Organics Working Group
All users interested in the GEOS-Chem organic simulations (e.g. isoprene, etc) are encouraged to subscribe to the organics email list (click on the link in the contact information section below).
|Organics Working Group Co-Chairs||Dylan Millet and Emily Fischer|
|Organics Working Group email email@example.com|
|To subscribe to email list||Send email to firstname.lastname@example.org|
|To unsubscribe from email list||Send email to email@example.com|
Current Organics Projects (please add yours!)
|Simulation||User Group||Description||Contact Person||Date Added|
|Projects using offline simulations|
|COS||U. East Anglia||Atmospheric budget of COS||Parvadha Suntharalingam||09 Jun 2009|
|Methanol adjoint||U. Minnesota||Adjoint inversion of global methanol sources using TES satellite data||Kelley Wells, Dylan Millet||18 Jun 2013|
|Acetone||Peking U.||Global atmospheric acetone budget and impact of air-sea exchange||May Fu||3 May 2011|
|Projects using full-chemistry simulations|
|full chemistry||U. Minnesota||Isoprene impacts in the Central US inferred from tall tower measurements||Lu Hu, Dylan Millet||18 Jun 2013|
|full chemistry||U. Minnesota||Constraints on US sources of aromatics based on tall tower measurements||Lu Hu, Dylan Millet||18 Jun 2013|
|full chemistry||U. Minnesota||Global budget of aromatic compounds||Dylan Millet||18 Jun 2013|
|full chemistry||U. Minnesota||Sources of organic acids from in situ and space-based measurements||Sree Chaliyakunnel, Dylan Millet||18 Jun 2013|
|full chemistry||U. Wollongong||Using GEOS-Chem to interpret FTIR measurements of CO and HCHO||Rebecca Buchholz||12 May 2011|
|full chemistry||U. Wollongong||Southern Hemisphere intercomparison of CO and HCHO in CTMs and CCMs||Jenny Fisher||8 May 2013|
|full chemistry||U. Wollongong||Evaluating isoprene chemistry in the southeast US using SEAC4RS data||Jenny Fisher (+many others)||28 May 2014|
|full chemistry||Harvard||PAN sources and sinks||Emily Fischer||18 June 2013|
|full chemistry||Harvard||Long-term satellite HCHO trends||Eloise Marais||27 April 2014|
|full chemistry||Univ. of York||Comparisons between ACE-FTS measurements and GEOS-Chem||Gonzalo Gonzalez Abad||12 May 2012|
|full chemistry||Harvard||Constraining isoprene emissions over Africa using OMI HCHO satellite observations||Eloïse Marais||25 Oct 2010|
|full chemistry||Harvard||Implementing CO2 inhibition of isoprene emissions in MEGAN||Amos Tai||05 Jun 2012|
|full chemistry||Harvard||Variability of HCHO Over the Southeastern United States Observed from Space||Lei Zhu||07 May 2013|
|Modified full chem (dicarbonyl)||Peking University||Dicarbonyls and SOA||May Fu||26 Jun 2009|
|Peking University||OMI HCHO and Asian air quality||May Fu||26 Jun 2009|
and full chemistry
|Duke||CO sources from biomass burning (cross-listed under Carbon Cycle WG)||Prasad Kasibhatla||15 Jun 2009|
|U. Edinburgh||Biomass burning studies using satellite data||Siegfried Gonzi||10 Jun 2009|
|U. Edinburgh||Quantifying the impact of boreal forest fires on tropospheric oxidants over the Atlantic||Mark Parrington||10 Jun 2009|
|Tagged CO||U. Edinburgh||Quantifying the impact of boreal forest fires on tropospheric oxidants over the Atlantic||Douglas Finch||01 Oct 2012|
|U. Leicester||Biogenic VOC emissions from tropical ecosystems||Michael Barkley||12 May 2011|
--Dbm 16:12, 18 June 2013 (EDT)
Recently Completed Projects (please add yours!)
|Simulation||User Group||Description||Contact Person||Publication
|full chemistry||U. Minnesota||North American acetone sources determined from tall tower measurements and inverse modeling||Lu Hu, Dylan Millet||Atmos. Chem. Phys., 13, 3379-3392, 2013. PDF|
|full chemistry||U. Minnesota||Natural and anthropogenic ethanol sources in North America||Dylan Millet||Environ. Sci. Technol., 46, 8484-8492, 2012. PDF|
|offline||U. Minnesota||Seasonal cycle of temperate methanol emissions based on satellite data||Kelley Wells, Dylan Millet||Atmos. Chem. Phys., 12, 5897-5912, 2012. PDF|
|offline||U. Minnesota||Sources and seasonality of atmospheric methanol based on tall tower measurements in the US Upper Midwest||Lu Hu, Dylan Millet||Atmos. Chem. Phys., 11, 11145-11156, 2011. PDF|
|full chemistry||Caltech||Monoterpenes and sesquiterpenes and SOA (Sesquiterpene emission update in pipeline for GEOS-Chem standard version)||Havala Pye||Atmos. Chem. Phys., 10, 11261–11276, 2010. PDF|
|full chemistry||Harvard University||The role of the ocean in the global atmospheric budget of acetone||Emily Fischer||GRL., VOL. 39, L01807, doi:10.1029/2011GL050086, 2012 |
--Dbm 14:05, 12 May 2011 (EDT)
|Dicarbonyls simulation||Merge May Fu's dicarbonyl simulation with Caltech isoprene chemistry (which is now standard)||Implement this once flexible chemistry scheme is in place.|
|Update to MEGAN2.1||Described here. The update applies emission algorithm updates according to Guenther et al. (Geosci. Model Dev., 5, 1471–1492, 2012), enables computation of emissions for more compounds, uses CLM4 plant functional type distributions, facilitates computing emissions with different/dynamic land cover schemes, and streamlines the code.||Ready to go in (D. Millet, Univ. of Minnesota)|
|CO2 direct effect on isoprene emissions||Ready to go in (A. Tai, MIT)|
|3D VOC source for tagged CO simulation and enhanced tagging of secondary CO||Secondary CO source in tagged CO simulation is 2D and inconsistent with full chemistry treatment||Under development (J. Fisher, Univ. of Wollongong)|
|HCN simulation||Currently out of date. Update based on Li et al. (ACP, 9, 8531–8543, 2009).||Under development (D. Jones, Univ. of Toronto)|
|Updated LAI||We are currently using a MODIS LAI product that has only been generated through 2008. Need to find or create suitable replacement.||Under development (K. Bowman, JPL; F. Boersma, KNMI)|
|PAN / organics updates||This simulation includes improved treatment of many NMVOCs. There are also changes to how biomass burning emissions are incorporated into the model. The improved PAN simulation, which is based on v9.01.01, has been merged with v9.02h and should be ready to be implemented with v9.03 when requested by support team.||Ready to go in (E. Fischer, CSU)|
|Criegee intermediates||Explicit treatment of criegees||Ready to go in (D. Millet, Univ. of Minnesota)|
|Merge organics from specialized simulations into the mainline code||Pending FlexChem implementation (D. Millet, Univ. of Minnesota)
--Dbm 16:11, 18 June 2013 (EDT)
The following development items have recently been added to GEOS-Chem:
|v9-01-03||Dec 2011||Reactive uptake of VOCs based on Karl et al. (Science, 330, 816-819, 2010)||Jingqiu Mao|
|v9-01-02||Sep 2012||Fix air-sea exchange of acetone and update terrestrial biogenic emissions to MEGAN||Emily Fischer|
|v9-01-02||Sep 2012||Retire GEIA biogenic VOC emissions; MEGAN is now state of the science||Emily Fischer|
|v9-01-02||Nov 2011||Fix for GEIA scaling factor over S. Africa. Prevent excessive emissions due to near-zero flux for baseline year.||Dylan Millet|
|v9-01-02||Nov 2011||RETRO anthropogenic VOC emissions now implemented. It will exist as the default, but GEIA anthropogenic emissions will still be included as an option for some time.||Dylan Millet|
--Dbm 16:12, 18 June 2013 (EDT)
GEIA anthropogenic scaling factors
This update was tested in the 1-month benchmark simulation v9-01-02h and approved on 12 Aug 2011.
A bug was discovered with the annual scale factors for anthropogenic emissions that get applied in anthroems.f (FLIQCO2), which take a ratio between the base year for the GEIA emissions (1985) and the simulation year. For southern Africa (Botswana region) 1985 scale value is abnormally low (<0.03), so that the (current year):1985 ratio ends up being very large (>500) and giving unrealistically high CO and hydrocarbon emissions.
In the scaling file (../GEOS_1x1/anth_scale_factors_200911/CO-AnnualScalar.geos.1x1), scale factors over Botswana increase by a factor of >100 between 1985 and 1990 (i.e. nearly tripling every year), and then more gradually and reasonably after that. As a fix I've created an updated version of the file CO-AnnualScalar.geos.1x1, which is here. The new file is the same as the old one except that the offending values over Botswana for 1985 have been replaced with their 1990 values. This brings things more in line with the surrounding countries.
It's possible there is a more accurate way to do this (e.g. scaling the 1990 values down by some amount to get back to 1985) but until someone looks at this specific region in detail (in which case one may not want to use GEIA anthropogenic emissions anyway) I think this is a good approach and should get rid of the problem.
Emily Fischer ran some comparisons before and after the fix. She writes:
- I have posted some comparison plots for you to look through. I did a one-month test run using the file that you sent me last week. The "before" run has my updates to the ocean acetone source/sink included. For the hydrocarbons, I have before and after plots for surface mixing ratios. Note the very different scales in some cases. Your fix certainly is an improvement. I have included standard difference plots for CO, PAN and acetone.
The discussion about known issues in the dicarbonyls simulation has now been moved to our separate Dicarbonyls simulation wiki page.
--Bob Y. 11:50, 28 April 2011 (EDT)
- A description of MEGAN as implemented in GEOS-Chem up to v8-02-03 is posted HERE.
- The discussion about the implementation of MEGAN 2.1 into GEOS-Chem v8-02-04 has been moved to a separate MEGAN biogenic emissions wiki page.
- An update to the latest MEGAN 2.1 as described in Guenther et al. (2012) is now available and discussed here.
--Dbm 16:18, 18 June 2013 (EDT)