We estimate the isoprene fluxes emitted by vegetation in recent past and future climate over the European (EURO-CORDEX) domain using the MEGAN-MOHYCAN model (Stavrakou et al. 2014, Müller et al. 2008, Guenther et al. 2006, 2012). We perform simulations using the output of the CORDEX.be ALARO-0 regional climate model (Giot et al., 2016) forced by the RCP2.6, RCP4.5 and RCP8.5 scenarios over 2070-2099, and compare with the emissions from a control simulation over 1976-2005 derived by the same model. The ALARO fields used are temperature, wind, cloud cover fraction, solar radiation downward flux and specific humidity. The units used in the figure below are mg of isoprene /m²/h and the mean emission flux for the entire domain is given inset each panel.

About the model simulations

The datasets are generated in the frame of the CORDEX.be project. In this document you'll find a short discussion on the datasets. The following simulations were conducted:

Simulations using ERA-Interim ECMWF meteorology (1979-2014)

• H1: uses ERA-Interim ECMWF reanalysis meteorological fields (Stavrakou et al. 2014).
• H2: as H1, with adjusted solar radiation fields  based on long-term ground-based solar radiation measurements (Sanchez-Lorenzo et al., 2013).
• H3: as H2, considers the impact of CO₂ inhibition by using the CO₂ inhibition parameterization of Possell and Hewitt (2011).

Simulations using ALARO meteorology (1976-2005 or 2070-2099)

• CTRL: uses output from the regional European climate model ALARO for the period 1976-2005 (Giot et al., 2016)
• climate : uses output from the climate model ALARO for future climate following three RCP scenarios, RCP2.6, RCP4.5 and RCP8.5 (van Vuuren et al., 2011)
• climate + F : as "climate", accounts for the impact of CO₂ fertilisation by simulating the LAI response to CO₂ changes based on Zhu et al. (2016)
• climate + WI : as "climate", accounts for the impact of CO₂ inhibition on the isoprene emissions according to the  parameterization of Wilkinson et al. (2009).
• climate + PH: as "climate", accounts for the impact of CO₂ inhibition by using the CO₂ inhibition parameterization by Possell and Hewitt (2011).
• climate + F + WI :as "climate", accounts for the impact of CO₂ fertilisation (Zhu et al. 2016) and CO₂ inhibition as in Wilkinson et al.,(2009)
• climate + F + PH : as "climate", accounts for the impact of CO₂ fertilisation (Zhu et al. 2016) and CO₂ inhibition as in Possell and Hewitt (2011)
  

Download the data

Isoprene emissions are provided at 0.1x0.1° resolution over the EURO-CORDEX domain (34°N-70°N and 25°W-50°E) in NetCdf format. The historical data (HIST) are annual emissions averaged over 1976-2005 (ALARO) or over 1979-2014 (ECMWF) and all future data (RCP) are annual emissions averaged over 2070-2099.

Table : Mean isoprene emissions for the past and future climate conditions over the EURO-CORDEX domain (2.1MB per file).

The "H3" simulation is the "best" estimate for recent past isoprene emissions (Bauwens et al. 2017). 

• Annual emission estimates during the period 1979-2014 can be downloaded here. (80.0MB)

References

Bauwens, M., Stavrakou, T., Müller, J.-F., Van Schaeybroeck, B., De Cruz, L., De Troch, R., Giot O., Hamdi, R., Termonia, P., Laffineur, Q., Amelynck, C., Schoon, N., Heinesch, B., Holst, T., Arneth, A., Ceulemans, R., Sanchez-Lorenzo, A., and Guenther, A., Recent past (1979-2014) and future (2070-2099) isoprene fluxes over Europe simulated with the MEGAN-MOHYCAN model, Atmos. Chem. Phys., in review.

Guenther, A., Karl, T., Harley, P., Wiedinmyer, C., Palmer, P. I. and Geron, C.: Estimates of global terrestrial isoprene emissions using MEGAN (Model of Emissions of Gases and Aerosols from Nature), Atmos. Chem. Phys., 6, 3181–3210, doi:10.5194/acp-6-3181-2006, 2006 [pdf]

Müller, J.-F., Stavrakou, T., Wallens, S., De Smedt, I., Van Roozendael, M., Potosnak, M. J., Rinne, J., Munger, B., Goldstein, A. and Guenther, A. B.: Global isoprene emissions estimated using MEGAN, ECMWF analyses and a detailed canopy environment model, Atmos. Chem. Phys., 8, 1329–1341, 2008 [pdf]

Possell, M. and Hewitt, C. N.: Isoprene emissions from plants are mediated by atmospheric CO2 concentrations, Global Change Biology, 17(4), 1595–1610, 2011 [pdf]

Sanchez-Lorenzo, A., Wild, M. and Trentmann, J.: Validation and stability assessment of the monthly mean CM SAF surface solar radiation dataset over Europe against a homogenized surface dataset (1983–2005), Remote Sens. Environ., 134, 355–366, 2013 [pdf]

Stavrakou, T., J.-F. Müller, M. Bauwens, I. De Smedt, M. Van Roozendael, A. Guenther, M. Wild, and X. Xia, Isoprene emissions over Asia 1979-2012 : impact of climate and land use changes, Atmos. Chem. Phys., 14, 4587-4605, 2014 [pdf]

 Wilkinson, M. J., Monson, R. K., Trahan, N., Lee, S., Brown, E., Jackson, R. B., Polley, H. W., Fay, P. A. and Fall, R.: Leaf isoprene emission rate as a function of atmospheric CO2 concentration, Global Change Biology, 15(5), 1189–1200, 2009 [pdf]