scholarly journals Spatiotemporal Variation of Precipitation Regime in China from 1961 to 2014 from the Standardized Precipitation Index

2016 ◽  
Vol 5 (11) ◽  
pp. 194 ◽  
Author(s):  
Xuefeng Yuan ◽  
Jinshi Jian ◽  
Gang Jiang
2020 ◽  
Vol 13 (4) ◽  
pp. 1483
Author(s):  
André Aires De Farias ◽  
Francisco de Assis Salviano De Sousa

Objetivou-se identificar e analisar os períodos de secas na sub-bacia hidrográfica do Rio Taperoá (SBHRT). Dados pluviométricos, série 1963-2014, foram utilizados para analisar a severidade dos anos secos, por meio do índice padronizado de precipitação. Verificou-se que a maioria das secas que ocorreram na SBHRT se enquadram na categoria moderada, seguido por severa e extrema. A SBHRT foi atingida por secas severas e extremas durante todas as décadas analisadas, no entanto, o maior número delas ocorreu nas décadas de 1980, 1990, 2000 e 2010. A seca mais grave foi a de 1998-2000, seguido pela de 1979-1985. A seca de 2012-2014 não foi a mais grave porque a precipitação foi acima da ocorrida no período de 1998-2000 e 1979-1985, houve também maior investimento em ações de convivência com as secas e programas sociais implantados pelos governos.  Characterization and analysis of droughts in sub-basin hydrographic of the Taperoá River  A B S T R A C TThis study aimed to identify and analyze the periods of droughts in sub-basin hydrographic of the Taperoá River (SBHTR). Rainfall data, serie 1963-2014, were used to analyze the severity of the dry years, through the standardized precipitation index (SPI). It was found that most of droughts in SBHTR occurred into the category moderate, following by severe and extreme. The SBHTR was hit by severe and extreme dried for all analyzed decades, however, as many of them occurred in the decades of 1980, 1990, 2000 and 2010. The most severe drought was the from 1998-2000, followed by 1979-1985. The drought of 2012-2014 was not the more serious because the precipitation was above occurred in 1998-2000 and 1979-1985 period, there was also greater investment in coexistence actions with droughts and social programs implemented by governments.Keywords: category of drought, precipitation regime, severity of drought.


2005 ◽  
Vol 9 (5) ◽  
pp. 523-533 ◽  
Author(s):  
S. M. Vicente-Serrano ◽  
J. I. López-Moreno

Abstract. At present, the Standardized Precipitation Index (SPI) is the most widely used drought index to provide good estimations about the intensity, magnitude and spatial extent of droughts. The main advantage of the SPI in comparison with other indices is the fact that the SPI enables both determination of drought conditions at different time scales and monitoring of different drought types. It is widely accepted that SPI time scales affect different sub-systems in the hydrological cycle due to the fact that the response of the different water usable sources to precipitation shortages can be very different. The long time scales of SPI are related to hydrological droughts (river flows and reservoir storages). Nevertheless, few analyses empirically verify these statements or the usefulness of the SPI time scales to monitor drought. In this paper, the SPI at different time scales is compared with surface hydrological variables in a big closed basin located in the central Spanish Pyrenees. We provide evidence about the way in which the longer (>12 months) SPI time scales may not be useful for drought quantification in this area. In general, the surface flows respond to short SPI time scales whereas the reservoir storages respond to longer time scales (7–10 months). Nevertheless, important seasonal differences can be identified in the SPI-usable water sources relationships. This suggests that it is necessary to test the drought indices and time scales in relation to their usefulness for monitoring different drought types under different environmental conditions and water demand situations.


2013 ◽  
Vol 17 (6) ◽  
pp. 2359-2373 ◽  
Author(s):  
E. Dutra ◽  
F. Di Giuseppe ◽  
F. Wetterhall ◽  
F. Pappenberger

Abstract. Vast parts of Africa rely on the rainy season for livestock and agriculture. Droughts can have a severe impact in these areas, which often have a very low resilience and limited capabilities to mitigate drought impacts. This paper assesses the predictive capabilities of an integrated drought monitoring and seasonal forecasting system (up to 5 months lead time) based on the Standardized Precipitation Index (SPI). The system is constructed by extending near-real-time monthly precipitation fields (ECMWF ERA-Interim reanalysis and the Climate Anomaly Monitoring System–Outgoing Longwave Radiation Precipitation Index, CAMS-OPI) with monthly forecasted fields as provided by the ECMWF seasonal forecasting system. The forecasts were then evaluated over four basins in Africa: the Blue Nile, Limpopo, Upper Niger, and Upper Zambezi. There are significant differences in the quality of the precipitation between the datasets depending on the catchments, and a general statement regarding the best product is difficult to make. The generally low number of rain gauges and their decrease in the recent years limits the verification and monitoring of droughts in the different basins, reinforcing the need for a strong investment on climate monitoring. All the datasets show similar spatial and temporal patterns in southern and north-western Africa, while there is a low correlation in the equatorial area, which makes it difficult to define ground truth and choose an adequate product for monitoring. The seasonal forecasts have a higher reliability and skill in the Blue Nile, Limpopo and Upper Niger in comparison with the Zambezi. This skill and reliability depend strongly on the SPI timescale, and longer timescales have more skill. The ECMWF seasonal forecasts have predictive skill which is higher than using climatology for most regions. In regions where no reliable near-real-time data is available, the seasonal forecast can be used for monitoring (first month of forecast). Furthermore, poor-quality precipitation monitoring products can reduce the potential skill of SPI seasonal forecasts in 2 to 4 months lead time.


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