Annals of Applied Statistics

Fire seasonality identification with multimodality tests

Jose Ameijeiras-Alonso, Akli Benali, Rosa M. Crujeiras, Alberto Rodríguez-Casal, and José M. C. Pereira

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Understanding the role of vegetation fires in the Earth system is an important environmental problem. Although fire occurrence is influenced by natural factors, human activity related to land use and management has altered the temporal patterns of fire in several regions of the world. Hence, for a better insight into fires regimes it is of special interest to analyze where human activity has altered fire seasonality. For doing so, multimodality tests are a useful tool for determining the number of annual fire peaks. The periodicity of fires and their complex distributional features motivate the use of nonparametric circular statistics. The unsatisfactory performance of previous circular nonparametric proposals for testing multimodality justifies the introduction of a new approach, considering an adapted version of the excess mass statistic, jointly with a bootstrap calibration algorithm. A systematic application of the test on the Russia–Kazakhstan area is presented in order to determine how many fire peaks can be identified in this region. A False Discovery Rate correction, accounting for the spatial dependence of the data, is also required.

Article information

Ann. Appl. Stat., Volume 13, Number 4 (2019), 2120-2139.

Received: October 2018
Revised: May 2019
First available in Project Euclid: 28 November 2019

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Zentralblatt MATH identifier

Circular data multimodality multiple testing wildfires


Ameijeiras-Alonso, Jose; Benali, Akli; Crujeiras, Rosa M.; Rodríguez-Casal, Alberto; Pereira, José M. C. Fire seasonality identification with multimodality tests. Ann. Appl. Stat. 13 (2019), no. 4, 2120--2139. doi:10.1214/19-AOAS1273.

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Supplemental materials

  • Supplementary material of fire seasonality identification with multimodality test. This Supplementary Material provides details on the models employed in the simulation study; a complete description of the calibration function used to generate the resamples in the bootstrap procedure with some theoretical background; some further simulation results showing rejection rates for different scenarios; and the construction of the land cover patches cells where a similar fire behavior is expected.