Discussion Document I-LEAPS Meeting Paris, France October 16-18, 2002 David R. Fitzjarrald

1. Discussion Document I-LEAPS Meeting Paris, France October 16-18, 2002 David R. Fitzjarrald Jungle Research Group: {Ricardo Sakai, Ralf Staebler, Matt Czikowsky, Alex Tsoyreff} Atmospheric Sciences Research Center University at Albany, SUNY US of A

2. Philosophical Reynolds decomposition: • results to be presented as: ‘obvious’ ‘novelty’ Observational limitations: • No tower is in the right place. • No aircraft flies for sufficient time • No satellite really measures fluxes • the integral scale for innovation….. • Argument by anecdote is no longer sufficient ...but it was good enough for Taylor & Richardson ...example of the large eddies over canopy •

3. Surface-atmosphere exchanges: The surface layer idealization & improvements • What do we want to know, really? ‘point’ measurements are sometimes the point using weather stations for climate observation... • How to reconcile the differences between what we measure & what we model grid averages ‘Fine scale’ landscape structure • Kansas & then what? what is the zo of the Appalachian mountains? • Patchy terrain: topographic, land type roughness, H, LE, FCO2, Fs • How much detail is needed to describe canopies? is the problem only to deal with vertical exchanges?

4. Limitations of modeling--ex: vegetation “People think that trees come from the ground, but that’s not so. Trees come from the air.” Richard Feynman Green slime approach. “In spite of the seeming inappropriateness of describing photosynthesis of a 50 m tall forest canopy by radiation penetration through a green slime, a convincing intuitive argument can be forged…..” Campbell and Norman Introduction to Environmental Biophysics p.8.

5. Types of modeling: • what to do when we know the rules (almost): DNS, LES example of CBL growth • …when we think we know the rules: SL reactive chemistry…. • what to do when we have only clues, but we cannot measure All the critical variables (we make things up; zombie parameters…) SVAT & PILPS, AMIP • after we just give up on modeling: nudging, controlling boundaries example of the ‘cold bias’ in regional climate models

6. Measurements near the earth’s surface…. Curiously, many recent innovations in surface- and boundary-layer Meteorology are being stimulated by global change studies….. The commonly accepted Monin-Obukhov flux-gradient relations for the atmospheric surface layer must be modified in volumes in which mass disappears (by chemical reaction), or in regions of relatively enhanced turbulent transports (as in a roughness sublayer), or when mixing is not continuous (at night, in canopies).

7. Energy balance, a fundamental problem. Easy to imagine, hard to demonstrate.

8. "The microclimate of the surface layer can be strongly affected by turbulent flux divergence."

9. Flux divergence: vertical, chemical Tony Delany’s sketch of the observational setup at Norwich -- 1982 The principal results from Fitzjarrald and Lenschow (1983) trying to figure out the Norwich observations.

10. Turbulence and chemical reaction in the convective surface layer, 1983 style. SLACE experiment in Colorado. (some things we never published, And why……)

11. The simple O3-NO2-NO “smog” reaction lends itself to a geometrical interpretation. Chemical equilibrium surface…. Mixing line

12. A subset of the many studies published on sfc layer chemistry. (my apologies to other worthy candidates here--the only purpose is to bash (gently) overemphasis on modeling.

13. Vertical flux divergence: Harvard Forest/Worcester MA Fitzjarrald et al. (2001)

14. Leaf out Surface climatic data; Likelihood of clouds; Role of entrainment

15. 1946 CBL structure has been well understood for a long time…. 1893

16. 1942

17. 2001 ALB sondagens com casos de cumulus rasos.

18. 2000 LeMone et al., BAMS CASES

19. 1998 Moeng et al. LES model intercomparisons, test day at OK ARM/CART site. Main trouble agreeing with data is initialization...

20. BOREAS NOJP: today is not independent of yesterday

21. ASOS at Orange MA, NWS: cloud base is now widely measured…. Freedman & Fitzjarrald, 2001

22. There is hope to use the BL accumulation method, but .….

23. Composite of days following cold front passage... Freedman and Fitzjarrald

24. Apply a box budget to see approach to equilibrium modulated by clouds..

25. Lyons (2002) “More clouds over cleared areas” (Cutrim et al., 1995), or this?

26. Stommel, 1946 LCL vs h

27. LBA-ECO, Santarém Base de nuvens, ceilometro, km 77 (275 = 2 outubro 2001)

28. Base de nuvens, ceilometro, km 77 NCL (km67, vermelho tracejado), NCL (km77, magenta sólido) Wet season Dry season

30. · ceilometro - NCL · balanço - vórtice+ armazenamento Medianas mensais dos fluxos de CO2, Estimados por duas maneiras:: 1. covariancia + armazenamento a 58m, km67 2. Método do balanço: )

32. Detail along Tapajos (Moore et al. 2001) (from U. Maryland) More or fewer clouds over cleared lands vs. forest? From Elen Cutrim, UWMich

33. The river breeze leads to wind reversals only on days with slack Easterlies, but the cloud effects are clear on all days.

34. M. A. F. Silva Dias et al., 2001

35. M. A. F. Silva Dias et al., 2001

36. M. A. F. Silva Dias et al., 2001 October 1, 2001 (from IAG-USP web site)

37. M. A. F. Silva Dias et al., 2001

39. Km 77: response to land use change CD-03 UAlbany/UFSM January 2002 plowed October 2000 pasture November 2001 burning H LE C night Burn C day Albedos Net radiation Soil moisture 2000 2001

40. R R R

41. What do station observations represent? What goes on at night? - 26 stations Albany NY : There are trees and open spaces & …..

42. At the end of the day, Temporal variability --> spatial variability Acevedo & Fitzjarrald, 2001

43. Acevedo & Fitzjarrald, 2001

46. Estrutura vertical Acevedo & Fitzjarrald, 2003

47. Transmission Factor South N-NE . Acevedo & Fitzjarrald, 2003

48. FT FT

49. Fluxes inferred from elevation and TF FT FT

50. Hc: Hc ≈ 30 m