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Explora: Environment
            and Resource                                                         Statistical analysis of climate time series



            the occurrence of these events. This likely explains why, for   the studied climatic data. When fully implemented,
            both layers, we observe a fairly balanced mix of monthly   the  signals  obtained  provide  valuable  information,
            Markov-0 binomial type signals and Markov-1 lengthening   enabling precise identification of the mechanisms and
            type signals.                                      interactions at play.
              Thus, the fact that the signal may vary depending on   While this method does not reveal everything or decode
            the period considered (month, quarter, half-year, year) not   all the climatic parameters at stake, MAL undoubtedly
            only avoids real contradictions but also is well-explained   serves as a valuable additional tool for enhancing our
            and, in fact, contributes to a better understanding of the   understanding of the climate and achieving more reliable
            mechanisms at play.                                long-term projections.

            4.3. The main reason for the effectiveness of MAL    The  examples  described in  this clearly demonstrate
                                                               the value of the method, yielding results of significant
            The effectiveness of MAL lies primarily in its comparison   importance in climatology, such as:
            of two “spectra”—the spectra of 0 and 1 for each of the two   •   Detecting and explaining a phenomenon of “natural
            series being analyzed. Unlike other techniques, which rely   nervousness,” where global average temperature
            on raw initial data or, in some cases, derived data (e.g.,   differences have a greater tendency to reverse their
            differences of successive terms for deseasonalization),   sign than maintain it from 1 month to the next. 24
            MAL focuses solely on the binary aspect of whether the   •   Demonstrating, in what seems a definitive way, that
            data increase or decrease. This transition from raw data   cloudiness provides clearly negative feedback on
            to their “spectrum” leads to a huge loss of information,   global warming, with the OC acting as a natural
            retaining only this critical piece: the direction of change.   thermostat of the climate. 25
            However, by isolating this single piece of information, MAL   •   Establishing that the parameters most critical to
            prevents it from being overshadowed by other elements in   defining the global climate exhibit limited long-term
            the raw data, enabling it to detect signals and interactions   growth,  predicting  temperature  increases  by  2100
            that other statistical techniques do not detect.      significantly lower than current IPCC projections. 26

            4.4. Possible use of MAL in sectors other than       Moreover, nothing a priori prevents MAL from being
            climatology                                        applied in other sectors beyond climatology, as long as the
                                                               system is complex and time series data are available.
            Time series have long concerned many sectors other than
            climatology, including econometrics, information theory,   Acknowledgments
            demography, astronomy, and epidemiology. 2-5,46-49
                                                               None.
              Similar to its application in climatology, MAL can be
            effective in other fields, provided the digital data studied   Funding
            meet the necessary conditions for MAL processing,   None.
            particularly that their successive deviations have the same
            probability of being positive or negative. Additionally, the   Conflict of interest
            field must be complex enough to exhibit multiple and varied
            interactions, a scenario where the method is well-suited   The author declares no conflicts of interest.
            for identifying potential interactions, as demonstrated in   Author contributions
            climatology. However, these conditions are restrictive, and
            only practical experiments can determine whether MAL   This is a single-authored article.
            proves valuable outside climatology.
                                                               Ethics approval and consent to participate
              It is worth noting that the concept of using Markov
            chains to analyze time series data is not new; for instance,   Not applicable.
            it was employed as early as 1966 by Lortet-Zuckermann  to   Consent for publication
                                                        3
            analyze a series of 444 successive explosions of the star SS
            Cygni observed from 1896 to 1957.                  Not applicable.

            5. Conclusion                                      Availability of data
            MAL is a new method for analyzing climatic time    Data are available from the corresponding author upon
            series based on the length of rise or fall chains in   reasonable request.



            Volume 2 Issue 1 (2025)                         11                               doi: 10.36922/eer.6109
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