Trend Pattern of Heavy and Intense Rainfall Events in Colombia from 1981–2018: A Trend-EOF Approach

Wilmar L Cerón,Camilo Ocampo-Marulanda,Mary T Kayano,Teresita Canchala,Alvaro Avila-Diaz,Rita V Andreoli,Jean Antunes

doi:10.3390/atmos13020156

Abstract

The Andes mountain range divides Colombia into various climatic regions over the country, as the Andean, Caribbean, Pacific, Amazon, and Orinoco regions. Given this scenario, knowing the current change in total precipitation and their extremes values are relevant. In this study, the main goal is to assess the spatio-temporal trends of heavy and intense rainfall at a seasonal scale during the last 38 years (1981–2018) using the trend empirical orthogonal function (TEOF). An increase in maximum precipitation during five consecutive days (RX5day), Simple daily intensity index (SDII), and the number of days with precipitation above 20 mm (R20mm) and 30 mm (R30mm) during December–February and March–May was observed in most of the Colombian territory, except for the Amazon region for RX5day. A decrease in total rainfall in June–August was observed in the Andean, the Caribbean, and southern Pacific regions, while, in the northern Pacific, it increased, consistent with the trend patterns of RX5day, SDII, and R20mm. During September–November, there was a reduction in rainfall in the Amazon region and the South Pacific, and an increase in RX5day, SDII, R20mm, and R30mm in the Andean, the Caribbean, and North Pacific regions. The TEOF showed more pronounced spatial trend patterns than those obtained with the traditional Mann–Kendall test. The findings offer a better understanding of the climate extremes impacts in tropical latitudes and help planners to implement measures against the future effects of climate change.

Highlights

Seasonal trend patterns are derived from the extreme rainfall indices (Table 1), and total rainfall from Climate Hazards Group Infrared Precipitation with Stations (CHIRPS) through the trend empirical orthogonal function (TEOF) analysis, explained in the previous section
The spatial patterns of the first dominant trend mode are shown in Figure 3, while the trend principal components (TPCs) time series are in Figures 4–8 for PRP, RX5day, Simple daily intensity index (SDII), R20mm, and R30mm
The TEOF spatial pattern (Figure 3a–d) and its associated TPC1 (Figure 4) for the seasonal total precipitation represent an increase in rainfall in the first half of the year throughout Colombia, especially towards the Orinoco and the Caribbean (Figure 3a,b), with an explained variance of 4.7% and 6.9% for DJF and MAM, respectively

Summary

Introduction

The increase in the frequency, magnitude, and duration of extreme precipitation events due to climate change negatively affects the environment, ecosystems, the economy, and society’s quality of life [2,3,4,5]. In this regard, the last global risk report performed by the World Economic Forum indicates that among the highest likelihood risks of the ten years are extreme weather with relevant negative impacts, such as loss of human life, damage to ecosystems, destruction of property, and financial loss, at a global scale [6,7]

Methods

Results

Conclusion