Trend analysis of extreme precipitation events across Iran using percentile indices

Mahbod, Mehdi; Rafiee, Mohammad Rafie

doi:10.1002/joc.6708

Cited by 9 publications

(3 citation statements)

References 58 publications

(108 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The company has 2,991 rain gauges across Iran, the data of 741 stations, which were continuous from 1985 and 2016. The quality and homogeneity of the data were controlled, as described in Mahbod and Rafiee (2021). Data from 512 rain gauge stations were selected for the study.…”

Section: Methodsmentioning

confidence: 99%

Spatio‐temporal variations of wet and dry spells in Iran and their association with large‐scale climatic indices

Mahbod

Mashayekhi

Rafiee

et al. 2023

Intl Journal of Climatology

Self Cite

View full text Add to dashboard Cite

The spatial and temporal variations of wet and dry spells may be related to large-scale climatic indices. To date, no comprehensive study has been conducted on Iran's spatial and temporal variations of wet and dry spells. To fill this gap, 14 wet/dry spell indices were calculated for 512 rain gauges across Iran from 1985 to 2016. The modified non-parametric Mann-Kendall test was then used to examine the temporal variations of wet and dry spell indices.Whether any relationships between spell indices and 13 large-scale climatic indicators existed was determined. The maps showing the degree of correlation between wet/dry spell indices and two climatic indicators that reflect shortand long-term El Niño oscillation were presented. The results demonstrated that precipitation typically occurs in bursts of 1 or 2 days in length, with most of the annual precipitation coming from a few exceptionally heavy or extreme events. Most dry spells in Iran occur from 6 to 27 days or longer. The length, frequency, and intensity of wet spells declined in southern Iran while expanding in northern Iran. However, extreme wet spells have intensified significantly across the country. When El Niño occurs, Iran experiences wetter weather. However, long-term oscillations in sea-surface temperatures in the Pacific Ocean are found to be significantly correlated with wet/dry spells, outperforming those obtained for shorter periods. A smaller portion of the country showed a significant correlation in extreme spell indices, though.

show abstract

Section: Methodsmentioning

confidence: 99%

Spatio‐temporal variations of wet and dry spells in Iran and their association with large‐scale climatic indices

Mahbod

Mashayekhi

Rafiee

et al. 2023

Intl Journal of Climatology

Self Cite

View full text Add to dashboard Cite

show abstract

“…Between the years 1985 and 2016, the company consistently gathered data from a total of 741 rain gauges located throughout Iran. Mahbod and Rafiee (2021) provide a comprehensive account of the measures taken to ensure the consistency and high quality of our data. The study utilized data obtained from a total of 512 distinct rain gauge stations.…”

Section: Study Areamentioning

confidence: 99%

An inovative regional frequency analysis approach for robust extreme precipitation assessment in data-rich and climatically diverse regions

Mahbod,

Ebrahimiat,

Mahmoodi-Eshkaftaki

et al. 2024

Preprint

Self Cite

View full text Add to dashboard Cite

This study addresses regional frequency analysis (RFA) uncertainties caused by difficulties in identifying homogeneous subregions and choosing the best regional frequency distributions. The study modifies Hosking and Wallis (1997)'s approach to improve regionalization, especially in regions with many gauge stations. The proposed method uses 512 Iranian gauges to identify three primary regions based on annual precipitation patterns. Examining data uniformity, regional variations, frequency distributions, and quantiles for exceptional events are crucial. L-moments are important in the analysis because they estimate distribution parameters and help evaluate heterogeneity and choose distributions. The study emphasizes the importance of considering distributional characteristics beyond the mean to ensure homogeneous clusters. The findings indicate that annual precipitation patterns in Iran are spatially heterogeneous. Despite challenges, the proposed regionalization approach finds homogeneous regions that can be represented by fitted distributions. The approach's ability to accommodate spatial intricacies and tailor analysis to specific climates is shown by disaggregated area fit assessments. Thus, the study illuminates Iran's hydrological conditions-specific RFA methodology. This improves extreme precipitation estimates and aids water resource management and strategic planning. The methodology can meet different user needs and be implemented in comparable regions worldwide.

show abstract

“…The rank-based non-parametric Mann-Kendall (MK) test is widely used to detect the direction and statistical significance of trends in hydro-meteorological data. The World Meteorological Organization recommends the MK test because of its applicability to nonnormal data without being influenced by outliers or missing values [40][41][42].…”

Section: Trend Analysismentioning

confidence: 99%

Climate-Induced Perspective Variations in Irrigation Schedules and Design Water Requirements for the Rice–Wheat System

Ahmad

Choi

2021

Agronomy

View full text Add to dashboard Cite

Conceptualizing the implications of climate change for crop evapotranspiration (ETc) and subsequent net irrigation water requirement (NIWR) is critical to sustaining Pakistan’s agriculture and food security. In this article, future ETc, NIWR, and design water requirements (DWR) were projected for the rice–wheat system of Punjab, Pakistan. Consistently increasing temperatures signify an impending hotter transition in the future thermal regime, accompanied by a substantial increase in monsoon rainfall. Future climate warming accelerated ETc and NIWR, which were compensated by 2–5 and 1–2 additional irrigations during the rice and wheat seasons, respectively. Future rice and wheat required 13–18 and 2–5 irrigations per season, respectively. Effective rainfall increments did not compensate for the warming-driven higher ETc and NIWR because of uneven and erratic rainfall distribution. Rainfall occurrence and the duration of peak irrigation demand were mismatched, resulting in surplus rainwater availability during the future rice season. The results suggest that DWR for 5- and 10-year return period droughts during the baseline period (965 and 1000 mm, respectively) should be revised to accommodate the additional 100–200 mm of irrigation water per season; otherwise, the study area will face an acute water shortage in the future.

show abstract

Trend analysis of extreme precipitation events across Iran using percentile indices

Cited by 9 publications

References 58 publications

Spatio‐temporal variations of wet and dry spells in Iran and their association with large‐scale climatic indices

Spatio‐temporal variations of wet and dry spells in Iran and their association with large‐scale climatic indices

An inovative regional frequency analysis approach for robust extreme precipitation assessment in data-rich and climatically diverse regions

Climate-Induced Perspective Variations in Irrigation Schedules and Design Water Requirements for the Rice–Wheat System

Contact Info

Product

Resources

About