Geofizika, Vol. 25 No. 1, 2008.
Kratko priopćenje
Analysis of rainfall records (1923–2004) in Atar-Mauritania
A. Ould Cherif Ahmed
H. Yasuda
K. Hattori
R. Nagasawa
Sažetak
The shortage of water resources in Adrar region, especially in Atar (Capital
city of Adrar prefecture) and the surrounding villages along Seguelli watershed
has been taken the concern of the policy maker and populations of
this region since long time. This area had been suffering from recurrent
droughts and faced water crises many times. Several attempts have been
made to overcome these problems. Meanwhile the risk is still endangering the
life and agricultural activities in one of the most important oasis areas. This
study analyzed Atar rainfall time series periodicity, trends, and its relationship
with Sea Surface Temperature (SST). The nonparametric Spearman test
was used for trend analysis and the serial autocorrelation for persistency.
Also, power spectrum and Fourier fit were deployed for analysis of frequency
and periodicity. The tendency of Atar rainfall time series shows rainy periods
in 1920’s and 1950’s and decreased rainfall since the late of 1950s. On the
other hand, the prolonged drought periods appeared during 1970’s in contemporaneous
with the Sahelian drought. The persistency analysis indicated the
presence of biennial components in the annual and bimonthly rainfall in last
three decades. SSTs of Atlantic, Indian and Pacific Ocean were modulating
Atar rainfall during 1923–1992 period.
Ključne riječi
Atar-Mauritania; frequency; persistence; rainfall; SST; trend
Hrčak ID:
25450
URI
Datum izdavanja:
1.7.2008.
Posjeta: 1.110 *