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© F ance Ene gies Ma ines
Cha ac e izing A mosphe ic Bounda y Laye
Tu bulence in he Gul o Lion:
Insigh s om he Meso-NH a mosphe ic model
and a wind lida p o ile
Tanguy LUNEL1,2, Didie RICARD1, Maxime THIEBAUT2
anguy.lunel@um -cn m.
1 Cen e Na ional de Reche ches Mé éo ologiques, Mé éo-F ance - CNRS
2 F ance Ene gies Ma ines
WESC Nan es - 2025-06-25
P ésen a ion F ance Ene gies Ma ine
P ésen a ion F ance Ene gies Ma ines2
●Di icul y in ob aining eliable u bulence in o ma ion om models o he wind indus y:
–Example wi h AROME model: unde es ima ion o TKE in compa ison o an o sho e ixed wind lida p o ile
Con ex
–A 140m:
●TKEAROME = 0.5 m2s-2
– TIAROME = 10 %
●TKELida = 1.5 m2s-2
–TILida = 17 %
m2/s2 m/s .
Mean p o iles on 2023-01
Wind speed Wind di ec ion TKE
→ How o imp o e TKE/TI es ima es om mesoscale models?
P ésen a ion F ance Ene gies Ma ines3
●Me hodology:
–Based on a mosphe ic simula ions - Mesoscale and La ge Eddy Simula ions (LES) - and wind lida p o ile da a
–Real case s udies a :
●Le Planie island, Ma seille, Medi e anean Sea:
Ma e ials and me hods
15 km
Taken F om Thiébau e al. 2024, Cha ac e iza ion o he o sho e wind dynamics
o wind ene gy p oduc ion in he Gul o Lion, Wes e n Medi e anean Sea
P ésen a ion F ance Ene gies Ma ines4
Ma e ials and me hods
●Obse a ional da a:
–Wind lida p o ile
●Sampling a e: 1Hz
●Measu emen heigh s om 60 o
220m a.s.l.
●Meso-NH:
–Resea ch a mosphe ic model wi h p ognos ic TKE,
1.5 o de , 2nd-o de momen s a e diagnosed
–Dynamical downscaling app oach,
coupled o he su ace model SURFEX
1 km 200 m 40 m
AROME analysis
(1.3 km)
P ésen a ion F ance Ene gies Ma ines5
TKE concep s
●Concep s o TKE:
–In obse a ions:
●Tempo al a iance measu ed inside a
small olume
–In models:
●Subg id s Resol ed TKE:
–Resol ed → empo al a iance o
mean wind in he g id poin olume
● > 80% o o al TKE in LES
●~ 50 % in he g ey zone
● Low a he mesoscale
–Subg id → spa ial a iance o wind
inside he olume o he g id poin
● Needed o e ical mixing o
a iables
E olu ion o ins an aneous wind speed a 140 m abo e Le Planie
ws_obs o ws_LES
ws_model_1km
P ésen a ion F ance Ene gies Ma ines6
TKE concep s
●Concep s o TKE:
–In obse a ions:
●Tempo al a iance measu ed inside a
small olume
–In models:
●Subg id s Resol ed TKE:
–Resol ed → empo al a iance o
mean wind in he g id poin olume
● > 80% o o al TKE in LES
●~ 50 % in he g ey zone
● Low a he mesoscale
–Subg id → spa ial a iance o wind
inside he olume o he g id poin
● Needed o e ical mixing o
a iables
E olu ion o ins an aneous wind speed a 140 m abo e Le Planie
ws_obs o ws_LES
ws_model_1km
●Compa ison o model esul s o obse a ions
should conside :
–Subg id and Resol ed TKE
●Well accep ed in he communi y
●≈ Subg id TKE o mesoscale
●≈ Resol ed TKE o LES
P ésen a ion F ance Ene gies Ma ines7
TKE concep s
●Concep s o TKE
–TKE mixing ia K-g adien heo y:
–TKE (e) is used o he Eddy-Di usi i y ela ed mixing:
wi h K = C Lm e1/2
Θ, , u, , w, e
o a g id cell (= esol ed)
P ésen a ion F ance Ene gies Ma ines8
TKE concep s
●Concep s o TKE
–TKE mixing ia K-g adien heo y:
–Lack o mixing in coun e -g adien zone → Eddy-Di usi y / Mass-Flux (EDMF) schemes
–TKE (e) is used o he Eddy-Di usi i y ela ed mixing:
wi h K = C Lm e1/2
–Mass-Flux ela ed mixing does no use di ec ly TKE
Mass-Flux
(MF)
Eddy-Di
(ED)
wu
Θu, u, uu, u,
ee
Eddy-Di
(ED)
Θe, e, ue, e, we,
ee
Θ, , u, , w, e
o a g id cell (= esol ed)
De ainmen
En ainmen
au
Wi h au : ac ion o upd a / wu, we : e ical eloci y in upd a /en i onmen
P ésen a ion F ance Ene gies Ma ines9
TKE concep s
●Concep s o TKE
–TKE mixing ia K-g adien heo y:
–Lack o mixing in coun e -g adien zone → Eddy-Di usi y / Mass-Flux (EDMF) schemes
–TKE (e) is used o he Eddy-Di usi i y ela ed mixing:
wi h K = C Lm e1/2
–Mass-Flux ela ed mixing does no use di ec ly TKE
Mass-Flux
(MF)
Eddy-Di
(ED)
wu
Θu, u, uu, u,
ee
Eddy-Di
(ED)
Θe, e, ue, e, we,
ee
Θ, , u, , w, e
o a g id cell (= esol ed)
De ainmen
En ainmen
au
●TKE (e) is in his case a a iable used o mixing
●Bu TKE does no accoun o he e ical eloci y
a iance coming om he p esence o no o upd a
●Ex: MYNN scheme in WRF / EDKF scheme in Meso-NH and AROME
Wi h au : ac ion o upd a / wu, we : e ical eloci y in upd a /en i onmen
P ésen a ion F ance Ene gies Ma ines16
P elimina y esul s
●Ve ical p o iles abo e Le Planie Island
–Imp o emen wi h LES
–Bu insu icien TKE in he LES?
Al i ude a.s.l. [m]
m/s m2/s2
Mean e ical p o iles abo e Le Planie on 2023-01-22 a.m.
P ésen a ion F ance Ene gies Ma ines17
P elimina y esul s
●Ve ical p o iles abo e Le Planie Island
–Imp o emen wi h LES
–Bu insu icien TKE in he LES?
~100m
–O ques ionable lida da a?
●2 main unce ain ies sou ces:
–In e -beam and in a-beam e ec s
●2 TKE e ie al me hods:
–s anda d me hod (in e + in a)
– a iance me hod (in a)
Al i ude a.s.l. [m]
m/s m2/s2
Mean e ical p o iles abo e Le Planie on 2023-01-22 a.m.
P ésen a ion F ance Ene gies Ma ines18
P elimina y esul s
●C i ical iew on he TKE da a om wind lida p o ile
–Va iance me hod is impac ed only by in a-beam e ec → sys ema ic unde es ima ion o wind a iance
–Bu a iance me hod should be used only i wind di ec ion is aligned wi h a pai o opposi e beams
→ In he end, LES and lida da a
p o ide consis en esul s
Al i ude a.s.l. [m]
m/s m2/s2
Mean e ical p o iles abo e Le Planie on 2023-01-22 a.m.
P ésen a ion F ance Ene gies Ma ines19
P elimina y esul s
●Ve ical p o iles abo e Le Planie Island :
–Wi h conside a ion o Mass-Flux ela ed wind a iance: TKE_EQ
→ Mesoscale model able o gi e
easonably good TKE alues in he
middle o ABL
→ Mo e di icul ies o he su ace
bounda y laye
Al i ude a.s.l. [m]
m/s m2/s2
Mean e ical p o iles abo e Le Planie on 2023-01-22 a.m.
P ésen a ion F ance Ene gies Ma ines20
P elimina y esul s
●C oss-sec ions o TKE
–On he mo ning (uns able) – 07:00 UTC
●TKE a he well cap u ed o sho e,
i.e. a Le Planie island
●S ill majo di e ences nea he coas
– o in es iga e
1 km
40 m
TKE and Ri a 09:00 UTC
To al TKE [m2 s-2]
To al TKE [m2 s-2]
P ésen a ion F ance Ene gies Ma ines21
Discussion / conclusion
●P elimina y esul :
–A p ope accoun ing o EDMF ela ed wind a iance allows o be e ma ch
be ween mesoscale models and obse a ions o he TKE
–Va iance me hod o lida measu emen s is use ul o in e p e a ion o obse ed TKE
●Nex s eps:
–O he case s udies
–Wo k on he TKE dissipa ion a e
P ésen a ion F ance Ene gies Ma ines22
© F ance Ene gies Ma ines
Thank you o you a en ion
P ésen a ion F ance Ene gies Ma ines24
P elimina y esul s
●Componen s o mean p o iles
P ésen a ion F ance Ene gies Ma ines25
P elimina y esul s
●Va iance s S anda d me hod o TKE e ie al om Lida
Taken F om Thiébau e al. 2024, Cha ac e iza ion o he o sho e wind dynamics
o wind ene gy p oduc ion in he Gul o Lion, Wes e n Medi e anean Sea
P ésen a ion F ance Ene gies Ma ines26
P elimina y esul s
●C i ical iew on he TKE da a om wind p o iling lida
–Reliabili y seems o depend on heigh and dimensions
Ve ical p o iles abo e Le
Planie on 2023-01-05
a 10:00 UTC
