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Land-surface model (cover art from Daniel Hillel, Environmental Soil Physics ) COMPONENTS OF PBL LAND SURFACE COUPLING ATMOSPHERIC LES NOAH LAND SURFACE MODEL SURFACE ENERGY BALANCE LES SURFACE FLUXES ARE NOT PRESCRIBED BUT RESULT FROM THE COUPLING 4-3

TM image of El Reno Track, Oklahoma Southern Great Plains Experiment 1997 Soil Moisture Variability Irrigated farm (wet) Undeveloped land (dry) 4-4

wet soil dry soil x (km) y (km) λ = 15 km 4-5

λ / z i ≈ 9 LES OF PBL WITH SURFACE HETEROGENEITY 4-6

λ / z i ≈ 4 INSTANTANEOUS FIELDS 4-7

VELOCITY VARIANCES WITH HETEROGENEITY Total u-variance depends on heterogeneity Total w-variance nearly constant 4-8

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Phase Averaged Velocity Fields λ / z i ≈ 4 λ / z i ≈ 18 λ / z i ≈ 1 u w wetdry x/λ z/z i Patch boundary 4-10

“VIRTUAL” MEASUREMENTS Tall towers for single- point flux measurements “Boundary-layer circulations” 4-11

IMPACT OF HETEROGENEITY ON FLUX MEASUREMENTS AT FIXED X 4-12

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u w p x z Vertically staggered scheme Co-located scheme 4-15

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Grid for isolated hill Grid for water waves 4-17

TIME EVOLUTION OF TURBULENT FLOW OVER A HILL 4-18

Averaged in y and t 4-19

Turbulence 4-20

OCEAN MIXED LAYERS HOW DO THEY DIFFER FROM THEIR ATMOSPHERIC COUNTERPARTS? SURFACE WAVES, DO THEY ALTER THE TURBULENT PBL DYNAMICS? LIMITED OBSERVATIONAL DATABASES COMPARED TO THE ATMOSPHERE 4-21

BREAKING WAVES IN THE GULF OF TEHUANTEPEC COURTESY KEN MEVILLE SCRIPPS INSTITUTE OF OCEANOGRAPHY 4-22

LANGMUIR CIRCULATIONS GREAT SALT LAKE COURTESY S. MONISMITH 4-23

+ wave field (fast) currents (slow) 4-24

(.. ) - Stokes terms (.. ) - Breaker terms Momentum SGS e Density Most important term generated by the waves 4-25

z 4-26

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PARTICLE PATHS OVERLAYING VORTICITY CONTOURS NO BREAKING U 10 = 5m/s 4-29

HOW DOES LATERAL CONVERGENCE HAPPEN? Stokes drift from waves Vortex forces u st x 

COHERENT STRUCTURES IN LES WITH WAVE EFFECTS IDENTIFIED USING STOCHASTIC ESTIMATION (Adrian, 1989) Top view Side view x y x yz 4-31

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