Evaluation of the TRMM Product for Monitoring Drought over Paraíba State, Northeastern Brazil: A Statistical Analysis

Drought is a natural phenomenon that originates from the absence of precipitation over a certain period and is capable of causing damage to societal development. With the advent of orbital remote sensing, rainfall estimates from satellites have appeared as viable alternatives to monitor natural hazards in ungauged basins and complex areas of the world; however, the accuracies of these orbital products still need to be verified. Thus, this work aims to evaluate the performance of Tropical Rainfall Measuring Mission (TRMM) satellite rainfall estimates in monitoring the spatiotemporal behavior of droughts at multiple temporal scales over Paraíba State based on the standardized precipitation index (SPI) over 20 years (1998–2017). For this purpose, rainfall data from 78 rain gauges and 187 equally spaced TRMM cell grids throughout the region are used, and accuracy analyses are performed at the single-gauge level and in four mesoregions at eight different time scales based on 11 statistical metrics calculations divided into three different categories. The results show that in the mesoregions close to the coast, the satellite-based product is less accurate in capturing the drought behavior regardless of the evaluated statistical metrics. At the temporal scale, the TRMM is more accurate in identifying the pattern of medium-term droughts; however, there is considerable spatial variation in the accuracy of the product depending on the performance index. Therefore, it is concluded that rainfall estimates from the TRMM satellite are a valuable source of data to identify drought behavior in a large part of Paraíba State at different time scales, and further multidisciplinary studies should be conducted to monitor these phenomena more accurately based on satellite data.

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Hydrological response to different time scales of climatological drought: an evaluation of the Standardized Precipitation Index in a mountainous Mediterranean basin

Hydrology and Earth System Sciences ◽

10.5194/hess-9-523-2005 ◽

2005 ◽

Vol 9 (5) ◽

pp. 523-533 ◽

Cited By ~ 156

Author(s):

S. M. Vicente-Serrano ◽

J. I. López-Moreno

Keyword(s):

Time Scales ◽

Hydrological Cycle ◽

Standardized Precipitation Index ◽

Precipitation Index ◽

Drought Indices ◽

Long Time ◽

The Standardized Precipitation Index ◽

Hydrological Droughts ◽

Different Time Scales

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.

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Evaluation of the TRMM product for monitoring drought over Paraíba State, northeastern Brazil: a trend analysis

Scientific Reports ◽

10.1038/s41598-020-80026-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Reginaldo Moura Brasil Neto ◽

Celso Augusto Guimarães Santos ◽

Jorge Flávio Casé Braga da Costa Silva ◽

Richarde Marques da Silva ◽

Carlos Antonio Costa dos Santos ◽

...

Keyword(s):

Standardized Precipitation Index ◽

Tropical Rainfall Measuring Mission ◽

Extreme Rainfall ◽

Rain Gauge ◽

Rainfall Data ◽

Northeastern Brazil ◽

Rainfall Time Series ◽

Extreme Rainfall Events ◽

Spatiotemporal Trends ◽

The Standardized Precipitation Index

AbstractDroughts are complex natural phenomena that influence society's development in different aspects; therefore, monitoring their behavior and future trends is a useful task to assist the management of natural resources. In addition, the use of satellite-estimated rainfall data emerges as a promising tool to monitor these phenomena in large spatial domains. The Tropical Rainfall Measuring Mission (TRMM) products have been validated in several studies and stand out among the available products. Therefore, this work seeks to evaluate TRMM-estimated rainfall data's performance for monitoring the behavior and spatiotemporal trends of meteorological droughts over Paraíba State, based on the standardized precipitation index (SPI) from 1998 to 2017. Then, 78 rain gauge-measured and 187 TRMM-estimated rainfall time series were used, and trends of drought behavior, duration, and severity at eight time scales were evaluated using the Mann–Kendall and Sen tests. The results show that the TRMM-estimated rainfall data accurately captured the pattern of recent extreme rainfall events that occurred over Paraíba State. Drought events tend to be drier, longer-lasting, and more severe in most of the state. The greatest inconsistencies between the results obtained from rain gauge-measured and TRMM-estimated rainfall data are concentrated in the area closest to the coast. Furthermore, long-term drought trends are more pronounced than short-term drought, and the TRMM-estimated rainfall data correctly identified this pattern. Thus, TRMM-estimated rainfall data are a valuable source of data for identifying drought behavior and trends over much of the region.

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Hydrological response to different time scales of climatological drought: an evaluation of the standardized precipitation index in a mountainous mediterranean basin

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-2-1221-2005 ◽

2005 ◽

Vol 2 (4) ◽

pp. 1221-1246 ◽

Cited By ~ 13

Author(s):

S. M. Vicente-Serrano ◽

J. I. López-Moreno

Keyword(s):

Time Scales ◽

Hydrological Cycle ◽

Standardized Precipitation Index ◽

Precipitation Index ◽

Drought Indices ◽

Long Time ◽

The Standardized Precipitation Index ◽

Hydrological Droughts ◽

Different Time Scales

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 higher (>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 higher 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.

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Positive and Negative Phases of the Wintertime North Atlantic Oscillation and Drought Occurrence over Europe: A Multitemporal-Scale Approach

Journal of Climate ◽

10.1175/2007jcli1739.1 ◽

2008 ◽

Vol 21 (6) ◽

pp. 1220-1243 ◽

Cited By ~ 110

Author(s):

J. Ignacio López-Moreno ◽

Sergio M. Vicente-Serrano

Keyword(s):

Twentieth Century ◽

North Atlantic Oscillation ◽

Time Scales ◽

North Atlantic ◽

Standardized Precipitation Index ◽

Opposite Pattern ◽

The North ◽

The Standardized Precipitation Index ◽

Drought Occurrence ◽

Different Time Scales

Abstract In this study, droughts are analyzed using the standardized precipitation index (SPI) at different time scales for all of Europe over the period 1901–2000. The SPI is calculated at different time scales (1–12 months), as are the average values that correspond to negative and positive phases of the North Atlantic Oscillation (NAO). The responses of droughts to the phases of the NAO vary spatially, but the response also depends on the month of the year and the time scale of the analysis. During the positive/negative phases, negative/positive SPI values are generally recorded in southern Europe, with the opposite pattern recorded in northern Europe. In certain regions, significant differences in the SPI are also recorded during spring, summer, and even autumn. In several regions, the magnitude of the average SPI anomalies is noticeably different for the positive and negative phases of the NAO, indicating the asymmetric response of droughts to the NAO. The unstable response of drought occurrence is also demonstrated, at different time scales, to positive and negative phases of the NAO throughout the twentieth century. During the second half of the twentieth century, there is a strengthening of the influence of the positive phases of the NAO on droughts. In contrast, the negative phases show a weaker influence on the SPI during the second half of the twentieth century. This pattern is related to changes in the wintertime sea level pressure fields associated with positive and negative phases of the NAO.

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A novel index for ecological drought monitoring based on ecological water deficit: a case study of Northwestern China

10.5194/egusphere-egu21-5439 ◽

2021 ◽

Author(s):

Tianliang Jiang ◽

Xiaoling Su

Keyword(s):

Water Deficit ◽

Time Scales ◽

Drought Index ◽

Vegetation Index ◽

Standardized Precipitation Index ◽

Northwestern China ◽

Drought Monitoring ◽

Drought Indices ◽

Drought Severity ◽

Different Time Scales

Although the concept of ecological drought was first defined by the Science for Nature and People Partnership (SNAPP) in 2016, there remains no widely accepted drought index for monitoring ecological drought. Therefore, this study constructed a new ecological drought monitoring index, the standardized ecological water deficit index (SEWDI). The SEWDI is based on the difference between ecological water requirements and consumption, referred to as the standardized precipitation index (SPI) method, which was used to monitor ecological drought in Northwestern China (NWRC). The performances of the SEWDI and four widely-used drought indices [standardized root soil moisture index (SSI), self-calibrated Palmer drought index (scPDSI), standardized precipitation-evaporation drought index (SPEI), and SPI) in monitoring ecological drought were evaluated through comparing the Pearson correlations between these indices and the standardized normalized difference vegetation index (SNDVI) under different time scales, wetness, and water use efficiencies (WUEs) of vegetation. Finally, the rotational empirical orthogonal function (REOF) was used to decompose the SEWDI at a 12-month scale in the NWRC during 1982&#8211;2015 to obtain five ecological drought regions. The characteristics of ecological drought in the NWRC, including intensity, duration, and frequency, were extracted using run theory. The results showed that the performance of the SEWDI in monitoring ecological drought was highest among the commonly-used drought indices evaluated under different time scales [average correlation coefficient values (r) between SNDVI and drought indices: SEWDI= 0.34, SSI= 0.24, scPDSI= 0.23, SPI= 0.20, SPEI= 0.18), and the 12-month-scale SEWDI was largely unaffected by wetness and WUE. In addition, the results of the monitoring indicated that serious ecological droughts in the NWRC mainly occurred in 1982&#8211;1986, 1990&#8211;1996, and 2005&#8211;2010, primarily in regions I, II, and V, regions II, and IV, and in region III, IV, and V, respectively. This study provides a robust approach for quantifying ecological drought severity across natural vegetation areas and scientific evidence for governmental decision makers.

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Drought Monitoring in Chaharmahl-Bakhtiyari Province in Iran

Revista Brasileira de Meteorologia ◽

10.1590/0102-7786324009 ◽

2017 ◽

Vol 32 (4) ◽

pp. 615-621 ◽

Cited By ~ 1

Author(s):

Hamid Mohammadi ◽

Mojgan Abasi ◽

Javad Bazrafshan

Keyword(s):

Time Scales ◽

Normal Level ◽

Standardized Precipitation Index ◽

Drought Monitoring ◽

Maximum Frequency ◽

Drought Duration ◽

Resources Management ◽

Drought Occurrence ◽

Different Time Scales ◽

Selection Of

Abstract The monitoring of drought is the most important factor in water resources management. This study focuses on evaluation of the drought characteristics such as intensity, frequency and duration drought using Standardized Precipitation Index (SPI) in different time scales such as: SPI1, SPI3 months, during 1980-2012. The results show that selection of different time scales can be based on management goals and kind of drought. The results of the drought occurrence frequency showed that, with increase of length of time scales, drought duration will increase and maximum frequency was at the normal level and there is no particular procedure in different time scales. Furthermore, Drought patterns maps showed that the northern and central parts of study area had experienced these recent droughts more than other places, and these place have potential to destroy the lands. So, by identification of sensitivity regions can be take appropriate management to prevent damage resulting of drought.

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Nine-Year Systematic Evaluation of the GPM and TRMM Precipitation Products in the Shuaishui River Basin in East-Central China

Remote Sensing ◽

10.3390/rs12061042 ◽

2020 ◽

Vol 12 (6) ◽

pp. 1042 ◽

Cited By ~ 6

Author(s):

Xiaoying Yang ◽

Yang Lu ◽

Mou Leong Tan ◽

Xiaogang Li ◽

Guoqing Wang ◽

...

Keyword(s):

River Basin ◽

Time Scales ◽

Daily Rainfall ◽

Central China ◽

Spatiotemporal Resolution ◽

Study Region ◽

East Central ◽

Hourly Rainfall ◽

Rainfall Estimates ◽

Different Time Scales

Owing to their advantages of wide coverage and high spatiotemporal resolution, satellite precipitation products (SPPs) have been increasingly used as surrogates for traditional ground observations. In this study, we have evaluated the accuracy of the latest five GPM IMERG V6 and TRMM 3B42 V7 precipitation products across the monthly, daily, and hourly scale in the hilly Shuaishui River Basin in East-Central China. For evaluation, a total of four continuous and three categorical metrics have been calculated based on SPP estimates and historical rainfall records at 13 stations over a period of 9 years from 2009 to 2017. One-way analysis of variance (ANOVA) and multiple posterior comparison tests are used to assess the significance of the difference in SPP rainfall estimates. Our evaluation results have revealed a wide-ranging performance among the SPPs in estimating rainfall at different time scales. Firstly, two post-time SPPs (IMERG_F and 3B42) perform considerably better in estimating monthly rainfall. Secondly, with IMERG_F performing the best, the GPM products generally produce better daily rainfall estimates than the TRMM products. Thirdly, with their correlation coefficients all falling below 0.6, neither GPM nor TRMM products could estimate hourly rainfall satisfactorily. In addition, topography tends to impose similar impact on the performance of SPPs across different time scales, with more estimation deviations at high altitude. In general, the post-time IMERG_F product may be considered as a reliable data source of monthly or daily rainfall in the study region. Effective bias-correction algorithms incorporating ground rainfall observations, however, are needed to further improve the hourly rainfall estimates of the SPPs to ensure the validity of their usage in real-world applications.

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Computation of the Standardized Precipitation Index (SPI) and Its Use to Assess Drought Occurrences in Cameroon over Recent Decades

Journal of Applied Meteorology and Climatology ◽

10.1175/jamc-d-14-0032.1 ◽

2014 ◽

Vol 53 (10) ◽

pp. 2310-2324 ◽

Cited By ~ 28

Author(s):

Guy Merlin Guenang ◽

F. Mkankam Kamga

Keyword(s):

Time Scales ◽

Goodness Of Fit ◽

Standardized Precipitation Index ◽

Research Unit ◽

Distribution Functions ◽

Precipitation Index ◽

Severe Drought ◽

East Anglia ◽

The Standardized Precipitation Index ◽

Short Time

AbstractThe standardized precipitation index (SPI) is computed and analyzed using 55 years of precipitation data recorded in 24 observation stations in Cameroon along with University of East Anglia Climate Research Unit (CRU) spatialized data. Four statistical distribution functions (gamma, exponential, Weibull, and lognormal) are first fitted to data accumulated for various time scales, and the appropriate functions are selected on the basis of the Anderson–Darling goodness-of-fit statistic. For short time scales (up to 6 months) and for stations above 10°N, the gamma distribution is the most frequent choice; below this belt, the Weibull distribution predominates. For longer than 6-month time scales, there are no consistent patterns of fitted distributions. After calculating the SPI in the usual way, operational drought thresholds that are based on an objective method are determined at each station. These thresholds are useful in drought-response decision making. From SPI time series, episodes of severe and extreme droughts are identified at many stations during the study period. Moderate/severe drought occurrences are intra-annual in short time scales and interannual for long time scales (greater than 9 months), usually spanning many years. The SPI calculated from CRU gridded precipitation shows similar results, with some discrepancies at longer scales. Thus, the spatialized dataset can be used to extend such studies to a larger region—especially data-scarce areas.

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Regional and Seasonal Precipitation and Drought Trends in Ganga–Brahmaputra Basin

Water ◽

10.3390/w13162218 ◽

2021 ◽

Vol 13 (16) ◽

pp. 2218

Author(s):

Bikram Parajuli ◽

Xiang Zhang ◽

Sudip Deuja ◽

Yingbing Liu

Keyword(s):

Spatial Pattern ◽

Time Scales ◽

Standardized Precipitation Index ◽

Monthly Precipitation ◽

Seasonal Precipitation ◽

Precipitation Data ◽

Rain Gauges ◽

Geographical Regions ◽

Brahmaputra Basin ◽

Different Time Scales

Satellite-based precipitation products can be a better alternative of rain gauges for hydro-meteorological studies in data-poor regions. This study aimed to evaluate how regional and seasonal precipitation and drought patterns had changed in the Ganga–Brahmaputra Basin between 1983 and 2020 with PERSIANN-CDR precipitation data. The spatial pattern of winter drought, monsoon drought, and Standardized Precipitation Index (SPI) calculated for different time scales were evaluated using principal component analysis. Ganga–Brahmaputra is one of the most populated river basins that flows through different geographical regions. Rain gauges are heterogeneously distributed in the basin due to its complex orography, highlighting the significance of gridded precipitation products over gauge observations for climate studies. Annual and monthly precipitation trends between 1983 and 2020 were evaluated using the original and modified Mann–Kendall trend test, and annual precipitation in the basin was found to be declining at a rate of 5.8 mm/year. An increasing trend was observed in pre-monsoon rainfall, whereas precipitation exhibited a decreasing trend for other months. Results of the Pettitt test showed precipitation time series was inhomogeneous and changepoint occurred around 2000. Decreasing trends of SPI indicated increasing frequency and intensity of drought events. Winter drought showed a clear spatial pattern in the basin; however, SPIs calculated for different time scales and monsoon drought had complex spatial patterns. This study demonstrates the applicability of satellite-based PERSIANN-CDR precipitation data in climate research in the Ganga–Brahmaputra Basin.

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Drought Monitoring Utility using Satellite-Based Precipitation Products over the Xiang River Basin in China

Remote Sensing ◽

10.3390/rs11121483 ◽

2019 ◽

Vol 11 (12) ◽

pp. 1483 ◽

Cited By ~ 6

Author(s):

Qian Zhu ◽

Yulin Luo ◽

Dongyang Zhou ◽

Yue-Ping Xu ◽

Guoqing Wang ◽

...

Keyword(s):

River Basin ◽

Drought Index ◽

Standardized Precipitation Index ◽

Tropical Rainfall Measuring Mission ◽

Drought Monitoring ◽

In Situ Observations ◽

Remote Sensing Techniques ◽

Xiang River ◽

The Standardized Precipitation Index

Drought is a natural hazard disaster that can deeply affect environments, economies, and societies around the world. Therefore, accurate monitoring of patterns in drought is important. Precipitation is the key variable to define the drought index. However, the spare and uneven distribution of rain gauges limit the access of long-term and reliable in situ observations. Remote sensing techniques enrich the precipitation data at different temporal–spatial resolutions. In this study, the climate prediction center morphing (CMORPH) technique (CMORPH-CRT), the tropical rainfall measuring mission (TRMM) multi-satellite precipitation analysis (TRMM 3B42V7), and the integrated multi-satellite retrievals for global precipitation measurement (IMERG V05) were evaluated and compared with in situ observations for the drought monitoring in the Xiang River Basin, a humid region in China. A widely-used drought index, the standardized precipitation index (SPI), was chosen to evaluate the drought monitoring utility. The atmospheric water deficit (AWD) was used for comparison of the drought estimation with SPI. The results were as follows: (1) IMERG V05 precipitation products showed the highest accuracy against grid-based precipitation, followed by CMORPH-CRT, which performed better than TRMM 3B42V7; (2) IMERG V05 showed the best performance in SPI-1 (one-month SPI) estimations compared with CMORPH-CRT and TRMM 3B42V7; (3) SPI-1 was more suitable for drought monitoring than AWD in the Xiang River Basin, because its high R-values and low root mean square error (RMSE) compared with the corresponding index based on in situ observations; (4) drought conditions in 2015 were apparently more severe than that in 2016 and 2017, with the driest area mainly distributed in the southwest part of the Xiang River Basin.

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