Please login first
A lagrangian analysis of the moisture transport during the 2003 drought episode over the Mediterranean region
* , , ,
1  Environmental Physics Laboratory (EPhysLab), Facultade de Ciencias, Universidad de Vigo, Ourense 32004, Spain


In the last decades many studies have pointed out an increasing number of natural hazards associated with extremes in precipitation and drought conditions. Generally, dry and hot conditions across the Europe impact on the Mediterranean region. The Mediterranean is located at the border between the tropical climate zone and the mid latitude climate belt. Due to its large extension and diverse topography, it shows large climatic differences that make its climate scientifically interesting.  

The aim of this study is to analyze the moisture transport during the 2003 drought episode observed over the surroundings of the Mediterranean. The region was defined according to the 5th Intergovernmental Panel on Climate Change (IPCC) Assessment Report. The episode was identified using Standardized Precipitation Evapotranspiration Index (SPEI), calculated using monthly CRU (TS3.24.01) precipitation and potential evapotranspiration (PET). One of the crucial advantages of the SPEI over the other widely used drought indexes is its multi-scalar characteristics, which enable identification of different drought types. Therefore, the monthly SPEI-1, SPEI-3, SPEI-6, SPEI-12 and SPEI-24 indexes were used to identify the episodes on different time scales. This episode was the most severe during the period 1980-2015 according to the SPEI-1 analysis. Analyses of precipitation, potential evapotranspiration, omega at 500hPa, and vertically integrated moisture flux have been conducted to characterize the anomalous patterns over the region during the event. A Lagrangian approach was then applied in order to investigate possible changes in the moisture transport from and toward the Mediterranean region during the episode. This approach is based on the FLEXPART model integrated with the ERA-Interim data set.

Keywords: Drought, Mediterranean region, Lagrangian method, SPEI.
Comments on this paper
Rogert Sorí
Dear authors !

I consider it is an interesting paper and your approach like a new method to understand the causes and variability of drought episodes, not only in the Mediterranean region. I think it would be important in the future work to investigate/explain the atmospheric circulation mechanisms that could be responsible for moisture transport from the remote Gulf of Mexico and the western-tropical north Atlantic near the EEUU coasts.

Kind regards.
Milica Stojanovic
Dear Rogert,

Thank you so much for the sugestion. We will consider it in the future.

Kind regards,

Milica and Co-authors

Diego Miralles
Mediterranean Sea anomaly
Dear authors,

I read the contribution and found it very insightful. I believe there are many interesting ways of extending this analysis, and I am sure you are already thinking of some.

My question now is whether you have an idea of why the moisture advection from the Mediterranean Sea was so anomalously low, i.e. whether that related to an anomalous circulation and/or a low evaporation in this source. I wonder as well about the impact this anomaly may have had on the subsequent heatwave in central Europe, bearing in mind that the latter was very much affected by the antecedent rainfall scarcity in previous months...

Milica Stojanovic
Dear Diego,

Thank you very much for the comment. We will extend this analysis.
Moisture advection from the Mediterranean Sea can be related with the an anomalous anticyclonic circulation localized over Central Europe which inhibited the transport of moisture to the analized region. It does not seem related with evaporation, since there was an increase in evaporation during the period.

Among the extension analysis, we will look forward analysis from the region (MED-AR5) to
investigate possible changes in moisture transport from MED-AR5 during the drought.

Milica and Co-authors