Investigating the Consequences of Climate Change with a Focus on Spatial analysis of drought severity in Golestan Province using Statistical and Remote sensing indices

Document Type : Original Article


Faculty of geography, University of Tehran, Tehran, Iran


Drought is one of climate hazards that over time brings a lot of damage on human life and natural ecosystems. Commonly Droughts are divided to four main groups of meteorological, hydrologic, agricultural and socio-economic .All Types of droughts are different from each other significantly. In another sense, the occurrence of an event of drought would be the cause of another draught. Various methods have been used for the analysis and assessment of drought and its impacts on human activities and natural resources. Statistics, Synoptic, Remotely sensed methods, and several types of models such spatial, dynamic and statistics models can be seen in the most studies related to drought. The zoning of drought using spatial-statistics indices and generally the spatial zoning and regional distribution of dry periods is one of important features that makes a better understanding towards the phenomenon of drought and a closer consideration of the effects of it. In the past four decades remote sensing widely provide drought monitoring tools, and many drought monitoring model is presented, which is generally based on vegetation and thermal indices especially Normalized Difference Vegetation Index (NDVI), land surface temperature (LST), moisture and reflection at the visible and infrared areas.
Golestan province is located in the North East of Iran in the neighborhood of the Caspian Sea and the northern slopes of the Alborz Mountains, Which following local conditions of the Caspian coast line and high peaks, with increasing altitude, vegetation diversity there are certain bands. From the peaks over 1500 meters to foothills is covered with dense forest broadleaf. Field craps are the dominant vegetation’s From Foothills to the plain. From North Gorganrood to border of Turkmenistan due to rare moisture Resources vegetation is thinner than the southern and central provinces.
The research in terms of nature and methods in theoretical basis is parts of the descriptive researches and due to relationship and impact is an applied one. In the present study for following meteorological drought and ecological in Golestan province, two types of data were used. 72 pluviometry stations on monthly rainfall data (period 1971-2010) and remote sensing data in the three periods (July, 1975, 1987 and 2000), derived from Landsat satellite images. Standard Precipitation Index (SPI) is used to identify and to zoning meteorological drought and the Normalized Difference Vegetation Index (NDVI) is used for the detection of the plant tension that were affected by drought. In the following the results of two parameters and their relationships were compared to each other.
 Examining maps of drought frequency and severity of droughts indicates that most of frequency droughts of stations occurred in the North and North-East Province. And gradually the intensity and frequency of droughts reduced to the South and South West. The most severe drought that can be seen in parts of the North East belongs to the Hutan station. However the lowest number has occurred in the central and western regions of Golestan province. According to table (3) correlation between both NDVI and SPI are positive in three years. In all the years of study SPI index-correlation with NDVI was fairly good together. Overall the parts of Northern Province and East Sea have most drough in the selected three years. While most of the wet years are related to the southern part of the province (northern slopes of the Alborz mountain range).
 According to conducted research either in the country or abroad, it seems that the use of SPI index as representative of meteorological drought and NDVI index as representative of indicators satellite drought are appropriate for monitoring this kind of droughts. According to the study, two SPI drought index and NDVI due to adaptation with each other are proposed for drought monitoring and meteorological satellite in Golestan province.


  1. منابع

    1. انصاری، حسین. و داوری، کامران. 1386. پهنه­بندی دوره خشک با استفاده از شاخص بارندگی استاندارد شده در محیطGIS ، مطالعه موردی: استان خراسان، پژوهش های جغرافیایی، شماره 60، 97-108.
    2. باعقیده، محمد. علیجانی، بهلول. ضیائیان، پرویز. 1389. بررسی امکان استفاده از شاخص NDVI در تحلیل خشکسالی های استان اصفهان، مطالعات جغرافیایی مناطق خشک، شماره 4، 16-1.
    3. بذرافشان، جواد. ابراهیم زاده، سجاد. قربانی، خلیل. 1392. امکان سنجی تشخیص تغییرات پوشش گیاهی مبتنی بر شاخص های زمینی و ماهواره ای خشکسالی (مطالعه موردی: استان کرمانشاه)، مجله هواشناسی کشاورزی،  شماره 1، 48-37.
    4. پرویز، لاله. خلقی، محمدرضا. ولیزاده کامران، خلیل. 1388. پایش خشکسالی با استفاده از شاخص پوشش گیاهی و دمای سطح زمین حاصل از تصاویر ماهواره ای Terra-MODIS، چهارمین کنفرانس سراسری آبخیزداری و مدیریت منابع آب و خاک، آذر 1388، کرمان: 1081-1073.
    5. جهانبخش اصل، سعید. ساری صراف، بهروز. خورشید دوست، علی محمد. رستم زاده، هاشم. 1388. ارزیابی تغییرات پوشش گیاهی دشت سراب و تحلیل دو دوره ی خشکسالی و ترسالی، فصلنامه علمی-پژوهشی انجمن جغرافیای ایران، شماره  23، 132-117.
    6. حجازی­زاده زهرا و جوی­زاده سعید. 2007. نرم­افزار Drought Indices Calculator (DIC), Ver. 1.0 Beta
    7. خواجه، فاطمه. 1386. پایش خشکسالی با استفاده از شاخص اختلاف پوشش گیاهی نرمال شده (NDVI) در استان اصفهان، پایان کارشناسی ارشد، دانشگاه اصفهان.
    8. رحیم زاده، پریناز. 1384. بررسی امکان استفاده از تصاویر NOAA-AVHRR برای پایش خشکسالی، پایان کارشناسی ارشد، دانشگاه تهران، دانشکده محیط زیست.
    9. رضایی مقدم، محمدحسین. ولیزاده کامران، خلیل؛ رستم زاده، هاشم. رضایی، علی. 1391. ارزیابی کارایی داده های سنجنده ی MODIS در برآورد خشکسالی حوضه ی آبخیز دریاچه ارومیه، جغرافیا و پایداری محیط، شماره  5، 52-37.

    10.شاهیان، رامین. جامع، عبدالکریم. آریانفر، رامین. حقیقت، مسعود. و دهقان، حیدر. 1388. پهنه­بندی آستانه بحران خشکسالی استان فارس با کاربرد شاخص معیار بارش SPI و GIS مجله مهندسی منابع آب، شماره ۲، 42-33.

    11.شمسی‌پور، علی‌اکبر. 1386. تحلیل خشکسالی با استفاده از داده های سنجش از دور در منطقه کاشان، رساله دکتری، دانشگاه تهران.

    12.شمسی‌پور، علی اکبر. علوی پناه، سیدکاظم. محمدی، حسین. 1389. بررسی کارایی شاخص های گیاهی و حرارتی ماهواره NOAA-AVHRR در تحلیل خشکسالی های منطقه کاشان، فصلنامه ی علمی-پژوهشی تحقیقات مرتع و بیابان ایران، شماره 3، 465-445.

    13.محمدیان، آزاده. کوهی، منصوره. آدینه­بیگی، آرمان. رسولی، جواد. بذرافشان، بهاره. 1389. مقایسه پایش خشکسالی با استفاده از SPI، PNI، DI و پهنه بندی آنها (مطالعه موردی: استان خراسان شمالی)، مجله پژوهش­های حفاظت آب و خاک، ، شماره 1، 184-177.

    14.Bhuiyan, C., Singh, R.P. and Kogan, F.N. 2006. Monitoring drought dynamics in the Aravalli region (India) using different indices based on ground and remote sensing data, International Journal of Applied Earth Observation and Geoinformation, 8: 289-302.

    15.Funk, C. and Budde, M.E. 2009. Phenologically-tuned MODIS NDVI-based Production anomaly estimates for Zimbabwe, Remote Sennsing of Environment, 113: 115-125.

    16.Heim, R.R. 2002. A Review of Twentieth-century Drought Indices Used in United States Bulletin of the American Meteorological Society, 84: 1149-1165.

    17.Ji, L. and Peters, A. 2003. Assessing vegetation response to drought in the northern Great Plains using vegetation and drought indices, Remote Sensing of Environment, 87: 85-98.

    18.Jurgen, V., Vogat, Alain A., Viau, Isabelle, Beaudin, Stefan Niemeyer, Francesca Somma. 23-27 Nov 1998. “Drpught Monitoring From Space Using Empirical Indeces and Physical Indicators”, Proceedings International Symposium on Satellite-Based observation, Tunis, Tunisia.

    19.Kogan, F.N. 1995. Application of vegetation and brightness temperature for drought dete Advances in Space Research, 11: 91-100.

    20.Quiring, S.M. and Ganesh, S. 2009. Evaluating the utility of the Vegetation Condition Index (VCI) for monitoring meteorological drought in Texas, Agricultural and forest meteorology, 150: 330-339.

    21.Tucker, C.J. 1979. Red and Photographic Infrared Linear Combinations for Monitoring Vegetation, Remote Sensing of Environment 8: 127-150.

    22.Thenkabail, P.S., Gamage, M.S.D.N. and Samakhtin, V.U. 2002. Evaluation of Narrowband and Broadband Vegetation Indices for Determining Optimal Hyperspectral Wavebands for Agricultural Crop Characterization, Photogrammetric Engineering and Remote Sensing, 68: 607-621.

    23.Wang, P., Li, X., Gong, J. and Song, C. 2001. Vegetaion Temperature Condition Index and it application for drought monitoring. Internationa Geoscience and Remote Sensing Symposium (Sydney, Australia).

    1. Wilhite, D.A. 2000. Drought as a natural hazard. In D.A. Wilhite (Ed.), Drought. A Global Assessment, Vol. I (pp. 1-18). London: Routledge.