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.
Valiollah Karimi; Eassa Kia; Mohammad Ali Maleki
Abstract
Extended AbstractIntroductionIndustrialization of communities and increased greenhouse gasses in the previous decades have resulted in increased global temperature and changes in climate parameters which are generally called climate change in scientific texts. Climate change has resulted in changes of ...
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Extended AbstractIntroductionIndustrialization of communities and increased greenhouse gasses in the previous decades have resulted in increased global temperature and changes in climate parameters which are generally called climate change in scientific texts. Climate change has resulted in changes of temporal and local precipitation patterns all around the world. Consequently, hydrological cycle has changed affecting intensity, duration and frequency of rainfall events. Intensity- duration- frequency curves are used to provide an economic and safe design for drainage facilities, check dams, urban water management structures such as culverts, surface water and sewage systems. They are also used in landslides studies. The present study seeks to compare rainfall intensities in Babolsar Synoptic Station before and after 1993 to understand the effect of climate changes on rainfall intensities during the mentioned 52-year statistical period. Materials&MethodsThe first synoptic station of Mazandaran province was set up in Babolsar city in 1952. With an elevation of -21 m from sea level and 7 m from the Caspian Sea level, it is located at the east longitude of 52o, 39̍, 30̎ and the north latitude of 36o, 43. The station has a mean annual rainfall of 928 mm and an average of 99 rainy days.To understand the effect of climate changes on rainfall intensities in different durations and return periods in Babolsar Synoptic Station, statistical period was divided into two 26-year subperiods (before: from 1968 to 1993 and after: from 1994 to 2019). Rainfall intensities were calculated separately for each of the 14 duration series (10, 20, 30, 40, 50, 60, 90 minutes and 2, 4, 6, 9, 12, 18 and 24 hours) with return periods of 2, 5, 10, 25, 50 and 100 years and compared together. Then, a paired t-test was conducted to prove the difference between two series of rainfall intensity to be significant. Moreover, 5 annual air temperature parameters including minimum absolute temperature, maximum absolute temperature, average minimum temperature, average maximum temperature and average temperature were investigated in both subperiods and analyzed using a paired t-test in SPSS software. Results were used to investigate temperature and precipitation changes during the statistical period and prove the difference between before and after time series data to be significant. Mann-Kendall test was also carried out on 5 air temperature parameters collected during the 52-year time series data to find ascending or descending trends. Results&DiscussionCompared to the first subperiod, the average rainfall intensities have increased in 10, 20, 30 minute and 12, 18 and 24-hour durations of the second statistical subperiod, while the opposite has occurred in 40, 50, 60, 90-minute, and 2, 4, 6 and 9-hour durations. However, statistical analysis has proved increased rainfall intensities in 10 and 20-minute, and 18 and 24-hour durations and decreased rainfall intensities in 50, 60, 90-minute, and 2, 4, 6 and 9-hour durations of the second statistical period to be significant. A paired t-test was conducted to compare rainfall intensity in the statistical subperiods and find out its effects on climate change. Results indicated that except for data collected in 30 and 40-minute and 12-hour durations, the difference between other paired series was significant at a less than 5% level.Moreover, except for maximum absolute air temperature, other air temperature parameters showed a significant difference at less than 0.5% level. Furthermore, all 5 parameters showed an increase in the second study period indicating a warmer climate in Babolsar.However, paired t-test results indicated that despite the reduction of mean annual rainfall in the second statistical period, difference between the two series was not significant at any acceptable level of significance. Moreover, results of the Mann-Kendall test indicated that average air temperature, average maximum air temperature, average minimum air temperature and minimum absolute air temperature have shown an ascending trend at a 1% significant level, while maximum absolute temperature lacked a specific trend and showed leap changes. Annual rainfall also showed random changes and lacked a specific trend during the 52 year statistical period. ConclusionResults of the Man-Kendall and paired t-test have shown that a significant increase have occurred in air temperature during the 52-year statistical period (1968-2019) resulting in climate changes.It can be concluded that climate change has increased the intensity of short-term (shorter than 40 minutes) and long-term (longer than 12 hours) precipitations and reduced the intensity of medium-term precipitations in Babolsar Synoptic Station. Moreover, climate change has increased the intensity of precipitations with short and long return periods while reducing the intensity of precipitations with medium-term return periods in the aforementioned Synoptic Station.