Nowcasting Airport Winter Weather – AVISA Tests

During AIRS II

Presentation by

George A. Isaac

Cloud Physics and Severe Weather Research Division

Environment Canada

AVISA – Airport Vicinity Icing and Snow AdvisorAIRS – Alliance Icing Research Study

Co-Authors & Funding Agencies

• Monika Bailey, Stewart Cober, Norman Donaldson, Ismail Gultepe, Norbert Driedger, David Hudak, Anna Glazer, Janti Reid, Peter Rodriguez, and J. Walter StrappEnvironment Canada, Toronto

• Alexei Korolev Skytech Research Inc, Richmond Hill• Frederic Fabry

McGill University, Montreal

• Funds from Transport Canada, FAA, SAR/NIF, NRC/IAR, CRC, McGill, CFCAS, NSERC

Problems Associated with Airport Winter Weather

• Ice forming on wings of aircraft requiring de-icing

• Reduced visibility

• Low ceilings

• Runway icing and snow removal

• In-flight icing during takeoff and landing

• Extreme cold temperatures

St

Joh

n's

Hal

ifax

Go

ose

Iqal

uit

Qu

ebec

Cit

y

Do

rval

Mir

abel

Ott

awa

To

ron

to

Su

db

ury

Th

un

der

Bay

Win

nip

eg

Cal

gar

y

Ed

mo

nto

n

Cra

nb

roo

k

Van

cou

ver

Wh

iteh

ors

e

Yel

low

knif

e

Airport Location

0

10

20

30

An

nu

al F

req

ue

nc

y o

f O

ccu

rre

nc

e (

%)

H azard Type

Frost

Freezing Fog

W et Snow

D ry Snow

Snow Pelle ts

B low ing Snow

Freezing R ain

Freezing D rizzle

Ice Pelle ts

Hazardous Hours at Canadian Airports

Stuart and Isaac, 1994: ICAO Journal

Alliance Icing Research Study II• A large international research program

(participants from 25 organizations from N.A. and Europe, gov’t and university sectors)

• Lead by MSC• Conducted in the Ottawa-Mirabel region 3 Nov 2003

to 13 Feb 2004• Focus on aviation meteorology research,

nowcasting, aircraft icing, cloud processes• Web site http://airs-icing.org/ (Science Plan, Data

access, publications, etc)• Endorsed by Aircraft Icing Research Alliance

(AIRA) and WWRP Aircraft In-Flight Icing Project (AIFI)

• Five (5) research aircraft involved• Three (3) different Nowcasting systems (MSC,

NASA, NCAR/NOAA)• Data currently being quality controlled and

archived• Project Workshop was conducted at Mt. Tremblant,

9-10 November• Special Session at AIAA in Reno in January/05

Participating Organizations

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

Nov03 Nov08 Nov13 Nov18 Nov23 Nov28 Dec03 Dec08 Dec13 Dec18

PO

SS

Pre

cip

itat

ion

Rat

e [m

m/h

r]

-20

-16

-12

-8

-4

0

4

8

12

16

20

Su

rfac

e T

emp

erat

ure

[d

eg C

]

POSS Snow

POSS Rain

Obs ZR/ZL

Convair-580

Twin Otter

C130

Citation

ER2

UAS

Temp 6-hr Avg

Precip 6-hr Avg

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

Jan18 Jan23 Jan28 Feb02 Feb07 Feb12

PO

SS

Pre

cip

itat

ion

Rat

e [m

m/h

r]

-40

-35

-30

-25

-20

-15

-10

-5

0

5

10

Su

rfac

e T

emp

erat

ure

[d

eg C

]

POSS Rain

POSS Snow

Obs ZR/ZL

Convair-580

UAS

Temp 6-hr Avg

Precip 6-hr Avg

IOP1

IOP2

AIRS II Precipitation & Flight Summary over Mirabel

AVISA Input Parameters

GOES SatellitePOSS, HP &

Met Station

Vertically Pointing Radar (VPR)

Radiometers HIMAP & GEM Models

MSC-AVISAAirport Vicinity Icing and Snow

Advisor

Ic ingInte ns R

Ic ingO c c u rR

C T T G

S k y C G

C T P ha s e G

S fc T S

S fc P c p T y p e S

S k y C S

S fc P c p Inte ns S

S fc W ind S

C e ilingS

4 D -T M

4 D -W ind M

4 D -C lo u d M

4 D -P re c ip M

4 D -Ic ingM

T P ro file A

P c p T ra c k A

F ro ntP o s AT o p o F e a tu re A

P c p E xte ntA

F rzLv lD R

P c p O c c u rD R

P c p T ra c k D R

P c p Inte ns D R

P c p E xte ntD R

C e ilingC

P c p Inte ns H

P c p T y p e P ro file V

F rzLv lV

Ic ingO c c u rP R

Ic ingInte ns P R

S fc P c p T y p e P

S fc P c p O c c u rP

S fc P c p Inte ns P

R ad io m eter

G O E SS ate llite

C eilo m eter M o d el

S u rface O b s

D o p p ler R ad ar

P irep 's

V P R

H o t P la teP rec ip P O S S

A U R O R A

ARE

SKIES CLEAR?

SLW IS ASSUMED FALSE FOR ALL HEIGHTS

SLW IS INCONCLUSIVE

SLW IS ASSUMED FALSE AT THAT HEIGHT

DERIVE BEST GUESS CTH

DERIVE BEST GUESS CBH

IS THERE LIQUID PRECIPITATION?

IS THE

RADIOMETER LWP > 0C AND

GEM MODEL TEMP < 0C?

SLW IS ASSUMED TRUE FOR THAT HEIGHT

YES

YES

NO

NO

NO

YES

Supercooled Liquid Water (SLW)

METHOD 1

FOR HEIGHTS BETWEEN

BEST GUESS CT & CB

Case Study: February 6, 2004 1900-2210 UTC

0

1

2

3

4

5

6

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

-50 -45 -40 -35 -30 -25 -20 -15 -10 -5 0

Nevz IWC

Nevz LWC

2D Sphere Frac

Aircraft Temp

Sounding 1949Z

HIMAP Temp Avg

TPR Temp Avg

0

1

2

3

4

5

6

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

HIMAP LWC Avg

VPR LWC Avg

TPR LWC Avg

Temperature [deg C]

LWC [g/m3] and Sphere Particle Fraction

Alti

tude

[km

]

LWC [g/m3] or [g/kg] for HIMAP

M+S Icing

YMX

February 6, 2004 - 19 UTC in the vicinity of YMX

HIMAP Supercooled LWP & GOES Icing

0.03 cm

0.03 cm

0.04 cm

Current Time: 2004-02-06 19:00Z

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

13 14 15 16 17 18 19 20 21 22 23 00 01

Observation Time (GMT)

Pre

cip

Ra

te [

mm

/hr]

HIMAP RR

GEM RR

Hot Plate 1

Hot Plate 2

POSS ZR

POSS Snow Type

WMN Snow

HIMAP RR - Future

GEM RR - Future

WMN Snow Pt Fcst

Current Time: 2004-02-06 19:00Z

0.00

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.10

13 14 15 16 17 18 19 20 21 22 23 00 01

Observation Time (GMT)

Inte

gra

ted

Liq

uid

Wat

er [

cm]

HIMAP IC

GEM IC

TP3000 Radiometer

WVR1100 Radiometer

HIMAP IC - Future

GEM IC - Future

YMX

GOES ICING @ 1902

Precipitation Observations & Forecast at YMX LWP Observations & Forecast at YMX

HIMAP Total Precipitation Rate and Radar

0.5 mm/hr

0.9 mm/hr

> 0.5 mm/hr

20 km

HIMAP Total Precipitation Rate and Radar

0.5 mm/hr

0.9 mm/hr

> 0.5 mm/hr

20 km

HIMAP Supercooled LWP & GOES Icing

0.03 cm

0.03 cm

0.04 cm

YMX

GOES ICING @ 1902

Current Time: 2004-02-06 19:00Z

0.00

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.10

13 14 15 16 17 18 19 20 21 22 23 00 01

Observation Time (GMT)

Inte

gra

ted

Liq

uid

Wat

er [

cm]

HIMAP IC

GEM IC

TP3000 Radiometer

WVR1100 Radiometer

HIMAP IC - Future

GEM IC - Future

Current Time: 2004-02-06 19:00Z

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

13 14 15 16 17 18 19 20 21 22 23 00 01

Observation Time (GMT)

Pre

cip

Ra

te [

mm

/hr]

HIMAP RR

GEM RR

Hot Plate 1

Hot Plate 2

POSS RR

WMN Snow

HIMAP RR - Future

GEM RR - Future

WMN Snow Pt Fcst

Current Time: 2004-02-06 19:00Z

0.00

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.10

13 14 15 16 17 18 19 20 21 22 23 00 01

Observation Time (GMT)

Inte

gra

ted

Liq

uid

Wat

er [

cm]

HIMAP IC

GEM IC

TP3000 Radiometer

WVR1100 Radiometer

HIMAP IC - Future

GEM IC - Future

Observed Data: 2004-02-06 13:00Z to 2004-02-07 01:00Z

0.00

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.10

13 14 15 16 17 18 19 20 21 22 23 00 01

Observation Time (GMT)

Inte

gra

ted

Liq

uid

Wat

er [

cm] HIMAP IC

GEM IC

TP3000 Radiometer

WVR1100 Radiometer

Current Time: 2004-02-06 19:00Z

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

13 14 15 16 17 18 19 20 21 22 23 00 01

Observation Time (GMT)

Pre

cip

Ra

te [

mm

/hr]

HIMAP RR

GEM RR

Hot Plate 1

Hot Plate 2

POSS RR

WMN Snow

HIMAP RR - Future

GEM RR - Future

WMN Snow Pt Fcst

Observed Data: 2004-02-06 13:00Z to 2004-02-07 01:00Z

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

13 14 15 16 17 18 19 20 21 22 23 00 01

Observation Time (GMT)

Pre

cip

Ra

te [

mm

/hr]

HIMAP RR

GEM RR

Hot Plate 1

Hot Plate 2

POSS RR

WMN Snow

Model/Radiometer Comparison

Liquid Water Paths Water Vapour Paths

Profiling Radiometer LWP [cm] Profiling Radiometer WVP [cm]

HIM

AP

LW

P [

cm]

HIM

AP

WV

P [

cm]

Comparison with HIMAP During AIRS II

Parameter Instrument Hit Rate FAR TSS

Liquid Water Path

Profiling

Radiometer

HIMAP 0.54 0.11 0.43

Cloud Occurrence

Ceilometer HIMAP 0.96 0.69 0.27

Precipitation

> 0 mm/hr

Hot Plate 1 HIMAP 0.78 0.17 0.61

Precipitation

> 2 mm/hr

Hot Plate 1 HIMAP 0.42 0.01 0.41

Cloud Base on November 4, 2003 12 UTC+ 24 Hours

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

12 13 14 15 16 17 18 19 20 21 22 23 00 01 02 03 04 05 06 07 08 09 10 11

Observation Time (GMT)

Clo

ud

Ba

se

[k

m]

Obs FZ Precipitation

GEM NU

Ceilometer

Orange marks when the YMX observerreported ZR

November 4-5, 2003: Freezing Rain Event

Time series data contain a change in model runs at 00 Z

Surface Temperature on November 4, 2003 12 UTC+ 24 Hours

-5.0

-4.0

-3.0

-2.0

-1.0

0.0

1.0

2.0

3.0

4.0

5.0

12 13 14 15 16 17 18 19 20 21 22 23 00 01 02 03 04 05 06 07 08 09 10 11

Observation Time (GMT)

Te

mp

[C

] o

r P

rec

ip [

mm

/hr]

Obs FZ Precipitation

GEM Screen (TJ)

Campbell Met Stn

POSS Precip Rate

POSS Snow Type

POSS reports mainly rain type Wx

Conclusions

• AIRS II produced an excellent data set to develop and test airport systems to detect winter weather, with emphasis on icing and snow.

• Although weaknesses in some sensors and models were documented, a good system will use the strengths from various potential input components to produce reliable and accurate detection and forecast methods.

• Other aspects such as SLD formation, aircraft response to icing, and cloud characterization measurements also studied but not reported here.

TAMDAR Data GLFE (Great Lakes Fleet

Experiment) is a 12-month project started in Jan 2005 that is testing tropospheric AMDAR systems aboard 64 aircraft in the Great Lakes region

TAMDARs also measure RH, icing and turbulence

Graph shows TAMDAR icing and temperature data collected in the vicinity of Pearson on Aug 31 2005

GLFE-AIRDAT TAMDAR Data on August 31, 2005Between 10-15 UTC within ~100 mile radius of YYZ

0

1

2

3

4

5

6

7

8

-15 -10 -5 0 5 10 15 20

Temperature (C)

Alt

itu

de

[k

m]

Temperature

Heights with No Icing

Heights with Icing

Questions?