النماذج الجغرافية للطقس في الوسط القاري للمملكة العربية السعودية : دراسة منهجية

الملخص EN

This paper aim to coining a new approach to be used in the identification of climate in Riyadh , by means of developing a original and new concept "Weather Geographical Types ".

Hence the approach is based on the delineation of weather types and behavior according to the geographical structure of the delineated type.

The study covers the period between 1985-2010 and uses the daily minimum maximum and mean temperature recorded during this period.

In addition to observations concerning daily wind speeds and atmospheric pressure conditions during the same period, many characteristics concerning the climate of the study area have been identified.

These include geographical as well as climatic folds of characteristics.

As for the first fold the continental factors appear to be dominating the nature of the area's climatic types.

These factors influence monthly temperature regimes which look similar particularly during the hot summer months.

As for the dynamic climatic characteristics characteristics identified in Riyadh area, some points could be mentioned .

Climatic types of western and southern structures are apparently less frequent, while those types of northern structures are more frequent and observable the year round.

This fact has shown the importance of the Arabian Thermal Low, which is regarded as a continuation of the seasonal Indian Low in Arabia.

The actual climatic behavior for all months has been portrayed with reasonable confidence.

In turn, the result allowed the research to geographically delineate the seasons.

The results facilitated the better understanding of monthly and annual internal variations that occur in the climatic structures of the study area , and this is considered as one of the main findings of this research