Preliminary Results from ICET Paul Lawson Summary of

Preliminary Results from ICE-T Paul Lawson

Summary of Learjet ICE-T Missions Ø Lear flew a total of 12 ICE-T Missions. Ø 10 of the 12 Learjet Missions were in Conjunction with the C-130 and one (30 July) was a Coordinated Formation Flight. Ø Approximately 150 Penetrations of Cloud Turrets with Temperatures between +22 C and -24 C. Ø Most Cloud Penetrations were between 0 C and -20 C, with the Major Focus on the Region between -5 C and -20 C.

L e a r J e t I n s t r u m e n t a t s

Growing ICE-T Tropical Cumulus Clouds are Typically Mixed-Phase from about – 10 C to – 20 C. 2 D Images do Not have Sufficient Fidelity to Separate Water Drops from Ice Particles in ICE-T Clouds

2 D-S Images in Decaying Turret Appear to be All Ice (Rice Probe Indicates no SLWC) CPI Images at Same Time Show Low Concentration of Supercooled Drops

Another Example of 2 D-S Images in the Middle of the Decaying Turret CPI Images at the Same Time Show Several Supercooled Drops (No Activity on Rice)

3 V-CPI (CPI Portion) Images are used in Conjunction with 2 D-S Image Data to Provide Quantitative Water Drop and Ice Particle Size Distributions and Derived Quantities

Examples of CPI Images in Mixed-Phase at -17 C

Examples of CPI Images in Mixed-Phase at -17 C

Examples of CPI Images in Mixed-Phase at -17 C

Examples of CPI Images in Mixed-Phase at -17 C

CPI Images in Mixed-Phase Automatically Separated into: Water and Ice

Particle Size Distributions from Various Probes

Using CPI Automatic Image Recognition to Generate FFSSP 2 D-S HVPS Water and Ice Size Distributions in Mixed-Phase

Example Comparison of Lear and C-130 in situ Measurements with Remote Observations Ø 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. Ø 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 3 CV-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 3 V-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

2 D-S Images of Supercooled Drops in Turret Updraft

2 D-S Images of Ice Particles in the Old Cloud Region

C-130 UW Cloud Radar Data for 1726 Cloud Penetration

Lear and C-130 3 V-CPI Particle Size Distributions

First Ice in Tropical Cumulus Clouds Paul Lawson

A Simple Methodology to Analyze First Ice I. Automatically categorize water drops and ice crystals for each cloud penetration with working CPI data. II. Classify clouds having number concentrations of < 2% ice crystals with a mean size < 50 µm as being those containing first ice. III. Evaluate the amount and type of first ice as a function of cloud temperature, updraft speed, aerosols, cloud appearance, etc. Caveats Ø Care must be taken not to include old cloud fragments outside of growing turrets Ø 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

First Ice at -12 C Observed at 190623

More Examples of First Ice at -12 C

Particle Size Distributions from Various Probes

Composite Water Drop Size Distribution from FFSSP, 2 D-S, & HVPS and CPI Images of First Ice (1. 3% of total particles) at – 12 C