Transcript 121205SanFrancisco_AGU_FellowsV16_Houze.pptx

Satellite Radar Studies of
Extreme Convective Storms
Rockies
Himalayas
?
Andes
Robert A. Houze, Jr.
University of Washington
New Fellows Presentation, AGU, San Francisco, 5 December 2012
Radars in Space
CloudSat
2006-
TRMM
1997-
Typical Tropical Convective Cloud
Population
CloudSat
TRMM
3 mm wavelength
2 cm wavelength
Locations of the deepest and most intense
convective cores seen by TRMM over ~14 years in
South Asia and South America warm seasons
JJAS
Romatschke et al. 2010
DJF
Romatschke and Houze 2010
Near the large mountain ranges
Relationship to Mountain Ranges and Moisture
Sources
Rockies
Himalayas
?
Andes
How similar are the storms in
these three regimes?
The North American Case
Carlson et al. 1983
Mexican
Plateau
Texas
Gulf of
Mexico
Something similar happens to
extreme convective cores in the
western region of South Asia
Sawyer 1947
A case observed by TRMM
TRMM PR Observations
WRF Simulation
Medina et al. 2010
Backward trajectories (HYSPLIT/NCEP)
2.5 km
1.0 km
Consistent
Consistentwith
withSawyerwith
Consistent
Sawyer 1947
Sawyer
1947 1947
Medina et al. 2010
WRF Model Simulation
Mixing ratio
CAPE
Surface wind
Medina et al. 2010
WRF Simulation
Cloud just after
convection formed
in the model
Triggering is over
foothills—consistent
with satellite data
Medina et al. 2010
A similar
regime occurs near the Andes
Convective Regimes in South America
Identified by TRMM
Romatschke and Houze 2010
Example of
triggering over
the Sierra
Cordóba
range
Rasmussen & Houze
2011
What the storm
looked like on
the TRMM
radar
Rasmussen and Houze 2011
Vertical air motions
COMPOSITE
of average
conditions for
storms with
intense
convection
seen by the
TRMM radar
Rasmussen and Houze 2011
up down
Low-level winds
moist
unstable
Recap
LARGE MOUNTAIN RANGES NEAR WARM MOIST ZONES
SIMILARITIES
Rockies
Himalayas ?
• Channeling of moisture
• Downwind capping
Andes
• Explosive triggering
DIFFERENCES
• Capping may be downslope from a plateau or
response to flow over a ridge
• Triggering may be meteorological or orographic
Similar studies
• Pakistan flood cases
• Convection in the MaddenJulian Oscillation
• Storm systems over land and
ocean
• Other…
The future
GPM
Rockies
TRMM
CloudSat  EarthCare
Himalayas
?
Next generation:
Radars need
to be in the
same orbit!
Andes
This research was supported by
NASA grants NNX10AH70G, NNX10AM28G,
and NSF grant AGS1144105
End
Rockies
Himalayas
?
Andes
This research was supported by
NASA grants NNX10AH70G, NNX10AM28G,
and NSF grant AGS1144105
End
Rockies
Himalayas
?
Andes
This research was supported by
NASA grants NNX10AH70G, NNX10AM28G,
and NSF grant AGS1144105
Global Pattern of Deep Convection
seen by TRMM
Maximum height of TRMM’s most intense radar echoes
Zipser et al. 2006