VPRM-code

Vegetation Photosynthesis and Respiration Model (Mahadevan et al., 2008) in Python For my purposes I at first obtain the surface reflectance data (MOD09A1 v6). The data is derived by The Moderate Resolution Imaging Spectroradiometer (MODIS) which is set up on Terra satellite (for more info and for the data please see https://lpdaac.usgs.gov/products/mod09a1v006/). In my study I used all available MODIS data for the period Mar-Apr 2019 (7 datasets in total with periodicity of 8 days and spatial resolution of 500 m or approximately 0.005°). EVI, LSWI and LSWImax were calculated according to the MODIS data. Air temperature was obtained from ERA5 reanalysis (spatial resolution 0.25°, temporal resolution 3 h). PAR was retrieved from the WRF-Chem simulation (variable SWDOWN – direct short-wave radiation) for the period of Mar-Apr 2019. The air temperature data can be used from the WRF-Chem simulation as well. I prefered the ERA5 due to the fact that I didn`t preserve the simulated air temperature after I made the WRF-Chem simulation. That is why I prefered to use the ERA 5 rather than to run WRF-Chem one more time. Spatial and temporal resolution of WRF-Chem results constituted 0.1° and 3 h respectively. Hereby, spatial and temporal resolution of the VPRM modelling data (0.25° and 3 h) was defined by the crudest resolution of the datasets used to run the model (the air temperature from the ERA 5). After that, using data on land cover type (MODIS product, MCD12Q1; https://lpdaac.usgs.gov/products/mcd12q1v006/) CO2 biospheric fluxes were calculated. Such prior information as Tmin, Tmax, Topt,α, β, λ and PAR0 was derived from the Table 2 of the study [Mahadevan, P., S. C. Wofsy, D. M. Matross, X. Xiao, A. L. Dunn, J. C. Lin, C. Gerbig, J. W. Munger, V. Y. Chow,and E. W. Gottlieb (2008), A satellite-based biosphere parameterization for net ecosystem CO2exchange: Vegetation Photosynthesisand Respiration Model (VPRM),Global Biogeochem. Cycles,22, GB2005, doi:10.1029/2006GB002735] for different vegetation types.