Precipitation climatology over the Mediterranean Basin — Validation over Cyprus

• A study comparing TRMM and E-OBS data is performed over the Mediterranean.
• In situ measurements from Cyprus are compared with E-OBS and TRMM data.
• It was found that TRMM and E-OBS data are highly correlated over Cyprus.
• Both TRMM and E-OBS data are highly correlated with rain gauge data over Cyprus
• The effect of altitude on both E-OBS and TRMM produces a generally high variation.

A study for a 15-year period (1998–2012) embracing both satellite and rain gauge data is performed over the Mediterranean basin. Tropical Rainfall Measuring Mission (TRMM) 3B43 monthly data (versions 7 and 7A) are compared with the corresponding E-OBS gridded rain gauge precipitation data over a common 0.25 × 0.25° grid. The study focuses over Cyprus, where a dense and reliable network of rain gauges is available. These in situ measurements are compared with both E-OBS and TRMM data for the aforementioned 15-year period. Monthly and (seasonal) yearly comparisons are presented for each of the 0.25 × 0.25° cells overlaying the island of Cyprus. For each of these cells, at least three rain gauges are sited within its corresponding area. BIAS and mean absolute error (MAE) for TRMM and E-OBS estimates from the corresponding averaged gauge data were extracted. The results show a very good correlation (as high as 0.95) over areas where TRMM data incorporate rain gauge measurements along with satellite data. However, the poor correlation over other areas (as low as 0.05) is of great interest and needs to be studied further. The overall conclusion from this study is that TRMM and E-OBS estimates are well fitted with the gauge data, although they are both influenced by the variation of elevation.