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 observationsUpper-air rawinsonde observations

Surface ship and ocean buoy reports 7-days

Reports from commercial, military, and reconnaissance sources 7-days: 01/01/ /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/ Z

6-hour accumulated observations: red: surface station slate blue: upper-air yellow: sat. temp. green: sat. wind violet: aircraft sky blue: ship 01/01/ Z

6-hour accumulated observations: red: surface station slate blue: upper-air yellow: sat. temp. green: sat. wind violet: aircraft sky blue: ship 01/01/ Z

6-hour accumulated observations: red: surface station slate blue: upper-air yellow: sat. temp. green: sat. wind violet: aircraft sky blue: ship 01/01/ Z

SID=BAW269, YOB= 60.00, XOB=340.00, ELV=10058, DHR=-0.550, RPT= , TCOR=0, TYP=130, TSB=0, T29= 41, ITP=99, SQN= 26 PROCN= 0, SAID=*** RCT= 18.08, PCAT=*****, POAF=***, DGOT=*** level 1 obs qmark qc_step rcode fcst anal oberr category PRESSURE (MB) PREPRO ***** ******** ******** ******** 6. SP HUMIDITY(MG/KG) ******** ****** ***** ******** 6. TEMPERATURE (C) PREPACQC TEMPERATURE (C) PREPRO ***** HEIGHT (METERS) PREPRO ***** ******** 6. U-COMP WIND (M/S) PREPACQC U-COMP WIND (M/S) PREPRO ***** V-COMP WIND (M/S) PREPACQC V-COMP WIND (M/S) PREPRO ***** WIND DIR (DEG) ****** 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= , TCOR=0, TYP=180, TSB=*, T29=562, ITP=99, SQN= 203 PROCN= 2, SAID=*** PMO=******, PMQ=** level 1 obs qmark qc_step rcode fcst anal oberr category PRESSURE (MB) PREPRO ***** SP HUMIDITY(MG/KG) ******** ****** ***** ******** 0. TEMPERATURE (C) PREPRO ***** HEIGHT (METERS) PREPRO ***** ******** 0.

PrepBUFR data Quality Control Flags 0) Keep (always assimilate) 1)Good 2)Neutral or not checked (default) -- e.g., IAOBP T and P obs are flagged as QC=2 3)Suspect 4)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, CanadaBarrow, 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