Impact of temperature and precipitation extremes on the flowering dates of four German wildlife shrub species
Jonatan F. Siegmund1,2,Marc Wiedermann1,3,Jonathan F. Donges4,5,and Reik V. Donner1Jonatan F. Siegmund et al.Jonatan F. Siegmund1,2,Marc Wiedermann1,3,Jonathan F. Donges4,5,and Reik V. Donner1
Received: 13 Sep 2015 – Discussion started: 16 Nov 2015 – Revised: 25 Aug 2016 – Accepted: 20 Sep 2016 – Published: 06 Oct 2016
Abstract. Ongoing climate change is known to cause an increase in the frequency and amplitude of local temperature and precipitation extremes in many regions of the Earth. While gradual changes in the climatological conditions have already been shown to strongly influence plant flowering dates, the question arises if and how extremes specifically impact the timing of this important phenological phase. Studying this question calls for the application of statistical methods that are tailored to the specific properties of event time series. Here, we employ event coincidence analysis, a novel statistical tool that allows assessing whether or not two types of events exhibit similar sequences of occurrences in order to systematically quantify simultaneities between meteorological extremes and the timing of the flowering of four shrub species across Germany. Our study confirms previous findings of experimental studies by highlighting the impact of early spring temperatures on the flowering of the investigated plants. However, previous studies solely based on correlation analysis do not allow deriving explicit estimates of the strength of such interdependencies without further assumptions, a gap that is closed by our analysis. In addition to direct impacts of extremely warm and cold spring temperatures, our analysis reveals statistically significant indications of an influence of temperature extremes in the autumn preceding the flowering.
In this study we systematically quantify simultaneities between meteorological extremes and the timing of flowering of four shrub species across Germany by using event coincidence analysis. Our study confirms previous findings of experimental studies, highlighting the impact of early spring temperatures on the flowering of the investigated plants. Additionally, the analysis reveals statistically significant indications of an influence of temperature extremes in the fall preceding the flowering.
In this study we systematically quantify simultaneities between meteorological extremes and the...