Climate

The climate of the archipelago is conditioned by its geographical position (45 latitude), the layout of the surrounding mainland and by the influence of the sea.

More than a century ago, Ambroz Haracic (teacher, meteorologist and scientist from Mali Losinj, 1855-1916) studied the meteorological conditions of these islands and made detailed meteorological observations. His results and conclusions will be mentioned several times here. This chapter on climate is also based on Ambroz Haracic's studies.

Most of the sun's radiation reaches these latitudes in June, when days are longest. July is the period of highest soil and air temperatures; the highest sea temperatures are in August. The process is reversed during the darkest part of the year, when the days are shortest and nights longest. This is when we have the least amount of sun's radiation (December), followed by a period of lowest air and sea temperatures. This results in a month of relatively stable and constant air temperature during the period of winter and summer solstice. The transition from one season to the next brings greater changes of weather.

The influence of the sea with its great thermal capacity lessens the changes in temperature by decreasing the maximum temperatures and increasing the minimal ones. The same is true of both the daily and yearly changes of temperatures.

The sea is also a source of humidity. In the proximity of the shore on clear days the circulation of air is a result of the disparate speeds of heating of the sea and land. The resulting wind (mistral) blows from the sea landwards, especially on the westerly side of the island, where it brings a pleasant cooling of the air.

There are frequent cyclones in spring and autumn which, because of the configuration of the surrounding mainland, pass over the islands causing atmospheric currents, great changes of air masses and of the weather. The air masses which arrive here from the Mediterranean Sea are warm and humid and are the cause of mild weather and rain. The moving of cyclones eastward bring about the next chane, across the mainland from the north. Turbulent atmospheric processes take place on the borderlines of the air masses. The cyclone activity can first of all be recognized by the appearance of scattered, high clouds, followed by lower and darker cloutd, which move quickly northward. At the same time, on the front of the cyclone there is a strengthening of the southeastern wind, called "Levant", or the southern, called "Scirocco". The Scirocco is wind which gradually and evenly intensifies in force and causes high, long waves. In there conditions, the waves need practically a whole day to achieve their maximum size and force. After the sirocco there is usually a calming of the wind and the beginning of heavy rain, which indicates the approaching of the center of the cyclone. When the center of the cyclone moves off, there is a sudden shange of weather. The rain stops, the wind changes in direction and begins blowing from the north (the "Tramontana") or from the northeast (the "Bora"). In comparison to the sirocco, the bora gains in force very rapidly, sometimes even in only half an hour and therefore, can be a danger for boats, surfboards, etc. With the bora, the waves are smaller but stronger with a lot of spume, and during a Bora of hurricane force, clouds of sea drops, flying through the air, are not a rare phenomenon. This is why, in the spring, after strong winter bora winds, the vegetation, especially on the northern side of the islands, seems to have been burned. Another charachteristic of the bora is that it blows in gusts, that is, now stronger, now weaker, and generally strengthens as the day grows. it is weaker in the morning, the strongest during early afternoon hours, and weaker again towards the evening and during the night.

This progression usually lasts three to four days, even though there may be exceptions, depending on the size, speed and other particulars of the cyclone. The cyclone may pass more to the south of the islands, but is nevertheless manifested here by the arrival of the bora.

The mentioned changes of air masses have a favorable influence on life on these islands. During summer months, with the Alps to the north, and the Velebit mountain chain to the east, shelter the Kvarner Bay from bad weather conditions, so that the weather is sunny and stable.

Clouds will accumulate on the mainland as a result of cool air masses coming from the Atlantic. Since such air masses are usually low, it is hard for them to cross the Alps or Velebit, and so they are often not even felt on the islands. If it comes to brief showers and drops of temperature, only a few hours later the sun shines once again, and after that the air is particulrary clean and dry. As a result of such penetrations of cold air masses, the Bora sometimes blows very strongly in the Velebit Channel, while it is usually of a much lesser intensity on the island of Losinj.

We may conclude that the climate on these islands is of a moderately-warm, rainy, type, with warm and dry summers and rainy autumns, but without expressly dry periods. The northern part of the island of Cres belongs to the sub-Mediterranean zone, while its southern part and the island of Losinj, with all the other islands of this group are in the Mediterranean zone.

A climate with such features was favorable for the flourishing diverse vegetation. It is no wonder that man has also found a "paradise" for himself on these islands (B.Penzar, 1981). As far back as 1892, at the initiative of Austrian experts, the island of Losinj was proclaimed as climatic health resort.