Brazil experiences extreme weather and climate events that cause numerous economic and social losses, and according to climate change projections, these events will increase in intensity and frequency over this century.This study adds to the body of research on Brazil’s climate change by analyzing the historical patterns and projected changes in temperature and precipitation extremes across Brazil using the World Climate Research Program’s Expert Team on Climate Change Detection and Indices framework. This novel approach analyzes climate extreme events over the past four decades (1980–2016) using multiple gridded observation and reanalysis datasets. Furthermore, future changes in climate extremes are analyzed from 20 downscaled Earth System Models (ESMs) at high horizontal resolution (0.25° of latitude/longitude), under two representative concentration pathway scenarios (RCP4.5 and RCP8.5). Projected changes in the extreme indices are analyzed over mid-twenty-first century (2046–2065) and end-of-twenty-first century (2081–2100) relative to the reference period 1986–2005. Results show consistent warming patterns with increasing (decreasing) trends in warm (cold) extremes in the historical datasets. A similar but more intense warm pattern is projected in the mid and end of the twenty-first century. For precipitation indices, observations show an increase in consecutive dry days and a reduction of consecutive wet days over almost all Brazil. The frequency and intensity of extremely wet days over Brazil are expected to increase according to future scenarios. Designing effective adaptation and mitigation measures in response to changes in climate extremes events depends on this improved understanding of how conditions have and are likely to change in the future at regional scales.

巴西经历了极端天气和气候事件，造成了巨大的经济和社会损失，根据气候变化的预测，这些事件在本世纪的强度和频率将增加。通过分析历史，本研究增加了对巴西气候变化的研究使用世界气候研究计划的气候变化检测和指数专家团队，研究整个巴西的温度和降水极端变化的模式和预测变化。这种新颖的方法使用多个网格化的观测和再分析数据集来分析过去四个十年（1980-2016年）的气候极端事件。此外，我们还以20种按比例缩小的地球系统模型（ESM）在高水平分辨率（纬度/经度0.25°）下分析了极端气候的未来变化，在两个代表性的集中途径情景下（RCP4.5和RCP8.5）。相对于参考时期1986-2005，分析了极端指数的预计变化，其范围在二十一世纪中叶（2046-2065）和二十一世纪末（2081-2100）。结果显示，历史数据集中的暖化模式具有一致的增暖模式，且极端（寒冷）极端情况具有增加（减少）趋势。在二十一世纪中叶和二十世纪末，预计将出现类似但更为强烈的温暖模式。对于降水指数，观测表明几乎在整个巴西，连续的干旱天增加，而连续的湿天减少。根据未来的情况，预计巴西全天极端潮湿的天气的频率和强度都会增加。