1. transitioning unique NASA data and research technologies to the NWS AIRS Profile Assimilation - Case Study results Shih-Hung Chou, Brad Zavodsky Gary Jedlovec, and Bill Lapenta

2. transitioning unique NASA data and research technologies to the NWS Motivation for Profile Assimilation at SPoRT  The SPoRT Center seeks to improve short-term weather forecasts by the use of satellite-based observation.  AIRS data complement traditional upper-air observations in data-sparse regions (both ocean and land)  In contrast to AIRS radiances, profiles provide an easier assimilation method allowing regional and local end users (e.g. HUN WFO) to run NWP systems  Hyperspectral nature of AIRS sounder allows for high-resolution data

3. transitioning unique NASA data and research technologies to the NWS AIRS Specifications Aboard Aqua polar orbiter  Early afternoon equator crossing  2378 spectral channels  3.7 – 15.4 μm (650 – 2675 cm -1 )  3 x 3 footprints (50 km spatial resolution)  AMSU allows for retrievals in both clear and cloudy scenes Version 4.0 Error Estimates (Tobin et al. 2006)  0.6-1.0K over ocean (± 50 o latitude)  0.9-1.3K global ocean and land (in 1 km layers)  < 15% RH (in 2 km layers)

4. transitioning unique NASA data and research technologies to the NWS AIRS Data Quality Indicators Quality indicators (QIs) in prototype v5:  each profile contains level- specific QI  level-by-level error estimates for each T and q profile  QIs allow for the maximum amount of quality data to be assimilated  optimal use of QIs should produce an analysis that provides better initial conditions for the WRF 0700 UTC 20 November 2005 AIRS swath

5. transitioning unique NASA data and research technologies to the NWS Lessons Learned from Previous SAC 4 January, 2004  Pacific storm stalled off shore; limited its impact on land  Difficult to evaluate AIRS impact due to insufficient RAOB stations and stage IV precip data for verification  Mixed results for AIRS impact on forecast

6. transitioning unique NASA data and research technologies to the NWS Case Study: November 20-22, 2005  relevant to SPoRT interests in SEUS region  ample verification data available over the Eastern US synoptic setting  opportunity to eventually test both over-ocean and over-land AIRS profiles  comparable CONUS domain to other SPoRT WRF for easy transfer to operational applications Rapidly intensifying storm off the eastern seaboard under forecasted by GFS, NAM, and SPoRT operational WRF Case Selection Surface analysis 11/22/05 12 UTC Surface analysis 11/20/05 12 UTC Surface analysis 11/22/05 12 UTC L L L

7. transitioning unique NASA data and research technologies to the NWS Analysis and Forecast Model Configuration WRF Model Configuration  36km domain with 150x360 grid  37 vertical levels  Initialized with NAM analysis, LBC updated every 3 h ADAS Analysis Configuration  Same horizontal domain as WRF  43 vertical levels separated by 500 m  AIRS profiles are assimilated as RAOBs using QIs to determine highest quality data  use Tobin et al. (2006) for observation error and standard model errors for background Assimilation / Forecast  7h forecast used as background for ADAS L L L WRF Domain for November 2005 Case Study AIRS valid at 0700 UTC 7h FCST 00 UTC 11/20/05 00 UTC 11/22/05 Validation at 00 UTC and 12 UTC 00 UTC 11/21/05 ADAS

8. transitioning unique NASA data and research technologies to the NWS Impact of AIRS Profiles on ADAS Analysis AIRS data have an cooling impact over Atlantic, but a warming impact on land 700 hPa Temp Difference 700 hPa Dew Point Difference AIRS data have a major drying off east seaboard

9. transitioning unique NASA data and research technologies to the NWS Impact of AIRS Profiles on ADAS Analysis 07Z BKGD 07Z AIRS 07Z ADAS 20 November 2005 Wallops Island, VA  AIRS shows cooling in the lower and upper troposphere  AIRS shows drying above 900 hPa

10. transitioning unique NASA data and research technologies to the NWS Impact of AIRS Profiles on Initial Conditions 07Z BKGD 07Z AIRS 07Z ADAS 00Z RAOB 12Z RAOB  AIRS shows mid-troposphere cooling  AIRS correctly detects the moistening of 700-500 hPa layer 20 November 2005 Wallops Island, VA  AIRS shows cooling in the lower and upper troposphere  AIRS shows drying above 500 hPa  AIRS shows drying above 900 hPa AIRS can spatially and temporally fill the gap between conventional observations

11. transitioning unique NASA data and research technologies to the NWS  Control is too warm and moist at all tropospheric levels Temperature and Moisture Impact  AIRS cools T by as much as 0.5 o C (improvement) in much of troposphere; increases q bias at mid-levels  AIRS reduces RMS error in T and q at most levels

12. transitioning unique NASA data and research technologies to the NWS 6-h Cumulative Precipitation Impact  CNTL over-forecast over the low center and under forecast over TN/AL  AIRS improves forecast compared to NCEP Stage IV data in region of heaviest precipitation

13. transitioning unique NASA data and research technologies to the NWS 6-h Cumulative Precipitation Impact Bias Score  a measure of precip coverage  Precipitation under-forecasted  CNTL better at middle threshold; AIRS better at high Equital Threat Score  a measure of precip loaction  AIRS outperforms CNTL at most threshold; similar at smallest threshold CNTL AIRS Qualitative Precipitation Forecast

14. transitioning unique NASA data and research technologies to the NWS Summary AIRS Level-2 profiles provide valuable data over regions otherwise devoid of upper-air observations; they also fill the gap in time between the conventional observations Level-specific QIs for AIRS profiles allow for the assimilation of the largest volume of highest quality data AIRS data improves forecasts of T, q, and 6 h precip Future plans involving AIRS  Real-time forecasts to evaluate long-term impact  Select new case studies for in-depth analysis