KA-20250929a

KA-20250929a#

ec_under mpc melt_layer precip multi marine_sc

Crew#

Job

Name

PI

Tim Carlsen

Instrument operator

Sorin Ghemulet

Instrument operator

Alex Vlad

EarthCARE target scenarios

Melting layer: Porpoising through melting layer over ocean.
Rain: Precipitating clouds over ocean.
Marine Sc: Vertical profiles including drizzle.
Complex multi-layer scenes: Multiple low cloud decks.

Flight summary

During the research flight on 29th September 2025, we targeted mixed-phase clouds, and specifically the melting layer between 1.2 and 3.5 km altitude underneath EarthCARE (orbit #7603C). We performed porpoising through the melting layer, covering temperatures between -6°C and +5°C and sampling liquid droplets, ice crystals, drizzle, rain and snow.

Track#

../_images/KA-20250929a_7603C.png

Flight track for KA-20250929a.#

Flight path (dashed line) superimposed on the MSI-RGR-1C product on 29th September 2025. The ATLID ground track is shown in yellow, while the EC leg (for correlative observations) is shown as a continuous line.

Conditions#

During the EC leg, we experienced low mixed-phase clouds (with some overlying high clouds). Mostly continuous cloud decks, but sometimes a bit broken up in the vertical. We sampled between 1.2 and 3.5 km altitude, covering temperatures between -6°C and +5°C. This way, we measured rain and snow above and below the melting layer in addition to sampling cloud droplets and ice crystals.

Flight video#

Video cutting and editing in progress…

Events#

Time (UTC)

Comment

12:53

Takeoff Kiruna

14:04

Start ec_leg

14:20

EarthCARE overpass (orbit #7603C)

14:37

End ec_leg

15:53

Landing Kiruna

Execution#

  • Takeoff KRN: 12:53 UTC (14:53 LT)

  • Hawkeye running

  • 13:20 UTC: delayed due to strong headwinds, expected arrival @WP1 at 14:00 UTC, request for arrival @FL100 so try to go down already

  • 13:30 UTC: will start descent to FL100 after we passed the mountains

  • 13:44 UTC: start descending towards WP, 800ft/min

  • 13:59 UTC: vicinity of WP1, FL150

  • 14:04 UTC, WP1, start ec_leg

  • 14:07 UTC: WPA

  • 14:10 UTC: WPB

  • 14:13 UTC: start ascent after porpoising down

  • 14:15 UTC: WPC

  • ground speed 237 kt, Temperatures from cockpit were ~2°C higher than SAT

  • 14:19 UTC: going a bit higher to cover temperatures down to -5°C

  • 14:19 UTC: start descent again, 1000 ft/min, EC overpass

  • 14:24 UTC: WPE

  • 14:27 UTC: alt capture, start ascent again

  • 14:30 UTC: WP2, continue same heading to extend ec_leg

  • 14:32 UTC: continue climb until FL150

  • 14:37 UTC: finish ec_leg, going home

  • Landing KRN: 15:53 UTC (17:53 LT)

Impressions#

  • 13:30 UTC: -34°C, TAS230, FL270, no clouds

  • 13:50 UTC: TAS240, -21°C, FL200, in-cloud, Hawkeye works, 2DS sees crystals

  • 13:52 UTC: TAS237, -20°C, FL190, FCDP sees droplets + small ice in 2DS, many thin layers

  • 13:54 UTC: TAS228, -17°C, FL170

  • 13:56 UTC: TAS216, -13°C, FL160

  • 13:58 UTC: in-cloud, close to cloud top

  • 13:59 UTC: big ice, TAS210, -11°C, FL150

  • 14:01 UTC: TAS206, -11°C, FL140, Hawkeye works

  • 14:03 UTC: windshield iced up

  • 14:04 UTC: TAS196, -6°C, FL110, big ice

  • 14:06 UTC: TAS204, -4°C, FL100

  • 14:07 UTC: TAS206, -2°C, FL090, some icing, lots of droplets in FCDP, small ice in 2DS

  • 14:09 UTC: TAS183, 0°C, FL070

  • 14:10 UTC: TAS180, 2°C, FL060, some cloud gaps in the vertical

  • 14:12 UTC: in cloud again, big drops, rain

  • 14:13 UTC: 5°C, ascent, big drops, FL040

  • 14:15 UTC: TAS163, 3°C, FL050

  • 14:16 UTC: TAS162, 1°C, FL070

  • 14:17 UTC: TAS170, -1°C, FL080, lots of crystals (columns?)

  • 14:18 UTC: TAS179, -2°C, FL090

  • 14:19 UTC: TAS187, -4°C, FL100, going a bit up to -5°C

  • 14:19 UTC: TAS188, -5°C, FL107, small and big ice on 2DS, EC overpass

  • 14:21 UTC: TAS198, -3°C, FL097

  • 14:23 UTC: TAS193, 0°C, FL079

  • 14:24 UTC: TAS192, 2°C, FL065, in cloud all the time

  • 14:25 UTC: can see ocean below, little rain, much less than before

  • 14:27 UTC: TAS190, 5°C, FL040, below cloud, can still see ocean, looks like little rain still on windshield

  • 14:29 UTC: cloud base roughly, TAS175, 3°C, FL063, completely in cloud again

  • 14:30 UTC: snowing @WP2

  • 14:31 UTC: TAS179, 1°C, FL080

  • 14:32 UTC: TAS183, -1°C

  • 14:34 UTC: 2DS not updating, but receiving bytes, no image update (took video), just doesn’t seem to see a particle right now

  • 14:34 UTC: TAS189, -4°C, FL110, FCDP updating, very small droplets (maybe that’s why nothing 2DS)

  • 14:36 UTC: TAS196, -8°C, FL131

  • 14:37 UTC: TAS198, -10°C, FL150

  • 14:37 UTC: out of cloud top, going home, 2DS updating again and seeing particles

  • 14:39 UTC: TAS205

  • 14:40 UTC: sundog to the right

  • 14:48 UTC: FL240, above cirrus, -30°C

  • 14:49 UTC: still a bit in cloud, 2DS + FCDP see something, 180kts ground speed

  • in-flight entertainment + service starts

  • 14:57 UTC: no cloud anymore, we are above it it seems

  • 15:36 UTC: in cloud during approach

Instrument status & quicklooks#

Instrument

Operational

Comment

FCDP

✅

None

2D-S

✅

None

CPI

❌

camera connection issue

CAS-DPOL

❌

CAPS computer failure

CIP

❌

CAPS computer failure

LWC Hotwire

❌

CAPS computer failure

Gopros

✅

None

Cloud situation right before start of EC leg: descending into low cloud deck with some high clouds above.

Temperature profiles for the 4 profiles while porpoising during EC overpass.

Quicklook live-view from FCDP (right) and 2DS (left) during EC overpass: lots of droplets and small+big ice.

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