Space weather user requirements of solar data

Space weather is an interdisciplinary field, especially from the scientific point-of-view and demands data from all parts of gee-space. Of utmost importance it requires constant monitoring of the Sun, relying on both space-borne and ground-based observations. The question of data handling in this respect requires a complex yet as simple as possible approach. In the above context, the requirements of solar data for space weather related issues will be addressed in this paper having the user in mind. Emphasis will be made on the point that the data centers must have a clear understanding of what the users actually need as information. This will be illustrated by showing examples of various space weather induced effects and looking at the physical phenomena that caused them. It shall be stressed that the time required to avoid these unwanted effects is an important factor in defining the type of solar data necessary to forecast the above phenomena. Hence a fundamental need is that better communication between the user and solar community must be aimed at.