COSMIC Overview and Status

Bill KuoCOSMIC Program Director

COSMIC (Constellation Observing System for Meteorology, Ionosphere and Climate) 6 microsatellites launched in April 2006

Three instruments:GPS receiver, TIP, Tri-band beacon

All six spacecraft are operating

Produced GPS RO soundings:-1.9M neutral atmospheric profiles-2.0M ionospheric profiles-1,500~ 2,300 soundings per day

1111 registered users from 52 countries

90% of the soundings delivered within 3hA Joint Taiwan-U.S. Mission FORMOSAT-3 in Taiwan

1.9 Million Profiles in Real Time4/21/06 – 8/4/2009

Presentation of first results from COSMIC/FORMOSAT-3Published inBulletin of American Meteorological Society,March 2008

Anthes et al.

GPSRO improvement southern hemisphere RMS Height Scores (Dec 15, 2006-Feb 18, 2007)

Courtesy: Sean Healy, ECMWF

COSMIC: Impact on NCEP Operation (I)• AC scores (the higher the

better) as a function of the forecast day for the 500 mb gph in Southern Hemisphere

• 40-day experiments:– expx (NO COSMIC)– cnt (operations - with

COSMIC)– exp (updated RO

assimilation code - with COSMIC)

• Many more observations• Reduction of high and low

level tropical winds error

1. COSMIC provides 8 hours of gain in model forecast skill at day 7!!!!

Courtesy: Lidia Cucurull, JCSDA/UCAR

• Skill score dropouts plague NCEP’s global model performance in Northern and Southern Hemispheres

• Dropouts are defined by 5-day anomaly correlation (AC) scores < 0.70

• For example, the 00Z Feb. 03 2008 case, using GPSRO + AMSUB + MHS data alleviated a dropout in the southern hemisphere.

SH 5-day AC scores:

GFS=0.65 (NCEP’s model)GDAS=0.69ECMWF=0.83

First guess+nodata=0.70First guess+conven=0.68First guess+conven+amsua=0.70First guess+conven+airs=0.75 First guess+conven+amsub=0.77First guess+conven+mhs=0.78First guess+conven+gpsro=0.79First guess+conven+mhs+amsub=0.78First guess+conven+gpsro+mhs+amsub=0.87

COSMIC: Impact on NCEP Operation (II)

2. COSMIC alleviates ‘dropouts’ in the Southern Hemisphere

Courtesy: Lidia Cucurull, JCSDA/UCAR

• 12 COSMIC soundings used to construct X-section along NW-SE axis through the AR• The COSMIC soundings yield cross-sectional thermodynamic structures comparable in character

and detail to previous aircraft-based dropsonde surveys.

COSMIC-Derived Cross Section of an Atmospheric River

Tropopause

Polar cold

front

Tradewindinversion

Atmosphericriver

Reverse thermalgradient - LLJ

Neiman et al. (2008), Mon. Wea. Rev.

Forecast: Verification with SSM/I

Valid at 0200 UTC 7 November 2006 on 36-km domain

No GPS

GPS Nonlocal

GPS Local

SSM/I

The difference of 24h accumulative precipitation ending at 1200 UTC 7 November 2006 as a result of assimilation of GPS RO soundings. The left panel uses the simple local observation operator, and the right panel uses the advanced nonlocal observation operator.

GPS Local – No GPS GPS Nonlocal – No GPS

Evaluate 24h Precipitation 4-km domain

An example of strong inversion layer on top of ABL

Radiosonde data23 January 200215.97S, 5.70W

RO observables modeledfrom the radiosonde data.The “step-like” structures inbending angle and refractivity

PBL study by Seregey Sokolovskiy (COSMIC) and Don Lenschow (MMM)

Distribution of heights of strong inversion layers(BAL > 1E-2 rad) over North America

Winter:- fewer strong inversion layers over continent, more over the ocean southwards- shallower ABL over continent- deeper ABL over the ocean than in Summer

Summer:most sharp inversion layers(pronounced ABL top)over the ocean and plains;less over mountains

PBL height estimated by COSMIC

PBL height averaged over 7 month period, Jan-July - 07

Mean ABL height cross-section along the line AB (left) and DC (right). Vertical lines indicate the error bars

PBL height estimated by COSMICCalifornia coast to Hawaii S. America - VOCALS region

Precision of COSMIC RO Data: FM3 vs FM4

Within 10 km

With 0.02-0.05 K precision at all vertical levels,COSMIC data areuseful to inter-calibratemeasurements from other satellites

Dry temperature difference between 2 nearby COSMIC Satellites

a b c

COSMIC data to calibrate AMSU on NOAA satellites

Ionospheric Climatology from COSMIC Data

Lei, J., S. Syndergaard, A. G. Burns, S. C. Solomon, W. Wang, Z. Zeng, R. G. Roble, Q. Wu, Y.-H. Kuo, J. M. Holt, S.-R. Zhang, D. L. Hysell, F. S. Rodrigues, and C. H. Lin, Comparison of COSMIC ionospheric measurements with ground-based observations and model predictions: preliminary results, J. Geophys. Res., 112, A07308, doi:10.1029/2006JA012240, 2007.

Neutral Winds derived from COSMIC Data

Luan, X., and S. C. Solomon, Meridional winds derived from COSMIC radio occultation measurements in winter, J. Geophys. Res., in press, 2008.

COSMIC-II Planning

• RO has shown positive impacts on weather prediction, climate monitoring.

• An opportunity exists now to begin a robust, operational RO mission.

• Mitigate loss of climate observing capability on NPOESS.

• Major contribution to operational space weather.

• Taiwan and U.S. are collaborating on a COSMIC-II plan of 12-satellite constellation.

• The planned first launch of COSMIC-II is expected in 2014 time frame.

Two Possible Configurations for COSMIC-II:

• Option A: – 8 satellites placed at 72 degree inclination angle– 4 satellites placed at 24 degree inclination angle

• Option B:– 12 satellites placed at 72 degree inclination angle

Distribution of RO soundings in a day

FORMOSAT-3/COSMIC COSMIC-IIA COSMIC-IIBG A B

Different color shows availability of RO soundings at different hours of the day.

Typhoon Forecast Improvements based on observing system simulation experiments

• We perform two-day data assimilation, followed with three-day forecast for COSMIC, COSMIC-IIA, and COSMIC-IIB, in an observing system simulation experiment (OSSE) study.

• Compared with the Control (without RO data) COSMIC-II gives far superior results (in terms of % improvement).

Intensity forecast Track forecast

COSMIC 8.1 25.0

COSMIC-IIA 43.3 79.1

COSMIC-IIB 26.0 39.5

U.S. Regional NetworkCONUS network

Caribbean network

NOAA NGS CORS

IGS Network

SUOMINET

Processing

UNIDATALDM

UNAVCOPBO

Near Rea-time

ZTD / PWVResearchForecast

Global network

(Daily processing)

Hurricane Dean Forecast

About 20 hPa improvement