chemistry-climate working group 2013-2017 co-chairs: hong liao, shiliang wu the 7th international...
TRANSCRIPT
Chemistry-climate working group2013-2017 Co-chairs: Hong Liao, Shiliang Wu
The 7th International GEOS-Chem Meeting (IGC7)
Chemistry-climate interactions
ClimateAtmospheric
Chemistry
Ecosystems
Interactions on interannual, decadal, or centennial time scales
Radiative forcing by GHGs,O3, and aerosols
Changes in emissions,chemical reactions, transport,and deposition
Depositionof O3, N, S, etc.
Biogenic VOCs,fire emissions, etc.
Impacts on landcover, etc.
Carbon cycle, etc.
Assimilated meteorologyGEOS-4, GEOS-5, MERRA
GEOS-Chem
Land cover model
Archived meteorology
Fire prediction model
Climate models
Model frameworks
1. Standard
2. Global Change and Air Pollution (GCAP)
Impacts of climate change on land cover (biogenic emissions),fire emissions, and atmospheric chemistry.
Impacts of climate variability on atmospheric chemistry on interannual to decadal time scales.
GEOS-Chem
The standard GEOS-Chem has been used to understand historical changes in atmospheric Chemistry
• To quantify the variations in chemical species;
• To understand the drivers (meteorological parameters vs. emissions) of the variations of different species;
• To help with the interpretation of year-by-year variations in measurements;
• To assess the effectiveness of short-term air quality control strategies.
Mu and Liao, 2014Yang et al., 2014Yang et al., 2015
The GCAP model framework can be used to investigate past and future atmospheres
Three versions of GCAP are available:
1. GISS Model 3 + GEOS-Chem (4o x 5o, by Loretta Mickley in year 2003)
2. GISS Model E + GEOS-Chem (2o x 2.5o or 4o x 5o, by L. T. Murray and E. M. Leibensperger in year 2014)
3. CESM + GEOS-Chem (2o x 2.5o, by Rokjin Park in year 2014)
GCAP has been used extensively for projection of future air quality
1. GCAP: Future changes in air quality and tranboundary transport
Wang et al., 2013; Jiang et al., 2013; Wai et al., 2014
2. GCAP + changes in land cover
Wu et al., 2012; Tai et al., 2013.
3. GCAP + changes in fire emissions
Yue et al., 2013; 2014
2000-2050 increase in surface ozone over Asia due to changes in emissions + climate. Wang et al., 2013.
2050s – present-day
Past fire emissions
Sensitivity of biogenic isoprene emissions to atmospheric [CO2]
Isoprene photochemistry
HO2 uptake by aerosols
Lightning NOx emissions
Murray et al., 2014; Achakulwisut, in review.
[GHGs] Orbital parameters Topography Sea ice extent Sea surface temp.
Climate
GISS Model E GCM
Meteorological fields for 4 time-slices: Present day: ca. 1990sPre-industrial: ca. 1770swarm LGM: ~21kacold LGM: ~21ka
GCAP2 has been applied to paleo- and preindustrial simulations
GCAP3
GACP 3 has been used to study future O3 and oxidants under the RCPs
Kim et al., 2015
RCP2.6 O3 2050-2000 RCP4.5 O3 2050-2000
RCP6.0 O3 2050-2000 RCP8.5 O3 2050-2000
Updates in GEOS-Chem that are important for chemistry-climate
Online radiative transfer model --- The Rapid Radiative Transfer Model for GCMs (RRTMG) has been coupled online with the GEOS-Chem model as described by Heald et al. (2014);
--- The RRTMG solves the radiative transfer equation in shortwave bands and 16 longwave bands that cover from 230 nm through 56 μm.
RCP future emission scenarios in GEOS-Chem (Holmes et al., 2013)
Heald et al. (2014)
Future directions: The two-way coupling of chemistry-climate
1. Coupling of the grid-independent GEOS-Chem with climate models will allow us to easily link chemistry with climate, vegetation, ocean biology, fire, carbon cycle .
2. On-line interface between GEOS-Chem and the Goddard Earth Observing System (GEOS) Earth System Model from the NASA Global Modeling and Assimilation Office (GMAO) is ready, using the Earth System Modeling Framework (ESMF);
3. Can the GEOS-Chem simulations be conducted on any model grid and interfaced with any ESM?