Applications of Climate Model in LAPAN

Transcription

1 Applications of Climate Model in LAPAN Didi Satiadi National Institute of Aeronautics and Space (LAPAN) Workshop on MCCOE Radar Meteorology/Climatology in Indonesia Jakarta, 28 th February 2013

2 Introduction Atmospheric model is a numerical representation of governing equations describing the behaviour of the atmosphere. Atmospheric model can be used as a simulation tool (to study the behaviour of the atmosphere), or as a prediction tool (to find out atmospheric condition in the future). This presentation will describe applications of a climate model (esp. CSIRO GCM/LAM) at the Centre for Atmospheric Science and Technology LAPAN as a tool in atmospheric research. Research on the dynamics of ITCZ using the model and its relationship to monsoon and monsoon onset (esp. Indo-Australian) will be elaborated. The use the Equatorial Atmosphere Radar (EAR) in the development of Convective Scheme will also be discussed. 2

3 A computer program containing a collection of mathematical equations describing the dynamics and physical processes in the real atmosphere. Dynamical Model of the Atmosphere How is the condition of the atmosphere in the future? Operational Weather & Climate Prediction Research & Education How does the atmosphere work? Development Sectors Agriculture, Forestry, Fishery, Transportation, Trade, Industry, Energy, Health, Tourism, Environment, Defence & Security, Education 3

4 Equations for Dynamics and Physics of the Atmosphere Grid of space and Time Are solved within Written in through Computer Program Iteration in Space and Time 4

5 Physical Processes 5

6 Parameterization of Sub-Grid Processes Parameterization scheme is a procedure to calculate the collective effect of sub-grid processes on the model s prognostic variable and vice versa. Climate models with grid size larger than the sub-grid processes need to parameterize the effect of subgrid to the model s prognostic variable at each grid box. 6

7 GCM/DARLAM Modeling System General Circulation Model Nest Generator Limited Area Model Vegetation Generator GCM History Files 500 km GCM2LAM Nesting Files Topofile LAM vegetation rsmin soil roughness albedo Vegie Topgen Dynamic Downscaling 50 km Topography Generator 7

8 Data Input/Output Topography Albedo O 3 /CO 2 Vegetation Surface Roughness SST Ocean Current Ice Cover Soil Type Restart File GCM/ DARLAM Temperature Wind Mixing Ratio Pressure Precipitation Evaporation Heat Flux Radiation Cloud Runoff Latent Heating 8

9 Model Flowchart START Read namelist input Open input/output files Call initial conditions Perform physical adjustment Start of main time loop Perform dynamics step End of main time loop Print various output END Write output 9

10 PC-Based GCM/LAM CSIRO GCM/LAM on SGI Irix Compaq Visual Fortran 6.5 Microsoft Visual C NetCDF Win32e GrADS InstallShields Express Armadillo LAPAN GCM/LAM on PC Windows/ Linux System Requirement: PC Intel (32/64 bit) Pentium IV 1.5 GHz RAM 512MB Hard Disk 1GB OS Windows XP/Vista/7 10

11 Features FITUR CSIRO-GCM/LAM LAPAN-GCM/LAM 1.0 LAPAN-GCM/LAM 1.0 PC-LINUX PC-WINDOWS Compiler F77, CC PGF77, PGCC Visual Fortran, Visual C++ Computer Super-Computer Silicon Personal Computer (PC) Personal Computer (PC) Graphics (SGI) 64-bit AMD-Athlon x86 64-bit Intel x86 32-bit Processor Processor Processor Architecture Stand Alone Stand Alone/Cluster(20) Stand Alone OS Irix 6.5 Linux (SuSe) Windows (XP/Vista) Installation Manual Manual Installshield Wizard Interface Console Console Graphical User Interface Format I/O NeCDF NetCDF NetCDF Display GrADS GrADS GrADS for Windows SST Climatology Climatology Climatology or prediction from NOAA CO2 Determied by program Determined by program Determined by user Convection Static Trigger Static Trigger Static or Dynamic based on DCAPE>0 and DCINH>0 Output Standard Standard Additional convective variables (LCL, LFC, LNB, CAPE, CINH) 11

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13 Simulation Configuration PARAMETER GLOBAL INDONESIA JAWA Model CSIRO-9 GCM (PC) DARLAM (PC) DARLAM (PC) Domain Global Indonesia (60 E- 180 E, 30 S-25 N) Java (100 E-120 E, 10 S-5 S) Grid Size 56x64x9 130x60x9 100x30x9 Resolution 3.2 x km 20 km Time Step 30 minutes 900 seconds 300 seconds Forcing Initial Condition SST prediction NOAA Restart from previous month Nesting from Global Restart from previous month Nesting from Indonesia Restart from previous month Convection Scheme Arakawa Arakawa Arakawa Simulation Time Jan-Dec 2010 Jan-Dec 2010 Jan-Dec

14 Indonesia res. 100 km Global res. 300 km x 500 km Java Island res. 20 km 14

15 Surface Temperature 2010 Horizontal Wind 2010 Cloud Cover 2010 Rainfall

16 Monthly Global Rainfall 2010 TRMM (Top) vs GCM (Bottom)

17 Zonal and Meridional Mean Global Rainfall 2010 (January to September) Model (GCM) vs Observation (TRMM) GCM Double Peak TRMM Afrika Indonesia A. Latin ZONAL MERIDIONAL 17

18 Simulation Results using DARLAM for Indonesia Region January to December 2010 Surface Temperature Surface Pressure Rainfall Horizontal Wind 18

19 Simulation Results using DARLAM for Java Island Region January to December 2010 Surface Temperature Wind Rainfall Meridional Wind 19

20 Rainfall 2010 (January to September) Model vs Observation JAVA INDONESIA GLOBAL TRMM MODEL 20

21 Temperature & Mixing Ratio Profile (Kototabang 11/2005) Model (DARLAM) vs Observation (Radiosonde) OBSERVATION MODEL TEMPERATURE PROFILE MIXING RATIO PROFILE 21

22 Study of Convective Triggering Based on Observation at Kototabang Station

23 Effect of Convective Triggering Xie et. al. (2004) produced better simulation results using a modified convective triggering based on large scale contribution to the rate of change of CAPE. Ref: Journal of Geophysical Research, Vol. 109, D14102, 2004

24 Observation of Mean Diurnal Cycle EAR WWND AVE EAR BLR WWND AVE BLR SODAR SDR WWND AVE ORG ORG RAIN AVE RDS-CAPE 04/2004 & 11/2005 AVE CAPE

25 Observation of Mean Diurnal Cycle CAPE LCL INSTABILITY CLOUD BASE INHIBITION CINH FREE CONVECTION LFC CAP STRENGTH CAP CLOUD TOP LNB TOTAL ENERGY CAPE+CINH DIFFERENCE+ LNB-LFC CLOUD DEPTH LNB-LCL DIFFERENCE- LFC-LCL

26 Modification of Convective Triggering START +DCAPE NO Large Scale Criterion YES Handshaking NO CINH=0 Local Scale Criterion YES ADJUSTMENT STOP

27 TRMM ORIGINAL CONVECTIVE TRIGGERING MODIFIED CONVECTIVE TRIGGERING

28 Study of ITCZ Dynamics Using General Circulation Model and Its Relationship to Monsoon

29 ITCZ, Monsoon & Monsoon Onset According to Chao (2000, 2001, 2004), monsoon is the circulation associated with ITCZ away from the equator. The migration of ITCZ during its annual cycle does not always occur gradually, but sometime jumps towards the poles. The ITCZ jump corresponds to the onset of monsoon.

30 Sumi s Experiment The results of Sumi s experiment using general circulation model with uniform SST and uniform radiative cooling: Single ITCZ along the equator. Double ITCZ stradling the equator. The results must be caused by the earth rotation (Corriolis). Two effects of the earth s rotation on convection: Inertial stability Increased surface fluxes

31 ITCZ Attractor: Corriolis Second Attractor (P) First effect of Coriolis (A) Coriolis against convergence/ divergence, therefore against convection Second effect of Coriolis (B) Coriolis increases surface wind, therefore increases convection First Attractor(EQ) Ref. Chao & Chen (2004)

32 ITCZ Attractor: SST Peak Combined Efect (R) Where R = A - B First Attractor Second Attractor ITCZ Jump ITCZ Jump SST Peak at Equator Ref. Chao & Chen (2004)

33 Bimodality & ITCZ Jump N EQ S N EQ S

34 ITCZ Jump & the Hadley Cell Global Precipitation Climatology Project (GPCP) Ref. Hu et. al. (2007)

35 West African Monsoon Jump Ref. Hagos & Cook, Dynamics of the West African Monsoon Jump, Journal of Climate, 2007

36 EQ

37 EQ

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39 Bimodality of ITCZ based on Cloud Top Temperature (MTSAT )

40 ITCZ Jump based on Cloud Top Temperature (MTSAT ) Jump between rails Jump between rails Rail N Rail S

41 ITCZ Jump Observed by MTSAT vs Indo- Australia Monsoon Indices

42 ITCZ Jump Observed by MTSAT vs Rainfall in Indo-Australia Region (110 E-140 E,15 S-5 S)

43 Zonal-Monthly Mean Rainfall (GCM)

44 Zonal-Monthly Mean Rainfall (TRMM)

45 Latitudional Migration of ITCZ (GCM)

46 Latitudional Migration of ITCZ (TRMM)

47 Latitudional Migration of ITCZ (GCM vs TRMM)

48 Migration of ITCZ-TRMM (180 W-180 E) vs Indo-Australia Monsoon Indices

49 Migration of ITCZ-TRMM (110 E-140 E) vs Indo-Australia Monsoon Indices

50 Summary A portable PC-based global/regional atmospheric model has been developed at LAPAN based on CSIRO GCM/LAM as a tool for research. The model could simulate basic atmospheric processes such as global circulation, monsoon, rainfall etc. Research using EAR has been carried out to improve the performance of the model s convective parameterization (triggering) scheme. Research on the behaviour of ITCZ has been carried out using the model to simulate ITCZ jump as an alternative to predict the onset of monsoon.

51 Thank You