On-going and planned projects with
ECHAM
ETH
Martin Wild, Doris Folini, Adeline Bichet,
Maria Hakuba, Christoph Schär
IACETH
Simulations with ECHAM5-HAM
Model
ECHAM5-HAM (updated from Stier et al. 2005), Version Oct. 2008
Detailed aerosol treatment (prognostic equations for number and mass)
Experiments (carried out by Doris Folini at CSCS)
ETH
- Transient simulations (atmosphere only, prescribed SSTs)
- Historic emission inventories: NIES
- Resolutions from T42L19 to T106L31
List of Ensembles Simulations
#members:
1870 – 2000, default “all forcings“ simulations, T42 (T63)
13 (9)
Sensitivity experiments:
1950 – 2000, SO2 emissions at level of 1950, T42
3
1950 – 2000, BC / OC emissions at level of 1950, T42
3
1870– 2000, all anth. aerosol emissions constant, T42 (T63)
6 (3)
1870 – 2000, all anth. aerosol emissions constant, no volcanoes:
3
1870 – 2000, fixed climatological SSTs, T42 (T63)
13 (1)
Research focus
Significant decadal changes in the observed
components of the Earth energy and water balance
•
•
•
What are the origins of these changes?
What is their impact on climate system components
and climate change?
How will these components evolve in the future?
Atmospheric transmission 1950-2002
ETH
“dimming”
Observed precipitation NH mean land
“brightening”
“dimming”
Wild et al. 2005: Science 308
“brightening”
Research focus: origins of changes
• What are the origins of these changes?
=> sensitivity studies, impact of various types of aerosol on decadal
changes in surface solar radiation
Surface solar radiation:
constant versus
variable
aerosol
emissions
constant aerosol
emissions
variable aerosol
emissions
1950-2000
1950-2000
ETH
Varying only SO2 or
BC emissions
Folini et al. in prep.
Research focus: impacts
Impact of dimming on precipitation
in China
Annual mean precipitation
constant aerosol
emissions
ETH
historic aerosol
emissions
Suppression of precipitation with dimming in China
Impact of dimming on precipitation in China
Summer precipitation
total precipitation JJA
constant aerosol emissions
variable aerosol emissions
ETH
convective
large scale
Suppression of convective precipitation with dimming
Research focus: impacts
Impact of SSTs and aerosols on
global land precipitation
ETH
PhD Thesis
Adeline Bichet:
Precipitation
evolution since the
late 19th century
Bichet et al., submitted
Research focus: impacts
Impact of reduced Greenland topography
on precipitation
Change in precipitation
with topography
reduced by 50%
ETH
T106 simulations
Overall increase in precipitation with decreasing
topography
Master Thesis Maria Hakuba
Research focus: scenarios
• How will the Earth energy and water balance
components evolve in the future?
1950 - 2020
Surface clear sky
insolation in NH
midlatitudes
ECHAM5-HAM with
ENSEMBLE SSTs
ETH
Transition into a new dimming?
Coupled model desirable
Future Plans with ECHAM
Research focus on changes in the energy and water
cycles based on multidecadal transient simulations
Near term experiments:
•
Carry out multidecadal transient simulations with new model versions
ECHAM6 and ECHAM6-HAM (sensitivity studies)
•
Use ECHAM6-HAM with new emission inventories from IPCC AR5,
comparison to NIES and other inventories, comparison to earlier ECHAM5HAM simulations
ETH
Mid term experiments:
•
Use a coupled Atmosphere-Ocean version of ECHAM6 (ECHAM6-HAM?) to
study impacts of changes in the radiation balance on various climate system
components including ocean feedbacks.
•
High resolution (T213?) time slice experiments for present and future
climates (e.g. for mass balance changes of polar ice sheets)
All simulation data can be made available to other interested groups
ETH