1. Preliminary Analyses of S-Pol’s Refractivity Field
Tammy M. Weckwerth and Crystalyne Pettet
NCAR/ATD
IHOP Science Workshop, Boulder, March 2003

2. Our Objectives
Evaluate representativeness of low-level refractivity retrieval
Fixed and mobile mesonets
Evaluate layer over which refractivity retrieval is representative
Aircraft in situ measurements
SRL vertical profiles

3. IHOP_2002

4. S-Pol Refractivity Retrieval
Variations in q, T and p
Boundary detection
Advection
QPF, CI, ABL, bores and instrumentation
dryline
dryline
cool/moist
warm/dry

5. 22 May 2002
Reflectivity
Refractivity
warm/dry
cool/moist

6. S-Pol Surface Station Courtesy of Rita Roberts (NCAR)
& Fleur Couvreux (Meteo/France)

7. 22 May UTC
P-3
MM6

8. 22 May 2002 2000 UTC MM6 Small N variation
Corresponding small q, T variations
NRL P-3
Strong q correlation
Weaker inverse T relationship

9. 22 May UTC
MM6
MM8

10. 22 May 2002 2200 UTC MM6 Comparable N, q trends
Abrupt q gradients not in N (20m vs. 4 km)
Inverse T relationship
MM8
Strong q correlation
Weaker inverse T relationship

11. 22 May UTC
UWKA

12. 22 May 2002 2209 UTC UWKA Mid CBL Strong q, N correlation
Weak inverse T relationship
N gradient is wider than fine line

13. 22 May UTC
UWKA
MM7

14. 22 May UTC
MM7
q and inverse T trends are more abrupt than N gradient
N gradient and fine line are comparable
UWKA
q and inverse T trends are more abrupt than N gradient
N gradient and fine line are comparable

15. NASA/GSFC Scanning Raman Lidar
Courtesy of Belay Demoz (NASA/GSFC)

16. Summary
Evaluate representativeness of low-level refractivity retrieval
Strong direct relationship with surface q measurements
Weaker inverse relationship with surface T measurements
Evaluate layer over which refractivity retrieval is representative
Aircraft measurements suggest direct relationship with CBL q measurements and inverse T relationship
SRL comparison suggests direct relationship with q during significant boundary passage but no N variation during other boundary layer circulation passages

17. Ongoing Work
Evaluate representativeness of low-level refractivity retrieval
Fixed and mobile mesonets
Plan to: Add GPS intercomparisons
Plan to: Add DRI MMR intercomparisons
Evaluate layer over which refractivity retrieval is representative
Aircraft in situ measurements
SRL intercomparisons
Plan to: Add AERI vertical profiles
Plan to: Add Sounding & Dropsonde comparisons
Plan to: Add horizontal and vertical pointing airborne DIAL
Plan to: Add TAOS intercomparisons
Possibly add: MIPS profiling radiometer intercomparisons
Plan to: Evaluate two more days

18. AERI measurements

19. Mobile mesonet measurements

20. AERI measurements

21. Mobile mesonet measurements