We are facing a space with peculiar climatic conditions, vegetation and fauna. These factors are conditioned by the fact that it is a great plain surrounded by the sea. In it we find climatic conditions characterized by low thermal fluctuation, with mild temperatures and high humidity.
The scarce and irregular rainfall is almost always accompanied by the fresh and humid east wind, which causes these often stormy rains. Throughout the year we find periods with rains: from September to November and from April to June; and dry periods: from December to March and from July to August.
Average temperatures vary between 26ºC in July and August, and up to 10ºC in January. The maximums and minimums oscillate between 39ºC and -6ºC, although the presence of temperatures below zero is rare.
The situation of the winds is very marked by the presence of the gale or wind from above. This northwesterly wind is channeled along the mountainous valleys of the Ebro Depression, causing strong winds, of a dry and temperate nature, of great incidence especially in the months of November to April.
The rest of the year is characterized by the presence of marinades, soft and humid breezes from sea to land, and the main cause of the rains in the Delta.
In any case, the climate is never a limiting factor for the development of the different species of mosquitoes. Average temperatures above 20 ºC accompanied by high relative humidity are the key to good larval development.
The main winds of the summer period are the marinades, winds from sea to land, which favor the dispersal of the adults of Ochlerotatus caspius, mosquitoes developed on the coastline, but which at certain times, favored by these winds, we can notice their presence on land inside, even in points of the Montsià massif.
