Networks analysis of Brazilian climate data based on the DCCA cross-correlation coefficient

form boxes of sizes n = 13 (one day of observations), n = 1261 (97 days of observations), and n = 3328 (256 days of observations). Fig 7 shows the network analysis for solar radiation. Regardless of the box size (13, 1261, and 3328), we see subgroups of networks interconnected mostly by nearby regions. For n = 13, the only interconnected network subgroup shows a link between seven Northeast capitals, two Central-West capitals, and one Southeast capital. When considering n = 1261, this sub-net- work also includes the three Southeast capitals that border the Atlantic Ocean and the three South capitals that also border the ocean. For n = 3328 some of the Northeast capitals closer to the equator are removed from the sub-network. Fig 8 shows the network analysis for the air temperature. When analyzing the box size n = 13, we see a strong cross-correlation, however, fragmented into three subgroups of net- works, the first represented by the capitals of Rio Grande do Norte, Ceara´, Maranhão and Para´, from the North and Northeast regions; the second formed by the capitals of Alagoas, Per- nambuco, and Paraı´ba, in the Northeast; and the third by the capitals of Minas Gerais, Tocan- tins, Goia´s, Federal District, Piauı´, Amapa´, Roraima, Rondoˆnia, Acre, Mato Grosso, and Mato Grosso do Sul. For n = 1261, three subgroups are also formed: (i) the capitals of Mato Grosso and Mato Grosso do Sul, with hot and humid climates; (ii) the capitals of the Northeast states of Bahia, Sergipe, Pernambuco, Rio Grande do Norte, Alagoas and Paraı´ba, all of them borter-

ing the Atlantic Ocean; and the capitals of Rio Grande do Sul, Santa Catarina, Parana´, São Paulo, Rio de Janeiro, Espı´rito Santo, Minas Gerais, Distrito Federal and Goia´s, states located in a close geographic location between the South, Southeast and Central-West regions. For n = 3328, two subgroups are formed, the first by the capital of Goia´s and the Distrito Federal, Fig 4. Cross-correlation, ρDCCA(n), for global radiation in the Central-West region of Brazil. The plots show the cross-correlations between the state capital written in the plot and all others in the region. https://doi.org/10.1371/journal.pone.0290838.g004 PLOS ONE Networks analysis of Brazilian climate data based on the DCCA cross-correlation coefficient PLOS ONE | https://doi.org/10.1371/journal.pone.0290838 September 15, 2023 11 / 18