Spatial planning with regard to military defense
Mohammad Hassan Nami
Abstract
Extended Abstract Introduction Gradual changes in climate systems and patterns such as temperature, humidity, cloudiness, and wind and precipitation patterns affect type of climate in different areas. The climate of lagoons is especially sensitive and easily affected by climate changes. Critical ecosystems ...
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Extended Abstract Introduction Gradual changes in climate systems and patterns such as temperature, humidity, cloudiness, and wind and precipitation patterns affect type of climate in different areas. The climate of lagoons is especially sensitive and easily affected by climate changes. Critical ecosystems of lagoons protect biodiversity and have various tourism, economical, ecological, environmental and social values. Located in JazMurian basin, JazMurian wetland is frequently affected by wet years and droughts. However, repeated droughts and loss of freshwater have resulted in the wetland drying out. The dried out water body not only affects plant and animal life, but also acts as a dust emission center.Material and MethodsThree scenarios of emission (A2, A1B, B1) in medium-term (2046-2065) and long-term (2080-2100) are used in the present study to evaluate climate changes in JazMurian basin. Related data have been collected from Iranshahr synoptic station in the east and JiroftMianDeh in the west during 1990-2010 statistical period. The output of HADCM3 model has been downscaled using LARS-WG statistical model and minimum/maximum temperature, and monthly precipitation of the synoptic stations were analyzed.DiscussionEvaluation of LARS-WG model proved that monthly and annual average of minimum and maximum temperature in all modeling scenarios are higher than the observation period. The highest and lowest temperature increase will occur in A2 (business as usual) and B1 (the most environmental) scenarios. The highest increase in monthly average of maximum temperature will occur in Iranshahr station during the long-term A2 scenario (4.3 for maximum temperature in April and 4.6 for minimum temperature in May). In Iranshahr station, the highest increase in monthly average of maximum temperature predicted for the medium-term A2 scenario will equal 2.5 ° in April. In both scenarios, the lowest increase in monthly average of maximum temperature in Iranshahr will occur in October.According to all scenarios, precipitation will decrease in January and December. An increase in precipitation is recorded during March and October in Iranshahr station, and during February in Jiroft. Thus, changes will mainly occur in Mediterranean winter precipitation in the study area, while negligible changes will occur in monsoon precipitation during summer. Precipitation modeling shows higher precipitation fluctuation in long-term scenario compared to the basic statistical period. Long-term A 1B and B1 scenarios have predicted a small increase in precipitation of both stations compared to the basic statistical period. A2 scenario has shown a small decrease in precipitation during the same period. Modelling based on B1 scenario has indicated that the region will experience a higher increase in precipitation in long-term future (2080-2100) compared to the medium-term future (2046-2065), while the other two scenarios have predicted a lower increase in precipitation of the same period. Medium-term B1 scenario has predicted a lower annual precipitation average compared to the observation period. Results indicated that in accordance with the B1 scenario, Iran will experience the lowest level of precipitation during the 21 century in the medium-term period.ConclusionInvestigating various meteorological parameters in western and eastern borders of JazMorian basin has predicted 1.5° to 2.1° increase in average temperature during the future 50 years, and 2.4° to 3.9° increase in average temperature during the future 100 years. Moreover, results indicated that changes will mostly occur in winter precipitation, and summer time changes will be negligible. All things considered, all scenarios have predicted lower precipitation for eastern parts of JazMurian compared to the western parts.
AhmadReza Ghasemi; Foruh Sadat Sayedi
Abstract
Wind is one of the main elements in the climate of each region,and its changes can affect phenomena such as dust storms and the severity of evapotranspiration.The declining trends of surface windreported by previous studies are generally small, but it is still important to assess the distribution of ...
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Wind is one of the main elements in the climate of each region,and its changes can affect phenomena such as dust storms and the severity of evapotranspiration.The declining trends of surface windreported by previous studies are generally small, but it is still important to assess the distribution of the trend of wind speed at the continental to global scale in order to betterunderstand the causes of the trend. This research was carried out aiming to predict wind speed in Iran by 2020 with the Holt-Winters model and using data from a 50-year statistical period (1961-2010). The results showed that this model has the ability to predict wind speed in most parts of the country. The values of the coefficient of explanation of this model varied in 34 stations under survey from 0.39 in Abadan to 80.0 in Babolsar, and the error values in most of these stations were acceptable. The results of Kolmogorov-Smirnov test used to evaluate the normalized residuals of model showed that the model residuals are normal in most of the stations that show the suitability of the model to estimate and predict the wind speed in Iran.The results showed that this model has also simulated the wind speed extreme values in most stations as well. The results of the Holt-Winters model to predict wind speed by 2020, indicate that wind speed in the Eastern half of the country as well as the southern slopes of the Alborz, which have dry and semi-arid climates, will increase by 2020, while the Western half, Southwestern and central regions of the country will experience a decreasing trend of wind speed. The maximum amount of wind speed increase will be at Gorgan station by 2020 with a value of 1.8 meters per second, and themaximum rate of wind speed reduction will occur in southwest stations of the country, so that in the Abadan station, wind speed will decrease from 48.6 m / s to 31.8 m / s by 2020.In other words, we can say that the wind speed in most arid and semiarid regions of the country will increasein the future, while moderate and mountainous areas in western parts of the country will experience a decreasing wind speed.
Ahmad Pour Ahmad; Mohammad Komeili
Volume 20, Issue 78 , August 2011, , Pages 50-57
Abstract
Until now, a major application of scientific methods has been to estimate and predict the values of a variable by referring to the values of one or more other variables associated with it. In this paper, we examine the most common type of "correlation", or estimation based on structural relationships ...
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Until now, a major application of scientific methods has been to estimate and predict the values of a variable by referring to the values of one or more other variables associated with it. In this paper, we examine the most common type of "correlation", or estimation based on structural relationships between variables, which leads to the creation of a simple linear model. The use of linear models in a variety of urban analyses is quite commonly accepted due to the relative simplicity and accuracy of these models. Linear models usually show tendencies over time, which may not be taken into account through abstract or chart-based analyses. Linear models are used to express events when non-scientific methods are incomplete and unsatisfactory (and predict the appearance and time of the events).
