Update on winds derived from Update on winds derived from MODISMODIS

Lars Peter Riishojgaard, John Wu,Lars Peter Riishojgaard, John Wu,Meta SienkiewiczMeta Sienkiewicz

Global Modeling and Assimilation OfficeGlobal Modeling and Assimilation Office

Lidar Working Group, Miami, February 6-9 2007Lidar Working Group, Miami, February 6-9 2007

OverviewOverview

• Context of current studyContext of current study

• Data assimilation systemData assimilation system

• ResultsResults

• DiscussionDiscussion

Lidar Working Group, Miami, February 6-9 2007Lidar Working Group, Miami, February 6-9 2007

MODIS winds now and in the futureMODIS winds now and in the future

Good results obtained by many centers with assimilating polar winds from Good results obtained by many centers with assimilating polar winds from MODISMODIS– Used operationally in all major global forecast systemsUsed operationally in all major global forecast systems

No current plans for what comes after MODIS (2008+)No current plans for what comes after MODIS (2008+)– Polar winds is not an NPOESS EDRPolar winds is not an NPOESS EDR– No water vapor channel on VIIRSNo water vapor channel on VIIRS

Unlikely to happen before 2020Unlikely to happen before 2020

– No water vapor channel on METOP/AVHRRNo water vapor channel on METOP/AVHRR Unlikely to happen before 2017/18Unlikely to happen before 2017/18

– Limited coverage from LEOLimited coverage from LEO– Real-time delivery of multi-temporal imagery products from LEO is Real-time delivery of multi-temporal imagery products from LEO is

difficult/expensivedifficult/expensive MODIS winds generally arrive 4-6 hours after real time when using bent MODIS winds generally arrive 4-6 hours after real time when using bent

pipepipe

Lidar Working Group, Miami, February 6-9 2007Lidar Working Group, Miami, February 6-9 2007

Community activitiesCommunity activities

Broad scientific and operational interest in high-latitudfe winds and Broad scientific and operational interest in high-latitudfe winds and other multitemporal imagery applicationsother multitemporal imagery applications– Operational NWP community voicing strong supportOperational NWP community voicing strong support

WMO recommendation to the space agencies to pursue high-latitude water vapor WMO recommendation to the space agencies to pursue high-latitude water vapor winds with timely delivery in the post-MODIS era (WMO CBS ET/ODDRGOS)winds with timely delivery in the post-MODIS era (WMO CBS ET/ODDRGOS)

– NESDIS/JPL study of imaging NESDIS/JPL study of imaging MEO constellationMEO constellation targeting polar winds targeting polar winds

– NOAA/NESDIS has repeatedly stated interest in and support for the NOAA/NESDIS has repeatedly stated interest in and support for the Molniya Molniya Orbit ImagerOrbit Imager mission proposal developed by Goddard mission proposal developed by Goddard

– CSA launching pre-Phase A study of a Molniya-like communications systemCSA launching pre-Phase A study of a Molniya-like communications system– ESA may start pre-Phase A study of a Molniya imaging mission within the ESA may start pre-Phase A study of a Molniya imaging mission within the

next year funded by Finland, Canada, Germany and Denmarknext year funded by Finland, Canada, Germany and Denmark– Russian consortium led by Roshydromet preparing a Molniya orbit imaging Russian consortium led by Roshydromet preparing a Molniya orbit imaging

proposal (GEOSS context?)proposal (GEOSS context?)

Lidar Working Group, Miami, February 6-9 2007Lidar Working Group, Miami, February 6-9 2007

Building the case for a MODIS winds Building the case for a MODIS winds follow-onfollow-on

NESDIS and GSFC collaborating on economic assessment of polar NESDIS and GSFC collaborating on economic assessment of polar winds impactwinds impact– ““Orbit neutral” assessment of the expected economic impact of Orbit neutral” assessment of the expected economic impact of

having feature tracking winds (cloud and water vapor) available having feature tracking winds (cloud and water vapor) available over entire NHover entire NH

– G. Dittberner, L. P. Riishojgaard, MitretekG. Dittberner, L. P. Riishojgaard, Mitretek Since both Molniya and MEO will provide increased coverage over Since both Molniya and MEO will provide increased coverage over

what is possible from LEO, the MODIS winds results can be used to what is possible from LEO, the MODIS winds results can be used to obtain a lower bound on the expected impactobtain a lower bound on the expected impact– Hurricane track forecasting (NCEP/JCSDA diagnostics)Hurricane track forecasting (NCEP/JCSDA diagnostics)– Low-level temperature over the lower 48 (this study)Low-level temperature over the lower 48 (this study)– Jet-stream forecasts (this study)Jet-stream forecasts (this study)

Goddard Space Flight Center

“Use or disclosure of these data is subject to the restriction on the title page of this document”

Upper air mass observations (AMSU; 6 hours)

Lidar Working Group, Miami, February 6-9 2007Lidar Working Group, Miami, February 6-9 2007

Goddard Space Flight Center

“Use or disclosure of these data is subject to the restriction on the title page of this document”

GWOS Coverage

• Around 600 radiosonde stations (black) provide data every 12 h

• GWOS (blue) would provide ~3200 profiles per day

6-hour winds coverage, 4 LEO’s

Apogee winds coverage, Molniya

Molniya OSSE(Observing system simulation experiment)

GEOS-4; Atlas et al.

Forecast improvement over North America, 48 cases

13.2  

43.6 66.5 94.9 102.8 157.1 227.9 301.1 Cntrl

11.4 34.8 60.4 82.6 89.0 135.3 183.0 252.0 Cntrl + MODIS

74 68 64 61 52 46 39 34 Cases (#)

00-h 12-h 24-h 36-h 48-h 72-h 96-h 120-h Time

AVERAGE HURRICANE TRACK ERRORS (NM) 2004 ATLANTIC BASIN

table courtesy of Le Marshall et al.; results compiled by Qing Fu Liu.

Lidar Working Group, Miami, February 6-9 2007Lidar Working Group, Miami, February 6-9 2007

Assimilation systemAssimilation system

• GEOS-5 GEOS-5 • Finite volume model developed by DAO/GMAOFinite volume model developed by DAO/GMAO• GSI analysis developed jointly with NCEP/EMCGSI analysis developed jointly with NCEP/EMC

• Pre-operational version (GEOS-5 tag beta10p4)Pre-operational version (GEOS-5 tag beta10p4)• Forecast error covariance statistics still subject to tuningForecast error covariance statistics still subject to tuning

Lidar Working Group, Miami, February 6-9 2007Lidar Working Group, Miami, February 6-9 2007

ExperimentsExperiments

• Jan/Feb 2006 (30 forecast cases)Jan/Feb 2006 (30 forecast cases)

• All NESDIS MODIS winds includedAll NESDIS MODIS winds included

• Horizontal resolution 1 by 1 ¼ degreesHorizontal resolution 1 by 1 ¼ degrees

• Verification carried out against self and NCEP Verification carried out against self and NCEP operational analysis operational analysis

Lidar Working Group, Miami, February 6-9 2007Lidar Working Group, Miami, February 6-9 2007

Lidar Working Group, Miami, February 6-9 2007Lidar Working Group, Miami, February 6-9 2007

Lidar Working Group, Miami, February 6-9 2007Lidar Working Group, Miami, February 6-9 2007

Lidar Working Group, Miami, February 6-9 2007Lidar Working Group, Miami, February 6-9 2007

Lidar Working Group, Miami, February 6-9 2007Lidar Working Group, Miami, February 6-9 2007

Lidar Working Group, Miami, February 6-9 2007Lidar Working Group, Miami, February 6-9 2007

DiscussionDiscussion

• MODIS winds add skill in all regions and for all variablesMODIS winds add skill in all regions and for all variables

• Consistently 15-20% reduction in North Atlantic tropical cyclone track Consistently 15-20% reduction in North Atlantic tropical cyclone track error throughout the forecast rangeerror throughout the forecast range

• A few hours of added skill in the 500 hPa height field at the five day A few hours of added skill in the 500 hPa height field at the five day forecast rangeforecast range

• Roughly a 10% reduction in the RMS error of the zonal wind Roughly a 10% reduction in the RMS error of the zonal wind component at flight levels in the North Atlantic corridorcomponent at flight levels in the North Atlantic corridor

• Small but positive contribution to the low-level CONUS temperature Small but positive contribution to the low-level CONUS temperature forecastforecast

Lidar Working Group, Miami, February 6-9 2007Lidar Working Group, Miami, February 6-9 2007

Discussion (II)Discussion (II)

Remarkable contribution in spite ofRemarkable contribution in spite of– Sparse coverage (no overlap with GEO)Sparse coverage (no overlap with GEO)– Infrequent imaging (~100 minute repeat rate)Infrequent imaging (~100 minute repeat rate)– Difficult viewing geometryDifficult viewing geometry– No direct influence on the forecast initial No direct influence on the forecast initial

conditions in the tropical cyclone studyconditions in the tropical cyclone study Relatively few MODIS wind vectors meet the NCEP Relatively few MODIS wind vectors meet the NCEP

operational data cut-offoperational data cut-off

Lidar Working Group, Miami, February 6-9 2007Lidar Working Group, Miami, February 6-9 2007

Future plansFuture plans

Further improvement in data selection and quality Further improvement in data selection and quality controlcontrol– More data analyzedMore data analyzed– EE (John Le Marshall)EE (John Le Marshall)

Additional diagnosticsAdditional diagnostics

Test different seasons, different periodsTest different seasons, different periods

Results to be forwarded to NESDIS/Mitretek for Results to be forwarded to NESDIS/Mitretek for inclusion in economic impact assessment reportinclusion in economic impact assessment report