We all share this Mediterranean Sea. But we must be able to preserve and protect this valuable heritage, to keep it secure and make it prosperous. This can only be a collective achievement, for it is true that no country can enjoy lasting development and security at the expense of another country's security. The Mediterranean weather is characterized by windy, mild, wet winters and relatively calm, hot, dry summers. Spring, however, is a transitional season and is changeable.
Autumn is relatively short.
The amount and distribution of rainfall in the Mediterranean cannot be generalized. Because the primary productivity of life forms depends to a large extent on the concentration of the plant nutrient salts, it is, as would be expected, generally low in the Mediterranean Sea. The environmental conditions of the Mediterranean already described, namely, the low concentration of phosphates and nitrates so necessary for the maintenance of marine pastures, together with the poor standing crop of bottom-dwelling organisms, provide no opportunity for the evolution of a big fishing industry. The fish fauna of the Mediterranean is basically related to fauna of subtropical Atlantic with a large variety of species. Sardines constitute the main catch in the western and northeastern parts of the Mediterranean.