تحلیل‎های فضایی در تولید نقشۀ پهنه‎بندی اقلیمی (مطالعۀ موردی: منطقۀ غرب دریاچۀ ارومیه)

نوع مقاله: مقاله کامل

نویسنده

استادیار گروه علمی دانشگاه پیام نور، تهران، ایران

چکیده

مسائل جدی زیست‎محیطی و گستردگی و پیچیدگی‎های امروزی روابط متقابل انسان و اقلیم در ابعاد متفاوت زمانی ـ مکانی، ضرورت مطالعه و تهیۀ نقشۀ پهنه‎های اقلیمی را که ابزار توسعۀ پایدار شمرده می‎شوند، روشن می‎کند. مناطق مختلف طبیعی و زیست‎محیطی دارای تیپ‎های اقلیمی متفاوتی هستند. در همین ارتباط بسیاری از نواحی کشورمان، به‎ویژه در منطقه‎ای که برای این پژوهش در نظر گرفته شده، تیپ‎های اقلیمی هنوز مشخص و مطالعه نشده‎اند. تعیین تیپ‎های اقلیمی منطقۀ غرب دریاچۀ ارومیه با استفاده از روش‎های تحلیل فضایی چندمتغیره، مانند MLC و DataISO و همچنین تحلیل چندمتغیره، مانند تحلیل عاملی و خوشه‎بندی، هدف پژوهش حاضر است. با توجه به اینکه عوامل و عناصر سازندۀ اقلیم از نظر ماهیتی متفاوتند، برای پردازش همزمان چنین داده‎هایی، تحلیل‎های فضایی ابزار قدرتمندی شمرده می‎شوند. به همین دلیل در این پژوهش داده‎های مربوط به عناصر و عوامل سازندۀ اقلیم منطقۀ ایستگاه‎های ارومیه، نقده، سلماس، اشنویه و کهریز و همچنین، ارتفاع و جهات جغرافیایی در تولید نقشۀ تیپ‎های اقلیمی به‎کار گرفته شده است. نتایج حاصل از این پژوهش نشان می‎دهد که چهار نوع اقلیم متفاوتِ سرد کوهستانی، مرطوب، نیمه‎مرطوب و نیمه‎خشک، در منطقۀ غرب دریاچۀ ارومیه حاکمیت دارند.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Spatial Analysis for Production of Climate Classification Maps, West Part of Urmia Lake

نویسنده [English]

  • Ali Nasiri
Assistant Prof., Dep. of Geography, Payamnoor University, Tehran, Iran
چکیده [English]

Introduction
In the modern era of communication, by increasing population the resources would be relatively
scarce. Therefore, in order to deal with environmental serious problems and complex humanclimate
relationship in all dimensions of spatiotemporal and land use planning and programming
practices, the climatic zone map was a sustainable developmental tool in the study area.
Methodology
The climate zones are recognized by investigating the analysis of various climatic factors,
different empirical methods and spatial and nonspatial quantitative methods. The natural
environmental areas have differential climate zones. Accordingly, different climate zones of
Iran especially climate factors and local variables are neither studied nor recognized. Hence, the
main purpose of the present study is to produce climate zones map of west part of Urmia Lake
by the simultaneous analysis of spatial and nonspatial climate data. West area of Lake Urmia is
studied in the present paper as a region of environmental problems; it is the main part of Urmia
Township that contains Urmia city. This is the largest and capital city of West Azerbaijan
Province. Various climate factors whether of local or global influences affect formation of
climate types in the area. Inherent factors are (or genetical) global wind systems like westerlies,
polar cell systems and complex local natural circumstances, vegetation cover, superficial water
resources, elevation, geomorphology and topographic conditions, geographical directions, and
geographical latitude and longitude. Climate producer factors have different properties.
Accordingly, analyses of the obtained data are very difficult, so the spatial analysis methods are

proposed as powerful tools for simultaneous analysis of the different data. In this research,
diverse climate data and factors from various resources in different stations of the studied area
such as Urmia, Naghadeh, Salmas, Oshnavieyeh, and kahriz together with height and
geographical directions data have been analyzed to produce map of different climate zone.
Hereby, analysis of different types of data such as spatial and nonspatial data is one of the most
difficult challenges in climatic researches. In order to solve this challenge, GIS spatial analysis
techniques, spatial and multivariate analysis algorithms such as Maximum Likelihood analysis
(MLS), Principal Component Analysis (PCA) and Iterative Self Organizing Data Analysis
Technique (ISO data) have been used to analyze different types of data. Structure of variables
has been verified by application of the multivariate analysis of PCA method. The number and
nature of the factors have also been analyzed to specify the rate and find out how they are
affected by climate properties of the study area. By using PCA methods the effective factors
have been employed to determine contribution rate of each factor in development of climate
area.
Results and Discussion
The results show that there are 4 different climate types: mountainous cold, wet, semi – wet and
semi – arid climates in the west part of Urmia Lake area. It is also shown that the local factors
(such as height, geomorphologic features including aspect, slope, spatial arrangement of
mountains and etc. under the control of external factors such as west, north and southwest wind
systems entering into the area, play an important role in the formation of climate types. They
also act as a reinforcement or adjustment of climatic conditions. Here, in survey of the present
study, the term of named as morpho–climatic subject is as a new phase in studies of
climatology.
Conclusion
Investigation of the results shows that the local condition and factors like geomorphology and
topographic characteristics of a region in different scales under the control of external factors
such as west, north and southwest wind systems play an important role in development of
different climate types such as different patterns of the micro regional and local climates. This
can be concluded that climate properties are developed by the influence of both geomorphologic
and weather conditions of a specific region.

کلیدواژه‌ها [English]

  • Climate Zonation
  • ISO Data
  • Maximum Likelihood Classification
  • Spatial analysis
  • Urmia Lake