Chapter 3. Hypothesis for the inter-model spread in tropical precipitation pattern
3.2. Data and methodology
We examine the monthly data of historical simulations from 13 CMIP3, 35 CMIP5 and 48 CMIP6 models (Table 3.1) (Eyring et al., 2016; Taylor et al., 2012). We only use the first ensemble member for each model. Net energy input, NEI is calculated as the sum of downward net TOA radiation and upward net surface energy flux. atmospheric energy transport, AET is calculated by taking the spatial integral of the right-hand side of Eq. (1.1) over the Southern Hemisphere, after subtracting the global- mean. We adopt this indirect method for estimating cross-equatorial atmospheric energy transport, AET0 because the temporal resolution is too coarse to resolve transient eddies.
The observed climate features are characterized by two datasets for precipitation: Global Precipitation Climatology Project (GPCP) (Adler et al., 2003) and Climate Prediction Center (CPC) merged analysis precipitation (CMAP) product (Xie & Arkin, 1997). In contrast to the models, we use a direct method for calculating observed estimate of AET using four-times daily European Center for Medium-Range Weather Forecasts (ECMWF) Interim Reanalysis (ERA-Interim) product (Dee et al., 2011). When calculating AET, winds are first forced to balance the atmospheric mass budget with a barotropic wind correction as in (Trenberth, 1997). The corrected winds are used to calculate the meridional flux of moist static energy, which is then vertically integrated to derive AET. The observed estimate of NEI is obtained as the sum of atmospheric heat storage and AET divergence, following Eq.
(1.1).
Both CMIP and observations are analyzed for the 20-year period from 1980 to 1999 and interpolated to a common 1o× 1o grid. In both cases, equatorial averaged net energy input, NEI0 is calculated as the area-average over 6oS-6oN. While the exact value of NEI0 is sensitive to the meridional boundary of integration, it does not affect the qualitative features of our results.
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Table 3.1. Descriptions of CMIP3, CMIP5 and CMIP6 models used in Chapter 3. Model numbers are sorted in order of increasing magnitude of SYM1-PC.
Model Model
Model name Institution AMIP SWAclr
number type
1 CMIP3 inmcm3 INM, Russia Yes No
2 CMIP5 MPI-ESM-LR MPI-M, Germany Yes Yes
3 CMIP3 mpi_echam5 MPI-M, Germany Yes No
4 CMIP5 MPI-ESM-P MPI-M, Germany No Yes
5 CMIP5 MPI-ESM-MR MPI-M, Germany Yes Yes
6 CMIP3 cnrm_cm3 CNRM and CERFACS, France Yes No
7 CMIP5 CSIRO-Mk3-6-0 CSIRO, Austrailia Yes Yes
8 CMIP6 NESM3 NUIST, china Yes Yes
9 CMIP6 MPI-ESM-1-2-HAM MPI-M, Germany No Yes
10 CMIP6 SAM0-UNICON SNU, Republic of korea Yes Yes
11 CMIP6 NorESM2-LM NCC, Norway Yes Yes
12 CMIP6 AWI-CM-1-1-MR AWI, Germany No Yes
13 CMIP5 bcc-csm1-1-m BCC, CMA, China Yes Yes
14 CMIP6 MPI-ESM1-2-LR MPI-M, Germany No Yes
15 CMIP6 MPI-ESM1-2-HR MPI-M, Germany Yes Yes
16 CMIP5 CMCC-CESM CMCC, Italy No No
17 CMIP5 MIROC5 AORI, NIES, and JAMSTEC, Japan Yes Yes
18 CMIP5 CESM1-WACCM DOE NCAR, USA No Yes
19 CMIP6 INM-CM4-8 INM, Russia Yes Yes
20 CMIP6 NorESM2-MM NCC, Norway No Yes
21 CMIP6 IITM-ESM CCCR, India Yes Yes
22 CMIP6 CMCC-CM2-SR5 CMCC, Italy Yes Yes
23 CMIP5 CESM1-CAM5 DOE NCAR, USA Yes Yes
24 CMIP3 mri_cgcm2_3_2a MRI, Japan Yes Yes
25 CMIP3 ukmo_hadgem1 MOHC, UK No Yes
26 CMIP6 E3SM-1-1-ECA LLNL, USA No Yes
27 CMIP6 E3SM-1-1 LLNL, USA No Yes
28 CMIP5 bcc-csm1-1 BCC, CMA, China Yes Yes
29 CMIP6 BCC-ESM1 BCC, china Yes Yes
30 CMIP6 CanESM5 CCCma, Canada Yes Yes
31 CMIP6 GFDL-ESM4 GFDL, USA No Yes
32 CMIP6 EC-Earth3-Veg EC-Earth consortium Yes Yes
33 CMIP6 UKESM1-0-LL MOHC, UK Yes Yes
34 CMIP5 inmcm4 INM, Russia Yes Yes
35 CMIP6 CMCC-CM2-HR4 CMCC, Italy No Yes
36 CMIP6 EC-Earth3 EC-Earth consortium Yes Yes
37 CMIP6 GISS-E2-1-H NASA/GISS, USA No Yes
38 CMIP6 IPSL-CM6A-LR IPSL, France Yes Yes
39 CMIP5 CMCC-CM CMCC, Italy Yes No
40 CMIP3 cccma_cgcm3_1_t63 CCCma, Canada No Yes
41 CMIP5 MRI-CGCM3 MRI, Japan Yes Yes
42 CMIP6 E3SM-1-0 LLNL, USA Yes Yes
43 CMIP5 CESM1-BGC DOE NCAR, USA No Yes
44 CMIP6 GISS-E2-1-G NASA/GISS, USA Yes Yes
45 CMIP6 INM-CM5-0 INM, Russia Yes Yes
46 CMIP3 fgoals1_0_g LASG, IAP, CAS, and CESS, China No Yes
47 CMIP5 CNRM-CM5-2 CNRM and CERFACS, France No Yes
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48 CMIP3 gfdl_cm2_0 NOAA GFDL, USA No Yes
49 CMIP6 CESM2-WACCM NCAR, USA Yes Yes
50 CMIP6 GISS-E2-1-G-CC NASA/GISS, USA No Yes
51 CMIP5 CCSM4 NCAR, USA Yes Yes
52 CMIP6 CESM2-FV2 NCAR, USA Yes Yes
53 CMIP5 MRI-ESM1 MRI, Japan No Yes
54 CMIP6 CESM2-WACCM-FV2 NCAR, USA Yes Yes
55 CMIP5 CNRM-CM5 CNRM and CERFACS, France Yes Yes
56 CMIP5 IPSL-CM5A-MR IPSL, France Yes Yes
57 CMIP6 HadGEM3-GC31-LL MOHC, UK Yes Yes
58 CMIP6 TaiESM1 RCEC, Taiwan Yes Yes
59 CMIP6 GFDL-CM4 GFDL, USA Yes Yes
60 CMIP5 CESM1-FASTCHEM DOE NCAR, USA No Yes
61 CMIP3 cccma_cgcm3_1 CCCma, Canada No Yes
62 CMIP5 IPSL-CM5A-LR IPSL, France Yes Yes
63 CMIP6 BCC-CSM2-MR BCC, china Yes Yes
64 CMIP5 CanESM2 CCCma, Canada Yes No
65 CMIP6 MIROC6 AORI, NIES, and JAMSTEC, Japan Yes Yes
66 CMIP6 CNRM-CM6-1 CNRM and CERFACS, France Yes Yes
67 CMIP3 ncar_ccsm3_0 NCAR, USA Yes Yes
68 CMIP6 HadGEM3-GC31-MM MOHC, UK Yes Yes
69 CMIP6 CNRM-ESM2-1 CNRM and CERFACS, France Yes Yes
70 CMIP5 HadGEM2-ES MOHC, UK No Yes
71 CMIP6 CESM2 NCAR, USA Yes Yes
72 CMIP6 MIROC-ES2L AORI, NIES, and JAMSTEC, Japan Yes Yes
73 CMIP5 GISS-E2-H NASA/GISS, USA No Yes
74 CMIP6 ACCESS-ESM1-5 CSIRO and BOM, Australia Yes Yes
75 CMIP6 MRI-ESM2-0 MPI-M, Germany Yes Yes
76 CMIP6 KACE-1-0-G NIES, South Korea Yes Yes
77 CMIP3 ukmo_hadcm3 MOHC, UK No Yes
78 CMIP6 ACCESS-CM2 CSIRO and BOM, Australia Yes Yes
79 CMIP5 IPSL-CM5B-LR IPSL, France Yes Yes
80 CMIP5 NorESM1-M NCC, Norway Yes Yes
81 CMIP6 CNRM-CM6-1-HR CNRM and CERFACS, France Yes Yes
82 CMIP6 NorCPM1 NCC, Norway Yes Yes
83 CMIP5 GISS-E2-H-CC NASA/GISS, USA No Yes
84 CMIP5 NorESM1-ME NCC, Norway No Yes
85 CMIP6 FGOALS-f3-L CAS, china Yes Yes
86 CMIP6 CIESM THU, China Yes Yes
87 CMIP5 FGOALS-g2 LAS, IAP, CAS and CESS, China Yes No
88 CMIP5 GISS-E2-R-CC NASA/GISS, USA No Yes
89 CMIP5 GISS-E2-R NASA/GISS, USA Yes Yes
90 CMIP5 MIROC-ESM-CHEM AORI, NIES, and JAMSTEC, Japan No Yes
91 CMIP3 ipsl_cm4 IPSL, France Yes Yes
92 CMIP5 MIROC-ESM AORI, NIES, and JAMSTEC, Japan Yes Yes
93 CMIP5 ACCESS1-3 CSIRO and BOM, Australia Yes Yes
94 CMIP3 miroc3_2_hires AORI, NIES, and JAMSTEC, Japan Yes Yes
95 CMIP5 ACCESS1-0 CSIRO and BOM, Australia Yes Yes
96 CMIP6 FGOALS-g3 CAS, china Yes Yes
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