Satellite Radar Studies of Extreme Convective Storms ? ? New Fellows Presentation, AGU, San Francisco, 5 December 2012 Robert A. Houze, Jr. University of Washington

Radars in Space TRMM1997- CloudSat2006-

Typical Tropical Convective Cloud Population TRMM 2 cm wavelength CloudSat 3 mm wavelength

JJASDJF Locations of the deepest and most intense convective cores seen by TRMM over ~14 years in South Asia and South America warm seasons Near the large mountain ranges Romatschke et al. 2010Romatschke and Houze 2010

Relationship to Mountain Ranges and Moisture Sources ? ?

The North American Case

Carlson et al moist Texas dry,hot Mexican Plateau 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

Consistent with Sawyer 1947 Backward trajectories (HYSPLIT/NCEP) 2.5 km 1.0 km Medina et al Consistent with Sawyer 1947

WRF Model Simulation Mixing ratio CAPE Medina et al Surface wind

Medina et al WRF Simulation Cloud just after convection formed in the model Triggering is over foothills—consistent with satellite data

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 Low-level winds COMPOSITE of average conditions for storms with intense convection seen by the TRMM radar down up moistunstable Rasmussen and Houze 2011

Recap SIMILARITIES Channeling of moisture Channeling of moisture Downwind capping Downwind capping Explosive triggering Explosive triggeringSIMILARITIES Channeling of moisture Channeling of moisture Downwind capping Downwind capping Explosive triggering Explosive triggering DIFFERENCES Capping may be downslope from a plateau or response to flow over a ridge Capping may be downslope from a plateau or response to flow over a ridge Triggering may be meteorological or orographic Triggering may be meteorological or orographicDIFFERENCES Capping may be downslope from a plateau or response to flow over a ridge Capping may be downslope from a plateau or response to flow over a ridge Triggering may be meteorological or orographic Triggering may be meteorological or orographic ? ? LARGE MOUNTAIN RANGES NEAR WARM MOIST ZONES

Pakistan flood cases Pakistan flood cases Convection in the Madden- Julian Oscillation Convection in the Madden- Julian Oscillation Storm systems over land and ocean Storm systems over land and ocean Other… Other… Similar studies

The future ? ? This research was supported by NASA grants NNX10AH70G, NNX10AM28G, and NSF grant AGS and NSF grant AGS TRMM GPM Next generation: Radars need to be in the same orbit! CloudSat  EarthCare

End ? ? This research was supported by NASA grants NNX10AH70G, NNX10AM28G, and NSF grant AGS and NSF grant AGS

End ? ? This research was supported by NASA grants NNX10AH70G, NNX10AM28G, and NSF grant AGS and NSF grant AGS

Global Pattern of Deep Convection seen by TRMM Zipser et al Maximum height of TRMM’s most intense radar echoes