Supplementary Data for "Cause-and-effect relationships between sea surface temperature changes in different regions during the past 4.5 million years"

This archive stores the data, results, and numerical codes for reproducing results in "Cause-and-effect relationships between sea surface temperature changes in different regions during the past 4.5 million years" by T. Alberti, M. Stumpo, F. Florindo, E.J. Rohling. Detailed information on files and their content can be found below. 1) sst_data.txt contains the raw data extrapolated from Clark et al., Global and regional temperature change over the past 4.5 million years. Science, 383 (6685), 884–890 (2024). The first column is the time in Myr BP, while columns 2-18 report the sea surface temperature (SST) data for each region: Northern Hemisphere, Southern Hemisphere, NH Extratropics, SH Extratropics, Tropics, Indo-Pacific Warm Pool (IPWP), Eastern Tropical Pacific (ETP), Subtrop upwelling, Eq upwelling, Warm pool, North Atlantic (Natl), Tropical Atlantic (tropAtl), South Atlantic (Satl), North Pacific (Npac), South Pacific (Spac), Tropical Pacific (tropPac). 2) Files IMF_##.txt contain the multivariate Intrinsic Mode Functions extracted from time series of SST reported in sst_data.txt. IMFs are ordered in terms of increasing timescales (i.e., 1 - lowest timescale, 13 - highest timescale). To extract IMFs we used the freely available numerical code for Matlab provided at https://www.commsp.ee.ic.ac.uk/~mandic/research/emd.htm by N. Rehman and D. P. Mandic, Multivariate Empirical Mode Decomposition, Proceedings of the Royal Society A, vol. 466, no. 2117, pp. 1291-1302, 2010. 3) LRT.py contains the Python source code to perform Linear Response (LR) analysis among the different regions of SSTs and for the different IMFs. 4) analysis_emd.py contains the Python source code to produce the response matrix at a particular lag time. 5) LR_SST_results.json contains the results of the Linear Response (LR) analysis among the different regions of SSTs and for the different IMFs. 6) Figure_paper.m is a Matlab code to reproduce the figures of the paper. 7) Figure_LR.m is a Matlab code to reproduce Figure 5 of the paper.