DOI: 10.5281/zenodo.16992762
title: Data supplement for Oliver et al. "The North Atlantic sub-polar gyre and phytoplankton bloom under potential future climate scenarios"

description: %% Data supplement for the analysis for journal article:

%

% The North Atlantic sub-polar gyre and phytoplankton bloom under potential future climate scenarios

%

% Sophy Oliver1, Andrew Yool1, Lee de Mora2, Stephen Kelly1, Spencer K. Liddicoat3, Alexandra Loveridge1, Robin S. Smith4, Ekaterina Popova1

% 1 National Oceanography Centre, Southampton SO14 3ZH, UK

% 2 Plymouth Marine Laboratory, Plymouth, PL1 3DH, UK 

% 3 Met Office Hadley Centre, Exeter, United Kingdom

% 4 Department of Meteorology, NCAS, University of Reading, Reading, United Kingdom

%

% Corresponding author: Sophy Oliver (sophy.oliver@noc.ac.uk)

%

% Submitted August 2025

 

Data supplement contents:

- code: MATLAB post processing and plotting scripts, all called from main.m

- data: model grid mask information

- post_processed_data: model data generated by the code, and used for plotting

- Plots: results (figures and tables) generated by code

 

Here's a more in-depth breakdown of each sub-directory:

 

code *************************************************************************************

- main.m: Main script organising the workflow of post-processing. This script calls all the functions/scripts below.

- extractOvershootRun2D.m Extract 2D annual statistics from monthly .nc files (input data not provided - for transparency only)

- extractOvershootRun3D.m Extract 3D annual statistics from monthly .nc files (input data not provided - for transparency only)

- create_SPG_contour.m Create SPG region

- calcRegionalMeans.m Extract 2D regional means

- plot_cumulative_emissions.m Calculate cumulative emissions

- subplot_overshoots.m Plot each subplot of combined Figure 1

- plot_rampup_vs_obs.m Plot Figure 2 (model validation)

- plot_rampup_SSH_MLD.m Plot Figure S2 (compare SSH and MLD)

- create_trend_results.m Calculate trends and time to recovery (Figures S3-5, Tables 1 and S1), using method 1 of trend calculation.

Duplicate script create_trend_results_method2.m does the same but using method 2 for trend calculation.

- create_trend_maps.m Plot maps of trends (Figures 3, 5, 6, S6, S7)

- calc_all_trends_in_region.m Calculate trends required for composite Figure 4, using method 1 of trend calculation

Duplicate script calc_all_trends_in_region_method2.m does the same but using method 2 for trend calculation.

- create_composite_figure.m Plot composite Figure 4 panels

Duplicate script create_composite_figure_method2.m does the same but using method 2 for trend calculation.

- plot_hystereses_manuscript.m Plot hysteresis Figure 9

- plot_maps.m Plot Figures 7, S8, S9, S11

- calcRegionalMeans3D.m Extract 3D regional means (input data not provided - for transparency only)

- calculateDensity3D.m Calculate density (input data not provided - for transparency only)

- plot_hov.m Hovmoller plot Figure 8

 

data *************************************************************************************

- nemo_mask100e_ARCTIC.mat MATLAB data file containing model grid basin mask

1-degree, tripolar, focused equatorial resolution

Latitude and longitude are the midpoints of the grid cells

- nemo_area100e.mat MATLAB data file containing the grid cell areas (m^2)

 

post_processed_data **********************************************************************

- annual_2D Directory containing MATLAB files of North Atlantic 2-dimensional variables (lat x lon) throughout the 16 UKESM experiments.

Variables: 

- mixed layer depth "mlotst" [m] calculated as the depth at which density exceeds the density at 10 m + 0.03 kg m-3

- surface dissolved inorganic nitrate "DIN" [mmol N m-3]

- surface chlorophyll-a concentration in both non-diatoms and diatoms combined "CHNCHD" [mg Chl m-3]

- sea surface height "zos" [m] (pre-industrial only)

Experiments: 

- pre-industrial "pi"

- historical "historical"

- positive emissions "rampup"

- zero emissions from 1.5, 2, 2.5, 3, 4, 5 and 6 degreec C global warming levels "zeroX"

- slow negative emissions from 1.5, 2, 3, 4, 5 and 6 degreec C global warming levels "snegX"

For each variable (e.g. DIN.mat for the rampup experiment), the MATLAB file contains:

- t: time (years). 

    The rampup, zeroX and snegX all have the year 1850 as the start of the rampup

The pre-industrial has shifted years as the year 2227 is when the rampup branched off (i.e. year 1850 of the rampup, zeroX and snegX)

The historical aligns to real years.

- lon: longitude

- lat: latitude

- annual_max: the maximum of the monthly means

- annual_min: the minimum of the monthly means (provided for SSH/zos.mat only)

- regional_means Regional means of the annual_2D data, for both the global "Global" regional means and the SPG "SSH_contour" regional means of various variables.

- regional_means_3D Regional means of the annual 3D data, for the SPG "SSH_contour" regional means of various variables.

- regions Model grid mask for the selected SPG region

- time2recovery Mean trends averaged over the SPG region and calculated time to recovery for each experiment, using method 1 of trend calculation

Duplicate folder time2recovery_method2 provides the same but using method 2 for trend calculation.

- allMeanTrends Mean trends calculated for each grid cell within the SPG region, for each experiment, using method 1 of trend calculation

Duplicate folder allMeanTrends_method2 provides the same but using method 2 for trend calculation.

 

Plots subfolders *************************************************************************************

- Figure1 Figure 1

- validation Figure 2

- trends/maps Panels required for Figures 3, 5, 6, S6, S7, using method 1 of trend calculation.

- composite_results Figure panels for Figure 4

- maps Plots like Figures 7, S8, S9, S11

- hovmoller Figure 8

- hysteresis Plots like Figure 9

- pi Figure S1

- EarlyWarning Figure S2

- trends/SSH_contour Figures S3, S4, S5 and tabulated data for Table 1, using method 1 of trend calculation.

- trends_method2/SSH_contour Tabulated data for Table S1, using method 1 of trend calculation.