scholarly journals Using the Local Drought Data and GRACE/GRACE-FO Data to Characterize the Drought Events in Mainland China from 2002 to 2020

2021 ◽  
Vol 11 (20) ◽  
pp. 9594
Author(s):  
Lilu Cui ◽  
Cheng Zhang ◽  
Zhicai Luo ◽  
Xiaolong Wang ◽  
Qiong Li ◽  
...  
Keyword(s):  
Mainland China ◽  
Severity Index ◽  
Precipitation Anomaly ◽  
Probability Of Detection ◽  
Drought Severity ◽  
Drought Event ◽  
Loss Assessment ◽  
Drought Characteristics ◽  
Disaster Loss ◽  
Gravity Recovery

Accurate quantification of drought characteristics helps to achieve an objective and comprehensive analysis of drought events and to achieve early warning of drought and disaster loss assessment. In our study, a drought characterization approach based on drought severity index derived from Gravity Recovery and Climate Experiment (GRACE) and its Follow-On (GRACE-FO) data was used to quantify drought characteristics. In order to improve drought detection capability, we used the local drought data as calibration criteria to improve the accuracy of the drought characterization approach to determine the onset of drought. Additionally, the local precipitation data was used to test drought severity determined by the calibrated drought characterization approach. Results show that the drought event probability of detection (POD) of this approach in the four study regions increased by 61.29%, 25%, 94.29%, and 66.86%, respectively, after calibration. We used the calibrated approach to detect the drought events in Mainland China (MC) during 2016 and 2019. The results show that CAR of the four study regions is 100.00%, 92.31%, 100.00%, and 100.00%. Additionally, the precipitation anomaly index (PAI) data was used to evaluate the severity of drought from 2002 to 2020 determined by the calibrated approach. The results indicate that both have a strong similar spatial distribution. Our analysis demonstrates that the proposed approach can serve a useful tool for drought monitoring and characterization.

scholarly journals DROUGHT ASSESSMENT OF IRAN USING THE MDI INDEX

2019 ◽  
Vol XLII-4/W18 ◽  
pp. 659-663
Author(s):  
I. Kordpour ◽  
S. Farzaneh ◽  
R. Shahhoseini
Keyword(s):  
Severity Index ◽  
Drought Indices ◽  
Drought Severity ◽  
Drought Event ◽  
Data Types ◽  
Drought Assessment ◽  
Multiple Data ◽  
Moderate Drought ◽  
Terrestrial Water ◽  
Gravity Recovery

Abstract. Drought is one of the most common natural phenomena. Many indices using multiple data types have been created, and their success at recognizing periods of extreme wetness and dryness has been well documented. The merit of the method is the utilization of terrestrial water storage (TWS) variations from Gravity Recovery and Climate Experiment (GRACE) quantification of drought intensity. Alongside with these observations, we add precipitation data to equations. In this study, we analyze Merged-dataset Drought index (MDI) using GRACE-derived TWSA and precipitation in Iran, where most of the area is desert and mountain in the middle and South of the country. Our sample period is from January 2003 to December 2014. MDI shows a strong correlation with existing drought indices, especially with the Palmer Drought Severity Index (PDSI). Based on the obtained results, MDI indicates a moderate Drought event in 2008 and 2012–2015, which is compatible with the recorded result of PDSI. The longest drought took 22 months (from January 2008 to October 2009). Interestingly, the coefficient of correlation between MDI and PDSI is 0.67.

Flash Drought Characteristics by Different Severities in Humid Subtropical Basins: A Case Study in the Gan River Basin, China

2021 ◽  
pp. 1-44
Author(s):  
Yuqing Zhang ◽  
Qinglong You ◽  
Guangxiong Mao ◽  
Changchun Chen ◽  
Xin Li ◽  
...  
Keyword(s):  
Soil Moisture ◽  
River Basin ◽  
Vapour Pressure Deficit ◽  
Severity Index ◽  
Drought Severity ◽  
Rapid Decline ◽  
Drought Risk ◽  
Drought Event ◽  
Drought Period ◽  
Drought Intensity

AbstractIt is essential to assess flash drought risk based on a reliable flash drought intensity (severity) index incorporating comprehensive information of the rapid decline (“flash”) in soil moisture towards drought conditions and soil moisture thresholds belonging to the “drought” category. In this study, we used the Gan River Basin as an example to define a flash drought intensity index that can be calculated for individual time steps (pentads) during a flash drought period over a given grid (or station). The severity of a complete flash drought event is the sum of the intensity values during the flash drought. We explored the spatial and temporal characteristics of flash droughts with different grades based on their respective severities. The results show that decreases in total cloud cover, precipitation, and relative humidity, as well as increases in 500 hPa geopotential height, convective inhibition, temperature, vapour pressure deficit, and wind speed can create favorable conditions for the occurrence of flash droughts. Although flash droughts are relatively frequent in the central and southern parts of the basin, the severity is relatively high in the northern part of the basin due to longer duration. Flash drought severity shows a slightly downward trend due to decreases in frequency, duration, and intensity from 1961 to 2018. Extreme and exceptional flash droughts decrease significantly while moderate and severe flash droughts trend slightly upward. Flash drought severity appears to be more affected by the interaction between duration and intensity as the grade increases from mild to severe. The frequency and duration of flash droughts are higher in July to October. The southern part of the basin is more prone to moderate and severe flash droughts, while the northern parts of the basin are more vulnerable to extreme and exceptional flash droughts due to longer durations and greater severities than other parts. Moderate, severe, extreme, and exceptional flash droughts occurred approximately every 3-6, 5-15, 10-50, and 30-200 year intervals, respectively, based on the copula analysis.

scholarly journals Identification of Drought and Performance Evaluation of MODIS and TRMM through Remote Sensing: A Case Study in North and West Africa during 2002–2018

2020 ◽  
Author(s):  
Malak Henchiri ◽  
Qi Liu ◽  
Bouajila Essifi ◽  
Shahzad Ali ◽  
Wilson Kalisa ◽  
...  
Keyword(s):  
Remote Sensing ◽  
West Africa ◽  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Severity Index ◽  
Precipitation Anomaly ◽  
Drought Severity ◽  
Monthly Precipitation ◽  
Water Index ◽  
And Performance

North and West Africa are the most vulnerable regions to drought, due to the high variation in monthly precipitation. An accurate and efficient monitoring of drought is essential. In this study, we use TRMM data with remote sensing tools for effective monitoring of drought. The Drought Severity Index (DSI), Temperature Vegetation Drought Index (TVDI), Normalized Difference Vegetation Index (NDVI), and Normalized Vegetation Supply Water Index (NVSWI) are more useful for monitoring the drought over North and West Africa. To classify the areas affected by drought, we used the TRMM spatial maps to verify the TVDI, DSI and NVSWI indexes derived from MODIS. The DSI, TVDI, NVSWI and Monthly Precipitation Anomaly (NPA) indexes with the employ of MODIS-derived ET/PET and NDVI were chosen for monitoring the drought in the study area. The seasonal spatial correlation between the DSI, NPA, NVWSI, NDVI, TVDI and TCI indicates that NVSWI, NDVI and DSI present an excellent monitor of drought indexes. The change trend of drought from 2002 to 2018 was also characterized. The frequency of drought showed a decrease during this period.

scholarly journals Evaluation of Drought Characteristics in Iraq using SC-PDSI

2018 ◽  
Vol 6 (4) ◽  
pp. 177-182
Author(s):  
Thaer K. Jawad ◽  
Osama T. Al-Taai ◽  
Yaseen K. Al-Timimi
Keyword(s):  
Severity Index ◽  
Climatic Research Unit ◽  
Drought Severity ◽  
Arid Zones ◽  
Severe Drought ◽  
Drought Characteristics ◽  
Dry Spell ◽  
Desert Zone ◽  
Semi Arid ◽  
Run Theory

Evaluation of drought characteristics in Iraq by analysis annual growing season of Self-Calibrating Palmer Drought Severity Index (SC-PDSI) for three climatic zones using run theory method. The efficiency of SC-PDSI for drought monitoring was examined from compared with Rainfall Departure from the mean (RD) for three zones (Arid and Semi-Arid, Steppes and Desert) for the period 1981-2015, were derived from Climatic Research Unit (CRU). The spatial interpolation techniques in ArcGIS package has been used, to cover the whole extent of country and extracting the zones. Statistical methods were applied to compute the probability of drought events at every zone. The results showed the years 1999, 2000, 2008 and 2009 experienced droughts in all zones except the desert zone where was experienced severe drought in 2012, while the years 1982 and 1988 experienced received precipitation above-average in all zones. The values of standard deviation of precipitation were compared with precipitation anomalies for each zone, the drier seasons are (2007-2008) and (1998-1999) in all Zones. The wetter seasons are (1987-1988) in Arid and Semi-Arid and Steppes zone, (1994-1995) and (1997-1998) are wetter seasons in Desert zone. Using run theory, the steppes zone have experienced more severe droughts than other zones evaluated in this study and the most susceptible areas to dry spell are steppes and Arid and Semi-Arid Zones during study period. While the desert zone experienced less droughts.

scholarly journals Estimating the water needed to end the drought or reduce the drought severity in the Carpathian region

2015 ◽  
Vol 19 (1) ◽  
pp. 177-193 ◽  
Author(s):  
T. Antofie ◽  
G. Naumann ◽  
J. Spinoni ◽  
J. Vogt
Keyword(s):  
Pannonian Basin ◽  
Quantitative Measure ◽  
Severity Index ◽  
Drought Severity ◽  
Severe Drought ◽  
Drought Event ◽  
Local Conditions ◽  
Drought Period ◽  
Carpathian Region ◽  
Drought Recovery

Abstract. A drought severity climatology for the Carpathian region has been produced using the self-calibrating Palmer Drought Severity Index (Sc-PDSI) for the period 1961–2010. Using the Sc-PDSI and the assumptions of the Palmer drought model (PDM) the precipitation required for drought termination (when Sc-PDSI reaches −0.5) and amelioration (when Sc-PDSI reaches −2.0) are computed for periods of 1, 3, and 6 months. We discuss the reduction of the uncertainty in the determination of the beginning and ending of drought conditions, and provide a quantitative measure of the probability that any drought could be ameliorated or terminated. We present how the spatial variability of the amount of water needed for drought recovery and the climatological probability of receiving that amount of water is determined by the local conditions against the general climate characteristics of a small area such as the Carpathian region. Regionally, the Pannonian Basin, the Transylvanian Plateau and the external Carpathian foothills and plains in the southern and eastern part of the region require the highest quantity of precipitation to recover from a drought while having the lowest climatological probabilities for such amounts of rainfall. High precipitation amounts over the northern and northwest part of the region result in higher soil moisture supplies and higher climatological probabilities to end a given drought event. Moreover, the succession and/or predominance of particular types of general atmospheric circulation patterns produce a seasonal cycle and inter-annual variability of precipitation that is quantitatively reflected in the excess of precipitation that is above normal required for drought recovery. Overall, the results of this study provide an overview on the chances of recovery from a drought period with moderate or severe drought and present information useful in decision making in water and drought management.

scholarly journals Spatial and Temporal Characterization of Drought Events in China Using the Severity-Area-Duration Method

2020 ◽  
Author(s):  
Xiaoli Yang
Keyword(s):  
Arid Region ◽  
Water Cycle ◽  
Global Climate ◽  
Severity Index ◽  
Drought Severity ◽  
Historical Period ◽  
Severe Drought ◽  
Drought Event ◽  
Long Duration ◽  
Semi Arid Region

<p>Global climate change not only affects the processes within the water cycle but also leads to the frequent occurrences of local and regional extreme drought events. In China, spatial and temporal characterizations of drought events and their future changing trends are of great importance in water resources planning and management. In this study, we employed self-calibrating Palmer drought severity index (SC-PDSI), cluster algorithm, and severity-area-duration (SAD) methods to identify drought events and analyze the spatial and temporal distributions of various drought characteristics in China using observed data and CMIP5 model outputs. Results showed that during the historical period (1961–2000), the drought event of September 1965 was the most severe, affecting 47.07% of the entire land area of China, and shorter duration drought centers (lasting less than 6 months) were distributed all over the country. In the future (2021–2060), under both RCP[CF1]  4.5 and RCP 8.5 scenarios, drought is projected to occur less frequently, but the duration of the most severe drought event is expected to be longer than that in the historical period. Furthermore, drought centers with shorter duration are expected to occur throughout China, but the long-duration drought centers (lasting more than 24 months) are expected to mostly occur in the west of the arid region and in the northeast of the semi-arid region.</p>

scholarly journals Spatiotemporal Variation of Drought Characteristics Based on Standardized Precipitation Index in Central Java over 1990-2010

2021 ◽  
Vol 893 (1) ◽  
pp. 012022
Author(s):  
Misnawati ◽  
R Boer ◽  
F Ramdhani
Keyword(s):  
Standardized Precipitation Index ◽  
Rain Gauge ◽  
Precipitation Index ◽  
Extreme Drought ◽  
Drought Severity ◽  
Severe Drought ◽  
Drought Event ◽  
Drought Characteristics ◽  
Central Java ◽  
Moderate Drought

Abstract Drought is a natural hazard that results from a deficiency of precipitation, leading to low soil moisture and river flows, reduced storage in reservoirs, and less groundwater recharge. This study investigates the spatial variations of drought characteristics (drought event frequency, duration, severity, and intensity). This study using the Standardized Precipitation Index (SPI) to analyse the drought characteristics in Central Java during 1990-2010. The rain gauge station data and CHIRPS rainfall data over Central Java is used to calculate the SPI index. The SPI was calculated at multiple timescales (1-, 3-, 6-, 12-, 24- and 48-month), the run theory was used for identification and characterization of drought events. Analysis of drought characteristics by SPI from 1990 to 2010 shows the longest drought event is four months, the maximum drought severity is 6.06, and the maximum drought intensity is 2.02. El Nino year probability drought occurrence reached 100% in August for moderate drought, severe drought, and extreme drought category, whereas the probability drought occurrences in the Normal and La Nina year range 0-70% for moderate drought, 0-50% for severe drought category and 0-40% for extreme drought category. The results of this study may help inform researchers and local policymakers to develop strategies for managing drought.

scholarly journals EVALUATION OF DROUGHT IN IRAQ USING DSI. BY REMOTE SENSING

2018 ◽  
Vol 49 (6) ◽  
Author(s):  
Jawad &et al.
Keyword(s):  
Arid Zone ◽  
Potential Evapotranspiration ◽  
Severity Index ◽  
Precipitation Anomaly ◽  
Drought Severity ◽  
Simulation Group ◽  
Precipitation Anomalies ◽  
Desert Zone ◽  
Semi Arid ◽  
Run Theory

Evaluation of drought patterns in Iraq and determining the most susceptible areas of this phenomenon were analyzed, using the remotely-sensed Drought Severity Index (DSI) through analysis the daily and annual DSI for three zones over Iraq, also have been analyzed DSI time series using run theory to evaluate the characteristics of drought in Iraq. The efficiency of DSI for drought monitoring was examined from compared with Percentage of Precipitation Anomaly (PPA) for three zones (Arid and Semi-Arid, Steppes and Desert), and compared with drought indicators (Evapotranspiration (ET), Potential evapotranspiration (PET) and total annual precipitation (PRE)) for the period 2000-2011, were derived from the Numerical Terradynamic Simulation Group (NTSG). The spatial interpolation techniques in Geographic Information System (GIS) package has been used, to cover the whole extent of country and extracting the zones. Statistical methods were applied to compute the probability of drought events at every zone. The results showed the drier year is 2008, the wetter years are 2001 in Desert zone and 2003 in steppes and Arid and Semi-Arid Zone zones. The results also showed a significant fluctuation in precipitation from the average, especially at Arid and Semi-Arid Zone when compared with other zones. The values of standard deviation of precipitation were compared with precipitation anomalies for each zone, Arid and Semi-Arid is the drier zone in 2007-2008, the wetter zone is also Arid and Semi-Arid in 2002-2003. Using run theory, the drier Zone is Arid and Semi-Arid and the wetter Zone is steppes during study period.

scholarly journals Hydroclimatic Extremes Evaluation Using GRACE/GRACE-FO and Multidecadal Climatic Variables over the Nile River Basin

2021 ◽  
Vol 13 (4) ◽  
pp. 651
Author(s):  
Zemede M. Nigatu ◽  
Dongming Fan ◽  
Wei You ◽  
Assefa M. Melesse
Keyword(s):  
River Basin ◽  
Monitoring And Evaluation ◽  
Holistic Approach ◽  
Severity Index ◽  
Drought Severity ◽  
Nile River ◽  
Climatic Regions ◽  
Nile River Basin ◽  
Major Floods ◽  
Gravity Recovery

Hydroclimatic extremes such as droughts and floods triggered by human-induced climate change are causing severe damage in the Nile River Basin (NRB). These hydroclimatic extremes are not well studied in a holistic approach in NRB. In this study, the Gravity Recovery and Climate Experiment (GRACE) mission and its Follow on mission (GRACE-FO) derived indices and other standardized hydroclimatic indices are computed for developing monitoring and evaluation methods of flood and drought. We evaluated extreme hydroclimatic conditions by using GRACE/GRACE-FO derived indices such as water storage deficits Index (WSDI); and standardized hydroclimatic indices (i.e., Palmer Drought Severity Index (PDSI) and others). This study showed that during 1950–2019, eight major floods and ten droughts events were identified based on standardized-indices and GRACE/GRACE-FO-derived indices. Standardized-indices mostly underestimated the drought and flood severity level compared to GRACE/GRACE-FO derived indices. Among standardized indices PDSI show highest correlation (r2 = 0.72) with WSDI. GRACE-/GRACE-FO-derived indices can capture all major flood and drought events; hence, it may be an ideal substitute for data-scarce hydro-meteorological sites. Therefore, the proposed framework can serve as a useful tool for flood and drought monitoring and a better understanding of extreme hydroclimatic conditions in NRB and other similar climatic regions.

scholarly journals Analysis of the Influencing Factors of Drought Events Based on GRACE Data under Different Climatic Conditions: A Case Study in Mainland China

Water ◽  
2021 ◽  
Vol 13 (18) ◽  
pp. 2575 ◽  
Author(s):  
Lilu Cui ◽  
Cheng Zhang ◽  
Chaolong Yao ◽  
Zhicai Luo ◽  
Xiaolong Wang ◽  
...  
Keyword(s):  
Southern Oscillation ◽  
Mainland China ◽  
Severity Index ◽  
Normal Operation ◽  
Drought Severity ◽  
Monsoon Climate ◽  
Related Factors ◽  
Extreme Climate ◽  
Subtropical Monsoon Climate ◽  
Drought Severity Index

The occurrence of droughts has become more frequent, and their intensity has increased in mainland China. With the aim of better understanding the influence of climate background on drought events in this region, we analyzed the role of the drought-related factors and extreme climate in the formation of droughts by investigating the relationship between the drought severity index (denoted as GRACE-DSI) based on the terrestrial water storage changes (TWSCs) derived from Gravity Recovery and Climate Experiment (GRACE) time-variable gravity fields and drought-related factors/extreme climate. The results show that GRACE-DSI was consistent with the self-calibrating Palmer Drought Severity Index in mainland China, especially for the subtropical monsoon climate, with a correlation of 0.72. Precipitation (PPT) and evapotranspiration (ET) are the main factors causing drought events. However, they play different roles under different climate settings. The regions under temperate monsoon climate and subtropical monsoon climate were more impacted by PPT, while ET played a leading role in the regions under temperate continental climate and plateau mountain climate. Moreover, El Niño–Southern Oscillation (ENSO) and North Atlantic Oscillation (NAO) events mainly caused abnormalities in PPT and ET by affecting the strength of monsoons (East Asian and Indian monsoon) and regional highs (Subtropical High, Siberian High, Central Asian High, etc.). As a result, the various affected regions were prone to droughts during ENSO or NAO events, which disturbed the normal operation of atmospheric circulation in different ways. The results of this study are valuable in the efforts to understand the formation mechanism of drought events in mainland China.

Sign in / Sign up

Export Citation Format

Share Document