The experiment CLM_A2_ZS contains Northern European regional climate simulations of the years 2070-2099 on a rotated grid (CLM non hydrostatic, 0.44 deg. hor. resolution, see http://www.clm-community.eu ). It is forced by the first (_1_) run of the global IPCC SRES A2 (EH5-T63L31_OM-GR1.5L40_A2_1_6H), which describes an economic development which is primarily regionally oriented and the technical change is more fragmented and slower than in the other SRES storylines. The model region starts at -19.36/-40.48 (lat/lon in rotated coordinates; centre of lower left corner of the domain) with rotated North Pole at 21.3/-175.0 (lat/lon). The number of grid points is 80/146 (lat/lon). The sponge zone (numerically unreliable boundary grid points) consists of 8 grid boxes at each border. EH5-T63L31_OM-GR1.5L40_A2_1_6H were nudged during the simulations (spectral nudging,von Storch, H., A spectral nudging technique for dynamical downscaling purposes. Mon. Wea. Rev, 2000 ) The regional model variables include two-dimensional near surface fields and atmospheric fields on 6 pressure levels (200, 500, 700, 850, 925 and 1000 hPa) for zonal and meridional wind, temperature and pressure. The time interval of the output fields is 3 hours. Please contact sga"at"dkrz.de for data request details. The output format is netCDF. Experiment with CLM 2.4.6 on HPC Cluster ( blizzard ).

Simulated 2D residual velocity fields in the inner German Bight were subjected to Principal Component Analysis (PCA). Residual currents were obtained from coastDat2 barotropic 2D simulations with the hydrodynamic model TRIM-NP V2.1.22 in barotropic 2D mode on a Cartesian grid (1.6km spatial resolution) stored on an hourly basis for the years 1948 - 2012 (doi:10.1594/WDCC/coastDat-2_TRIM-NP-2d) and later extended until August 2015. The present analysis refers to the period Jan 1958 - Aug 2015. The spatial domain considered is the region to the east of 6 degrees east and to the south of 55.6 degrees north. All grid nodes with a bathymetry of less than 10m were excluded. Residual velocities were calculated in two different ways: 1.) as 25h means, 2.) as monthly means. Both types of residual current data are available from * RESIDUAL_CURRENTS_195801_201508 The directory contains sub-directories for years and months. Daily residual currents for the 13th of September 1974, for instance, are stored in * RESIDUAL_CURRENTS_195801_201508/YEAR_1974/MONTH_09/TRIM2D_1974_09_13_means.nc while monthly mean residual currents for September 1974 are stored in: * RESIDUAL_CURRENTS_195801_201508/YEAR_1974/TRIM2D_1974_09_means.nc All current fields provided were interpolated from the original Cartesian model grid to a more convenient regular geographical grid (116x76 nodes). Mean residual currents are stored in: * mean_residual_currents.nc This data set contains residual velocities both on original Cartesian grid nodes and interpolated to the geographical grid. An example plot is provided: * mean_residual_currents.png For PCA, two residual velocity components from each of 12133 Cartesian grid nodes were combined into one data vector (length 2x12133), referring to 21061 daily or 692 monthly time levels. Results of two independent PCAs for either daily or monthly mean fields are stored in: * PCA_daily_residual_currents.nc * PCA_monthly_residual_currents.nc Files contain three leading Principal Components (PCs) and corresponding Emipirical Orthogonal Functions (EOFs). Again EOFs were also interpolated to a regular geographical grid. PC time series are also stored in plain ASCII format: * PCs_daily.txt * PCs_monthly.txt For monthly fields the number N of variables (N=2x12133) is much larger than the number T of time levels (T=692). Therefore, to reduce computational demands, the roles of time and space were formally interchanged. Having conducted the PCA the EOFs were then transformed back to the original spatial coordinates (cf. Section 12.2.6 in von Storch and Zwiers (1999), Statistical Analysis in Climate Research, Cambridge University Press). A much larger number of time levels made even this approach prohibitive for the full set of daily data. Therefore, PCAs were performed for six sub-periods (1958-1965, 1966-1975, 1976-1985, 1986-1995, 1996-2005, 2006-2015(Aug)) independently. EOFs obtained from these six sub-periods were then averaged to obtain EOFs representative for the whole period. Corresponding PCs were calculated by projecting daily fields onto these average EOFs. IMPORTANT: In contrast with PCA of monthly data, the PCA of daily data INVOLVES SOME APPROXIMATIONS! EOFs on the original nodes were normalized to have unit lengths. The following figures, * daily_EOF1.png * daily_EOF2.png * daily_EOF3.png show the first three EOFs obtained from daily data, assuming that corresponding PCs have the value of one standard deviation. The following two plots, * monthly_EOF1.png * monthly_EOF2.png show the leading EOFs for monthly mean data. EOF3 is omitted as it represents just a very small percentage of overall variance (1.7%).

The experiment contains baroclinic hindcast simulations of the North Sea by the hydrodynamic model HAMSOM (Pohlmann, 2006) for the period 1948-2007. HAMSOM was set up at a spatial resolution of 20' x 12' and with 19 vertical levels (5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 60, 75, 100, 150, 200, 250, 350, 600 and 1000m, lower boundary level). The data-set contains hourly output of temperature, salinity, u- and v-component (3-dim) and water level (2-dim). At the open boundaries, lateral boundary conditions are obtained from a coarser, large-scale Northwest-European shelf sea model driven by climatological temperature and salinity obtained from Levitus (1982). For water levels, in addition the eight significant tidal constituents (M2, S2, N2, K2, K1, O1, Q1 and P1) are included and weather effects are accounted for by using wind and pressure fields from the NCEP/NCAR Reanalysis 1 (Kalnay et al., 1996). Due to technical reasons at the lateral boundaries the water level was added by 0.5m. Atmospheric forcing was obtained from NCEP/NCAR Reanalysis 1 data-set comprising near-surface air-temperature, humidity, cloud cover, precipitation, sea level pressure and near surface wind speed and direction. The output format is netCDF.

The experiment CLM_C20_2_D2 contains European regional climate simulations of the years 1960-2000 on a rotated grid (CLM non hydrostatic, 0.165 degree hor. resolution, see http://www.clm-community.eu ). The simulations of the 20th century (1960-2000) have been forced by the second (_2_) run of the global 20th century climate (EH5-T63L31_OM-GR1.5L40_20C_2_6H) with observed anthropogenic forcing. In data stream 2 (_D2) the output variables of CLM are stored as time series on a rotated grid. The model region starts at -20.8725/-23.7275 (lat/lon in rotated coordinates; centre of lower left grid box) with an increment of 0.165 degree. The position of the North Pole in the rotated grid is: 39.25/-162.0 (lat/lon). The number of grid points is 255/241 (lat/lon). The sponge zone (numerically unreliable boundary grid points) of the original model output has been cut off. The regional model variables include two-dimensional near surface fields, as well as soil and atmospheric fields on different layers. The soil fields are simulated on 10 different levels with a maximum depth of 15 meters. The atmospheric fields are given on 6 pressure levels (200, 500, 700, 850, 925 and 1000 hPa). The time interval of the output fields ranges from 1 to 3 hours and includes daily output fields, depending on the respective variables. Please contact sga"at"dkrz.de for data request details. See http://sga.wdc-climate.de for more details on CLM simulations in the context of the BMBF funding priority "klimazwei", some useful information on handling climate model data and the data access regulations. The output format is netCDF Experiment with CLM 2.4.11 on NEC-SX6(hurrikan) raw data: hpss:/dxul/ut/k/k204095/prism/experiments/C20_2

The experiment CLM_C20_3_D2 contains European regional climate simulations of the years 1960-2000 on a rotated grid (CLM non hydrostatic, 0.165 degree hor. resolution, see http://www.clm-community.eu ). The simulations of the 20th century (1960-2000) have been forced by the third (_3_) run of the global 20th century climate (EH5-T63L31_OM-GR1.5L40_20C_3_6H) with observed anthropogenic forcing. In data stream 2 (_D2) the output variables of CLM are stored as time series on a rotated grid. The model region starts at -20.8725/-23.7275 (lat/lon in rotated coordinates; centre of lower left grid box) with an increment of 0.165 deg. The position of the North Pole in the rotated grid is: 39.25/-162.0 (lat/lon). The number of grid points is 255/241 (lat/lon). The sponge zone (numerically unreliable boundary grid points) of the original model output has been cut off. The regional model variables include two-dimensional near surface fields, as well as soil and atmospheric fields on different layers. The soil fields are simulated on 10 different levels with a maximum depth of 15 meters. The atmospheric fields are given on 6 pressure levels (200, 500, 700, 850, 925 and 1000 hPa). The time interval of the output fields ranges from 1 to 3 hours and includes daily output fields, depending on the respective variables. Please contact sga"at"dkrz.de for data request details. See http://sga.wdc-climate.de for more details on CLM simulations in the context of the BMBF funding priority "klimazwei", some useful information on handling climate model data and the data access regulations. The output format is netCDF Experiment with CLM 2.4.11 on NEC-SX6 (Stuttgart) raw data: /ut/6/k204095/imdi/experiments/C20_3/outdata/clm

The experiment CLM_A1B_ZS contains Northern European regional climate simulations of the years 2070-2099 on a rotated grid (CLM non hydrostatic, 0.44 deg. hor. resolution, see http://www.clm-community.eu ). It is forced by the first (_1_) run of the global IPCC SRES A1B (EH5-T63L31_OM-GR1.5L40_A1B_1_6H), which describes a possible future world of very rapid economic growth, global population peaking in mid-century and rapid introduction of new and more efficient technologies with a balance across all energy sources. The model region starts at -19.36/-40.48 (lat/lon in rotated coordinates; centre of lower left corner of the domain) with rotated North Pole at 21.3/-175.0 (lat/lon). The number of grid points is 80/146 (lat/lon). The sponge zone (numerically unreliable boundary grid points) consists of 8 grid boxes at each border. EH5-T63L31_OM-GR1.5L40_A1B_1_6H were nudged during the simulations (spectral nudging,von Storch, H., A spectral nudging technique for dynamical downscaling purposes. Mon. Wea. Rev, 2000 ) The regional model variables include two-dimensional near surface fields and atmospheric fields on 6 pressure levels (200, 500, 700, 850, 925 and 1000 hPa) for zonal and meridional wind, temperature and pressure. The time interval of the output fields is 3 hours. Please contact sga"at"dkrz.de for data request details. The output format is netCDF. Experiment with CLM 2.4.6 on HPC Cluster ( blizzard ).

The experiment CLM_A1B_1_D2 contains European regional climate simulations of the years 2001-2100 on a rotated grid (CLM non hydrostatic, 0.165 deg. hor. resolution, see http://www.clm-community.eu ). It is forced by the first (_1_) run of the global IPCC scenario A1B (EH5-T63L31_OM-GR1.5L40_A1B_1_6H), which describes a possible future world of very rapid economic growth, global population peaking in mid-century and rapid introduction of new and more efficient technologies with a balance across all energy sources. In data stream 2 (_D2) the output variables of CLM are stored as time series on a rotated grid. The model region starts at -20.8725/-23.7275 (lat/lon in rotated coordinates; centre of lower left grid box) with rotated North Pole at 39.25/-162.0 (lat/lon). The number of grid points is 255/241 (lat/lon). The sponge zone (numerically unreliable boundary grid points) of the original model output has been cut off. The regional model variables include two-dimensional near surface fields, as well as soil and atmospheric fields on different layers. The soil fields are simulated on 10 different levels with a maximum depth of 15 meters. The atmospheric fields are given on 6 pressure levels (200, 500, 700, 850, 925 and 1000 hPa). The time interval of the output fields ranges from 1 to 3 hours and includes daily output fields, depending on the respective variables. Please contact sga"at"dkrz.de for data request details. See http://sga.wdc-climate.de for more details on CLM simulations in the context of the BMBF funding priority "klimazwei", some useful information on handling climate model data and the data access regulations. The output format is netCDF Experiment with CLM 2.4.11 on NEC-SX6(hurrikan) raw data: hpss:/dxul/ut/k/k204095/prism/experiments/A1B_1

High RESolution Atmospheric Forcing Fields (HiResAFF) consist of key meteorological variables on daily scale which are typically used to drive ocean or ecosystem models. The fields are reconstructed through non-linear statistical upscaling using the analog-method (Schenk and Zorita, 2012). The method resamples atmospheric fields from a regional climate model (RCAO/RCA3) in time based on the best pattern similarity in the predictor space of homogenous historical station data since 1850. The dataset provides physically consistent homogeneous atmospheric fields suitable to derive long-term simulations and statistical analysis since 1850 over the North Sea and Baltic Sea region of Europe. The analog-method and reconstruction skill is described in Schenk and Zorita (2012) and the extended dataset to 1850 in Schenk (2015). The research leading to these results has received funding from the European Union Seventh Framework Programme (FP/2007-2013) under grant agreement no. 217246 made with the joint Baltic Sea research and development programme BONUS, and the German Federal Ministry of Education and Research (03F0492A).

The experiment CLM_B1_2_D2 contains European regional climate simulations of the years 2001-2100 on a rotated grid (CLM non hydrostatic, 0.165 deg. hor. res., see http://www.clm-community.eu ). It is forced by the second (_2_) run of the global IPCC scenario B1 (EH5-T63L31_OM-GR1.5L40_B1_2_6H), which describes a possible future world with global population peaking in mid-century and rapid change in economic structures towards a service and information economy. An introduction of clean and resource efficient technologies was assumed. In data stream 2 (_D2) the output variables of CLM are stored as time series on a rotated grid. The model region starts at -20.8725/-23.7275 (lat/lon in rotated coordinates; centre of lower left grid box) with rotated North Pole at 39.25/-162.0 (lat/lon). The number of grid points is 255/241 (lat/lon). The sponge zone (numerically unreliable boundary grid points) of the original model output has been cut off. The regional model variables include two-dimensional near surface fields, as well as soil and atmospheric fields on different layers. The soil fields are simulated on 10 different levels with a maximum depth of 15 meters. The atmospheric fields are given on 6 pressure levels (200, 500, 700, 850, 925 and 1000 hPa). The time interval of the output fields ranges from 1 to 3 hours and includes daily output fields, depending on the respective variables. Please contact sga"at"dkrz.de for data request details. See http://sga.wdc-climate.de for more details on CLM simulations in the context of the BMBF funding priority "klimazwei", some useful information on handling climate model data and the data access regulations. The output format is netCDF Experiment with CLM 2.4.11 on NEC-SX6(hurrikan) raw data: hpss:/dxul/ut/k/k204095/prism/experiments/B1_2

The experiment CLM_20C_ZS contains Northern European regional climate simulations of the years 1960-1989 on a rotated grid (CLM non hydrostatic, 0.44 deg. hor. resolution, see http://www.clm-community.eu ). It is forced by the first (_1_) run of the global IPCC SRES 20C (EH5-T63L31_OM-GR1.5L40_20C_1_6H). The data represent 6 hourly values of a 20th century simulation with observed anthropogenic forcings (CO2, CH4, N2O, CFCs, O3 and sulfate). The model region starts at -19.36/-40.48 (lat/lon in rotated coordinates; centre of lower left corner of the domain) with rotated North Pole at 21.3/-175.0 (lat/lon). The number of grid points is 80/146 (lat/lon). The sponge zone (numerically unreliable boundary grid points) consists of 8 gridboxes at each border. EH5-T63L31_OM-GR1.5L40_20C_1_6H were nudged during the simulations (spectral nudging,von Storch, H., A spectral nudging technique for dynamical downscaling purposes. Mon. Wea. Rev, 2000 ) The regional model variables include two-dimensional near surface fields and atmospheric fields on 6 pressure levels (200, 500, 700, 850, 925 and 1000 hPa) for zonal and meridional wind, temperature and pressure. The time interval of the output fields is 3 hours. Please contact sga"at"dkrz.de for data request details. The output format is netCDF. Experiment with CLM 2.4.6 on HPC Cluster ( blizzard ).