DOI: 10.5281/zenodo.14257058
title: Biophysical Nexus data vectors for NEXOGENESIS case studies

description: D2.2 aims at delivering Nexus vectors of biophysical data projections  for each case study involved in the NEXOGENESIS (NXG) project, as monthly projections from modelling assessments aggregated from various sources. Climatic, environmental, agricultural-related, and hydrological variables have been listed according to potential case study leaders’ needs, and analytical tool under development in NXG. 

Five climatic and biophysical sources, i.e., ISIMIP, CORDEX, SIMETAW_GIS, C3S, and GLOBIO were used to identify available biophysical data collection and relevant data vectors with projections into the future consolidated from these data sources. Details about these selected sources are provided in NexoGenesis Deliverable 2.1 ("Document information and consolidated data available according to specific Nexus dimensions from Modelling, Repository and Inter-Comparison projects").  The portfolio of consolidated data includes an extensive set of variables with monthly/annual trends from historical over future projections (i.e. 1971-2070) under different radiative forcing (i.e. Representative Concentration Pathways or RCPs) to cover different thematic variables related to four main sectors, i.e., climate, water, agriculture, and ecosystem. RCP 2.6, RCP 6.0 and RCP 8.5 have been chosen as plausible future GHG emission scenarios to test effects of mitigation policies and as probabilistic distribution function for uncertainty analyses. Data is forced with the latest CMIP6 climate projections, in line with IPCC VI report assessment. The biophysical and climate data are derived for the five NXG case studies located in Europe and Africa: 1) Nestos river basin (BG-EL); 2) Lower Danube Basin (RO); 3) Lielupe River basin (LT-LV); 4) Adige River Basin (IT); 5) Inkomati-Usuthu River Basin (ZA). Among these CSs, two are transboundary: Nestos (Greece- Bulgaria) and Lielupe (Latvia- Lituania). A list of variables is reported for each sector, e.g.

i) climate: precipitation, mean temperature, minimum temperature, maximum temperature, wind speed, solar radiation, relative humidity, snowfall etc;

ii) water: surface runoff, subsurface runoff, groundwater runoff, groundwater recharge, total runoff, potential evaporation, soil moisture, reservoir storage, lake storage, irrigation water demand, domestic water demand, industrial water demand, total water demand etc.,

iii) agriculture: planting and harvesting date, nitrogen application, crop yield, biomass growth, irrigation requirement for main staple crops (i.e. maize, wheat, rice, sugarcane, sunflower, sugarbeet, soy, millet, rapeseed, groundnuts, filed peas, cassava). Additional projections of irrigation requirements and yield decline due to water shortage for other crops relevant to case studies are under development with the SIMETAW-GIS platform  

vi) ecosystem: Carbon mass in soil pool, carbon mass in vegetation, Net Primary Productivity, Gross Primary Productivity, fire burnt area, mean species abundance - plants, mean species abundance - birds and mammals, etc.

Biophysical quantitative data for more than 150 variables have been collected, elaborated, and provided so far for each of the Nexog. For each NXG project case study details such as climate drivers, RCPs, and units considered as well as a short description of the variable have been collected in an Excel spreadsheet and uploaded on Zenodo. 

The biophysical data trends provided within the NXG project are generated following uniform modelling sources, modelling simulations, methodology procedure, and assumptions. This contributes to uniform findings in the five case studies, to make them comparable and, when possible, upscalable to other/wider regions.