UTC)
Peak Intensity
(6) 5 Graupel Particles (ALL)
21
NMS Friuli Simulation Oct 7, 1998 (0800UTC)
Weakening at High Elevation
ALL 6 Hydrometeors
22
NMS Friuli Simulation Oct 7, 1998 (1200UTC)
Late Re-intensification
ALL 6 Hydrometeors
23
TRMM GPM Rainrate Retrieval Simulations
Under Varying Mean Adj Drop Diameter Profiles
simulations based on Monte Carlo proliferation of
Hurricane Bonnie observations
TRMM Single-Frequency Algorithm (bias due to
unretrievable DSD variability)
GPM Dual-Frequency Algorithm (near-zero bias
reduced scatter in mid-range)
R e t r i e v e d R (mm hr-1)
Actual R (mm hr-1)
Actual R (mm hr-1)
Standard Deviation of R () as Function of R in
mm hr-1)
TRMM
with R approximately log-normal then sR
proportional to R
exact variability depends on DSD variability in
altitude
GPM
Percent
12.5 mm hr-1
1.5 mm hr-1
24
Rainrates at Peak Intensity Stage
Friuli MCS Simulation 100620 UTC 1998
Hurricane Bonnie Simulation 082612 UTC 1998
Periphery
Eyewall (central)
Central Convection
Outer Rainband (periphery)
Piemonte ETS Simulation 101504 UTC 2000
Genova MCS Simulation 092800 UTC 1992
Periphery
Periphery
Central Convection
Central Convection
25
Rainrates at Weakening Stage
Friuli MCS Simulation 100708 UTC 1998
Hurricane Bonnie Simulation 082700 UTC 1998
Eyewall (central)
Periphery
Central Precipitation
Outer Rainband (periphery)
Piemonte ETS Simulation 101516 UTC 2000
Genova MCS Simulation 092712 UTC 1992
Periphery
Central Convection
Periphery
Central Precipitation