Ahmad Abu Hammad

Dr. Ahmad Abu Hammad


Research Focus & Metrics

Academic Career Length

21Years (2006-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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7 December 2010 in Land Degradation & Development
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AHAhmad Abu Hammad
Ahmad Abu Hammad
ATA. Tumeizi
A. Tumeizi

27 May 2019 in International Journal of Climatology
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Journal Article
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ASAla Salameh
Ala Salameh
SGSonia Raquel Gámiz-Fortis
Sonia Raquel Gámiz-Fortis
YCYolanda Castro-Díez
Yolanda Castro-Díez
AHAhmad Abu Hammad
Ahmad Abu Hammad
MPMaría Jesús Esteban Parra
María Jesús Esteban Parra
The temporal and spatial trends of 16 climate extreme indices based on daily maximum and minimum temperatures during the period 1987–2016 at 28 stations distributed across Israel and Palestine territories in the Levant region were annually and seasonally analysed. The nonparametric Man‐Kendall test and the Sen's slope estimator were employed for the trend analysis. Results showed that the region has significantly experienced a dominant warming trend for the last three decades, with more intense changes for minimum temperatures than for maximum. At annual scale, maximum values of minimum temperatures exhibited significant increasing trends up to 0.68°C/decade. For percentile‐based extreme temperature indices, changes detected were more pronounced than those for the absolute extreme temperature indices, with 93 and 89% of stations significantly showed increasing trends in TX90p and TN90p, respectively. The duration and fixed threshold extreme indices confirmed the trend toward a warming, with the 86% of the stations exhibited significant increasing trends in the annual occurrence of summer days (SU25) and tropical nights (TR20). Moreover, 57% of stations showed significant increasing trends in their very summer days (SU30) index. At seasonal scale, the analysis of trends for extreme temperature indices showed intense and broad significant increasing trends in all absolute extreme temperature indices. In summer, more than 75% of total stations exhibited significant increasing trends for warm days and warm nights (TX90p and TN90p). In winter and spring, 71% of the total stations also showed significant increasing trends in SU25 index, whereas the percentage of stations reached 82% in summer and 64% in autumn for significant increasing trends in TR20 index. Finally, the influence of large‐scale circulation patterns on temperature extremes was examined. The results highlighted the presence of significant correlations between most of the selected extreme temperature indices and the North Sea‐Caspian pattern at annual and seasonal scales.

2 February 2006 in Environmental Management
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AHAhmad Abu Hammad
Ahmad Abu Hammad
TBTrond Børresen
Trond Børresen


18 March 2015 in Environmental Monitoring and Assessment
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IAIssam A. Al-Khatib
Issam A. Al-Khatib
AHAhmad Abu Hammad
Ahmad Abu Hammad
OSOthman A. Sharkas
Othman A. Sharkas
CSChikashi Sato
Chikashi Sato

14 January 2022 in Atmosphere
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Journal Article
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AHAhmad Abu Hammad
Ahmad Abu Hammad
ASAla Salameh
Ala Salameh
RFRiad Qara Fallah
Riad Qara Fallah
This study aimed at analysis of the general-index change for the mean annual and seasonal precipitation in six stations in Latakia Governorate (Syria). The data of precipitation were collected for 40 consecutive years (1970–2010) in order to figure out the extent of the changes and variability in precipitation rates and the impact of this change on changes in the potential density that might cause extremely high or low precipitation rates according to Gumbel distribution of the extreme precipitation rates. Results revealed a decrease of the annual precipitation rates in all stations, the reduction in precipitation ranged from 46 to 210 mm during the whole period of the study. Spring, however, recorded the highest and statistically significant reduction, which reached 46–210 mm, while winter precipitation increased by 21–82 mm. Spring also has witnessed a decrease of about 3–9% of the total annual precipitation as compared to winter precipitation which increased by 5–8% of the total. The potential density of extremely high winter precipitation rates increased in all stations as indicated from Gumbel distribution in winter, and a greater increase took place in the probabilities of occurrence of the extremely low spring precipitation rates. This shows significant probability of occurrence of drought during spring season. By contrast, probabilities of winter precipitation rates increased more, thus winter is relatively more humid than before and spring is relatively drier than before.