Data source

1. Data of specific occurrence locations of marine species

Raw data sources: OBIS, https://obis.org/data/access/

2. Data of the concentration of marine chlorophyll-a in the Northern Hemisphere from 1993 to 2020

Raw data sources: Copernicus Marine Service, https://marine.copernicus.eu/

Data preprocessing

Files	Remarks
Diet_research_example.pdf	Show how to query the diet of marine families from online databases.
extract_occurrence.py	Extract the occurrence locations of marine species from the raw data (obis_20221006.csv) and save the output to a file named data_Occurrence.csv.
extract_Latitude_data.py	Extract the latitude positions of marine families from the data_Occurrence.csv file, and save the output to a file named family_year_median_df.csv. Then, output the data for each trophic level, saving it from trophic_level 1.csv to trophic_level 5.csv."
extract_chl_data.py	Download the raw chlorophyll-a data (cmems_mod_glo_bgc_my_0.25_P1M-m) from the website, process the data, and save the output to a file named chl_data.csv.
data_processing.m	Process the data from family_year_median_df.csv and chl_data.csv, and save the output to final_merge_df_latitude.csv, DataNew.mat, and chloroph.mat. These data will be used for subsequent calculations and to generate visualizations.