*3.1. In-Situ Rain Data*

The in-situ meteorological stations of the very reliable [30] dense and well-distributed network operated by the Cyprus Department of Meteorology were used for ground validation. Daily and hourly complete data records from 136 rain gauges were used for the study period (see Figure 1). These gauges are distributed in such a way so as to cover the whole study area, including not only coastal, urban and agricultural areas, but also the hilly and mountainous areas. It is worth noting that data underwent quality control prior to the present analysis.

The average annual total precipitation increases up the southwestern windward slopes from 450 mm to nearly 1100 mm at the top of the central massif. On the leeward slopes amounts decrease steadily northwards and eastwards to between 300 and 350 mm in the central plain and the flat southeastern parts of the island [34].

The annual average rainfall, covering the period 1951–1980, is 480 mm, exhibiting a decreasing trend in the last 30 years [34]. Furthermore, rainfall in the warmer months contributes little or nothing to the annual precipitation amounts.

It should be noted at this point that data from four meteorological stations are provided by the Cyprus Department of Meteorology to be incorporated in the TRMM and GPM estimates. These four stations are not representative of the country as a whole. Furthermore, they barely make up 3% of the data used herein, hence, the are not expected to have an impact on the objectivity of the study.
