Trends in extreme rainfall over ecologically sensitive Western Ghats and coastal regions of Karnataka: an observational assessment

Rainfall is one of the pivotal climatic variables, which influence spatio-temporal patterns of water availability. In this study, we have attempted to understand the interannual long-term trend analysis of the daily rainfall events of ≥?2.5 mm and rainfall events of extreme threshold, over the Western Ghats and coastal region of Karnataka. High spatial resolution (0.25°?×?0.25°) daily gridded rainfall data set of Indian Meteorological Department was used for this study. Thirty-eight grid points in the study area was selected to analyze the daily precipitation for 113 years (1901–2013). Grid points were divided into two zones: low land (exposed to the sea and low elevated area/coastal region) and high land (interior from the sea and high elevated area/Western Ghats). The indices were selected from the list of climate change indices recommended by ETCCDI and are based on annual rainfall total (RR), yearly 1-day maximum rainfall, consecutive wet days (≥?2.5 mm), Simple Daily Intensity Index (SDII), annual frequency of very heavy rainfall (≥?100 mm), frequency of very heavy rainfall (≥?65–100 mm), moderate rainfall (≥?2.5–65 mm), frequency of medium rainfall (≥?40–65 mm), and frequency of low rainfall (≥?20–40 mm). Mann-Kendall test was applied to the nine rainfall indices, and Theil-Sen estimator perceived the nature and the magnitude of slope in rainfall indices. The results show contrasting trends in the extreme rainfall indices in low land and high land regions. The changes in daily rainfall events in the low land region primarily indicate statistically significant positive trends in the annual total rainfall, yearly 1-day maximum rainfall, SDII, frequency of very heavy rainfall, and heavy rainfall as well as medium rainfall events. Furthermore, the overall annual rainfall strongly correlated with all the rainfall indices in both regions, especially with indices that represent heavy rainfall events which is responsible for the total increase of rainfall.     

Trends and extreme value analysis of rainfall pattern over homogeneous monsoon regions of India

Trends of pre-monsoon, monsoon and post-monsoon rainfall pattern were studied on decadal basis over different homogeneous monsoon regions in India for the period 1871–2008. It is attempted to understand the relation of monsoon rainfall with the global teleconnections of El Niño and La Niña, for which the correlation analysis has been carried out with Darwin pressure and Niño 3.4 sea surface temperature (Niño 3.4 SST). The correlation analysis inferred that the significant correlations were observed when monsoon rainfall is related to ENSO indices on decadal scale than on annual ones. The study also found that the north-west region is more affected by the moderate El Niño years compared to strong El Niño years. The regions Central North-East and North-East could not make any difference among weak, moderate and strong La Niña events. The authors also have carried out the extreme value analysis over different homogeneous monsoon regions of India as well as for whole India. The results show that the return values of rainfall are increasing with the return periods for the forthcoming 10, 20, 50 and 100 years. The heterogeneity in number of threshold years that were recorded for the extreme rainfall over north-east (humid climatic type) and north-west (arid climatic type) described the climate variability. The results of the present study may be useful for the policy makers in understanding the rainfall exceedance in different return periods for planning the risk management strategies.     

近40年中国平均气候与极值气候变化的概述

随着中国气象局对近50年来逐日气象观测资料的释放,人们从不同的角度对中国平均气候和极端气候的分布特征有了更多的了解.从目前研究的结果来看,这些认识需要有一个集成,即需要有一个总体的归纳和解释.通过中国近40年来的温度极值和降水极值事件的分析认识到全球增暖和区域环流异常决定着气候极值事件的分布格局.与全球增暖相联系的是:我国微量降水在空间上表现为一致的减少趋势,我国北方寒潮事件显著减少,冷夜和冷日的减少与暖夜和暖日的增多并存,以及极端强降水有增多的趋势.与东亚季风气流和西风带气流异常对应的我国有效降水在区域分布上发生了显著变化,东部季风区中的"北涝南旱"从1970年代末转型为"南涝北旱",与华南的偏干一起形成了东部季风区降水从华南、长江到华北的"-、 、-"异常分布型,但华南在1991年出现了转湿的突变;东北和西北先后从1983年和1987年前后转为暖湿气候.极端温度和极端降水趋势的空间分布与平均温度和平均降水趋势的空间分布一致.     

Daily rainfall statistics of TRMM and CMORPH: A case for trans-boundary Gandak River basin

Satellite precipitation products offer an opportunity to evaluate extreme events (flood and drought) for areas where rainfall data are not available or rain gauge stations are sparse. In this study, daily precipitation amount and frequency of TRMM 3B42V.7 and CMORPH products have been validated against daily rain gauge precipitation for the monsoon months (June–September or JJAS) from 2005–2010 in the trans-boundary Gandak River basin. The analysis shows that the both TRMM and CMORPH can detect rain and no-rain events, but they fail to capture the intensity of rainfall.     

Analyzing rainfall seasonality and trends in the North Maharashtra region

The North Maharashtra region comprises three districts, namely Jalgaon, Dhule, and Nandurbar. The region comprises 25 talukas, which are mostly covered by agricultural fields. Seasonality and trend analysis of rainfall over North Maharashtra region from 1901 to 2016 is conducted in the present work. The data were analyzed on the basis of season, i.e. winter, pre-monsoon, monsoon, and post monsoon. For trend detection, the Sen’s slope estimator and the Mann–Kendall test are used. The largest negative rainfall trends are found in the talukas Nandurbar and Jamner. In Akkalkuwa, the strongest positive trend is found. The rainfall trends in the recent years are discussed in the present work.     

Impact of Rainfall Variability on River Hydrology: A Case Study of Southern Western Ghats,India

The Western Ghats plays a pivotal role in determining the hydrological and hydroclimatic regime of Peninsular India. The mountainous catchments of the Ghats are the primary contributors of flow in the rivers that sustains the life and agricultural productivity in the area. Although many studies have been conducted in the past decades to understand long term trends in the meteorological and hydrological variables of major river basins, not much attention have been made to unfold the relationship existing among rainfall and river hydrology of natural drainages on either side of the Western Ghats which host one of the unique biodiversity hotspots across the world. Therefore, an attempt has been made in this paper to examine the short term (last three decades) changes in the rainfall pattern and its influence on the hydrological characteristics of some of the important rivers draining the southern Western Ghats as a case study. The short term, annual and seasonal trends in the rainfall, and its variability and discharge were analyzed using Mann-Kendall test and Sen’s estimator of slope. The study showed a decreasing trend in rainfall in the southwest monsoon while a reverse trend is noticed in northeast monsoon. Correspondingly, the discharge of the west and east flowing rivers also showed a declining trend in the southwest monsoon season. The runoff coefficient also followed the trends in the discharge. The runoff coefficient of the Periyar river showed a decreasing trend, whereas the Cauvery river exhibited an increasing trend. A high-resolution analysis of rainfall data revealed that the number of moderate rainfall events showed a decreasing trend throughout the southern Western Ghats, whereas the high intensity rainfall events showed an opposite trend. The decline in groundwater level in the areas which recorded an increase in high intensity rainfall events and decrease in moderate rainfall events showed that the groundwater recharge process is significantly affected by changes in the rainfall pattern of the area.     

Trend analysis of rainfall pattern over the Central India during 1901–2010

In the present study, trends of rainfall of the Central India were evaluated in monthly, seasonal, and annual time scales using the Revised Mann-Kendall (RMK) test, Sen’s slope estimator, and innovative trend method (ITM). For this purpose, the monthly rainfall data for 20 stations in Madhya Pradesh (MP) and Chhattisgarh (CG) states in Central India during 1901–2010 was used. The Sen’s slope estimator was utilized for calculating the slope of rainfall trend line. Based on the obtained results of RMK test, there is no significant trend in the stations for the January and October months. The results also showed that for MP, two out of 15 considered stations indicate significant annual trend, while the CG has four out of five stations with significant trend. The results of applying ITM test indicated that most of the stations have decreasing trends in annual (16 stations), summer (16 stations), and monsoon (11 stations) seasons, while the winter (12 stations) and post monsoon (11 stations) seasons generally show increasing trend. Unlike the RMK, the ITM shows significant increasing trend in rainfall of November and December months. The finding of current study can be used for irrigation and water resource management purpose over the Central India.     

Adaptation of climate variability/extreme in arid environment of the Arabian peninsula by rainwater harvesting and management

Water management in Saudi Arabia is facing major challenges due to the limited water resources and increasing uncertainties caused by climate change. The rainfall and temperature records of the Saudi meteorological data for more than three decades were analyzed for policy suggestions in water sectors based on the changing rainfall patterns. The trends in the annual aridity and rain indices were also examined to define the changing climate conditions and for determining the dry months in different cities of the Kingdom. An increased annual and maximum rainfall was observed for six cities while a decreasing trend in both annual and maximum rainfall was observed for the same number of cities highlighting the variability of rainfall in the whole region. An increasing maximum rainfall with decreasing annual rainfall was observed for the rest of the cities signifying the more extreme rainfall evens and resulting floods of short durations. The changing rainfall trends were also observed for different months during 31 years of the recorded period in addition to the varying climate pattern for different cities within the same district. Finally, these preliminary assessments of any systematic changes in view of the increased rain intensities and extreme climate events are viewed to demonstrate the value rainwater harvesting and management as a local adaptation to the climate variability and extreme in the Kingdom.     

District-wide drought climatology of the southwest monsoon season over India based on standardized precipitation index (SPI)

District-wide drought climatology over India for the southwest monsoon season (June–September) has been examined using two simple drought indices; Percent of Normal Precipitation (PNP) and Standardized Precipitation Index (SPI). The season drought indices were computed using long times series (1901–2003) of southwest monsoon season rainfall data of 458 districts over the country. Identification of all India (nation-wide) drought incidences using both PNP and SPI yielded nearly similar results. However, the district-wide climatology based on PNP was biased by the aridity of the region. Whereas district-wide drought climatology based on SPI was not biased by aridity. This study shows that SPI is a better drought index than PNP for the district-wide drought monitoring over the country. SPI is also suitable for examining break and active events in the southwest monsoon rainfall over the country. The trend analysis of district-wide season (June–September) SPI series showed significant negative trends over several districts from Chattisgarh, Bihar, Kerala, Jharkhand, Assam and Meghalaya, Uttaranchal, east Madhya Pradesh, Vidarbha etc., Whereas significant positive trends in the SPI series were observed over several districts from west Uttar Pradesh, west Madhya Pradesh, South & north Interior Karnataka, Konkan and Goa, Madhya Maharashtra, Tamil Nadu, East Uttar Pradesh, Punjab, Gujarat etc.     

Numerical simulation of cloud burst event on August 05, 2010, over Leh using WRF mesoscale model

Localized deep cumulus convective clouds have a capability of giving enormous amount of rainfall over a limited horizontal area, within a short span of time. Such types of extreme rainfall events are most common over the high elevated areas of Northern India during the Southwest monsoon season which causes widespread damage to the property and lives. Therefore, it is necessary to predict such extreme events accurately to avoid damage associated with them. The numerical mesoscale model Weather Research and Forecasting has been used to simulate the cloud burst event of Leh on August 05, 2010, so as to capture the main characteristics of the various parameters associated with this localized mesoscale phenomenon. The model has been integrated with four nested domains keeping Leh and its adjoining area as center. Two cloud microphysics parameterization schemes namely WSM3 and WSM6 have been used for the sensitivity experiments and results have been analyzed to examine the performance of both the schemes in capturing such extreme localized heavy rainfall events. Results show that the WSM6 microphysics was able to simulate the precipitation near to the observation. WSM3 microphysics simulated the location of the circulation near to the observation. In addition, the results also show that the maximum magnitudes of meridional and vertical wind as simulated with WSM3 microphysics are 12 and 4 m/s, respectively.     

Factors triggering landslide occurrence on the Zemun loess plateau,Belgrade area,Serbia

Among the numerous factors that trigger landslide events, the anthropogenic impact caused by inadequate planning and faulty land use in urban areas is increasing. The Zemun settlement on the northern outskirts of Belgrade has experienced a number of landslides in the last three decades, endangering buildings and roads, and claiming human lives, particularly in the case of the 2010/2011 landslides. Selected meteorological parameters were used to calculate rainfall erosivity indices such as Precipitation Concentration Index and Modified Fournier Index over the period 1991–2015. Drought indices, Lang aridity index and Palfai Drought Index were calculated as well. Mann–Kendall trend test was applied to identify potential rising and/or declining trends both in meteorological parameters and calculated indices. Trend analysis of the annual and seasonal scales yielded a statistically significant trend in the spring time series. Stable arid and pronounced drought conditions were recorded. The modified Fournier index based on monthly mean values yields moderate aggressiveness, with several extreme values indicating very high erosivity classes, especially for 2010/2011. The geological substrate is predominantly loess and hence highly susceptible to erosion and slope failure when climatological conditions are suitable. Accelerated urbanization at the end of the last century reduced vegetation cover, intensified pressure on the vertical loess slope, and lacked suitable rain drainage systems so that surface-water runoff was directed into the porous loess, thereby endangering slope stability. We proposed a geomorphic model to describe the nature of the erosional processes on the loess cliffs of the Zemun loess plateau. Results from this study have implications for mitigation strategies.     

Influence of southern oscillation and SSTs over Nino-3.4 region on the winter monsoon rainfall over coastal Andhra Pradesh

An analysis of the mean monthly data of 124 years reveals that the relationship between the Southern Oscillation Index in September and the winter monsoon rainfall (WMR) over Coastal Andhra Pradesh (CAP) is variable and non-stationary. In the recent four decades, however, SOI (Sept) is negatively and significantly correlated with CAP WMR. A similar analysis is performed using 50 years of mean monthly SSTs over Nino-3.4 region in August and September and CAP WMR to detect a possible relationship and there is a striking positive relation between them. In both of the above cases, the September signal is more significant in the recent four decades than for the other months and seasons for probable prediction of CAP WMR. Finally, to examine the influence of SO on the winter monsoon rainfall, a non-parametric test “Mann-Whitney Rank Statistics” test has been applied to the rainfall associated with extreme positive and negative SOI events     

1961-2012年辽宁省极端气温事件气候变化特征

利用辽宁省52个气象台站逐日平均气温、 最高气温和最低气温数据, 使用国际通用的10种极端气候指数, 研究了1961-2012年辽宁省极端气温事件的气候变化特征. 结果表明: 年平均极端气温事件空间分布存在明显的地区差异. 时间尺度上, 1961-2012年辽宁省年及四季极端暖事件(暖昼日数、 暖夜日数、 夏季日数、 热带夜数和热浪持续指数)呈增加趋势, 极端冷事件(冷昼日数、 冷夜日数、 结冰日数、 霜冻日数和寒潮持续指数)呈减少趋势; 极端暖事件在20世纪90年代中期开始明显增加, 极端冷事件在20世纪80年代末期开始显著减少; 极端暖事件的变化速率要小于极端冷事件. 辽宁省气温日较差有增大的趋势, 极端暖(冷)事件的增加(减少)在秋季(冬季)最为显著. 空间变化上, 极端气温事件在全省基本都呈一致的增加或减少的分布. 多数极端气温事件均存在8 a左右的周期, 检测到的突变的时间大致在20世纪80年代中期到90年代末期. 20世纪80年代末期辽宁省气候变暖后, 极端暖事件和冷事件均有明显的增加和减少.     

The influence of groundwater abstraction on interpreting climate controls and extreme recharge events from well hydrographs in semi-arid South Africa

There is a scarcity of long-term groundwater hydrographs from sub-Saharan Africa to investigate groundwater sustainability, processes and controls. This paper presents an analysis of 21 hydrographs from semi-arid South Africa. Hydrographs from 1980 to 2000 were converted to standardised groundwater level indices and rationalised into four types (C1–C4) using hierarchical cluster analysis. Mean hydrographs for each type were cross-correlated with standardised precipitation and streamflow indices. Relationships with the El Niño–Southern Oscillation (ENSO) were also investigated. The four hydrograph types show a transition of autocorrelation over increasing timescales and increasingly subdued responses to rainfall. Type C1 strongly relates to rainfall, responding in most years, whereas C4 notably responds to only a single extreme event in 2000 and has limited relationship with rainfall. Types C2, C3 and C4 have stronger statistical relationships with standardised streamflow than standardised rainfall. C3 and C4 changes are significantly (p <?0.05) correlated to the mean wet season ENSO anomaly, indicating a tendency for substantial or minimal recharge to occur during extreme negative and positive ENSO years, respectively. The range of different hydrograph types, sometimes within only a few kilometres of each other, appears to be a result of abstraction interference and cannot be confidently attributed to variations in climate or hydrogeological setting. It is possible that high groundwater abstraction near C3/C4 sites masks frequent small-scale recharge events observed at C1/C2 sites, resulting in extreme events associated with negative ENSO years being more visible in the time series.

     

Indonesian rainfall variability during Western North Pacific and Australian monsoon phase related to convectively coupled equatorial waves

The Indonesian archipelago which has over 15,000 islands, lies in the tropics between Asia and Australia. This eventually alters the rainfall variability over the region, which was influenced by the Asian-Australian monsoon and controlled by intraseasonal variabilities such as convectively coupled equatorial waves (CCEW), i.e., Kelvin, n?=?1 equatorial Rossby (ER), mixed Rossby gravity (MRG), and n?=?1 Westward inertio gravity (WIG), including the Madden–Julian Oscillation (MJO). This study examines a 15-year 3B42 data for trapping CCEW and MJO in the region of Indonesia during both active and extreme Western North Pacific (WNP) and Australian (AU) monsoon phases, which are then compared with 30-year rainfall anomalies among 38 synoptic stations over Indonesia. The space–time spectral analysis is employed to filter each wave including the MJO in the equator, then proceeding with the empirical orthogonal function (EOF) method to seek each wave peak which then coincides with WNP and AU monsoon peaks over Indonesia. It is concluded that an extreme monsoon classification has proven to control rainfall activity related to the CCEW and MJO at 60.66% during December through February (DJF)-WNP for only the significant wave perturbation value. Meanwhile, the CCEW and MJO significantly increase/decrease precipitation at Day 0 for about 37.88% from the total of Day 1st to Day end. Although the contribution of the CCEW and MJO does not profoundly influence rainfall activity during monsoon phase over Indonesia, they still modulate weather condition for more than 50%. On the other hand, a complex topography with a number of land–sea complexities is capable of influencing the rainfall variability in the region as a negative relationship is associated with the CCEW and MJO either during DJF-WNP or July through August (JAS)-AU monsoon phase.     

Simulation of high-impact tropical weather events: comparative analysis of three heavy rainfall events

Episodes of heavy rainfall, although relatively rare, significantly contribute to the hydrological cycle due to the large quantum of rainfall in a short span of time. Accurate simulation of such heavy or extreme rainfall events therefore is an important benchmark for a model. Here, we consider the simulation of three heavy rainfall events (Mumbai, Bangalore and Chennai) that occurred over the Indian monsoon region in different geographical locations and seasons during 2005, using a mesoscale meteorological model, namely MM5V3. Simulations have been carried out at high resolution (2 km) to resolve orographic features and land–ocean gradients over the event locations with a 3-nest, 2-way configuration. The primary objective of this study is to carry out a multi-event, multi-location evaluation of the model configuration for simulating a class of heavy rainfall events and to compare some important meteorological features of the events. Our results have shown that a very high relative humidity, low-level convergence, convective instability in terms of equivalent potential temperature, high vertical velocity, smaller mixing ratio at low level and higher mixing ratio at upper level essentially dominated and sustained the convective dynamics in all the three events. It was also found that the latent heat flux (LHF) dominated coastal events (Mumbai and Chennai) with relatively much higher values compared to sensible heat flux (SHF) throughout the event life cycle. In the case of the Bangalore event, both LHF and SHF are comparable during the event life cycle.     

Variations in water clarity and chlorophylla in Tampa Bay, Florida, in response to annual rainfall, 1985–2004

In the Tampa Bay region of Florida, extreme levels of annual and seasonal rainfall are often associated with tropical cyclones and strong El Niño episodes. We used stepwise multiple regression models to describe associations between annual and seasonal rainfall levels and annual, bay-segment mean water clarity (as Secchi depth [m]), chlorophylla (μg I^?1), color (pcu), and turbidity (ntu) over a 20-yr period (1985–2004) during which estimated nutrient loadings have been dominated by non-point sources. For most bay segments, variations in annual mean water clarity were associated with variations in chlorophylla concentrations, which were associated in turn with annual or seasonal rainfall. In two bay segments these associations with annual rainfall were superimposed on significant long-term declining trends in chlorophylla. Color was significantly associated with annual rainfall in all bay segments, and in one segment variations in color were the best predictors of variations in water clarity. Turbidity showed a declining trend over time in all bay segments and no association with annual rainfall, and was significantly associated with variations in water clarity in only one bay segment. While chlorophylla, color, and turbidity a affected water clarity to varying degrees, the effects of extreme rainfall events (El Niño events in 1998 and 2003, and multiple tropical cyclone events in 2004) on water clarity were relatively short-lived, persisting for periods of months rather than years. During the 20-yr period addressed in these analyses, declining temporal trends in chlorophylla and turbidity, produced in part by a long-term watershed management program that has focused on curtailing annual loadings of nitrogen and other pollutants, may have helped to prevent the bay as a whole from responding more adversely to the high rainfall periods that occurred in 1998 and 2003–2004.     

Identification of trends in rainfall,rainy days and 24 h maximum rainfall over subtropical Assam in Northeast India

Trends in rainfall, rainy days and 24 h maximum rainfall are investigated using the Mann-Kendall non-parametric test at twenty-four sites of subtropical Assam located in the northeastern region of India. The trends are statistically confirmed by both the parametric and non-parametric methods and the magnitudes of significant trends are obtained through the linear regression test. In Assam, the average monsoon rainfall (rainy days) during the monsoon months of June to September is about 1606 mm (70), which accounts for about 70% (64%) of the annual rainfall (rainy days). On monthly time scales, sixteen and seventeen sites (twenty-one sites each) witnessed decreasing trends in the total rainfall (rainy days), out of which one and three trends (seven trends each) were found to be statistically significant in June and July, respectively. On the other hand, seventeen sites witnessed increasing trends in rainfall in the month of September, but none were statistically significant. In December (February), eighteen (twenty-two) sites witnessed decreasing (increasing) trends in total rainfall, out of which five (three) trends were statistically significant. For the rainy days during the months of November to January, twenty-two or more sites witnessed decreasing trends in Assam, but for nine (November), twelve (January) and eighteen (December) sites, these trends were statistically significant. These observed changes in rainfall, although most time series are not convincing as they show predominantly no significance, along with the well-reported climatic warming in monsoon and post-monsoon seasons may have implications for human health and water resources management over bio-diversity rich Northeast India.     

Analysis of seasonal and annual rainfall trends for Ranchi district,Jharkhand, India

The aim of this study was to investigate temporal variation in seasonal and annual rainfall trend over Ranchi district of Jharkhand, India for the period (1901–2014: 113 years). Mean monthly rainfall data series were used to determine the significance and magnitude of the trend using non-parametric Mann–Kendall and Sen’s slope estimator. The analysis showed a significant decreased in rainfall during annual, winter and southwest monsoon rainfall while increased in pre-monsoon and post-monsoon rainfall over the Ranchi district. A positive trend is detected in pre-monsoon and post-monsoon rainfall data series while annual, winter and southwest monsoon rainfall showed a negative trend. The maximum decrease in rainfall was found for monsoon (? 1.348 mm year^?1) and minimum (? 0.098 mm year^?1) during winter rainfall. The trend of post-monsoon rainfall was found upward (0.068 mm year^?1). The positive and negative trends of annual and seasonal rainfall were found statistically non-significant except monsoon rainfall at 5% level of significance. Rainfall variability pattern was calculated using coefficient of variation CV, %. Post-monsoon rainfall showed the maximum value of CV (70.80%), whereas annual rainfall exhibited the minimum value of CV (17.09%), respectively. In general, high variation of CV was found which showed that the entire region is very vulnerable to droughts and floods.     

Climate extremes related with rainfall in the State of Rio de Janeiro,Brazil: a review of climatological characteristics and recorded trends

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.