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Advantages of tropical boundary layer studies.

" Local tropical boundary layer circulations seen from surface station and Lagrangian balloon observations. ” David Fitzjarrald, Atmospheric Sciences Research Center January 14, 2014. Advantages of tropical boundary layer studies. • Regular sequence of weather, near-constant background flows

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Advantages of tropical boundary layer studies.

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  1. "Local tropical boundary layer circulations seen from surface station and Lagrangianballoon observations.” David Fitzjarrald, Atmospheric Sciences Research Center January 14, 2014

  2. Advantages of tropical boundary layer studies. • Regular sequence of weather, near-constant background flows • Geographical influences (topographic flows, breeze circulations) clearly expressed • Composites of climate data more completely resembles individual cases • Observational case studies more • Model studies are nearly always case studies.

  3. Two topics, two tropical projects Barbados 1968 Garstang and LeSeur, FSU; Geoffrey Rudder, UWI Trade winds; water surrounds the land; zi ≈ 600 m , H ≈ 20 W/m2 ABLE-2, LBA (eastern Amazon Basin) 1985-87; 1998-2006 Trade winds; land surrounds the water;zi≈ 1200 m, H ≈ 150 W/m2 Green Ocean Amazon a. Lagrangian balloons to detect local circulations, cloud effects. b. Surface station data surface convergence patterns, geographic and breeze effects on rainfall

  4. Boundary layer in the Caribbean trade-wind zone Joanne Starr Malkus, 1958, WHOI Report Vol. 13, No. 2

  5. Tethered balloon, 1968 Aircraft and surface launched “constant-level” balloons

  6. Barbados Balloon tracked into Cu updraft Great rejoicing! Checked “jet” theory of entrainment

  7. Surface layer divergence Night Day Monthly average 3 selected days Aspliden et al. (1977)

  8. 1971

  9. Amazon convective boundary layer, thick CBL, high sensible heat flux zi H LE Rn Martin et al, 1990

  10. Does it matter that many long-term climate stations are all along the rivers?

  11. Confluence of the Amazon and Tapajós rivers. 15-20 km wide Average GOES low cloudiness May 2001 Known bias in clouds from the river breeze effect. What kind of rainfall bias is there? Molion and Dallarosa (≈1980’s) River breeze. Detected breeze at Manaus back in 1985, 1987 (ABLE-2). Oliveira & Fitzjarrald (1990 ab); (LBA, CIRSAN, Santarém) STM breeze Silva Dias et al. (2001) Lu et al. (2005)

  12. Forest flux towers

  13. 0-12Z 12-0Z Santarém rain radar composites 2009-2011 Cohen et al, (2014)

  14. Modeled moisture convergence NB: dual breeze signature… Are the 2 flux towers in different rainfall regimes? BRAMS simulation Julia Cohen, UFPa

  15. Sample modeled trajectories (HYSPLIT) D’Amelia et al. (2009) Trajectories: usually modeled, rarely observed in the tropics!

  16. Quasi_Lagrangian balloons, 2011-present

  17. Prof. Paul Voss, Smith College

  18. CHUVA-Belém June 2011 Belém São Miguel Tomé-Açu Mesoscale triangle..

  19. Júlia Cohen Luiz Machado Paul Voss Velho gringo

  20. Aproveitandoradiosondagem do Projeto CHUVA emTomé-Açu Q q zi CLC tradicional… 23/6/2011 0Z

  21. 25/6/2011 12Z Sondacomparado com CMET #1 (verde)

  22. Detour?

  23. The life of CMET #1

  24. Modeled trajectories Thought launched 12 h apart, each balloon landed in the Tocantins River, 7 km apart,

  25. CMET #1 & #2 recovered! “The most valuable fish I ever caught.” Address, phone, UFPa Paul Voss receiving balloon #2 April 2012

  26. Our dream: Launch a fleet of CMET into the Amazon Basin low-level inflow. (On to Bolivia!) Our reality: Two CMET balloons brought into Brazil (CHUVA-Belém project) for a pilot study. Watch them crash into the Tocantins River (On to Oblivion!) but not quite…

  27. March (5 CMET) and October (13 CMET) 2014 CMET balloons to be launched during GO-Amazon Based Manaus, Amazonas

  28. Downwind of Manaus Slide from Scot Martin, GO-Amazon Project • 111 by 60.8 km represented by this box. • Wind speeds at 1 km altitude are typically 10 to 30 kph. • T2→T3 transit time of 2 to 6 hr.

  29. River breeze will likely interrupt their ‘dream’ of predictable trajectories… GO-Amazon sampling strategy, February/March 2014 (figure from Kuhn et al. 2010)

  30. Seeking wisdom from another mentor: Wyngaard, Preface: 8:3: “…modeling and observational work have cruelly different time scales. Now less rooted in personal experience, wariness of modeling seems to be diminishing.” Wyngaard, Preface: 12:3: “…models can be easily misused and misinterpreted.”

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