Annual Interagency Weather Research Review and Coordination Meeting 30 November – 2 December 2010 Boulder, CO Julie Haggerty, Jennifer Black, Gary Cunning, Frank McDonough, Marcia Politovich, Cory Wolff NCAR Pat Minnis, Bill Smith, Chris Yost NASA LaRC
More than 100 events of jet-engine power- loss while flying in vicinity of deep convection All types/sizes of aircraft, all types/sizes of engines Hypothesis: aircraft flying in regions of high mass concentrations of ice crystals which are ingested into engines Supercooled LWC not required Location of events in tropical and midlatitude regions, oceanic and continental convection Mason, J.G., J.W. Strapp, and P. Chow, 2005: The ice particle threat to engines in flight. 44th AIAA Aerospace Sciences Meeting, Reno, Nevada, 9-12 January 2006, AIAA
HIWC Science Plan Characterize High-IWC environment during field program Improve the conceptual model of High-IWC in deep convection, and develop nowcasting techniques NCAR team Nowcasting product estimating risk due to HIWC conditions Forecasting tools for field project support Algorithm development (FAA funding) Apply satellite products to detection of HIWC regions in collaboration with NASA LaRC (NASA ROSES funding) Field program status Selection of aircraft pending Projected dates of field program Jan-Mar 2012 & 2013; Darwin, Australia
In advance of field program, use available observations from prior engine events Step through preliminary algorithm for individual case studies Determine available data sources Understand quantitative thresholds of pertinent variables Determine relative importance of possible predictors Identify gaps in information
Ambient temperature warmer than std atm (+10C?) Low radar reflectivity at flight level Precipitation below (moderate to heavy) Lightning in vicinity Thermodynamic profile (LI, CAPE, PW) PIREPS of turbulence but not icing Overshooting cloud tops Convective Conditions (thunderstorms or tropical storm; anvils) Ice phase hydrometeors (high concentration) 3-Dimensional Estimate of Probability of HIWC conditions that pose a risk to aviation Clouds in grid cell Necessary Conditions Conditions that may contribute to risk Combine using fuzzy logic
Approaching KJFK, descending from FL230 to FL210, encountered convection related to TS Hannah Approaching KORD, FL250, encountered convection associated with remnants of Hurricane Ike
RUC Model Fields Lightning Products Radiosonde Profiles Radar Reflectivity Satellite-derived cloud products
Uses two satellites viewing the same cloud from different angles Estimates IWC near top of deep convective clouds and anvils Yost et al.,JGR,2010
For each case, step through conceptual algorithm to verify expected conditions All conditions for which data were available present in these cases ▪ Clouds, ice phase, convection ▪ Low radar reflectivity at flight level, precipitation below, turbulence reported, etc. Procedure developed for analyzing case studies in other synoptic scenarios, relevant data sources identified
Field program schedule remains unconfirmed Current lack of scientific knowledge about processes driving these conditions Insufficient cases for statistical significance Many cases over oceans where fewer data sources (e.g., radar) are available Need to examine null cases as well
Case studies – seeking more events from engine events database; also hope to use PREDICT cases which include many incidents of TAT anomalies during HIWC conditions Algorithm development (scientific and engineering) Web-based diagnostic product for uplink to research aircraft
Field program to investigate hurricane initiation, based in St. Croix, Aug-Sep 2010 NSF/NCAR Gulfstream V instrumented with multiple microphysical probes (2DC, CDP, CVI, SID-2, 3V-CPI, etc.). Also carried dropsondes, GPS water vapor profiler, microwave temperature profiler, ozone analyzer 26 research flights at ~41 kft Numerous TAT anomalies associated with high IWC encounters
Preliminary Data Not for distribution
Preliminary Data Not for distribution