Current distribution of wind in Morocco

Abstract

Information about wind is widely used in many sectors of the economy. Wind also causes many dangerous and extreme weather events. Modern climate changes require a certain revision of weather patterns previously accepted for the area. This article provides information on the current space and time distribution of wind characteristics within the territory of Morocco. During the period of 2005-2014 some monthly average wind speed values and data on repeatability of wind directions by gradations were obtained on the basis of physical and statistical analysis of results of observations of wind speed and directions performed at 26 stations. The authors defined the character of distribution of monthly averages of wind speed within the territory and its seasonal changes. Most of the territory is covered by mountains of Morocco which encourages development of local winds. At central and northern regions of Morocco predominance of weak winds due to complex orography of terrain is observed. In the central part of Morocco there is a region with the lowest values of wind speed. Formation of the wind regime at the coastal stations takes place in a developed breeze circulation. Wind speed and direction are significantly different at the nearby stations, such as Larache and Chefchaouen, Meknes and Fez. Increase of wind during the warmer half of a year was revealed at all stations. Nature of annual variation of average wind speed at the stations allows us to split the stations into two groups. The first group includes the stations where the average wind speed increases in summer and decreases in winter. The second group includes the stations where the average wind speed increases in spring and decreases in autumn. In the southern part and along the coast, where the terrain is flat, an increase of wind speed is observed. On open plains of the southern part of Atlantic coast during all seasons wind has a direction corresponding to direction of trade winds of the Northern hemisphere. It should be noted that the main factor forming air circulation within the territory of Morocco is represented by trade winds the intensity of which nearly doubles from summer to winter. Formation of wind directions at the stations takes place mainly under the influence of terrain of the area. At many stations predominant wind direction in January changes by 180º in comparison to the respective July values. Therefore, characteristics of the wind regime of Morocco in 2005-2014 consist in increase of wind speed in the coastal zone and decrease thereof in mountain areas together with presence of two types of annual variation of wind speed depending on physical and geographical conditions.

Keywords

• wind speed and direction, wind regime of Morocco, seasonal changes of wind characteristics, space and time distribution of wind in Morocco