Moisture transport from its sources to surrounding continents is one of the most relevant topics in hydrology, and its role in extreme events is crucial for understanding several processes such as intense precipitation and flooding. In this study, we considered the Mediterranean Sea as the main water source and estimated its contribution to the monthly climatological and extreme precipitation events over the surrounding continental areas. To assess the effect of the Mediterranean Sea on precipitation, we used the Multi-Source Weighted-Ensemble Precipitation (MSWEP) database to characterize precipitation. The Lagrangian dispersion model known as FLEXPART was used to estimate the moisture contribution of this source. This contribution was estimated by tracking particles that leave the Mediterranean basin monthly and then calculating water loss (E − P < 0) over the continental region, which was modelled by FLEXPART. The analysis was conducted using data from 1980 to 2015 with a spatial resolution of 0.25°. The results showed that, in general, the spatial pattern of the Mediterranean source’s contribution to precipitation, unlike climatology, is similar during extreme precipitation years in the regions under study. However, while the Mediterranean Sea is usually not an important source of climatological precipitation for some European regions, it is a significant source during extreme precipitation years.

Moisture sources identification and Sea Ice Concentration (SIC) were calculated for the period 1980-2016 for the Southern Ocean Sea. Five sectors of the Southern Ocean Sea (King Hakon VII, East Antarctic, Ross/Amundsen, Amundsen and Bellingshausen, Weddell) were selected to calculate their moisture sources. The results show that the most important moisture sources (calculated as positive values of Evaporation minus Precipitation, E-P>0) for these five seas come from extratropical latitudes in the storm track trajectories. The main moisture sources and affected regional seas are: Southern Australia (SAUS) moisture source which affect mainly Ross/Amundsen and Amundsen and Bellingshausen seas; the Atlantic Ocean is the main source of moisture for Weddell and King Hakon VII; and the Pacific Ocean provides moisture to Ross/Amundsen, Weddell and Amundsen and Bellingshausen seas. For most of these seas it was identified positive trends of E-P>0 anomalies, while negative trends were identified only for the SAUS moisture source to Amundsen and Bellingshausen Sea. In terms of SIC, for the whole Antarctic the total anomalies are increasing, but no breaking points in this time serie were detected. Preliminary results also indicate some areas, which do not coincide exactly with the limit of the regional seas, where the increase of Sea Ice Extension (SIE) is statistically significant.

The moisture transport from its sources to the continents is one of the most relevant topics in the hydrology, and its role in extremes events is crucial to understand several processes in the Earth, as intense precipitations and/or flooding. Using the global precipitation (P) dataset from the Multi-Source Weighted-Ensemble Precipitation (MSWEP) from 1980 to 2015 with a 3-hourly temporal and 0.25° spatial resolution, a monthly precipitation climatology were done over the area of the Mediterranean Sea, checking grid by grid which year exhibits the maximum precipitation. As is well known, the Mediterranean Basin is a clear source of moisture for the surrounding areas. To link this source of moisture with the precipitation, in this work we have made use of the Lagrangian dispersion model FLEXPART to track, in its forward mode, those particles that monthly leave the Mediterranean Basin and we have calculated the loss of moisture (E-P<0) modelled by FLEXPART (P-FLEX) over the continental region. The aim of this study is to calculate the monthly climatological percentage of the Mediterranean contribution grid by grid, and the changes of this contribution for extreme monthly precipitation checking the importance of this sea source of moisture during the maximum peak of precipitation.