Input Data for Figure 12.9 from Chapter 12 of the Working Group I (WGI) Contribution to the Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report (AR6).

Figure 12.9 shows projected changes in selected climatic impact-driver indices for Europe.

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How to cite this dataset
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When citing this dataset, please include both the data citation below (under 'Citable as') and the following citation for the report component from which the figure originates:
Ranasinghe, R., A.C. Ruane, R. Vautard, N. Arnell, E. Coppola, F.A. Cruz, S. Dessai, A.S. Islam, M. Rahimi, D. Ruiz Carrascal, J. Sillmann, M.B. Sylla, C. Tebaldi, W. Wang, and R. Zaaboul, 2021: Climate Change Information for Regional Impact and for Risk Assessment. In Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [Masson- Delmotte, V., P. Zhai, A. Pirani, S.L. Connors, C. Péan, S. Berger, N. Caud, Y. Chen, L. Goldfarb, M.I. Gomis, M. Huang, K. Leitzell, E. Lonnoy, J.B.R. Matthews, T.K. Maycock, T. Waterfield, O. Yelekçi, R. Yu, and B. Zhou (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, pp. 1767–1926, doi:10.1017/9781009157896.014.

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Figure subpanels
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The figure has four panels, with general data provided in the central directory and specific data in 3 folders (Q100_CMIP5, Q100_CMIP6, Q1000_CORDEX-core).

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List of data provided
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This dataset contains:
- spatial field over Europe of mean change in 1-in-100 year river discharge per unit catchment area (Q100, m3 s-1 km-2) from CORDEX models for 2041-2060 relative to 1995-2014 for RCP8.5
- spatial field of changes of number of days per year with snow water equivalent over 100mm (SWE100) from EURO-CORDEX models for 2041-2060 relative to 1995-2014 for RCP8.5; the grid points with less than 14 days per year with SWE100 during the reference (recent past) period are put to zero.
- the associated mask showing the areas with more than 80% of model agreement in the sign of change
- regional averages in Europe of Q100 (median value and the 10th-90th percentile range of model ensemble values across each model ensemble) over land areas for the WGI reference AR6 regions (defined in Chapter 1) for:
   - CMIP6 historical, ssp126 and ssp585
   - CMIP5 and CORDEX historical, RCP2.6 and RCP8.5
   - for the ‘recent past’ (1995-2014), mid-term (2041-2060) and long-term (2081-2100) time periods
   - and for three global warming levels (defined relative to the preindustrial period 1850-1900): 1.5°C, 2°C and 4°C
- regional averages of number of days per year with snow water equivalent over 100mm (SWE100) in Europe for:
   - CMIP6 historical, ssp126 and ssp585
   - CMIP5 and EURO-CORDEX historical, RCP2.6 and RCP8.5
   - for the ‘recent past’ (1995-2014), mid-term (2041-2060) and long-term (2081-2100) time periods
   - and for three global warming levels (defined relative to the preindustrial period 1850-1900): 1.5°C, 2°C and 4°C
The grid points with less than 14 days per year with SWE100 during the reference (recent past) period are put to zero.

NEU, WCE and MED are domains used in the model.

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Data provided in relation to figure
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Data provided in relation to Figure 12.9:

Panel a:
- Q100_map_panel_a_EUR_divdra.nc: Field (colors plotted on the map) of changes of 1-in-100yr river discharge per unit catchment area between 2041-2060 (mid-term) and 1995-2014 (recent past) for CORDEX RCP8.5;  the file contains the data for the regions from the EUR CORDEX domain

Panel b:
- SWE_panel_b_RCP85_mce_minus_baseline.nc: spatial field (colors) of changes of number of days per year with snow water equivalent over 100mm (SWE100) from EURO-CORDEX models for 2041-2060 relative to 1995-2014 for RCP8; the grid points with less than 14 days per year with SWE100 during the reference (recent past) period are put to zero
- mask_80perc-agreement_SWE_panel_b_RCP85_mce_minus_baseline.nc: spatial mask (for hatching) showing where at least 80% of the models agree in terms of sign of change (negative change, positive change or zero change); values are: 1 where true, 0 where false

Panel c:
- txt files containing the median and 5th/95th percentiles of each ensemble of the 1-in-100yr river discharge per unit catchment area (Q100) regional averages of time slices: Q100_${ensemble}/Q100_${scenario}_${period}.nc_${CORDEX_domain}.txt, with:
    - ${ensemble}: CMIP5, CMIP6 or CORDEX-core
    - ${scenario}: the name of the scenario : ssp126, ssp585, rcp26, rcp85
    - ${period}: the explicit period used to compute the temporal average: 1995-2014 (recent past), 2041-2060 (mid-term) and 2080-2099 (long term)
    - ${CORDEX_domain}: the CORDEX domain
- txt files containing the Q100 regional averages of global warming levels: Q100_${ensemble}/${GWL}_${CORDEX_domain}.txt, with:
    - ${ensemble}: CMIP5, CMIP6 or CORDEX-core
    - ${GWL}: the Global Warming Level: 1.5, 2 or 4
    - ${CORDEX_domain}: the CORDEX domain

Panel d:
- CMIP5_EUR-11_snw_mask14_AR6_regional_averages.json: regional averages for the CMIP5 multimodel ensemble of number of days per year with snow water equivalent over 100mm (SWE100) in Europe for recent past (1995-2014), mid-term (2041-2060) long-term (2081-2099) for RCP2.6 and RCP8.5, and for three global warming levels: 1.5, 2 and 4; the file contains the median (dots in the subpanels) and the 5th (q5) and 95th (q95) uncertainty estimates (used to plot the vertical bars)
- EURO-CORDEX_SWE_mask14_AR6_regional_averages.json: same as previous file for the EURO-CORDEX multimodel ensemble
- CMIP6_EUR-11_snw_mask14_AR6_regional_averages.json: same as previous file for CMIP6 (ssp126 instead of RCP2.6 and ssp585 instead of RCP8.5)

CORDEX is The Coordinated Regional Downscaling Experiment from the WCRP.

CMIP5 is the fifth phase of the Coupled Model Intercomparison Project.

CMIP6 is the sixth phase of the Coupled Model Intercomparison Project.

SSP stands for Shared Socioeconomic Pathway.

SSP126 is the Shared Socioeconomic Pathway which represents the lower boundary of radiative forcing and development scenarios, consistent with RCP2.6.

SSP585 is the Shared Socioeconomic Pathway which represents the upper boundary of radiative forcing and development scenarios, consistent with RCP8.5.

RCP stands for Representative Concentration Pathway.

RCP2.6 is the Representative Concentration Pathway for 2.6 Wm-2 global warming by 2100.

RCP8.5 is the Representative Concentration Pathway for 8.5 Wm-2 global warming by 2100.

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Notes on reproducing the figure from the provided data
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For panel a, the plotting script (see data tables and code on Github) draws the rivers and uses a subroutine to identify the rivers to plot them individually with lines; plotting the Q100 netcdf file will produce dots (and not rivers).

For panel c, the recent past values are plotted as absolute values (left column on each regional subpanel) and the future changes are plotted as differences against the recent past values (differences are computed when plotting the values).

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Sources of additional information
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The following weblinks are provided in the Related Documents section of this catalogue record:
- Link to the figure on the IPCC AR6 website
- Link to the report component containing the figure (Chapter 12)
- Link to the Supplementary Material for Chapter 12, which contains details on the input data used in Table 12.SM.1
- Link to the code for the figure, archived on Zenodo.