Luiz-Silva Wanderson, Oscar-Júnior Antonio Carlos
Department of Meteorology, Institute of Geosciences, Federal University of Rio de Janeiro-UFRJ, Rio de Janeiro, Brazil.
Postgraduate Program in Civil Defense and Security, Fluminense Federal University-UFF, Niterói, Brazil.
Nat Hazards (Dordr). 2022;114(1):713-732. doi: 10.1007/s11069-022-05409-5. Epub 2022 Jun 6.
This paper presents a synthesis of the main characteristics of precipitation in the State of Rio de Janeiro (Brazil) based on extreme rainfall indicators. Daily precipitation data are derived from 56 rainfall stations during the second half of the twentieth century and the 2000s. Eight indices related to extreme precipitation were analyzed. The Mann-Kendall nonparametric test and the Sen's Curvature were employed to evaluate the significance and magnitude of trends. The primary climatological aspects and identified trends throughout the last decades are discussed, besides the hydrometeorological impacts associated with them. Lower values of annual total precipitation are recorded in northern Rio de Janeiro (around 800 mm) and higher in the southern State (up to 2,200 mm). The Serra do Mar affects the frequency of heavy precipitation, and the areas near the sea and high relief present the highest values of consecutive days with expressive rainfall (more than 150 mm in 5 days). These areas also showed a high concentration of flood and landslides events. Most of Rio de Janeiro exhibits precipitation intensity of about 13 mm/day. The maximum number of consecutive dry days shows a gradient from the coast (about 30 days) to the State's interior (around 50 days). Regarding trends, there is a growth of accumulated extreme precipitation in various stations near the ocean. The extreme rainfall in 24 h displays an increase in most Rio de Janeiro (+ 1 to + 5 mm/decade). The consecutive dry and rainy days present similar signs of decreasing trends, suggesting irregularly distributed precipitation in the State. This study is especially relevant for decision-makers who need detailed information in the short and long term to prevent natural hazards like floods and landslides and the related impacts in the environmental and socioeconomic sectors of the Rio de Janeiro.
本文基于极端降雨指标，综合介绍了巴西里约热内卢州降水的主要特征。日降水数据来自20世纪下半叶和21世纪头十年的56个降雨站。分析了与极端降水相关的八个指标。采用曼-肯德尔非参数检验和森氏斜率来评估趋势的显著性和幅度。除了与之相关的水文气象影响外，还讨论了过去几十年的主要气候特征和确定的趋势。里约热内卢北部年总降水量较低（约800毫米），南部较高（可达2200毫米）。马尔山脉影响强降水的频率，沿海和高海拔地区连续多日出现强降雨（5天内超过150毫米）的天数最多。这些地区洪水和山体滑坡事件也高度集中。里约热内卢大部分地区的降水强度约为13毫米/天。连续干旱天数的最大值从沿海（约30天）到该州内陆（约50天）呈梯度变化。关于趋势，海洋附近各站点的极端降水累积量有所增加。里约热内卢大部分地区24小时极端降雨量呈增加趋势（每十年增加1至5毫米）。连续干旱和降雨天数呈现出类似的下降趋势迹象，表明该州降水分布不均。这项研究对决策者尤为重要，他们需要短期和长期的详细信息，以预防洪水和山体滑坡等自然灾害以及里约热内卢环境和社会经济部门的相关影响。
