Climas Extraños usando PLASIM René Garreaud & Alejandra Molina DGF-UCH

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Emily Amber Bishop
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2 Climas Extraños usando PLASIM René Garreaud & Alejandra Molina DGF-UCH

3 Climas Extraños usando PLASIM René Garreaud & Alejandra Molina DGF-UCH Model Description Model Validation Rotation Experiments Topography Experiments

4 RG: Conoces algun modelo climatico simple de usar? SS: Claro che hay algo llamado Puma Model Pero buscar Puma Model en Interner puede ser peligroso

5 Model Validation Full (atmos+ocean+ice) SON mean SST Atmos-only (prescribed ocean/ice) Weak cold tongue, small warm pool, too much ice

6 Model Validation Zonal mean, annual mean Precipitation [mm/day] CMAP Full (Atmos+Ocean+Ice) Atmos only SLP [hpa] Latitude

7 Model Validation DJF Precip JJA Precip Full Atmos only Obs.

8 Model Validation DJF mean SLP Full Atmos only Obs NNR

9 Model Validation DJF mean 200 hpa winds Full Atmos only Obs NNR

10 Model Validation Feature Atmos-Only Full Cold tongue Of course weak Warm pool Of course Small ITCZ Ok, too wide Too strong, too zonal South American Monsoon Yes Yes SH Storm Track Yes Yes Orographic precipitation Yes Yes Subtropical deserts Yes, but too small Yes, but too small Subtropical anticylones Yes, but too wide Ok, too wide SPCZ Yes No SACZ Ok, but too short Yes

11 Model Validation Atmos. only model Circulation Topography Rotation Precipitation Farias model SST Atmos-Ocean model Atmos-Ocean model includes more processes but it has a less realistic representation of the basic state

12 Rotation Experiments Annual mean precipitation [mm/month] Full (a-o-i) Control Full, Inverse rotation Full, slow rotation (10 days) Control (lines) and slow-rot (shaded) annual mean precip [mm/month]

13 DJF surface winds Control Rotation Experiments Slow Rot Inv. Rot

14 Rotation Experiments Inverse-Rot minus Control SST/SAT SON MAM C

15 Rotation Experiments DJF mean Precip JJA mean Precip mm/month Control InvRot 60 InvRot Minus Control

16 Rotation Experiments DJF mean Precipitation (a) Control (b) Inverse Rotation (c) InvRot minus Control

17 Topography Experiments

18 Topography Experiments

19 Topography Experiments Motivated by the previous wisdoms in the paleo-climate and geological communities, we set up a numerical experiment using PLASIM: Experiment Topography Ocean/Ice model Control 100% Yes Atmos Only 100% No 0.1Topo-f 10% everywhere Yes 0.3Topo-f 30% everywhere Yes 0.5Topo-f 50% everywhere Yes 0.7Topo-f 70% everywhere Yes 0.9Topo-f 90% everywhere Yes 0.3Topo-A 30% everywhere No 0.3Andes-f 30% South America Yes 0.3Andes-A 30% South America No

20 Topography Experiments 0.3*Topo minus Control (DJF) 900 hpa winds and Precip % Precip ( P/Pc) + mm/day %

22 Topography Experiments DJF Precipitation R>100 mm/month R< 10 mm/month Control 0.3*Andes Control 0.3*Andes

23 f*topo minus Control (DJF) f = 0.1 f = 0.3 Topography Experiments f = 0.5 f = 0.9 f = 0.7 f* = 0.3 mm/day

24 Topography Experiments Austral Andes (45-50 S W) Precipitation change [Pe/Pc*100 %] SESA (15-25 S W) Andes only Interannual variability ( ) Topographic reduction factor

Control -37 C -27 C Deep convections warms the tropical / subtropical tropospher, producing a warm-core upper-level anticyclone -47 C Topography Experiments R>100 mm/month Control 0.

25 Control -37 C -27 C Deep convections warms the tropical / subtropical tropospher, producing a warm-core upper-level anticyclone -47 C Topography Experiments R>100 mm/month Control 0.3Andes - Control Subsidence Cold Adection T (cooling) Upward P (less precip) Rodwell-Hoskins Mechanism Strong cold advection occurs where the westerly flow encounters the upper-level warm region. Thermal balance requires enhanced susbidence, strengthening the SEP subtropical anticyclone Smaller Andes reduce rainfall over the interior of the continent and thus reduce the warming of the upper-troposphere less thermal gradient less cold advection. less subsidence?

26 Topography Experiments DJF 400 hpa South American Region (60 S-20 N, E) Subsidence SEP anticyclone Vertical velocity [cm/s] SACZ Central SA Upsidence Temperature advection [10*K/day]

27 Topography Experiments DJF, 400 hpa w 0.3 cm/s Control 0.3Andes Vertical velocity [cm/s] 0.3Andes Control Temperature advection [10*K/day] 0.3Andes Control

28 Rotation Experiments Inverse-Rot minus Control SST/SAT SON MAM C

29 Rotation Experiments

30 Topography Experiments 0.3*Topo minus Control (DJF) 900 hpa winds and Precip % Precip ( P/Pc) + mm/day %

31 Topography Experiments DJF Precipitation R>100 mm/month R< 10 mm/month Control 0.3*Andes Control 0.3*Andes

Large scale control on the climate of Patagonia

Large scale control on the climate of Patagonia René Garreaud 1, Paulina Lopez, 2 Marie Minvielle 1 and Maisa Rojas 1 1: Department of Geophysics, Universidad de Chile 2: Centro de Estudios Cientificos