on the closure of the surface energy balance in highly complex terrain
DESCRIPTION
On the Closure of the Surface Energy Balance in Highly Complex Terrain. Mathias W. Rotach, Pierluigi Calanca, Andreas Weigel, Marco Andretta Swiss Federal Institute of Technology Institute for Atmospheric and Climate Science. Layout. Surface energy balance Data: MAP -Riviera project - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/1.jpg)
On the Closure of the Surface Energy Balance in
Highly Complex Terrain
Mathias W. Rotach, Pierluigi Calanca, Andreas Weigel, Marco Andretta
Swiss Federal Institute of TechnologyInstitute for Atmospheric and Climate Science
![Page 2: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/2.jpg)
Layout
• Surface energy balance• Data: MAP -Riviera project• Energy balance for a layer• Implications for modeling
![Page 3: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/3.jpg)
MAP-RivieraValley Floor Slope site
Average 15 fair-weather days
![Page 4: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/4.jpg)
Surface Energy balance
NR
G
Ho LvEo
NR-G=Ho+LvEo
![Page 5: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/5.jpg)
Surface Energy balance
• horizontally homogeneous surfaces --> constant turbulent fluxes --> no advection --> closure! [even @ z≠0...]
NR-G=Ho+LvEo
![Page 6: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/6.jpg)
Surface Energy balance
• horizontally homogeneous surfaces --> constant turbulent fluxes --> no advection --> closure! [even @ z≠0...] --> non-closure: measurement error turbulence time scales
NR-G=Ho+LvEo
![Page 7: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/7.jpg)
Surface Energy balance
• horizontally homogeneous surfaces --> constant turbulent fluxes --> no advection --> closure! [even @ z≠0...] --> non-closure: measurement error turbulence time scales
complex terrain...
NR-G=Ho+LvEo
![Page 8: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/8.jpg)
Bellinzona
Biasca Riviera
MAP Riviera project
Lago Maggiore
![Page 9: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/9.jpg)
MAP Riviera project
![Page 10: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/10.jpg)
MAP Riviera Project
![Page 11: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/11.jpg)
MAP-Riviera: Bosco di Sotto
turbulence @ 4 / 16 / 28 m
Local surface: corn, grass
Full radiation comp, precip, profiles,sfc. hydrology
Local slope app. 0.5°
![Page 12: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/12.jpg)
NR
G
Ho LvEozr
H(zr) LvE(zr)
Near-Surface Energy Balance
![Page 13: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/13.jpg)
Near-Surface Energy Balance
NR
G
Ho LvEo
NR-G=Storage+horiz.Adv +vert.Adv
Hr LvEr
z=zr
u Jx
o
zr
dz
w r (J r 1zr
J dzo
zr
)
J cp Lvq
S
G
![Page 14: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/14.jpg)
Corrections
• Sensible Heat flux: --> frequency response (Moore 1986)
--> humidity cross-correlation (Schotanus et al. 1983)• Latent heat flux: --> frequency response (Moore 1986) --> Oxygen (Dijk et al. 2003)
--> WPL-correction (Webb et al. 1980)
![Page 15: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/15.jpg)
Horizontal Advection
Comprovasco
Magadino
u Jx
o
zr
dz
, q
, q
u
J cp Lvq
Riviera
![Page 16: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/16.jpg)
Vertical Advection
, q
, q
zr
w
w r (J r 1zr
J dzo
zr
)
J cp Lvq
Mean vertical wind: from planar fit
![Page 17: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/17.jpg)
Results...
![Page 18: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/18.jpg)
Energy balance terms
NR
H+LE+G
New sum
LE
GH
Average 7 clear sky days
![Page 19: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/19.jpg)
Contributing terms
Sum new terms
Storage air / horiz. advection
Storage soilSum corrections
Vertical advection
Average 7 clear sky days
![Page 20: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/20.jpg)
Vertical advection
ProprtionalDifference in , q....
![Page 21: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/21.jpg)
Vertical advection
Proprtionalmean vertical wind
![Page 22: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/22.jpg)
Energy balance terms
NR
H+LE+G
New sum
LE
GH
Average 7 clear sky days
![Page 23: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/23.jpg)
Conclusions
• Sfc. energy balance in really complex terrain: good to detect processes
• Corrections to turbulent fluxes important• Soil storage term important• Vertical advection!
--> largest--> most uncertain!
![Page 24: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/24.jpg)
Outlook
• If indeed vertical advection is substantial....--> too large a fraction of NR --> H, LE--> cold / dry bias
![Page 25: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/25.jpg)
RAMS simulations - August 25 1999
9.15 UTC 12.08 UTC
observations
model
De Wekker et al. 2003
![Page 26: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/26.jpg)
QuickTime™ and aGraphics decompressorare needed to see this picture. BBBBBBBBBBBBBBBBBBBBBJJJJJJJJJJJJJJJJJJJJJHHHHHHHHHHHHHHHHHHHHH294298302306294298302306Mo
del
edObservedBRAMSJMM5HETABBBBBBBBBBBBJJJJJJJJJJJJHHHHHHHHHHHH294298302306294298302306M
od
eled
ObservedBBBBBBBBBBBJJJJJJJJJJJHHHHHHHHHHH294298302306294298302306Mo
del
ed
ObservedBBBBBBBBBBBBBBBBBBBJJJJJJJJJJJJJJJJJJJHHHHHHHHHHHHHHHHHHH294298302306294298302306Mo
del
edObservedGGGGGGGGGGGGGGGGGGGGGGGGGEEEEEEEEEEEEEEEEEEEEEEEEECCCCCCCCCCCCCCCCCCCCCCCCC
Wheeler FarmNCARAirport All sitesDay: SolidNight: Open
Salt Lake Valley - VTMX
Different models:RAMSMM5ETA
Zhong and Fast 2002
IOP‘s 6,7,10
![Page 27: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/27.jpg)
Outlook
• If indeed vertical advection is substantial....--> too large a fraction of NR --> H, LE--> cold / dry bias
• How to parameterize in numerical models?
![Page 28: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/28.jpg)
Comparisons of observed and simulated sensible heat fluxes
![Page 29: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/29.jpg)
Hydrological modeling – valley floor
Soi
l mo i
stur
e (.
5 m)
ET
und
LE
[m
m/h
]
Pre
cipi
tatio
n [m
m/h
]E
T u
nd L
E [
W/m
2]
Sept 1 1999 Sept 21 1999
![Page 30: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/30.jpg)
ET
und
LE
[W/m
2 ]
time
Observation(Bowen Ratio)
Model (Penman-Monteith)
Eddy Correlation
Hydrological modeling – valley floor
![Page 31: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/31.jpg)
Closed energy balance• Bowen ratio method:
--> if
and
Ho KHz
, LEo Kqq z
KH Kq
Ho
LEoz
q z
Ho NR G11
, LEo NR G1
![Page 32: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/32.jpg)
Planar fitPlot w as a function of (u,v)....
![Page 33: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/33.jpg)
Planar fit on a slope
![Page 34: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/34.jpg)
Common plane vs. local planes
Planar fit vs. Double rotation
(<u
‘w‘>
PF
C -
<u
‘w‘>
DR)/
<u
‘w‘>
DR
(<u
‘w‘>
PF
C -
<u
‘w‘>
PF)/
<u
‘w‘>
PF
C
Andretta et al. (2002)
![Page 35: On the Closure of the Surface Energy Balance in Highly Complex Terrain](https://reader035.vdocuments.mx/reader035/viewer/2022062723/56813b48550346895da42fb3/html5/thumbnails/35.jpg)
Finnigan et al. 2003
Energy Balance closure
Data from a ‚flux site‘ in Manaus, Brazil
R 100(H LvE [NR G])