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Climate Change 2016
October 27-29, 2016
Volume 7, Issue 9(Suppl)
J Earth Sci Clim Change
ISSN: 2157-7617 JESCC, an open access journal
conferenceseries
.com
October 24-26, 2016 Valencia, Spain
World Conference on
Climate Change
Solar activity and its influence on the variations of the precipitable water vapor- case study of central
Arabian Peninsula
Maghrabi A H
King Abdulaziz City for Science and Technology, Saudi Arabia
W
ater vapor is the most important greenhouse gas. It plays a major role in the dynamics of atmospheric circulation,
radiation exchange within the atmosphere and climate variability. In this study, radiosonde data from 1985 to 2014
were used to examine the variaability of the precipitable water vapor (PWV) in central Saudi Arabia in the city of Riyadh (24
0
43 'N; 46
0
40'E, 764 m a. s. l.) over different time scales. The results revealed a clear seasonal cycle of PWV with a maximum
during the summer months (June to August) and a minimum during the winter (December to February). This variation
follows the mean monthly variation of air temperature. The PWV displays considerable variability at the inter-annual scale.
We could not attribute the variations to the air temperature because no relationship was found between the two variables when
the inter-annual variations were examined. Study of the annual variations of the PWV showed cyclic variations with a period
of approximately 10 to 11 years. The two maximums and minimums were in 1996 and 2007 and 1989 and 2000, respectively.
The results showed that the annual PWV values are anti-correlated with solar activity, represented by sunspot number, during
solar cycles 22 and 23. The physical mechanism underlying this relationship remains unclear, in which future investigations
are recommended.
amaghrabi@kacst.edu.saJ Earth Sci Clim Change 2016, 7:9(Suppl)
http://dx.doi.org/10.4172/2157-7617.C1.028An assessment of low flow and drought characteristics in the Barlad River catchment area
Silvia Mihaela Chelcea
National Institute of Hydrology and Water Management, Romania
T
he aim of this study is to assess and to analyze the seasonal and interannual variability of the low flow indices in the
Barlad River catchment area. The low flows and droughts have an important role in the river flow regime because they are
significantly connected with the basic water resources. This analyse might provide an efficient management of the resources
during the hydrological extremes, as well as an assistance in prevention and risk management strategies. The study is based on
the use of the software package LFSTAT that enables the standardized calculation of low flow statistics, in order to provide the
low flow indices. The times series of daily discharges at the nine hydrometric stations situated in the Barlad River catchment
area for the period 1970-2014 have been used for this analysis. Also, the calculation was made for a hydrological year beginning
from December 1st to November 30th. A stream-flow deficit analysis was performed using the threshold level method, where
the 70th percentile from the duration curve was used as the threshold level. Based on this analysis of the low flow and drought
characteristics, an assessment of the stream-flow deficit in the Barlad River Basin was highlighted.
silvia_chelcea@yahoo.com