University of Lisbon Researchers Publish New Data on Earth Science (Probabilistic modelling of the dependence between rainfed crops and drought hazard)

Insurance Daily News

2019 DEC 23 (NewsRx) -- By a News Reporter-Staff News Editor at Insurance Daily News -- Investigators publish new report on earth science. According to news reporting originating from Lisbon, Portugal, by NewsRx correspondents, research stated, “Extreme weather events, such as droughts, have been increasingly affecting the agricultural sector, causing several socio-economic consequences. The growing economy requires improved assessments of drought-related impacts in agriculture, particularly under a climate that is getting drier and warmer.”

The news reporters obtained a quote from the research from University of Lisbon: “This work proposes a probabilistic model that is intended to contribute to the agricultural drought risk management in rainfed cropping systems. Our methodology is based on a bivariate copula approach using elliptical and Archimedean copulas, the application of which is quite recent in agrometeorological studies. In this work we use copulas to model joint probability distributions describing the amount of dependence between drought conditions and crop yield anomalies. Afterwards, we use the established copula models to simulate pairs of yield anomalies and drought hazard, preserving their dependence structure to further estimate the probability of crop loss. In the first step, we analyse the probability of crop loss without distinguishing the class of drought, and in the second step we compare the probability of crop loss under drought and non-drought conditions. The results indicate that, in general, Archimedean copulas provide the best statistical fits of the joint probability distributions, suggesting a dependence among extreme values of rainfed cereal yield anomalies and drought indicators.”

According to the news editors, the research concluded: “Moreover, the estimated conditional probabilities suggest that when drought conditions are below moderate thresholds, the risk of crop loss increases between 32.53 % (cluster 1) and 32.6 % (cluster 2) in the case of wheat and between 31.63 % (cluster 2) and 55.55 % (cluster 2) in the case of barley. From an operational point of view, the results aim to contribute to the decision-making process in agricultural practices.”

For more information on this research see: Probabilistic modelling of the dependence between rainfed crops and drought hazard. Natural Hazards and Earth System Sciences, 2019,19():2795-2809. (Natural Hazards and Earth System Sciences - http://www.nat-hazards-earth-syst-sci.net/volumes_and_issues.html). The publisher for Natural Hazards and Earth System Sciences is Copernicus Publications.

A free version of this journal article is available at https://doi.org/10.5194/nhess-19-2795-2019.

Our news journalists report that more information may be obtained by contacting A. F. S. Ribeiro, Instituto Dom Luiz (IDL), Faculdade de Ciencias, University of Lisbon, 1749-016 Lisbon, Portugal. Additional authors for this research include A. Russo, C. M. Gouveia, P. Pascoa, C. A. L. Pires.