Journal of Spatial Analysis

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Classifying daily climate circulation patterns has always been considered by climatologists. Investigating climate changes such as rainfall and the temperature in a same single time and place suggests that these changes are strongly influenced by atmospheric circulation patterns.

Regarding so, climate changes, known as variables here, such as rainfall, temperature, and other related phenomena, which are exemplified as flood, drought, glacial, and etc. are associated with special types of climate circulation patterns. The continuity and alternation of the systems are classified or identified climatically, therefore weather classification system is one of the main objectives of the synoptic climatology (Huth, 1996). Since every weather type creates its own special environmental condition, lack of identification in weather type frequencies leads to a difficult environmental explanation and alternation (Alijani, 1380: 64).

Identifying atmospheric circulation patterns different things that can be expressed inductively such as frequency, intensity, and spatial distribution of climate changes in rainfall and its physical causers (VicenteSerrano and LopezMoreno, 2006).

Heavy rainfall in many watersheds, particularly in the basin and sub-basin which involve less time exposure, causes floods and it also damages human, natural resources, infrastructure utilities and equipment. Before the occurrence of this kind of rainfall, it requires a deep understanding of the synoptic systems of their creator. This understanding is only possible through the classification and identification of rainfall patterns which used to cause floods in the studied basins.

The present study also aims at identifying and classifying the synoptic patterns of rainfall during the statistical stage of the study in the basin which caused flood in Taleqhan basin.

Taleqhan basin with area of (65/1242) per square kilometers is located in "36֯, 5', 20" to "36֯, 21', 30" north latitude and "50֯, 36', 26" to eastern longitude "51֯, 10', 18".

The study area is 120 kilometers away from North West of Tehran and located in a relatively high mountainous area in Alborz Mountain. This area is ranging from 1700 meters to 4400 meters above sea level. Average rainfall in this basin ara is 515/16 mm and its annual temperature fits 10.5 centigrade.  About 79 percent of rainfalls occurs from the cold weather period in November to March. It is also know as semi-humid cold weather based on the De Martonne classification.

Circulation algorithm (CA) and pattern clustering algorithm (PCA) were determined based on the daily methods in synoptic scale by applying information from stations in Taleqhan basin (Gateh deh, Dehdar, Dizan, Snkranchal, armouth, Ange, Joostan, Zidasht). In order to classify the weather type, daily average rate of 500 HPa and the sea level pressure (SLP) were extracted and reconstructed over the period (1980-2011) at the 2.5 degree of NCEP. Selected range includes 608 points from latitude of 10 to the 60 of northern degree, and latitude of 10 to 80 of eastern degree.

Principal components method mixes the interrelated points and reduces the matrix size, so 13 main components are remained that they includes 93 percent of the total variance. This study employs S array and Varimax rotation to identify different types of weather. It also makes use of K-Means clustering method to classify daily weather types. And finally, a matrix was formed in 118×608 dimension for 118 common days of rainfall among stations. All days were divided into four groups. They offer the most common climate circulation patterns in the proposed area. At the end, and finally integrated maps of sea level pressure and 500 HPa were drawn for each weather type. 

According to the results from factor analysis, 13 main elements were selected that they included 93% of the total variance of the data. According to the above mentioned method, all days (118 days) during the statistical period (1980-2011) were divided into 4 groups which provide the most climate circulation patterns in the study area. Then, integrated maps of sea level pressure and 500 HPa range were drawn for each of the types. Clusters were numbered according to the K-Means arrangement, and they were named based on the pressure patterns and the way circulation lines were ordered.

The classification shows two different resources for rainfall in this basin.

A: Those rain systems that are entered to the country from the West and South affect this basin. These systems humidity are caused by the Red Sea, the Mediterranean sea, the Black Sea, and the Atlantic Ocean. (B) Some parts of the Caspian coast rainfalls and the northern part of the Alborz mountain that has received their humidity from the Caspian Sea and it has infiltrated northern high-land, causes the rainfalls. It enters the basin from the wide valley of Sefid Rood. According to the rainfall measuring stations data, the least rainfall area is in western, which includes low-land areas. And the most rainfall area is its northern east. Rainfall in this area, in terms of rainfall time distribution in a year, is the Mediterranean. It does not involve a complete dry climate in summer and it takes 3 to 4 percent of the total rainfall.  Rainfall in the basin, respectively, is distributed in winter, spring, fall, and summer.

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Deforestation or vegetation degradation is one of the main drivers of global earth changes, which has significant consequences in terms of ecosystem performance and biodiversity conservation. One of the ways for studying vegetation changes as the most important indicator of land degradation is remote sensing. In this study, in order to monitor the vegetation degradation trend in Ilam Province.After obtaining and preparing the required data (410 downloaded images) in the ArcGIS and Surfer software, the multiplication, mosaic and georeferencing operations are made. Converting format of images into ASCII is the next stage of the study. By converting this format, the total number of 953552 pixels is studied within the range; after removing the lost and negative values, 328042 pixels are analyzed. Besides, using parametric statistical method of the classical linear regression and programming in R software, the trend of slope variations and significance of slope variations of vegetations are obtained for the 17-year period (2000-2016). Results of this study show that the focus of the highest trend of declining slope variations (trend of negative slop variations) is in the NDVI index across the western half of the studied area and the focus of the highest trend of increasing slope variations (trend of positive slop variations) is in the NDVI index in the center and east. Significance of the trend of slope variations also approves this claim. Thus, the focus of the highest trend of slope variations (negative) in the west and southwest of the studied area along with the highest trend of slope variations (positive) in the center and east is significant at the probable level of 0.05
 

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The effect of Urban Development on Watershed Hydrological Properties (case study: Tajrish Watershed)
Throughout the human history, societies and rivers have been closely linked, so that the human civilization began from the riverside (Stevaux et al. 2009 (. The quantitative and qualitative characteristic of river is vulnerable to land-use changes (Kang et al. 2010). Natural and urban watersheds are influenced by the rapid land use change due to urban development (Furusho et al. 2013). Hence the importance of land use as an environmental variable have made its changes as a major issue in environmental changes and sustainable development) Verburg et al. 2009).
The development of urbanization and industrialization of cities and communities have undesirable effects on the hydrological response of watersheds. It increases the magnitude of runoff and contamination, reduces the base flow and the groundwater recharge. Hence, urban authorities are urged to pay more attention to the environmental damaging effects of the urbanization process and the increase of construction. In this regard, attention should be paid to the effect of type of land cover and land use on urban runoff and hydrological changes in surface flow. Tehran as the largest metropolis in Iran has ascending trend of land cover and land use changes due to the growing population.
In this research, the effect of urban development on the hydrological characteristics of the Tajrish sub-watershed (in Darband watershed) located north of Tehran has been investigated. Results of this study indicated that the river Darband is exposed to hydrological hazard due to human need for space and land use and land cover changes. The studied area is affected by decreasing pervious area, increase of runoff coefficient, and change in water quality parameters.
Darband River watershed consists of two streams of Darband and Golabdareh which are considered as the major rivers of the Tehran-Karaj Basin. This river originates from the mountains of the Tochal located in northern Tehran. The catchment area of Darband River in the studied area is 39.88 square kilometers.
In this study, aerial photos of years 1345, 1358 and also   and IkONOS images in year 2011 were used to detect the changes in land cover and land use in the Tajrish watershed. Pas-Ghale sub-watershed in upstream of Tajrish was selected as benchmark since its land use doesn't affected by human interventions. SCS-CN method developed by the United States Department of Agriculture (USDA) was used to estimate the quantitative changes in surface storage and runoff volume. Man-Kendall test was used for temporal trend detection of discharge and chemical parameters of surface water and also. The change of water type was identified annually using the Piper diagram in the aqQA software. Frequency analysis was carried out for peak discharge data using the weibull’s empirical method.
During three considered periods, the curve numbers (CN) and runoff coefficient (C) in Tajrish watershed significantly increased. Significant trend was also observed for the chemical parameters of surface flow in Tajrish. While the surface storage and initial abstraction ratio (λ) indicate decreasing trend.  Relationships of CN and λ with rainfall depth (P) were also computed for both studied watersheds. According to the Piper diagram, the distribution of ions in the cation diagrams at both Maghsudbeik and Pasghaleh stations is generally more directed toward sodium. In the triangles of anions, both of the stations studied tend to show more calcium biocarbon content. Presence of sodium ion in the surface water is due to igneous formations in the watershed. The surface water in Pasghale station, indicate a neutral type of water. Whereas, saline water type is detected in the Maghsudbeik station. The increase of urban utilization over the past three decades could be the main cause of changes in the hydro chemical characteristics and water type along the Darband River.
Investigation of land use changes in the Darband watershed indicate that the impervious surface has increased during years of 1996 to 2011. Results also indicate that the CN and λ values in Pas-ghale watershed are more correlated to Pin compared with ones observed in Tajrish. The results also reveal that hydrological modeling in watersheds undergoes land use changes and urbanization will result in imprecision results.
 Many chemical parameters of the water quality of Darband River have been increasing at the Maghsudbeik station such as Chlorine, sulfate, sodium, electric conductivity and TDS and in the coming years, it can be considered inappropriate in terms of agriculture in the water class.
 
Keywords: Darband River, land cover and land use, Piper diagram, SCS-CN.
 
 

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Resilience, as a concept to confront abnormalities, surprises and unexpected changes in recent years has been raised as the ability of places, societies, and systems to respond to the dangers of tensions and pressures; so that the system can quickly return to pre-stressed situation, threats It accepts the future and confronts them. Central region of Iran according to the zoning studies of the national physical plan of Iran, including three provinces of Isfahan, Chaharmahal and Bakhtiari and Yazd, in a desert climate with many crises in the permafrost environment that has disturbed the state of resilience of the region, and as a result the scheme and target application regional resilience on policy and planning to reduce vulnerability and to cope with various trans-regional crises. Despite the fact that the concept of resilience at the level beyond the city has become apparent, there is still no clear framework for measuring this situation at the regional level. Based on this research, it is believed by the trans-regional and multi-dimensional nature of the resilience that by modifying and applying the concept of resilience to the integrated and multi-dimensional at the regional level, an appropriate framework for status measurement regional resilience in the form of a composite index and thereby risk reduction planning and promoting the resilience of the presentation To give. In this regard, the major purpose of the research is to develop an optimal framework for assessing, measuring and ranking the resilience situation in the central region of Iran. The results show that Chaharmahal and Bakhtiari province have the highest resilience and then there are two provinces of Isfahan and Yazd, respectively. In the meantime, Yazd province has the lowest resilience among the provinces of the central region; therefore, it is necessary to focus on planning and allocating resources to promote and improve priority sectors. Responding to resilience agendas requires the adoption of transregional planning and decision-making approaches such as environmental regionalism.

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Analysis and zoning of thermal physiological stresses in Iran
 
Abstract
Human health is influenced by weather variables in all circumstances, including atmospheric pressure, humidity and temperature around them. Based on climate hazard and climate changes, different parts of human life and economic and social strategies such as health, hydrological pollutants And agriculture had a profound effect, including the discussion of the effects of thermal stress on human health over the last few decades, and has become a major issue in the world's scientific circles. Heat and cold stresses, the exposure of humans to extreme heat and cold, are part of the extreme events, often encountered by people during daily activities or in the workplace, and affecting human physical activities. It is important that, if the body is not cooled through transpiration or cooling mechanism, severe deaths are inflicted on human health; therefore, the person has to reduce his activity in order to reduce the adverse effects of heat stress. Hence, many researchers consider the thermal stress component more important than other components in assessing human health.
In this study, using the physiological equivalent thermometer of PET thermal stress assessment and zoning of human thermal physiological stresses in Iran, with the length of the common statistical period from 1959 to 2011, and for the arsenal of thermal physiological stresses of Iran Forty stations have been used as representatives of Iranian cities. To calculate the physiological equivalent thermal temperature, all the effective meteorological elements in the human energy bill are measured at an appropriate height of climate biology, such as 1/5 meters above the Earth's surface. Data on climatic elements are provided by the Meteorological Organization of Iran. In the absence of data for some courses, linear regression method was used to reconstruct these missing data. After calculating the indices, the frequencies were also monitored and finally, using the GIS technique, the Kriging method of the study area was based on the frequency of occurrence of the indicators. Therefore, in order to achieve the results and objectives of the present study, software such as SPSS for data normalization as well as missing data was analyzed and analyzed using Ray Man's model based on meteorological elements to calculate the equivalent thermal physiological temperature of humans. Also, using the GIS software and Ordinary Kriging method, the best interpolation method was used to zon the human cysiological stresses.
Today, in the planning of human health and comfort, the study of the physiological thermal stress plays an important role. In this regard, weather conditions can be used in the long-term planning of climate and in the short term planning of atmospheric conditions. In the present study, using the thermophysical Thermal Equivalent Thermal Index (PET), the climate climatic Atlas of Iran was prepared on a monthly basis. Calculated values for 40 stations in the country with a total statistical period of 52 years (1959-2011) were prepared. The results of this study showed that the spatial distribution of the physiological equivalent thermal temperature index in the country follows the altitudes, roughness and latitude. Accordingly, the low values of the indicator, which relate to the stresses of the cold, are consistent with the high and mountainous regions as well as the high latitudes, and vice versa, the thermal stresses occur in low and low elevations, as well as low latitudes, which of course, severe heat stresses occurred in the summer. Because throughout this season, the entire country of Iran is dominated by high tidal altitudes at high and low levels of ground pressure (1000 hp) with its warm and dry air, causing extreme heat and The term effects of heat waves on humans, heat loss, thermal contraction of the muscles and skin dryness, infectious or skin diseases, inflammation, sunburn, dizziness, fatigue, and mortality due to an increase in allergies can be mentioned. Significant differences in the environmental conditions of the mountainous masses of Kerman, Yazd and Sistan and Baluchestan provinces with their surrounding areas or low and low northern areas, and especially the Moghan Plain and Sarakhs plain, located in the upper latitudes of the country The issue is that the role of elevation in spatial distribution of the country's climate is much more colorful than factors such as latitude and longitude. The results of the analysis of the monthly thermal physiological stress maps showed that in terms of the area without tension, the march of the month with 47/8% of the area (778424/2km²) is in the first place and has the most favorable environmental conditions, The moon with 43/5 percent of the area (709275/2km²) is in the second position and also in March with 22.6 (359128/9km²) in the third, August and the last month. The highest thermal stresses (29

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Evaluation the best of selective base period of GCM models to determine meteorological variables of Birjand station in future periods
 
Abstract:
Nowadays, determining the effect of a climate change in the various aspects of human life is quite evident. In such a situation, it is very important to determine the base period, which determines the effects of a climate change than in this period. Choosing a course-based course plays an important role in choosing future courses to conduct research on the effects of climate change. Many researchers in the research use the LARS-WG dynamic downscale method or the statistical method to measure the weather variables, which should be the same for the years of the base period and the upcoming period.
This research was conducted to select the appropriate base course for estimating minimum temperature, maximum temperature and precipitation at the synoptic station in Birjand. The station is located at latitude 32 degrees and 53 degrees east and 59 degrees and 17 degrees north latitude. In order to evaluate and accuracy of the methods in this research, seven criteria for estimating root mean square error (RMSE) and mean absolute error (MAE), relative error (RD), mean relative error of the month of the year (MRDM), average relative error of the month in the year (RDMM), PBIAS and RSR. In this study, using GCM models, we assessed the selected base courses for the synoptic station in Birjand. To doing in the research, an amount of 27 base courses from 35 models of the fifth report of the change were compared with similar periods obtained from the station in Birjand.
The results showed about precipitation that the duration of the base periods such as 1960-2005 and 1960-2000 is less of the RMSE and MAE errors than the rest of the courses, and the base period of 1965-1990 between periods less than 30 years and the period The 1990-1960s are also well suited to the precipitation data of the synoptic station. The maximum temperature of the 1960-1990, 1960-1985 and 1960-1995 is the lowest RMSE error. However, short-term courses of 1980-1960 and 1965-1985 present satisfactory results.In the case of minimum temperatures, periods of 21 and 31 years 1960-1980, 1960-1985, 1960-1990 and 1965- 1985 have a percentage error of RMSE and a lower percentage of PBIAS. Variable variation range can also be used to show the appropriate base course. The result showed that the periods 1960-2005 and 1970-2005 had a lower range of rainfall variation than the other variables and seems to be more suitable. However, courses such as 1990-2000, 1975-1995, and 1995-2005 have less certainty. The more courses that go into periods with shorter periods of time, the more modest and less certainty they will be. Also, if you look at changes in the 1975-2005 periods and the 1965-1995 periods, it will be clear how much each year towards the years closest to 2005 will be deducted from the precipitation daily average.
The results also show that maximum temperature changes are better than precipitation, and all courses have less variation range. Nevertheless, the period of 1960-2005 has the highest degree of certainty and the period of 1975-2005 has the least degree of certainty compared to the rest of the courses. In contrast to precipitation, there are periods such as 1970-1990, which, if considered as the basis for research, provide more certainty than the longer period of 1965-2005 for maximum temperature. Also, what's most clear about the maximum temperature is the higher the period with years closer to 2005, the temperature increases, which will increase the temperature over time.
The process of minimum temperature variations also indicates that in addition these changes are similar to the change in temperature, with the difference that the range of variations in the minimum temperature is somewhat higher than the maximum temperature. The period of 1960-2005 has the best degree of certainty and the period from 1975-2005 has the least degree of certainty than the rest of the courses. Although long periods of time are less certain than short periods, the result is that the longer the interval between periods increases, the more precise the results will be. The result is not entirely correct, 1975-2000 is less certainty than the 1965-2000 period and has better results in minimum temperatures. Therefore, the evaluation of selected periods of GCM models with similar periods from observations of Birjand station shows that for rainfall variables, periods with a number of years yield more satisfactory results, but for two variables the minimum temperature and maximum temperature of the periods, not long or short periods, provide less risk of RMSE and PBIAS than long periods.
Keywords: climate change, GCM model, base period, meteorological variable, emotion scenario
 
 
 

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Study changes and spatial pattern seasonal of outgoing long wave radiation in IRAN
 
Introduction
Changes in OLR can be considered as a critical indicator of climate change and hazard; studies have shown that since 1985, long-range radiation has increased the output of the Earth and is a cause of increased heat in the troposphere. This has led to an increase in drought and a slight decrease in the cloud in the upper terposphere, as well as an increase in Hadley's rotation toward higher latitudes. On the other hand, clouds play an important role in the long-wave changes of the Earth's output and are adequately evaluated at the global energy scale at all spatial and temporal scales.
Data and methods
In the present study, in order to calculate the variability and the pattern of seasonal spatial dependence of the long-range radiation output of Iran, OLR data from 1974 to 1976 were daily updated from the NCEP / NCAR databases of the National Oceanic and Oceanographic Organization of the United States of America. To calculate Iran's long-range output radiation, in the Iranian atmosphere (from 25 to 40 degrees north and 42.5 to 65 degrees east), using Grads and GIS software. First, the general characteristics of the earth's long wave were investigated. To obtain an overview of the spatial status of the seasonal changes of the long-wave and its variability over the country, the average maps and coefficients of the long-wave variations of the earth's output were plotted in the spring, summer, fall, and winter seasons. In this study, the slope of linear regression methods using mini tab software was used for trend analysis. Hotspot analysis uses Getis-Ord Gi statistics for all the data.
Explaining the results
The results of this study showed that the mean of long wave in Iran is 262.3 W/m². The highest mean long-range radiation output in spring, autumn, and winter is related to latitudes below 30 degrees north, especially in the south and south-east of Iran, with the highest mean in autumn and winter with wavelengths. High output 282-274 W/m² as well as spring with mean W/m² 295-291 below latitude 27.5° C, which is in Sistan and Baluchestan provinces, south and southeast of  Fars. Hormozgan has also been observed; the lowest OLR average in these seasons is observed above latitude 30 ° N in the northwestern provinces with the lowest mean in the season Yew and winter with mean long wavelength output 213-225 W/m² and also observed in spring with mean 226-235 W/m² at latitude 37.5 ° C and latitude 44 ° N in Maku and Chaldaran Is. In summer, the highest OLR averages of 316-307 W/m² are observed in east of Iran with centralization of Zabol, Kavir plain and Tabas desert as well as west of Iran in Kermanshah, Khuzestan and Ilam provinces, with central length The latitude is 47.50 degrees north and latitude 32/32 east in Ilam province in the city of Musian, due to desertification, saltwater and sand, as well as the absence of high clouds, indicating an increase in the frequency of earthquakes and It is a drought that will lead to shortage of rainfall and increased rainfall in these areas; the lowest average long-range radiation output in summer with W/m² 235-226 extends as a narrow strip from southeast to Chabahar and extends to the middle Zagros highlands in Chaharmahal Bakhtiari province and northwest areas in Maku, Chaldaran, Khoi, Jolfa, Marand, Varzegan, Kalibar, Parsabad, Ahar and Grammy cities. It has also been observed in the northern coastal provinces of Iran including Mazandaran, Gilan, Astara, Talesh, Namin. According to the trend of long-wave radiation output of Iran increased by 0.16 W/m² and decreased by 0.37 W / m2 with increasing latitude. Seasonal trends indicate that 100 percent of the country has a significant increase in winter and no significant fall in autumn. 21.24% in summer and 18.35% in spring have no significant decreasing trend, which in south-east includes Sistan and Baluchestan, Kerman, Fars and Hormozgan provinces and 78.76% in summer and 81.65% in summer. Spring has a significant non-significant upward trend. The spatial dependence of the hot spots on Iran's long-wave radiation at 90, 95 and 99% confidence levels is 45.49% in spring, 37.57 in autumn, and 44.55% in winter. The high wave radiation of summer is 42.2%, which is observed in north of Sistan and Baluchestan province with central Zabul and in east of Lot and Tabas desert and in west of Ilam province with central of Musian. But in spring, autumn and winter in the south and southeast of the country including Sistan and Baluchestan, Hormozgan, Kerman, South Fars, Bushehr provinces and in central Iran including Lot Plains, Desert and Salt Lake and Tabas sandy desert. It is also observed in western Iran in Ilam province, so that these areas correspond to the tropical belt at latitude 30 degrees north. This is due to its location in the subtropical region, the low latitude of Iran, especially south and southeast to central Iran including Lut Plain, Desert and Tabas Desert due to its proximity to the equator, the angle of sunlight is higher and perpendicular. Spun. The spatial dependence of cold spots on long-wave radiation at 90, 95 and 99% confidence levels in spring is 33.44%, autumn is 41.41% and in winter is 44.55%. Cold spots of long-wave radiation are 25.5% in the summer, located at latitudes above 35 ° N in the subtropical belt and include northeast areas in North Khorasan Province in the cities of Bojnourd, Esfarain, Jajarm, Mane and Semlaghan, Safi Abad and northern coastal areas in Golestan, Mazandaran, Guilan, and northwestern provinces of Iran including Ardabil, East and West Azerbaijan, Qazvin and Zanjan North Tfaat Kvh¬Hay Zagros includes the provinces of Kurdistan, Hamedan, Markazi, Qom, Kermanshah North East part. Minimum OLR cold spot with average output longwave radiation of 213 W/m² 220 northwest of Khoy, Maku, Chaldaran, Jolfa and Marand can be an indicative role for determining convective activity and dynamic / frontal precipitation.
Keywords: Temporal and Spatial Variations-OLR-Spatial Index of Statistics Gi.
 

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 Introduction
Old trees are important and key elements of forest sites and are of great value in terms of forest management, reforestation, silviculture and ecology. Although old trees constitute a small percentage of forest trees, they account for a large share of forest carbon reserve and play a vital role in carbon storage. Understanding the how geographical and site distribution of these trees across the forest is essential to obtain information for forest restoration management. Therefore, this study was carried out to investigate the geographical and site characteristics of old trees of Wing nut, Ash, Hackberry, Sycamore, Elm, Olive, Cypress and Fig in Ilam province.
 
Materials and methods
After querying the villagers and local people and conducting numerous forest surveys, the old trees were identified and selected on the basis of the diameter of the breast. Then their geographical characteristics including city, district, village, geographical coordinates and site conditions including slope, aspect, altitude, soil depth, climate and proximity to water source were measured or recorded.

Results and discussion
The results showed that in terms of geographically distribution, the identified old trees have located in Ilam, Mehran, Malekshahi, Badreh and Dehloran cities. Topographically, the old trees of Wing nut, Elm, Ash and Fig were located in the 0-10% slope class, Hackberry and sycamore in the 0-10% and 10-30% slope classes, olive in the 10-30% slope class and Cypress in the 40-70% slope class. The old trees of Wing nut, elm, Ash and Hackberry were located in the north aspect, fig, sycamore and Cypress in the south aspect and olive in the west and south aspects. The old trees of Wing nut, elm, Ash, Hackberry, Sycamore and Cypress were dispersed at altitude class of 1100–1250 m and olive and fig old trees were at altitude class of 1250–1400 m above sea level. Climatically, the old trees of Wing nut, elm, Ash and Hackberry were located in the very cold Mediterranean climate, Cypress trees and some sycamore trees in the cold Mediterranean climate, and fig, olive and some plantain trees were in the semiarid cold climate. In terms of access to water resources, old trees of Wing nut, elm, Ash, Sycamore, Hackberry and Fig were located on the bed or margin of river, old Cypress trees had no access to water resources and some olive trees were close to water resources. In terms of soil subsidence, old trees of Wing nut, elm, Hackberry, olive, and fig were mostly in soils with medium depths. Old ash and sycamore trees were present in shallow to medium depths and old cypress trees were present in shallower soils. Although the identified old trees were present in limited sites, their long-term and sustained presence in these sites indicates that sites conditions are favorable for their survival.

Conclusion
Therefore, it can be concluded that the presence of low slopes, suitable soil bed and access to water resources were desirable characteristics for stability and survival of the studied old trees in these sites. Due to the above-mentioned characteristics, ecologically similar sites can be found in the forests of the province and can be restored by seed of old and resistant trees.
Keywords: Site, Topography, Climate, Geography, Old trees, Ilam

 

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Predicting the average annual maximum wind speed in Sistan region using spatio-temporal regression method
: Abstract                              
The wind is a quantitative vector that moves from high-pressure centers to low-pressure centers and is measured by two factors, the direction of the wind, which originates from the north and increases in degrees clockwise, and the wind speed, which is the horizontal flow. Air is measured in units of time. The wind speed can move colloidal particles, including clay and silt, from the site of destruction to a distance of hundreds of kilometers. Studies show that most dust days occur in the eastern regions of the country so that in the range of 120-day winds in Sistan, the frequency of dust per year reaches more than 150 days. Moreover, the prediction of numerical values ​​of maximum annual wind speed using the Spatio-temporal regression method was considered in this study. Error variance and alignment analysis using variance inflation index showed that numerical models of the Spatio-temporal regression of data could predict the Average maximum wind speed in the coming years. The results also show that regression Spatio-temporal until 2022 can predict wind speed.
The numerical model indicates that the lowest annual average wind speed from 2019 to 2022 is related to the Ghaen station. Its forecast trend shows that by 2022, the average annual wind speed will decrease. The highest annual average wind speed is related to Zabol station, in which the forecast trend of this station shows that the average annual wind speed will decrease by 2022.

Keywords: Spatio-temporal regression, Wind speed prediction, Sistan region
 

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The expansion of the pole toward the tropical belt is thought to be due to climate change caused by human activities, in particular the increase in greenhouse gases and land use change. The variability of the tropical belt width to higher latitudes indicates the expansion of the subtropical arid region, which indicates an increase in the frequency of drought in each hemisphere. In order to change the width of the tropical belt of the Northern Hemisphere in the middle offerings, indices of  precipitation minus evaporation, wind vector orbital component, stream function, tropopause surface temperature, OLR, and SLP have been used. Findings showed that the expansion of tropical belt latitude with stream function to higher latitudes with 1° to 3° latitude and the effect of Hadley circulation subsidence has increased the amplitude of evaporation minus precipitation has shown that the fraction of precipitation minus evaporation 1° to 3° latitude geographically increased. The subtropical jet has increased the movement of the upper branches of troposphere from the Hadley circulation by 2° to 4° latitude, which can have a negative effect on transient humidification systems as well as on the amount of precipitation. The extension of the pole towards the tropical belt, which is a consequence of climate change and hazards, will lead to the displacement of the pole towards the tropical side of the river, thus providing dry tropical belts to the pole; Also, the long-wave radiation of the earth's output has increased by 1° to 2° latitude and has caused an increase in heat in the upper troposphere, which has increased the dryness and slightly reduced the clouds in the upper troposphere and also caused the tropical belt to expand to higher latitudes. Has been. In general, the research findings showed that most tropical belt indicators have been increasing since 1979.

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Cold and frost are one of the climatic hazards that cause damage to various activities every year. Climate change, on the other hand, causes spatial and temporal changes in glaciation. The purpose of this study is to analyze the temporal-spatial changes and predict the future of glaciers in Hamadan province. CanESM2 model was used to predict the minimum daily temperature in the province. Data mining of general circulation models was Downscaling using LARS-WG model. The above parameters were simulated for a period of 30 years (2050-2021) under three scenarios RCP2.6, RCP4.5 and RCP8.5 for selected stations. The results of the monthly minimum temperature survey in the study stations of the province showed that the minimum temperature in the period (2050-2021) in all studied stations according to all three scenarios will increase in all months of the year compared to the base period. The average minimum temperature of the province is equal to 2.5 degrees Celsius, which in the coming decades based on the scenarios of RCP2.6, RCP4.5 and RCP8.5 will reach 6, 6.2 and 6.3 degrees Celsius, respectively, which is the highest The changes are related to Nojeh station and the lowest is related to Hamedan. The spatial distribution of the beginning and end of freezing in the future period indicates that freezing in the northeastern and northern parts of the province starts earlier and ends later than in other parts of the province, while in the southern parts of the province it starts later and ends earlier. The results of examining the changes in the onset of frost in the next decade compared to the base period showed that in all stations studied the onset of frost will decrease between 3 to 11 days.