Atmospheric data for Arctic modeling

John Walsh

International Arctic Research Center

University of Alaska, Fairbanks

Arctic System Modeling Workshop, Montreal, July 2009

Three categories of atmospheric observations:

1) Routine measurements for input to NWP models

2) Special observing networks

3) Short-duration field campaigns

Three categories of atmospheric observations:

1) Routine measurements for input to NWP models

2) Special observing networks

3) Short-duration field campaigns

+

Value-added products: reanalyses

gridded fields (e.g., CRU)

Polar Pathfinder products

Routine measurements – in some respects, the Arctic is well-covered

surface synoptic network rawinsonde network buoy, ship reports aircraft reports satellite measurements (profiles of T, q, wind)

Archived in reanalysis ingest data banks

(e.g., PREPBUFR files at NCAR)

Surface station observations Upper-air rawinsonde observations

Surface ship and ocean buoy reports

7-days

Reports from commercial, military, and reconnaissance sources

7-days: 01/01/2003 - 01/07/2003

Satellite-derived temperatures

7-days

Winds derived from satellite observed cloud drift analysis

7-days

6-hour accumulated

observations:

red: surface station

slate blue: upper-air

yellow: sat. temp.

green: sat. wind

violet: aircraft

sky blue: ship

01/01/2003

00Z

6-hour accumulated

observations:

red: surface station

slate blue: upper-air

yellow: sat. temp.

green: sat. wind

violet: aircraft

sky blue: ship

01/01/2003

06Z

6-hour accumulated

observations:

red: surface station

slate blue: upper-air

yellow: sat. temp.

green: sat. wind

violet: aircraft

sky blue: ship

01/01/2003

12Z

6-hour accumulated

observations:

red: surface station

slate blue: upper-air

yellow: sat. temp.

green: sat. wind

violet: aircraft

sky blue: ship

01/01/2003

18Z

SID=BAW269 , YOB= 60.00, XOB=340.00, ELV=10058, DHR=-0.550, RPT= 17.450, TCOR=0, TYP=130, TSB=0, T29= 41, ITP=99, SQN= 26PROCN= 0, SAID=***RCT= 18.08, PCAT=*****, POAF=***, DGOT=***---------------------------------------------------------------------------------------------- level 1 obs qmark qc_step rcode fcst anal oberr category ----------------------------------------------------------------------------------------------PRESSURE (MB) 262.0 2. PREPRO ***** ******** ******** ******** 6.SP HUMIDITY(MG/KG) ******** ****** ***** 35.0 35.0 ******** 6.TEMPERATURE (C) -62.0 1. PREPACQC 17. -61.1 -60.9 1.7 6.TEMPERATURE (C) -62.0 2. PREPRO ***** -61.1 -60.9 1.7 6.HEIGHT (METERS) 10058.0 2. PREPRO ***** 9708.0 9724.0 ******** 6.U-COMP WIND (M/S) 4.4 1. PREPACQC 17. -2.3 1.8 3.6 6.U-COMP WIND (M/S) 4.4 2. PREPRO ***** -2.3 1.8 3.6 6.V-COMP WIND (M/S) 2.6 1. PREPACQC 17. 4.8 2.1 3.6 6.V-COMP WIND (M/S) 2.6 2. PREPRO ***** 4.8 2.1 3.6 6.WIND DIR (DEG) 240.0 ****** PREPRO ***** ******** ******** ******** 6.WIND SPEED (KNOTS) 10.0 ****** PREPRO ***** ******** ******** ******** 6.

Sample PrepBUFR observations:

SID=48582 , YOB= 82.85, XOB=194.99, ELV= 0, DHR= 1.883, RPT= 19.883, TCOR=0, TYP=180, TSB=*, T29=562, ITP=99, SQN= 203PROCN= 2, SAID=***PMO=******, PMQ=**---------------------------------------------------------------------------------------------- level 1 obs qmark qc_step rcode fcst anal oberr category ----------------------------------------------------------------------------------------------PRESSURE (MB) 988.2 2. PREPRO ***** 987.6 987.4 1.6 0.SP HUMIDITY(MG/KG) ******** ****** ***** 234.0 239.0 ******** 0.TEMPERATURE (C) -33.3 2. PREPRO ***** -32.8 -32.8 2.5 0.HEIGHT (METERS) 0.0 2. PREPRO ***** -4.0 -5.0 ******** 0.

PrepBUFR dataQuality Control Flags

0) Keep (always assimilate)1) Good2) Neutral or not checked (default) -- e.g.,

IAOBP T and P obs are flagged as QC=23) Suspect4) Rejected (don’t assimilate)

** Rejected obs. have an additional flag layer indicating justification (e.g., conflicts with a pre-existing QC=0; threshold test failure, etc.)

2) Examples of special observing networks

• International Arctic Buoy Network

( + Russian NP stations)• Greenland automated weather stations• Trace gas/chemical sampling (NOAA CMDL)• Baseline Surface Radiation Network (BSRN), ARM• International Arctic System for Observing the

Atmosphere (IASAO)

Tiksi, Russia

Alert, Canada

Barrow, Alaska

Eureka, Canada

Summit, Greenland

Ny-Alesund, Svalbard

IASOA Target Observatories

IASAO

IASAO: International Arctic System for Observing the Atmosphere

3) Short-duration field programs

-- process studies for algorithm development, model validation

• SHEBA• ATLAS, LAII Flux Study• ARM field campaigns• OASIS• IPY cruises

… others

Problem areas

• Precipitation, especially solid precip (snowfall, depth, water equivalent)

• Clouds

• Aerosols

• … others