Global Hawk #872 09/19/12 - 09/20/12

Download PDF
Flight Number: 
872-0099
Payload Configuration: 
HS3 - TN872 2012 config
Nav Data Collected: 
No
Total Flight Time: 
24.8 hours
Flight Segments: 
From:WFFTo:WFF
Start:09/19/12 18:41 Z Finish:09/20/12 19:28 Z
Flight Time:24.8 hours
Log Number:12H002PI:Marilyn Vasques
Funding Source:Hal Maring - NASA - SMD - ESD Radiation Science Program
Purpose of Flight:Science
Comments:Science target was Tropical Storm Nadine, making this flight the third visit to Nadine. 76 sondes were deployed, which, according to NCAR is a new record for a single aircraft flight.
Flight Hour Summary: 
12H00213H008
Flight Hours Approved in SOFRS327
Flight Hours Previously Approved 178.1
Total Used148.946
Total Remaining 132.1
13H008 Flight Reports
Date Flt # Purpose of Flight Duration Running Total Hours Remaining Miles Flown
10/06/12872-0102Science7.37.3170.8
10/12/12872-0103Ferry9.717161.1
11/01/12871-0082Check4.821.8156.3
11/05/12 - 11/06/12871-0083Science24.246132.1
12H002 Flight Reports
Date Flt # Purpose of Flight Duration Running Total Hours Remaining Miles Flown
08/28/12872-0094Check5.55.5321.5
08/30/12872-0095Maintenance0.76.2320.8
09/06/12 - 09/07/12872-0096Science19.325.5301.5
09/11/12 - 09/12/12872-0097Science25.751.2275.8
09/14/12 - 09/15/12872-0098Science22.473.6253.4
09/19/12 - 09/20/12872-0099Science24.898.4228.6
09/22/12 - 09/23/12872-0100Science25.1123.5203.5
09/26/12 - 09/27/12872-0101Science25.4148.9178.1

Flight Reports began being entered into this system as of 2012 flights. If there were flights flown under an earlier log number the flight reports are not available online.

Related Science Report: 

HS3 - Global Hawk #872 09/19/12 - 09/20/12 Science Report

Mission: 
HS3
Mission Summary: 

Hurricane and Severe Storm Sentinel (HS3) Mission

19-20 September 2012 Flight Report

Flight Scientists:

Shift 1 (1600-0100 UTC): Robert Houze, Deanna Hence

Shift 2 (0100-0900 UT): Paul A. Newman, Michael Montgomery, Steve Guimond

Shift 3 (0900-1600 UT): Scott Braun, Ed Zipser

Shift 4 (1600-2000 UTC): Robert Houze, Deanna Hence

Mission: Flight 3 over Nadine was executed over the eastern Atlantic region near the Azores. The original flight plan consisted of an east-west oriented lawnmower pattern with its eastern portion at the longitude of the Azores, with a slightly altered leg to fly between islands. The storm showed no significant signs of development or decay during the flight. The cloud tops were generally well below flight level with no lightning for the entire mission. No flight diversions were required, although legs 2 and 3 were displaced northward to better overfly the storm center. A total of 76 sondes were launched. Many had data dropouts, especially in the lower levels. Some sondes were missed due to ATC conflicts. Near the storm center, between planned drop points 31 and 36, a salvo of dropsondes were launched at 2.5 min intervals. The storm was lingering over a region of strong SST gradient. Little baroclinic shear was evident in the vicinity of the vortex. A large tongue of dry air was seen to be wrapping into the southeastern quadrant of the storm circulation. Dropsondes indicate extremely dry air in the mid- and upper-levels. The dropsondes indicate that the vortex is not well defined above 300 mb.            

Mission Scientist narrative follows:

1842 UTC Take off

Flight plan

We now have a Mission Scientists BOOK at the Mission Science station. During this flight we’ve added some notes and additional material. During this shift we have added some pages and comments to the book.

  1. First, we have added the membership lists of two list serves, which may be needed during a mission
    1. The “hurricane-flight-plan” list includes not only NASA pilots, mission directors, and payload managers but also NOAA and Air Force pilots and CARCAH. This list should NOT be used unless NOAA, Air Force, and CARCAH personnel need to be notified. Otherwise, use the following list.
    2. The “hs3-mission-science” list, which includes the Global Hawk pilots, Mission Directors, Payload Managers and Mission Scientists, i.e. all the people who may be on duty during a Global Hawk flight needs to make a flight diversion and information about new coordinates needs to be passed.
    3. We have also added an updated version of Ed Zipser’s cloud-top temperature to cloud-top height conversion graph to the BOOK.
    4. We have flagged as “IMPORTANT” the procedure for making a flight track diversion and specified that the notification should be done via the “hs3-mission-science” list mentioned above.
    5. We used sticky notes to mark some of the most important pages. Some more permanent page markers would advisable to attach to these key pages.

Drop 1, 2153 UTC, no data showing below 600 hPa

Flight progress at 2155UTC

Flight progress at 0100

Drop 2, 0106 UTC

Drop 3, 0116 UTC

Drop 4, 0126Z

Drop 5, 0134Z

Drop 6, 0146Z

Drop 7, 0155Z

 

CIMSS brightness temperature  (2012-09-20, 0115Z)  Aircraft position valid for 0149Z. Note the lack of high cloud. Lightning activity was zero over the entire area of the storm at this time.

Drop 8, 0204

Drop 9, 0214

Drop 10, skipped (air traffic)

Drop 11, skipped (air traffic)

Drop 12, 0243

Drop 13, 0255

Drop 14, 0304

Drop 15, 0312

Drop 16, skipped (air traffic)

Drop 17, skipped (air traffic)

Drop 18, 0345

Drop 19, 0357

Drop 20, 0406

Water vapor imagery of TS Nadine with flight track on top.  Note dry slot wrapping into storm that was sampled by dropsondes.  We made some slight modifications of the flight track in order to sample the center of Nadine with sondes.  Currently on a 20 nmi displacement to the North of original track and will do a 40 nmi North displacement on next W-E leg.  We will drop 6 missed sondes centered on the center of Nadine on the next W-E leg.

Drop 21, 0416

Drop 22, 0426

Drop 23, 0436

Drop 24, 0446

Drop 25, 0454

Drop 26, 0505

Drop 27, 0518

Drop 28, 0529

Water vapor imagery of TS Nadine with flight track on top.  Some sondes were missed due to air traffic interference and other sondes did not get full data coverage possibly due to RFI.  Currently on a 40 nmi displacement to the North of original track.  We will drop 6 previously missed sondes centered on the center of Nadine (36.7N, 31.2W) on this leg.  The red arrow in the above figure indicates an example sonde shown below…

Dropsonde highlighted in the previous figure (red arrow).  Good data all the way down to the surface.  Max winds of 50 kts at ~ 800 hPa, decreasing with height above.  Data point in the boundary layer is 35 kts with an inflow component .  This is to be expected in a frictional boundary layer.  Near moist adiabatic ascent is present from ~ 950 hPa up to ~ 250 hPa.  At ~ 250 hPa a very sharp gradient in moisture is evident with an associated temperature inversion.

Drop 29, 0537

Drop 30, 0547

Drop 31, 0556

Note: Drop 32 and Drop 33 have been absorbed into the rapid drop cycle and are labeled r1 - r7. 

START RAPID DROP

Drop r1, 0603

Drop r2, 0606

Drop r3, 0609

Drop r4, 0611

Drop r5, 0614

Drop r6, 0616

Drop r7, 0619

END RAPID DROP

Drop 32, 0624

CIMSS brightness temperature at 0600.  This was approximately the time that we passed over the forecast position of the storm center.

Drop 35. 0633Z

Scanning HIS 895-905 channel showing very cold Tb near the core of the storm. The CPL data had high cloud of ~12km altitude at this point.

Drop 36, 0642

0642 – air traffic has led to a suspension of sondes for the moment.

Drop 37, 0650

Drop 38, 0700

Note: slight deviation from track due to Azores islands.

Drop 39, skipped (due to air traffic)

Drop 40, skipped (due to air traffic)

Drop 41, skipped (due to air traffic)

Drop 42, 0732

Drop 43, 0739

 

Example of some of the problems we have been seeing in the sonde data.  There is a data gap (temperature, moisture and winds) in low - mid levels, which is fairly typical for the problem sondes.  Most sondes were good quality, but we estimate that ~ 25 % have had failures.

Drop 44, 0749

Good morning, Nadine.  Snapshot from the HDVIS camera on the AV-6 showing cirrus clouds in the periphery of TS Nadine at 0751 UTC 9/20/2012.

Drop 45, 0758

Drop 46, 0806

Planning three extra drops during this leg after planned drop locations D47-D49. (Image above was taken after completing the drops).

Drop 47, 0816

Drop 47.5, 0821

Drop 48, 0827

Drop 48.5, 0831

Drop 49, 0837

Drop 49.5, 0842

Drop 50, 0848

 

Drop 31 shown above has some of the strongest winds close to the surface. The drop appeared to be in a rainband on the western side of the storm, but about 100-150 km from the center.

Drop R6 is shown above and appears to have the warmest moist adiabat of all of the soundings.

Drop 51, 0852                

GH data influenced the NHC discussion of Nadine. Text is below.

000
WTNT44 KNHC 200838
TCDAT4

TROPICAL STORM NADINE DISCUSSION NUMBER 36
NWS NATIONAL HURRICANE CENTER MIAMI FL AL142012
500 AM AST THU SEP 20 2012

IT IS HARD TO SAY MUCH MORE ABOUT NADINE. THE INITIAL INTENSITY CONTINUES AT 45 KNOTS...ALTHOUGH...PRELIMINARY DROPSONDE DATA FROM THE NASA GLOBAL HAWK AIRCRAFT SUGGEST THAT WINDS COULD BE A LITTLE STRONGER ON THE WESTERN SEMICIRCLE. THE ONLY SIGNIFICANT CHANGE IS THE INCREASE IN CONVECTION NEAR CENTER DURING THE PAST FEW HOURS. THIS SUGGESTS THAT NADINE IS NOT BECOMING POST-TROPICAL AT THIS TIME...AND IN FACT...IT LOOKS MORE TROPICAL NOW THAN 24 HOURS AGO. HAVING SAID THAT...NADINE IS STILL FORECAST TO TRANSFORM INTO A POST-TROPICAL CYCLONE GIVING THAT IS MOVING OVER COOL WATERS. THE CONFIDENCE IN THIS FORECAST IS VERY LOW.

AS ANTICIPATED BY GLOBAL MODELS...THE FLOW ON THE SOUTH SIDE OF A STRONG MID-LEVEL TROUGH IS FORCING NADINE TO MOVE TOWARD THE EAST-SOUTHEAST OR 120 DEGREES AT 8 KNOTS. AS THE TROUGH SWINGS EASTWARD...THE NORTHWESTERLY FLOW FOLLOWING THE TROUGH WILL STEER NADINE TOWARD THE SOUTHEAST FOR THE NEXT 2 TO 3 DAYS. BY THEN...THE TROUGH WILL BE REPLACED BY A STRONG RIDGE...AND NADINE WILL LIKELY BECOME TRAPPED SOUTH OF A BLOCKING HIGH PRESSURE. IN THE LONG RANGE...BOTH THE GFS AND THE ECMWF MODELS KEEP CHANGING THEIR TUNES...AND WHEN THE GFS SHOWS A WESTWARD TURN...THE ECMWF SHOWS AN EASTWARD MOTION...AND VICEVERSA. SINCE THIS IS THE CASE AGAIN TONIGHT...THE NHC FORECAST PREFERS TO KEEP NADINE NEARLY STATIONARY BEYOND 72 HOURS.

FORECAST POSITIONS AND MAX WINDS

INIT  20/0900Z 36.8N  30.6W   45 KT  50 MPH
 12H  20/1800Z 36.2N  29.4W   45 KT  50 MPH
 24H  21/0600Z 35.0N  27.5W   45 KT  50 MPH
 36H  21/1800Z 33.5N  26.5W   45 KT  50 MPH...POST-TROPICAL
 48H  22/0600Z 32.5N  26.0W   45 KT  50 MPH...POST-TROPICAL
 72H  23/0600Z 32.0N  26.0W   45 KT  50 MPH...POST-TROPICAL
 96H  24/0600Z 32.0N  25.9W   45 KT  50 MPH...POST-TROPICAL
120H  25/0600Z 32.0N  26.0W   45 KT  50 MPH...POST-TROPICAL

$$
FORECASTER AVILA

Drop 52, 0901

Drop 53, 0910

Drop 54, 0919

Drop 55, 0930

Drop 56, 0938

Drop 57, 0947

Drop 58, 0956

Drop 59, 1005

Drop 60, 1014

Drop 61, 1023

Drop 62, 1032

Drop 63, 1041

Drop 64, 1050

Drop 65, 1100

Drop 66, 1107

1109—ATC asked us to stop drops for 15 min due to nearby air traffic.

Drop 68, 1128

Drop 69, 1134

Drop 70, 1143

Drop 71, 1152

Drop 72, 1200

Drop 73, 1210

Drop 74, 1218

Drop 75, 1226

Drop 76, 1235

1238—Traffic below us for a while, no drops for ~30 min, which effectively ends our drops for the flight since we had only a few left.

Flight progress at 1730 UTC

Landing at about 1905 UTC.

Images: