CLIMATOLOGY OF EXTREME RAINFALL EVENTS IN EASTERN AND NORTHERN SANTA CATARINA STATE, BRAZIL: PRESENT AND FUTURE CLIMATE

ABSTRACT. The eastern region of Santa Catarina State (Brazil) has an important history of natural disasters due to extreme rainfall events. Floods and landslides are enhancedby local features such as orography and urbanization: the replacement of natural surface coverage causing more surface runoff and, hence, ﬂooding. Thus, studies of this type of events – which directly inﬂuence life in the towns – take on increasing importance. This work makes a quantitative analysis of occurrences of extreme rainfall events in the eastern and northern regions of Santa Catarina State in the last 60 years, through individual analysis, considering the history of ﬂoods ineach selected town, as well as an estimate through to the end of century following regional climate modeling. A positive linear trend, in most of the towns studied, was observed in the results, indicating greater frequency of these events in recent decades, and the HadRM3P climate model shows a heterogeneous increase of events for all towns in the period from 2071 to 2100.Keywords: ﬂoods, climate modeling, linear trend. RESUMO. A região leste do Estado de Santa Catarina tem um importante histórico de desastres naturais ocasionados por eventos extremos de precipitação. Inundações e deslizamentos de terra são potencializados pelo relevo acidentado e pela urbanização das cidades da região: a vegetação nativa vem sendo removida acarretando um maior escoamento superﬁcial e, consequentemente, em inundações. Desta forma, torna-se de suma importância os estudos acerca deste tipo de evento que inﬂuencia diretamente a sociedade em geral. Neste trabalho é realizada uma análise quantitativa do número de eventos severos de precipitação ocorridos nas regiões leste e norte de Santa Catarina dos últimos 60 anos, por meio de uma análise pontual, considerandoo histórico de inundações de cada cidade selecionada, além de uma projeção para o ﬁm do século de acordo com modelagem climática regional. Na análise dos resultados observou-se uma tendência linear positiva na maioria das cidades, indicando uma maior frequência deste tipo de evento nas últimas décadas, e o modelo climático HadRM3P mostra um aumento heterogêneo no número de eventos para todas as cidades no período de 2071 a 2100.Palavras-chave: inundações, modelagem climática, tendência linear.

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Impacts of high inter-annual variability of rainfall on a century of extreme hydrologic regime of northwest Australia

Hydrology and Earth System Sciences ◽

10.5194/hess-19-2057-2015 ◽

2015 ◽

Vol 19 (4) ◽

pp. 2057-2078 ◽

Cited By ~ 21

Author(s):

A. Rouillard ◽

G. Skrzypek ◽

S. Dogramaci ◽

C. Turney ◽

P. F. Grierson

Keyword(s):

Surface Water ◽

Extreme Rainfall ◽

P Value ◽

Extreme Rainfall Events ◽

Rainfall Events ◽

Annual Variability ◽

Hydrologic Regimes ◽

Inland Northwest ◽

History Of ◽

Northwest Australia

Abstract. Long-term hydrologic records provide crucial reference baselines of natural variability that can be used to evaluate potential changes in hydrologic regimes and their impacts. However, there is a dearth of studies of the hydrologic regimes for tropical drylands where intraseasonal and interannual variability in magnitude and frequency of precipitation are extreme. Here, we sought to identify the main hydroclimatic determinants of the strongly episodic flood regime of a large catchment in the semi-arid, subtropical northwest of Australia and to establish the background of hydrologic variability for the region over the last century. We used a monthly sequence of satellite images to quantify surface water expression on the Fortescue Marsh, the largest water feature of inland northwest Australia, from 1988 to 2012. We used this sequence together with instrumental rainfall data to build a statistical model with multiple linear regression and reconstruct monthly history of floods and droughts since 1912. We found that severe and intense regional rainfall events, as well as the sequence of recharge events both within and between years, determine surface water expression on the floodplain (i.e. total rainfall, number of rain days and carried-over inundated area; R2adj = 0.79; p value < 0.001, ERMSP = 56 km2). The most severe reconstructed inundation over the last century was in March 2000 (1000 km2), which is less than the 1300 km2 area required to overflow to the adjacent catchment. The Fortescue Marsh was completely dry for 32% of all years, for periods of up to four consecutive years. Extremely wet years (seven of the 100 years) caused the Marsh to remain inundated for up to 12 months; only 25% of years (9% of all months) had floods of greater than 300 km2. The prolonged, severe and consecutive yearly inundations between 1999 and 2006 were unprecedented compared to the last century. While there is high inter-annual variability in the system, if the frequency and intensity of extreme rainfall events for the region were to increase (or be similar to 1999–2006), surface water on the Marsh will become more persistent, in turn impacting its structure and functioning as a wetland.

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Risks of seasonal extreme rainfall events in Bangladesh under 1.5 and 2.0 degrees’ warmer worlds – How anthropogenic aerosols change the story

10.5194/hess-2018-400 ◽

2018 ◽

Cited By ~ 1

Author(s):

Ruksana H. Rimi ◽

Karsten Haustein ◽

Emily J. Barbour ◽

Sarah N. Sparrow ◽

Sihan Li ◽

...

Keyword(s):

Climate Change ◽

Global Warming ◽

Climate Model ◽

Substantial Reduction ◽

Extreme Rainfall ◽

Extreme Weather Events ◽

Future Climate Change ◽

Anthropogenic Aerosols ◽

Extreme Rainfall Events ◽

Rainfall Events

Abstract. Anthropogenic climate change is likely to increase the frequency of extreme weather events in future. Previous studies have robustly shown how and where climate change has already changed the risks of weather extremes. However, developing countries have been somewhat underrepresented in these studies, despite high vulnerability and limited capacities to adapt. How additional global warming would affect the future risks of extreme rainfall events in Bangladesh needs to be addressed to limit adverse impacts. Our study focuses on understanding and quantifying the relative risks of seasonal extreme rainfall events in Bangladesh under the Paris Agreement temperature goals of 1.5 °C and 2 °C warming above pre-industrial levels. In particular, we investigate the influence of anthropogenic aerosols on these risks given their likely future reduction and resulting amplification of global warming. Using large ensemble regional climate model simulations from weather@home under different forcing scenarios, we compare the risks of rainfall events under pre-industrial (natural), current (actual), 1.5 °C, and 2.0 °C warmer and greenhouse gas only (anthropogenic aerosols removed) conditions. We find that the risk of a 1 in 100 year rainfall event has already increased significantly compared with pre-industrial levels across parts of Bangladesh, with additional increases likely for 1.5 and 2.0 degree warming (of up to 5.5 times higher, with an uncertainty range of 3.5 to 7.8 times). Impacts were observed during both the pre-monsoon and monsoon periods, but were spatially variable across the country in terms of the level of impact. Results also show that reduction in anthropogenic aerosols plays an important role in determining the overall future climate change impacts; by exacerbating the effects of GHG induced global warming and thereby increasing the rainfall intensity. We highlight that the net aerosol effect varies from region to region within Bangladesh, which leads to different outcomes of aerosol reduction on extreme rainfall statistics, and must therefore be considered in future risk assessments. Whilst there is a substantial reduction in the impacts resulting from 1.5 °C compared with 2 °C warming, the difference is spatially and temporally variable, specifically with respect to seasonal extreme rainfall events.

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Mesoscale and Synoptic Environment in Three Orographically Enhanced Rain Events on the Coast of Santa Catarina (Brazil)

Weather and Forecasting ◽

10.1175/waf-d-15-0003.1 ◽

2016 ◽

Vol 31 (5) ◽

pp. 1529-1546

Author(s):

M. Laura Guimarães Rodrigues ◽

Rita Yuri Ynoue

Keyword(s):

Extreme Rainfall ◽

Heavy Rain ◽

The United States ◽

Santa Catarina ◽

Local Networks ◽

Extreme Rainfall Events ◽

Rainfall Events ◽

Unstable Environment ◽

Slow Moving ◽

Rain Events

Abstract In this study three cases of extreme rainfall events are analyzed in Florianopolis, Santa Catarina (SC), on Brazil’s coast, lying between the mountains and the South Atlantic Ocean in southeastern South America. The largest rainfall totals, 200–300 mm in 12–24 h, resulted in flash floods. ECMWF 6-hourly 1.5° × 1.5° data were used to determine the synoptic fields and quasigeostrophic forcing, along with observational data from local networks, for subsynoptic analyses. In case C1, during May 2010, there was a frontal passage. In C2 and C3 (January 2008 and February 1979, respectively) the coastline separated a ridge over the continent from a trough over the sea at the surface, with an atmosphere of low baroclinicity predominating at 500 hPa. All three events were characterized by postfrontal conditions; the presence of an anticyclone over the sea, centered at 35°–40°S; and slow-moving or quasi-stationary midlevel cyclones over the continent, at 27 °S. The circulation generated in the cyclone resulted in strong (10 m s−1) and persistent low-level east-northeast winds along the coast of SC, favoring the influx of heat and humidity on days with heavy rain. The upward motion at 850 hPa was concentrated over the affected areas and stronger than that at 500 hPa. Even so, the moist air that reached the mountain in a conditionally unstable environment rose only to middle levels. The features presented were similar to those observed for orographic rain events in Europe and the United States.

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The Influence of Geographical Factors on Extreme Rainfalls in Lampung Province

Journal of Engineering and Scientific Research ◽

10.23960/jesr.v1i1.7 ◽

2019 ◽

Vol 1 (1) ◽

pp. 33

Author(s):

M Welly

Keyword(s):

Geographical Location ◽

Daily Rainfall ◽

Extreme Rainfall ◽

Design Flood ◽

Extreme Rainfall Events ◽

Rainfall Events ◽

Ungauged Basin ◽

Flood Discharge ◽

Design Rainfall ◽

Geographical Factors

Many people in Indonesia calculate design rainfall before calculating the design flooddischarge. The design rainfall with a certain return period will eventually be convertedinto a design flood discharge by combining it with the characteristics of the watershed.However, the lack of a network of rainfall recording stations makes many areas that arenot hydrologically measured (ungauged basin), so it is quite difficult to know thecharacteristics of rain in the area concerned. This study aims to analyze thecharacteristics of design rainfall in Lampung Province. The focus of the analysis is toinvestigate whether geographical factors influence the design rainfall that occurs in theparticular area. The data used in this study is daily rainfall data from 15 rainfallrecording stations spread in Lampung Province. The method of frequency analysis usedin this study is the Gumbel method. The research shows that the geographical location ofan area does not have significant effect on extreme rainfall events. The effect of risingearth temperatures due to natural exploitation by humans tends to be stronger as a causeof extreme events such as extreme rainfall.Keywords: Influence, geographical, factors, extreme, rainfall.

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IDENTIFICATION OF EXTREME RAINFALL EVENTS USING HIGH-RESOLUTION CARBON ISOTOPE MEASUREMENTS ACROSS TREE-RINGS

10.1130/abs/2017am-306100 ◽

2017 ◽

Author(s):

Rose G. Telus ◽

◽

Brian A. Schubert

Keyword(s):

High Resolution ◽

Carbon Isotope ◽

Tree Rings ◽

Extreme Rainfall ◽

Extreme Rainfall Events ◽

Rainfall Events ◽

Isotope Measurements

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Comparing vulnerability and institutional capacities in three Latin American coastal localities in response to extreme rainfall events

Journal of Coastal Conservation ◽

10.1007/s11852-020-00790-4 ◽

2021 ◽

Vol 25 (1) ◽

Author(s):

Arturo Ruiz-Luna ◽

Claudia Martínez-Peralta ◽

Patricia P. B. Eichler ◽

Leonardo R. Teixeira ◽

Montserrat Acosta-Morel ◽

...

Keyword(s):

Latin American ◽

Extreme Rainfall ◽

Extreme Rainfall Events ◽

Rainfall Events

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Tropical cyclone contribution to extreme rainfall over southwest Pacific Island nations

Climate Dynamics ◽

10.1007/s00382-021-05680-5 ◽

2021 ◽

Author(s):

Anil Deo ◽

Savin S. Chand ◽

Hamish Ramsay ◽

Neil J. Holbrook ◽

Simon McGree ◽

...

Keyword(s):

Tropical Cyclone ◽

El Niño ◽

El Nino ◽

Extreme Rainfall ◽

Pacific Island ◽

Extreme Rainfall Events ◽

Rainfall Events ◽

Southwest Pacific ◽

Inactive Phase ◽

Pacific Island Nations

AbstractSouthwest Pacific nations are among some of the worst impacted and most vulnerable globally in terms of tropical cyclone (TC)-induced flooding and accompanying risks. This study objectively quantifies the fractional contribution of TCs to extreme rainfall (hereafter, TC contributions) in the context of climate variability and change. We show that TC contributions to extreme rainfall are substantially enhanced during active phases of the Madden–Julian Oscillation and by El Niño conditions (particularly over the eastern southwest Pacific region); this enhancement is primarily attributed to increased TC activity during these event periods. There are also indications of increasing intensities of TC-induced extreme rainfall events over the past few decades. A key part of this work involves development of sophisticated Bayesian regression models for individual island nations in order to better understand the synergistic relationships between TC-induced extreme rainfall and combinations of various climatic drivers that modulate the relationship. Such models are found to be very useful for not only assessing probabilities of TC- and non-TC induced extreme rainfall events but also evaluating probabilities of extreme rainfall for cases with different underlying climatic conditions. For example, TC-induced extreme rainfall probability over Samoa can vary from ~ 95 to ~ 75% during a La Niña period, if it coincides with an active or inactive phase of the MJO, and can be reduced to ~ 30% during a combination of El Niño period and inactive phase of the MJO. Several other such cases have been assessed for different island nations, providing information that have potentially important implications for planning and preparing for TC risks in vulnerable Pacific Island nations.

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Trends in the Frequency of Intense Precipitation Events in Southern and Southeastern Brazil during 1960–2004

Journal of Climate ◽

10.1175/2011jcli3511.1 ◽

2011 ◽

Vol 24 (7) ◽

pp. 1913-1921 ◽

Cited By ~ 33

Author(s):

Mateus da Silva Teixeira ◽

Prakki Satyamurty

Keyword(s):

Extreme Rainfall ◽

Southeastern Brazil ◽

Extreme Rainfall Event ◽

Southern Brazil ◽

Extreme Rainfall Events ◽

Rainfall Events ◽

Annual Frequency ◽

Long Term Trends ◽

Increasing Trends

Abstract A new approach to define heavy and extreme rainfall events based on cluster analysis and area-average rainfall series is presented. The annual frequency of the heavy and extreme rainfall events is obtained for the southeastern and southern Brazil regions. In the 1960–2004 period, 510 (98) and 466 (77) heavy (extreme) rainfall events are identified in the two regions. Monthly distributions of the events closely follow the monthly climatological rainfall in the two regions. In both regions, annual heavy and extreme rainfall event frequencies present increasing trends in the 45-yr period. However, only in southern Brazil is the trend statistically significant. Although longer time series are necessary to ensure the existence of long-term trends, the positive trends are somewhat alarming since they indicate that climate changes, in terms of rainfall regimes, are possibly under way in Brazil.

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