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Non-Uniform and Discontinuous Warming in the Area of the Eastern Mediterranean
Reference
Hasanean, H.M.  2001.  Fluctuations of surface air temperature in the Eastern Mediterranean.  Theoretical and Applied Climatology 68: 75-87.

What was done
The author investigated surface air temperature trends with data obtained from meteorological stations located in eight Eastern Mediterranean cities: Malta, Athens, Tripoli, Alexandria, Amman, Beirut, Jerusalem and Latakia.  The period of analysis varied from station to station according to available data.  Malta had the longest temperature record (1853-1991), while Latakia had the shortest (1952-1991).

What was learned
Of the eight temperature histories, four exhibited overall warming trends and four exhibited cooling trends.  Inter-decadal variations of various periodicities, however, were noted in the temperature records at all stations.  Also noted by the author was the presence of an "important warming around 1910," which began nearly simultaneously at all of the longer-record stations.  A second large warming was noted in the 1970s; but it was "not uniform, continuous or of the same order" as the warming that began about 1910, nor was it evident in all the stations.

What it means
An important observation to come out of the study was the fact that all of the stations exhibited similar uniform warming trends that began about 1910, but that only some of them exhibited a less coherent and discontinuous warming trend in the 1970s.  One reason for these two contrasting sets of behavior is that the warming observed at the turn of the century is most likely indicative of a true regional, if not global, phenomenon (perhaps solar-induced), as it was observed at all stations; while the warming observed at some stations in the later part of the 20th century is not a true global phenomenon.  A possible explanation for the different warmings of those cities that experienced temperature increases in the 1970s may be differences in city urbanization histories and patterns, which could have resulted in uniquely expressed urban heat island development at each measurement site.  These local phenomena must be fully understood before data from such sites are used to construct global temperature trends.