WGCM Meeting, Dubrovnik, 18-20 October 2015
Solar Forcing for CMIP6
Katja Matthes1,2 and Bernd Funke3
1GEOMAR Helmholtz Centre for Ocean Research Kiel, Germany 2Christian-Albrechts Universität zu Kiel, Kiel, Germany
3Instituto de Astrofísica de Andalucía, CSIC, Granada, Spain
Overview
• New reference SSI/TSI (and particle) forcing • Future solar (SSI and particle) forcing
• Final comments (solar forcing in PI control, solar ozone forcing)
2
Relative Contribution to TSI
New SSI Reference!
-100
-50
0
50
100
150
200
6 S
SI
/ 6
TS
I [in
per
cent
]
200-400 400-700 700-1000 1000-2430
NR
LSS
IS
ATIR
EC
OS
IO
AR
SC
IAM
AC
HY
SO
RC
E
SU
SIM
WR
-2002
SO
RC
E reanalysis
NRLSSISATIRECOSIOARSCIAMACHYSORCE
WR-2002SUSIM
SORCE reanalysis
Ermolli, Matthes, Dudok de Witt et al., ACP (2013)
NRLSSI1 = standard so far (CMIP5, CCMVal, CCMI)
merged SATIRE+ NRLSSI2 = new reference data set
0.1
1
10
100
Pre
ssu
re (
hP
a)
GEOSCCM NRLSSIGEOSCCM SORCEIC2D NRLSSIIC2D SORCEEMAC!FUB NRLSSIEMAC!FUB SORCEWACCM NRLSSIWACCM SORCEWACCM* NRLSSIECHAM6 NRLSSIHadGEM3 SORCEMMM NRLSSIMMM SORCE
!0.6 !0.4 !0.2 0 0.2 0.4 0.6
20
25
30
35
40
45
50
55
60
Heig
ht
(km
)
Shortwave Heating Rate
Stronger SSI forcing leads to stronger SW HR and temperature response!
SSI Impact on Atmospheric Response
Temperature
Ermolli, Matthes, Dudok de Witt et al., ACP (2013)
New TSI Reference Value
5
New TSI value 1360.8 ± 0.5 W m−2
Old TSI value 1365.4 ± 1.3 W m−2 (Kopp and Lean, 2011; Ermolli et al., 2013)
Courtesy T. Dudok de Wit (2015)
New CMIP6 Reference Dataset
6
1850 1900 1950 2000 2050 2100
CMIP6 solar forcing: one netcdf file SSI, TSI, F10.7cm, kp, ap, GCR, protons daily resolution, 1850-2300, 2 scenarios (ref, extreme min)
particle forcing: auroral electrons, solar protons, galactic cosmic rays
radiative forcing: TSI, SSI, F10.7cm
7
Two Future Scenarios
Reference future scenario
Extreme Maunder Minimum future scenario
Courtesy T. Dudok de Wit (2015)
TSI: NRLSSI (ext=red, ref=black), SATIRE (ext=blue)
1 Jan1850
1 Jan1978
1 Jan2106
1 Jan2234
1359.5
1360.0
1360.5
1361.0
1361.5
1362.0
W/m
2
8
Two Future Scenarios
Reference future scenario
Extreme Maunder Minimum future scenario
1850 1980 2100 2300
9
CMIP6 Solar Forcing
Current status CMIP6 solar forcing dataset: Option1: Reconstruction based on empirical scaling (sunspot number – solar modulation potential) (ready, grey curve above) Option2: Merged SSI/TSI dataset from NRLSSI2 and SATIRE-S models
(SATIRE-S ready, NRLSSI2 almost)
CMIP5
CMIP6
SATIRE-TS
NRLSSI2
Summary
• New reference SSI/TSI (+particle forcing) dataset ready by January 1st 2016 (1nm, daily resolution, 1850-2300, one netcdf file)
• Will be validated in lbl and climate model simulations
(part of CMIP6 solar forcing special issue)
10
Final Remarks
• Solar forcing for PI control experiment:
² One constant value for TSI and SSI spectrum representative for 1850 solar cycle mean conditions
² Optional: second PI control with solar cycle
variability but no long-term trend included
• Solar ozone forcing timeseries is coordinated with CCMI ozone dataset (M. Hegglin)
11