AIRBORNE FIELD MILL PROJECT
KENNEDY SPACE CENTER

SYNTHESIS FOR JUNE 12, 2000 - ABFM

Flight Summary (Non-Anvil Day)

Case 1 (Times: 1430 - 1730)
Type of case convective
Complexity complex
Convection convective band
Electric field
  kV/m
Min Em_m = 0.013
Max Em_m = 37.771
Mean Em_m = 2.198
Microphysics
  #/Liter
Max CON_FSSP = 46115.359
Mean CON_FSSP = 2140.716
Max Tot_con_1DC = 1162.351
Mean Tot_con_1DC = 45.366
Max Tot_con_2DC = 1967.496
Mean Tot_con_2DC = 56.620
Max 2DC_100_400 = 946.153
Mean 2DC_100_400 = 26.423
Max 2DC_400_1000 = 91.034
Mean 2DC_400_1000 = 4.719
Max 2DC_GT_1000 = 2.780
Mean 2DC_GT_1000 = 0.215
Location (x,y) ~ (-50,80)
Storm Motion 1.1 m/s to the west, 3.7 m/s to the north gives: 3.7m/s NW

Brief Description

Possibly a good case to study decay of electric fields and/or debris.

Case 2 (Times: 1730 - 1745)
Type of case edge of convection
Complexity complex
Convection convective band
Electric field
  kV/m
Min Em_m = 0.118
Max Em_m = 1.757
Mean Em_m = 0.289
Microphysics
  #/Liter
Max CON_FSSP = 14783.568
Mean CON_FSSP = 675.146
Max Tot_con_1DC = 66.608
Mean Tot_con_1DC = 1.561
Max Tot_con_2DC = 56.282
Mean Tot_con_2DC = 1.860
Max 2DC_100_400 = 22.192
Mean 2DC_100_400 = 0.720
Max 2DC_400_1000 = 9.441
Mean 2DC_400_1000 = 0.302
Max 2DC_GT_1000 = 1.226
Mean 2DC_GT_1000 = 0.027
Location (x,y) ~ (-50,50)
Storm Motion 1.1 m/s to the west, 3.7 m/s to the north gives: 3.7m/s NW

Brief Description

Aircraft was flying to the west of an active cell.



Case 1: When the cappi loop is run this starts out as a single cell, but it "breaks up", just before the aircraft gets there, into several separate pieces. Lightning occurs during the flight. Although this would not be good for electrical initiation (aircraft gets there too late), nor for anvil studies, it might be good for electrical decay. Cloud tops are above 10 km with active lightning while the aircraft flies through the primary cell.

Case 2: Aircraft was flying to the west of an active cell.







SYNTHESIS FOR JUNE 12, 2000 - ABFM

Investigator: None
[Not presented at a teleconference.]


The following summary is from the notes that Jim Dye and Eric Defer put together. Probably early in 2001 (before the May/June 2001 Field Campaign).

prepared by Jim Dye with help from Eric Defer


 

 

E fields reported in the summaries below are based on the old matrix for determination of the three components of the field. The new matrix provided in April 2001 reduces the negative values of Ez as much as 40 to 60%. So the values reported herein may be too large. Positions are reported herein as (X,Y) coordinates relative to the WSR74-C radar.

Th total concentrations of particles measured by the 2D-C probe are denoted as N30 (ie. concentration of particles >30 microns which is heavily weighted towards smaller particles). N1 refers to the concentration of particles >1mm size, ie. the larger particles. Radar plots were available for only a few of the last summaries we prepared (June 4, 6, and 11). For other days some of the realtime radar plots were utilized but need to be verified.

 

June 12

The Citation flight was from 1425—1755 with passes primarily at 7.9 km (-24C). It first investigated a small storm south of Daytona Beach at (-50,80) with 6 or 7 flashes (3 or 4 CGs) from 1433 to 1456. Another bigger storm developed to the SW with first lightning at ~1535 as A/C working first storm, but too active to work and couldn’t get clearance. First pass at 1450 shows Ez to –40 KV/m. Successive passes until 1607 show Ez >15 KV/m often as large as 40 to 60 KV/m (e.g. 1548 and 1553) even though no lightning after 1456. A/C continued passes until ~1725. Ez after 1630 <few KV/m and probably <1KV/m by 1700.

N30 = 200 –1000 /L until 1610 with N1 ~ 0.5 –1 /L. After 1615 N30 usually 100 /L or less and N1 ~ 0.1 to 1/L. After 1700 N30 ~50/L or less and N1 0.05 to0.5 /L. Realtime radar plots suggest radar tops in excess of 30,000 ft with 40 dBZ to 20,000 ft near 1530, but need to verify this. Last realtime RHI at 1637 suggests 20dBZ max at this time. Appears to be a case with weak updrafts which did produce lightning early on and continued to have charge separation occurring until ~1600-1605 with updrafts dying afterwards. May be interesting to look at Doppler data from 74C for hints of updraft strength.

CHECK: How well does radar show evidence of weak, but continued convection during the period with enhanced Ez and probable threat?