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During the CIESM workshop (Monaco, 22–24 April 2002) entitled “Monitoring Hydro- logical Trends in the Mediterranean”, the review of existing data sets and analyses has revealed important variability in the dynamics and hydrological characteristics, in the past century, ranging from interannual to decadal time scales. These variations are related mainly to local forcing and larger scale atmospheric parameters (NAO, ENSO, Indian monsoon). Moreover, abrupt events contribute to modification of the Mediter- ranean conveyor belt, also influencing the biogeochemical environment and the Mediter- ranean outflow in the Atlantic Ocean. The participating scientists have agreed on the need of a sustained multi-component long-term monitoring system based on both oceanographic and atmospheric observations and modelling. The group also proposed an expansion and strengthening of the ongoing relevant large operational programs by a “climatic approach” component.

Summary form only given. The propagation of electron beam generating solar type III bursts is considered at the distances much larger than the length of quasilinear relaxation. As it takes place in homogeneous plasma the electron beam being initially monoenergetic propagates as a beam-plasma structure that consists of electrons and Langmuir waves. Beam-plasma structure propagating in uniform plasma loses a part of the fastest and the slowest electrons that leads to its decay. The maximum of electron density and energy density of plasma waves propagates with constant velocity. The numerical simulations fulfilled show that the inhomogeneity with decreasing density at the scales larger than the relaxation length can increase the time of this structure existence in corona.

Summary form only given, as follows. The propagation of an electron stream is considered in the limit of weak turbulence when the quasilinear time is much smaller than the time of electron stream flying-off. It is found out that the initial electron distribution function of the electron stream propagating in plasma is unstable to decay into separate beams. Langmuir waves excited by the fast beams accelerate electrons of slow beams that leads to interaction between them: the number of particles in the fast beams increases and their phases change. The electron distribution function and spectral energy density of plasma oscillation are found by gas-dynamic approximation.