جستجوی مقالات مرتبط با کلیدواژه « تغییرات اقلیمی » در نشریات گروه « محیط زیست »

Dust is a common phenomenon in arid and semi-arid regions. One of the factorsthat play a role in the occurrence of this phenomenon is the change in weather conditions, whichleads to drought, and the drying of lakes and rivers has caused crises such as sandstorms. Thisphenomenon leads to negative effects on agriculture, water and soil pollution, and respiratorydiseases, as well as environmental and social challenges such as reduced visibility and roadaccidents. The purpose of this research is to investigate the relationship between the DSI dustindex and SPI standardized precipitation drought index in Semnan Province.

The studied area of Semnan Province is located in the southern regionof the Alborz Mountain range. To investigate the effect of drought on the amount of dust, thedaily data of dust, monthly rainfall, temperature, relative humidity and evapotranspiration offive synoptic stations of Semnan Province within a period of 15 years (2003-2017) were usedon an annual scale. During a 15-year period, the drought storm index (DSI) was determined forthe synoptic stations using the dust storm index, and then the cumulative DSI index wascalculated. Afterwards, statistical and experimental evaluations was done on annualfluctuations to identify potential trends. Also, experiment and linear regression analysis wereused to evaluate the correlation of standard precipitation index and dust storms, and Arc GISsoftware was used for zoning.

The results showed that the average annual temperature in the regionhas increased from 2003 to 2017. This rapid warming has caused drought and as a result,temperature, evaporation and transpiration have also increased and led to a decrease in rainfall.A month-by-month survey of wind speed in different stations showed that there is a possibilityof dust in the province in the months of June and July when the maximum wind speed prevails.On the contrary, the months of December and January experienced the least occurrence of dust.The annual changes of DSI (2003 to 2017) showed an irregular shape and do not have a trend.Thus, in 2011, the intensity of dust was high and decreased in the following year, and the samewas observed in 2016. According to the SPI index, Semnan Province was in the normal droughtcategory with a score of 0.59. The in-depth analysis of the correlation chart between thestandardized rainfall indices and DSI showed that the DSI has increased along with the severityof drought during the study period and there is a good correlation between the DSI index andthe meteorological drought in the region, so that when there was a drought period, the value ofDSI decreased and when it was a drought period, the value of the dust index increased.However, there is no significant relationship between these two indicators (p =0.07 andR2=0.22) during the 15-year research period.

Our findings indicated an increase in dust from the west to the east of the provincedue to the increase in average dust storm days. Correlation results between SPI and DSI indexshowed that although DSI index increased during the analyzed period along with the severityof drought, the correlation between the two was not significant. However, the DSI index trendpattern was consistent with the drought pattern trend. Finally, the correlation between droughtand DSI has always fluctuated according to droughts.

In this research, to anticipate the effects of climate change on the precipitation of selected stations in East Azerbaijan province, including Ahar, Maragheh, Mianeh, Jolfa, Sarab, and Tabriz stations, which had 29-year common statistical data from 1985 to 2014, with The use of LARS-WG6 model were studied. In this research, the effectiveness of the LARW-WG model for generating and simulating daily data of temperature, precipitation, and sunshine hours in the study area was investigated using the statistical parameters R2, MAE, and RMSE. The results showed that at the confidence level of 99%. There is no significant percentage difference between the real data and the data obtained from the model, and the model has the necessary efficiency to generate daily data, therefore, after ensuring the model's ability, using HadGEM2 atmospheric general circulation model under RCP 2.6 scenarios, RCP 4.5 and RCP 8.5 in the next two periods from 2021 to 2040 were forecasted for the rainfall changes in the studied area. The results of forecasting the average annual rainfall changes of the studied stations of East Azerbaijan province in the statistical period of 2021-2040 showed that According to RCP 2.6, precipitation will increase in all the studied stations in the next 20 years, but according to RCP4.5 and RCP8.5, we will see an increase in precipitation only in Jolfa station, and in the rest of the studied stations, precipitation will increase by will be significantly reduced.Climate change is one of the most important and complex concerns of the current and future centuries. The dangerous effects of climate change on human life will cover almost all aspects of life. Drought, rising sea levels, violent storms, reduction of freshwater resources, warming of the air, forest fires, and desertification are among these effects (Mohammadi et al., 1400). Climate change is one of the most important ecological problems of the 21st century. According to the fifth report of the Intergovernmental Panel on Climate Change, these global changes are most likely caused by human factors. Various studies show that this phenomenon can have negative effects on various systems of water resources, agriculture, the environment, industry, and the economy. Forecasting the quantity and quality of climatic changes is one of the complex issues that have occupied the minds of climatologists. Now, with the help of obtaining new technologies and possessing multiple series of necessary data of climatic variables and with the help of knowledge to understand the relationships between these variables, basic steps have emerged in understanding and predicting climatic trends, in such a way that now Computer models all respond to climate forecasting issues and factors affecting climate change within their capabilities (Darvand et al., 1400). Currently, the most reliable and developed tool for investigating climate change and its impacts is the 3D Ocean–Atmosphere General Circulation Model (AOGCM). The AOGCM model is based on physical laws. These relationships are resolved in a three-dimensional network around the world. The presented models show climate parameters in the future (until 2099) for different emission periods. By using these methods with different climatic variables, the effects of climate change on the variability and adaptation of plants can be investigated.The research method in this study relies on the LARS WG model. After sorting, processing data, and preparing input files, finally, the model studied in this research was finally implemented for the basic course. In the next step, using the mean absolute error (MAE), coefficient of determination (R2), and the root mean square error (RMSE) to evaluate the data generated from this model and the real data available in the basic period became After checking the results of the confidence stage and evaluating the capability of the LARS-WG model for simulating meteorological data by considering the low values of the error measurement indices and the high values of the calculated coefficient of determination, the new version of LARS WG6 was used in this research. The required data including minimum temperature, maximum temperature, precipitation, and sunshine hours are collected from the synoptic station of East Azarbaijan province and given as input to the model. The data simulated by the CMIP5 atmospheric general circulation model is related to the period 2021-2040, which under the scenarios of RCP 2.6, RCP 4.5, and RCP 8.5 by the LARS-WG model compared to the base period 2014-1985 in the scale of the studied stations. In order to reduce the uncertainty of the average of the calculated profiles for the above model, it has been obtained. In the current research, it has given appropriate and favorable results regarding the study of the effects of climate change scenarios on the precipitation of East Azarbaijan province in the direction of microscale. CMIP5 models are used in LARS-WG6 software, which is one of the most famous and important models for generating random weather data. This model is used to generate the values of precipitation, maximum temperature, minimum temperature, and sunshine hour in a station, regarding the basic climate conditions as well as the future. For this reason, the study has been done on various stations of the studied area. The daily temperature and precipitation data of 6 stations of East Azarbaijan Province, including Jolfa, Ahar, Sarab, Tabriz, Mianeh, and Maragheh stations, were used for exponential micro-scale as well as temperature and precipitation forecasting during recent years. Then, in the present research, to implement the model, first, taking the 29-year period from 1364 to 1393 (1985-2014) as the base period, the necessary data, including precipitation, minimum and maximum temperature, and sunshine hours, were obtained from the National Meteorological Organization.The results of forecasting changes in the average annual precipitation of the studied stations of East Azerbaijan Province in the statistical period of 2021-2040 showed that according to RCP 2.6, the precipitation will increase in all the studied stations during the next 20 years, but according to RCP 4.5 and In RCP8.5, we will see an increase in rainfall only in Jolfa station, and in the rest of the studied stations, rainfall will decrease significantly.

Investigating the growth and ecological characteristics of trees through dendrochronology will provide essential messages for reconstructing climate models for the past and future. This research investigated the historical, ecological, and climatic characteristics of the Brant's oak (Quercus brantii Lindl.) in Chaharmahal and Bakhtiari provinces. A typical single-stem Q. brantii was selected and cut. Then, a disk sample was prepared. Dry weight and carbon content were measured using the combustion method. The number and width of the disc's annual rings were measured. In climate studies, temperature and precipitation anomalies were used. In addition to extracting all the morphological characteristics, this research showed that the amount of carbon stored in different organs increases with the woody tissue of the plant, and the amount of moisture in the plant organ decreases. The measurement of annual rings showed that the average growth diameter of the studied oak tree is 3.9 mm. The relationship between temperature anomaly and tree diameter growth data showed that the temperature variable has comprehensive control over the geographical distribution of the oak, and the Q. brantii has a more robust response to temperature instead of precipitation variables.

Urban resilience refers to the capacity of an urban system, over both temporal and spatial scales, to maintain or rapidly return to desired past functionalities in the face of disruptions or changes. Climate change essentially refers to the warming of the Earth's surface caused by the accumulation of greenhouse gases in the atmosphere. Urban ecological resilience refers to the capacity of ecological systems within cities to absorb disturbances and maintain necessary and intrinsic feedbacks, processes, and structures. Climate resilience is a subset of urban ecological resilience, denoting a city's potential to address problems arising from sudden weather phenomena and hazards influenced by climate change. Mitigating climate change focuses on five key factors: urban form, construction, artificial environment, urban infrastructure, transportation, and carbon production. Our research aims to contribute to current knowledge and deeper understanding and better identification of climate change and its effects on human life and urban climate quality, utilizing the features of urban green infrastructure, particularly in Tabriz city. We intend to report the effects of climate change and examine the components of resilience using previous studies by evaluating climatic elements. In this study, we employ the Park Cooling Effects method on Land Surface Temperature (LST) using urban green infrastructure. As an example, we sampled from the Bagh-e-Fajr in Tabriz, located in the city center. We have concluded that the presence of green spaces and urban green infrastructure plays a significant role in climate resilience and reducing land surface temperature.

Today, metropolises play a very important role in environmental pollution, increasing population is associated with increasing consumption of fossil fuels and energy resources, which increases greenhouse gas emissions into the atmosphere. The effects of increasing greenhouse gases with the occurrence of greenhouse phenomena cause climate change. Due to the high energy loss in residential buildings, The purpose of this study is to select an appropriate solution to optimize the building and reduce energy consumption in this sector.

In this research, first, the annual energy consumption of a type of 8-storey residential building in Tabriz was simulated using Energy Plus software. Then, the annual energy consumption of the building was simulated with the weather conditions of two different climates of Yazd and Rasht to compare the energy consumption of the building in all 3 cities. Then, with JePlus simulation software, the energy consumption of different building modes (orientation, position, temperature, climate) was simulated in all 3 cities to study the behavior of the building in terms of energy consumption. Finally, the amount of heating and cooling energy consumption of the building was selected as the target functions and optimized by JePlus + EA software.

According to the variables defined in the input of JePlus software, 432 energy consumption modes were obtained for the building. And according to the selection of heating and cooling energy consumption of the building as target functions, optimization was done by JePlus + EA software. The optimization results showed that according to the same parameters considered for all three climates, building energy consumption in Rasht has decreased by 16%, Yazd by 14% and Tabriz by 12%.

The results showed that if the building is built in the right direction and position according to the type of climate and weather conditions (for sunlight, temperature, humidity, etc.) and the heating and cooling temperature inside the building is set to comfort, The energy consumption of the building is also significantly reduced As a result, the share of each building in the amount of carbon dioxide emissions into the atmosphere, which is the most effective gas in climate change, is reduced.

An examination of the trend of climate data recorded in the past decades, as well as the output results of all climate models predicting the future climate, indicate the occurrence of negligible changes in the global climate. Therefore, long-term forecasting of climate variables has received much attention. In order to predict the climatic parameters in Evan Lake, downscaling of general circulation models (GCMs) was used by using the LARS-WG model. The General Circulation Model (GCM) is the most current method by using in climate change studies. They are a key to understanding changes in climate; Although GCMs are imperfect and uncertain. The LARS-WG model was implemented to predict climatic parameters and the necessary analyzes were performed on its results. After selecting the general circulation model and the scenario more in line with the climatic conditions of the region, the outputs of the selected model were compared with the base period to determine the trend of their changes. The results show a decrease in average rainfall (39.9 mm), an increase in minimum and maximum temperatures (0.4 ° C) and an increase in the number of wet days (7 days) and the number of frost days (5 days). Also, the number of dry days (7 days) and the number of hot days (5 days) will decrease in the climate period 2030-2020.

The increase of greenhouse gases and the resulting increase in temperature have caused the balance of the earth's climate system and climate changes in most areas of the earth. Therefore, adapting and dealing with climate changes in the water resources sector along with reducing their reflection should be seriously addressed as part of a comprehensive regional response to the vulnerability caused by climate change. In this study, using LARS-WG exponential microscale software and the HadCM3 oceanic atmospheric general circulation model in the form of different scenarios defined in the fourth IPCC report (basic scenarios), including scenario A1, A2, B1, B2, which are more related to regional issues. And the world is concerned from an economic and environmental point of view, the amount of temperature changes and precipitation in the next 100 years of Bashar river basin was predicted. Then the fifth report scenario (RCP) was used and the results were compared with the basic scenarios. The results showed that in both scenarios in the coming period, we will face a large increase in average air temperature, but the decrease in precipitation will not be significant. In the climate change scenario section, RCPs until the end of the 21st century indicate an increase in temperature and a decrease in precipitation in the coming years. The amount of temperature changes in RCP2.6 was estimated between 3 and 13% and in RCP8.5 between 4 and 14%; This increase in temperature on a large scale increases evaporation and prolongs drought periods.

According to the United Nations definition in 1986, food security is defined as the access of all people to adequate food at all times to maintain a healthy body(FAO Stat 2014). According to this definition, food availability, access to food and sustainability in food intake are the three main pillars(Argent 2019). Food safety and food safety are now addressed in development documents and used by officials. Food security is the access of all members of a society to adequate and healthy food for a healthy and active life at all stages of life, and household income is an important factor in ensuring food security in a social system(HLPE 2013; Development 1995). In recent years, unsustainable agricultural system has led to instability in production and.

One of the most important international instruments to deal with climate change is the Paris Agreement 2015. For over three decades, states have begun long-term talks and negotiations on climate change, which is always on the international agenda. One reason for not concluding an international instrument is that states are not willing to adopt binding commitments on mitigating Green House Gas emission. The failed experience of the Kyoto Protocol 1997 reflects this approach. The piece analyzes the nature of states obligations in the Paris agreement on climate change. This research is based on a legal inductive analysis method. According to this method, the Paris Agreement and some related legal instruments on climate change have been analyzed and assessed. This article while identifies various defining elements of legal character of the Paris Agreement, illustrates that even though the Paris Agreement is an “International Treaty within the meaning of the Vienna Convention on the Law of Treaties” which contains a mix of hard, soft and non-obligations is an important step forward to address climate change, but still has legal and normative inefficiencies.

As climate change has shifted from a marginal issue to a global priority, it has been nearly three decades since the United Nations brought together most of the countries on Earth for the Global Climate Summit, called the COP. The purpose of this study was to investigate the goals and achievements of COP26 and its impact on Iran's macro decisions.

This study was a study on past COPs and COP26. In this regard, previous and current articles were studied along with the lectures and achievements of the COPs, and the course and evolution of this summit, its strengths and weaknesses, and its results were studied. Finally, the impact of this summit on Iran's decisions has been analyzed and some suggestions have been made to improve the policy-making process in Iran.

Given that most power plants in Iran and the steel industry typically use fossil fuels as sources of input energy, the issue of reducing carbon emissions from industries using renewable energy and the use of global aid to help reduce emissions It will have greenhouse gases.

Fields of work inside and outside Iran are in two parts: mitigating and adapting to climate change, and in this regard, there are several international organizations for the allocation of financial assistance.

Today, climate issues threaten the security of the world. Security that is necessary and vital in all fields and for all human beings. Therefore, the ultimate goal of this study is to identify the important and effective factors of climate change in Iran's national security in order to identify and categorize these factors to provide the basis for future measures. The present research is applied in terms of method, descriptive-analytical and exploratory (due to the nature of identifying factors) and in terms of the purpose of doing it. The research data was collected by 10 experts using the snowball method and structural-interpretive modeling (ISM) and MICMAC analysis methods were used to analyze them. According to the research findings, among the first 18 factors of climate change affecting international security were identified, 13 of them are considered more related to national security by experts, and among them, 4 factors are temperature increase, decrease in rainfall, drought and drought. The emergence of water resources with high penetration power and low dependence were identified as key factors affecting Iran's security. These factors act as the structural cornerstone of the system and in order to fundamentally change the performance of the system, they must be emphasized in the first place. In emphasizing these factors, one should not neglect other factors. Because climatic factors are interconnected in a chain and a lack of attention to this issue can lead to other climatic damage and threaten internal and external security.

Today one of the issues and essential crises of human societies is incidence of dust phenomenon. Therefore, in researches, the dust concentration has been compared in relation to climatic variables in Sanandaj, Khoramabad and Andimeshk cities located in different geographical areas in the western half of Iran.

Inactive sampling was done for measuring dust density. Menkendal test and Pierson cohesion were done for assessment of changes process and their relation with some meteorology parameters.

Results showed that the most average density of dust in Sanandaj, Khoramabad and Andimeshk cities were (1.45±0.48, 1.14±0.84 & 1.65±1.07) mg to m2. Checking changes process of dust density showed that Sanandaj station has decreasing process in meaningful level 95 percent (P-value=0.047) between different station. Results of cohesion assessment among dust amounts in 3 stations with metrology parameters showed that in Sanandaj station there was positive relation between dust density and temperature average (p < 0.05, r = 0.61), but there was negative relation between dust density with comparative damp (p < 0.05, r = 0.71) and downfall (p < 0.05, r = 0.61) In Khoramabad (p < 0.05, r = 0.61)  and Adimeshk (p < 0.001, r = 0.72) stations there was positive and meaningful relation between dust density and wind speed. Discussion and

By these findings it can be concluded that dust amounts in different areas depends on geographical condition, topography requirements, continental, metrology parameters and also their origins are various.

In the present study, it has been tried to investigate the climate change effect between current and 2050 on three critically endangered lizards in Iran. For this purpose, three species has been selected Phrynocephalus horvathi, Eremias pleskei, Darevskia kopetdaghica that distributed in northwestern and northeastern part of Iran. Ecological niche modeling indicated that current distribution range of all three species is relatively smaller than predicted models, but during 30 years ahead (till 2050) these suitable areas will be decreased about 50% for E. pleskei and 30% for Ph. horvathi or more than 50% for D. kopetdaghica. Minimum temperature of coldest month and coldest quarter are the most important factors for this variation. Increasing the global warming for next 30 years (till 2050) will change the temperature in different seasons and this event may have direct effect on the lizards that categorized as cold blood animals. Conservation management and evaluation the protected areas can prevent the extinction of animals in face of climate change effects. However, increasing the public awareness about the importance of biodiversity conservation is essential.

Distributional range shift of Amphibian populations especially toads are tightly related to enviromental changes and their survival are threatened by ecological and anthropogenic factors. Talysh toad Bufo eichwaldi occurs in a limited area through the southern margin of the Caspian Sea including north Iran and the southeast of Azerbaijan and has recently considered vulnerable by IUCN Red List of Threatened Species. In this study, 52 occurence records and 20 bioclimatic variables were used for modeling of habitat suitability of B. eichwaldi using maximum entropy algorithm implemented in MaxEnt software package. The results showed that Mean Temperature of Coldest Quarter, Temperature Seasonality, Minimum Temperature of Coldest Month, and Precipitation of Coldest Quarter are the most important predictors for B. eichwaldi suitable habitat. The MaxEnt model indicted that the habitat of B. eichwaldi has been fragmented in the Hyrcanian forest of the south Caspian Sea, which may cause its populaton decline. It is deduced that distributional range of B. eichwaldi in the south of the Caspian Sea experienced contraction due to climate change and human interference comparing to last decades indicating need for conservation programs to protect the Talysh Toad population in the Hyrcanian forest.

Concern about climate change and its effects on various aspects of human life in general and agricultural production in particular is growing. Therefore, the main purpose of this study is to assess and predict of climate change induced temperature and precipitation of Kermanshah township.

The calibration and validation of the HadCM3 model was performed 1961-2001 of daily temperature and precipitation. The data on temperature and precipitation from 1961 to 1990 were used for calibration whereas data from 1991 to 2001 were used for model validation. SDSM version 4.2 as a downscaling model used to downscale general circulation models to station scales.  

 The least difference between observed data and simulation data during calibration and validation showed that the parameter was precisely modeled for most of the year. This study under A2 scenario, three time periods (2020, 2050, 2080) were simulated.  

According to our simulated model, precipitation showed a decreasing trend whereas temperature showed an increasing trend. The result of this study can also be used as an optimal model for land allocation in agriculture.

Climate change is recognized as one of the largest threats to biodiversity and is expected to result in shifting species distributions and increasing extinction risk of populations that are unable to adapt or relocate to suitable habitats. In the present study, habitat suitability of the yellow-spotted mountain newt was modeled to identify the current suitable habitats, to predict the expansion or contraction of the distribution of the species under future climate change scenarios, and to determine the main environmental variables.

The studied species inhabit 57 highland streams of the Zagros Mountain range in western Iran and eastern Iraq. In the present study, species distributions were examined using the maximum entropy model (MaxEnt) for the current and the future (2050 and 2070) climate projection under two optimistic (RCP2.6) and pessimistic (RCP8.5) scenarios.

Based on the results, precipitation of the coldest quarter (BIO13) was the most percent of contribution to predicting species distribution. Comparison of suitable habitat areas in the current and future climate conditions showed that suitable habitats area for the species will not significantly decrease under the optimistic (RCP2.6) scenario in 2070 and an increase was also observed in 2050. Although, a reduction in suitable habitats area (more than 50%) was observed in 2070 under pessimistic (RCP8.5) scenarios. The results of the model supported the hypothesis that due to future climate change, the species distribution range is likely to be conserved in the refugia located in the center and south of the distribution range and by shifting to higher altitudes.

Results obtained from the current study supported the hypothesis that the Zagros climatic refugia play an important role in conserving populations as well as habitats suitable for the Yellow-spotted mountain newtduring climate change.

The cultivation of landraces that are resistant to environmental stresses, pests and plant diseases and have a less need for fertilizers and toxins is important for Increasing access to healthy and nutritious food and tackling climate change that has endangered food production in the contemporary world. In this regard, the native knowledge of people who are traditionally engaged in agriculture is important because it guides the researchers to make appropriate decisions against climate change. This manuscript based on the findings of research to explore the indigenous knowledge of cultivation of landraces among rural women of East Azerbaijan. The research method is qualitative and data collection was done by semi-structured interviews with farmer women. Data analysis by thematic analysis shows that important factors it takes the form of social and economic structures. The results indicate that the combination of the three issues of gender, climate change and agricultural production can lead the agricultural sector to more successful policies to encourage farmers to cultivate landraces and preserve native seeds.

Cannibalism is an aggressive behavior in which the living organism eats whole or part of its body. In amphibians, cannibalism is done by feeding on its own eggs or larvae. The increase in temperature resulting from global warming, by affecting on the rate of intraspecific interaction and intensifying water level fluctuations and change in density, can alter the rate of cannibalism with a high coefficient in amphibian populations. In this study, independent and interactive effects of temperature (high and low), water level (hydroperiod) (high, low, and decreasing water levels), and density (low and high) factors on the cannibalism of Levant green frog Pelophylax bedriagae larvae was investigated in within 10 months. By considering the independent effect of the factors, the highest rate of cannibalism was observed in high temperature (56.6%), low water level (47.5%) and low density (53.33%). Due to the interactive effect, the highest percentage of cannibalism (including biting and whole body cannibalism) was recorded in the high temperature/low water level/low density treatment with 90%. In contrast, the lowest rate of cannibalism was recorded in two treatments: low temperature/low water level/low density, and low temperature/high water level/low density with 20%. The results of study showed that temperature and density had significant independent effects on the cannibalism but water level fluctuations are not significant. Also, interaction of three factors included temperature, water level and density had a significant effect on the rate of cannibalism.

Although the effects of climate change are threatening to the living conditions of a large part of the world, different groups of activists have failed to improve the climate regime. It is natural that those countries which are more vulnerable to climate change should find some ways to improve the climate by using both legal methods and other less formal methods such as identifying climate change as a security and environmental problem. Climate change and global warming are regarded as two factors, which play a significant role in threatening human security since food shortages, water scarcity, environmental degradation, poverty, disease outbreaks, and mass migration can separately lead to national security, which will undermine and contribute to the failed government scenario. In the domestic and global arena, the security of the modern government becomes meaningful with respect to superior power, and the society is considered insecure even if it faces with a lack of threats. In the modern national security discourse, we see an increase in security software, in addition to its hardware. In the wake of the development of the concept of security, especially the development of a range of national security threats, critics have suggested that civilian threats such as economic and environmental threats can, in turn, be as serious as military threats. Therefore, these threats should be considered as security threats. This article tries to provide an analysis of the impact of environmental dimensions of climate change on national security from the perspective of international environmental law, using an interdisciplinary approach.