350 likes | 449 Views
Preliminary Results from ICE-T. Paul Lawson. Summary of Learjet ICE-T Missions Lear flew a total of 12 ICE-T Missions. 10 of the 12 Learjet Missions were in Conjunction with the C-130 and one (30 July) was a Coordinated Formation Flight.
E N D
Preliminary Results from ICE-T Paul Lawson
Summary of Learjet ICE-T Missions • Lear flew a total of 12 ICE-T Missions. • 10 of the 12 Learjet Missions were in Conjunction with the C-130 and one (30 July) was a Coordinated Formation Flight. • Approximately 150 Penetrations of Cloud Turrets with Temperatures between +22 C and -24 C. • Most Cloud Penetrations were between 0 C and -20 C, with the Major Focus on the Region between -5 C and -20 C.
I n s t r u m e n t a t s L e a r J e t
Growing ICE-T Tropical Cumulus Clouds are Typically Mixed-Phase from about – 10 C to – 20 C. 2D Images do Not have Sufficient Fidelity to Separate Water Drops from Ice Particles in ICE-T Clouds
CPI Images at Same Time Show Low Concentration of Supercooled Drops 2D-S Images in Decaying Turret Appear to be All Ice (Rice Probe Indicates no SLWC)
CPI Images at the Same Time Show Several Supercooled Drops (No Activity on Rice) Another Example of 2D-S Images in the Middle of the Decaying Turret
3V-CPI (CPI Portion) Images are used in Conjunction with 2D-S Image Data to Provide Quantitative Water Drop and Ice Particle Size Distributions and Derived Quantities
CPI Images in Mixed-Phase Automatically Separated into: Water and Ice
Using CPI Automatic Image Recognition to Generate FFSSP 2D-S HVPS Water and Ice Size Distributions in Mixed-Phase
Example Comparison of Lear and C-130 in situ Measurements with Remote Observations • Shown are Results from a Cloud Penetration when the Learjet flew in trail about 400 m beneath the C-130. The purpose was to compare C-130 UW cloud radar with Lear in situ measurements. • The C-130 Entered 11-s Ahead of the Lear in a Rising Turret with strong updraft and mostly SLW followed by an older decaying mixed-phase region that transitions to mostly ice. The two types of cloud can be seen in the Lear cockpit video photos. The CPI part of the Lear 3CV-CPI* malfunctioned during this cloud penetration and no images are available, so the absence of cloud drops cannot be confirmed in the mixed-phase cloud. * The 3V-CPI was made available courtesy of the US Navy Center for Interdisciplinary Remotely Piloted Aircraft Studies
Lear (purple) and C-130 (yellow) Flight Tracks During Coordinated Penetrations on 30 July 2011
Lear Cockpit Time-Lapse Photos Showing Rising Turret and Older Cloud Behind that C-130 Penetrated and Lear Penetrated 11-s later and 1,500 ft Below C-130
First Ice in Tropical Cumulus Clouds Paul Lawson
A Simple Methodology to Analyze First Ice Automatically categorize water drops and ice crystals for each cloud penetration with working CPI data. Classify clouds having number concentrations of < 2% ice crystals with a mean size < 50 µm as being those containing first ice. Evaluate the amount and type of first ice as a function of cloud temperature, updraft speed, aerosols, cloud appearance, etc. Caveats • Care must be taken not to include old cloud fragments outside of growing turrets • Care must be taken to correct any misclassified water drops and ice particles.
Example of First Ice Observed by Learjet in Cloud at -12 C on 11 July from 190615 – 190625…
All Water Drops Observed during First 7 s of Cloud Penetration (One Second – about 300 images: 190615.6 – 190616.6 shown below)
190616.6 – 190617 and 190618 – 190618.6 shown below …then skip 5 –s
Composite Water Drop Size Distribution from FFSSP, 2D-S, & HVPS and CPI Images of First Ice (1.3% of total particles) at – 12 C