Detalles de publicación
PP 08038
Sunshine and synoptic cloud observations at Ebro Observatory, 1910–2006
(1) Observatori de l’Ebre, CSIC - Universitat Ram´on Llull, Spain
(2) Instituto de Astrof´ısica de Canarias, La Laguna, E38200, Spain
ABSTRACT: The aim of this study is to characterize the evolution of the number of bright sunshine hours and cloudiness
at Ebro Observatory. Sunshine and synoptic cloud observations, extending over almost a century, are available from the
Ebro Observatory in the north–east of Spain. Here, we analyse these time series and find a strong decadal variability in
the duration of bright sunshine hours since 1910, but without a statistically significant long-term trend. A comparison with
sunshine records from other Spanish Mediterranean observatories was also performed to validate the Ebro time series over
the shorter time interval for which comparison stations are available. At the same time, we find a monotonic increase in
synoptic cloud amount since the 1920s. Time series of cloudiness at different heights are also available at Ebro in digital
form dating from 1954, and their analysis allows us to interpret these results as a change in cloud type frequency, possibly
coupled with changes in air transparency. Copyright  2008 Royal Meteorological Society
at Ebro Observatory. Sunshine and synoptic cloud observations, extending over almost a century, are available from the
Ebro Observatory in the north–east of Spain. Here, we analyse these time series and find a strong decadal variability in
the duration of bright sunshine hours since 1910, but without a statistically significant long-term trend. A comparison with
sunshine records from other Spanish Mediterranean observatories was also performed to validate the Ebro time series over
the shorter time interval for which comparison stations are available. At the same time, we find a monotonic increase in
synoptic cloud amount since the 1920s. Time series of cloudiness at different heights are also available at Ebro in digital
form dating from 1954, and their analysis allows us to interpret these results as a change in cloud type frequency, possibly
coupled with changes in air transparency. Copyright  2008 Royal Meteorological Society