مقالات و نشریات

ادیب روشنی

Investigation of climate change effects on Iraq dust activity using LSTM

Journal: Atmospheric Pollution Research

Abstract

Awareness about the impact of climate change on the change rate of dust phenomenon has become a crucial problem due to public health, climate, and air quality. It has been recognized that the Tigris- Euphrates alluvial plain is the main source of dust storms in the Middle East and southwest Asia. In this work, the effects of different variables, including minimum temperature (Tmin), maximum temperature (Tmax), precipitation (Pr), mean wind speed (MWS), humidity (H), and vegetation (Veg) on dust activity are investigated, and Aerosol optical depth (AOD) was predicted by Long Short-Term Memory (LSTM) from 2021 to 2040. HadGEM3-GC was selected to generate the climatic patterns under Shared Socioeconomic Pathways (SSP2-4.5 and SSP5-8.5) scenarios until 2040. The Long Ashton Research Station Weather Generator (LARS-WG 6) software was used to downscale the General Circulation model (GCM). Moreover, Mann-Kendall and Sen’s slope tests are utilized to assess a significant trend. Tmax, Tmin, Pr, and Veg were determined to predict AOD that had a highly close relationship with AOD (r = 0.865, R2 = 0.752, RMSE = 0.079, and MAE = 0.065). The results indicated that AOD would rise gradually in two upcoming decades with 10.5% and 15.2% related to base period (2000–2020) under two scenarios. Understanding of dust phenomenon of future prospective could help policymakers to provide a better situation of air quality

Groundwater level fluctuations in coastal aquifer: Using artificial neural networks to predict the impacts of climatical CMIP6 scenarios

Journal: Water Resources Management

Abstract

Groundwater resources play a crucial role in supplying water for domestic, industrial, and agricultural use. In this study ACCESS-CM2, HadGEM3-GC31-LL, and NESM3 were selected for validation from Coupled Model Intercomparison Project Phase 6 (CMIP6). In the following, the feedforward neural network was employed to predict monthly groundwater level (GWL) based on the emission scenarios of the sixth IPCC report (SSP2-4.5 and SSp5-8.5) for the next two decades (2021–2040) in the Sari-Neka coastal aquifer near the Caspian Sea, Iran. In this regard, the monthly maximum and minimum temperature, precipitation, and water table of previous month from four piezometers from 2000 to 2019 were used as input variables to forecast GWL. The evaluation of the three GCM models demonstrated that the ACCESS-CM2 provided the best values of the R2 and RMSE with observation parameters. The results of r, R2, RMSE, and MAE were evaluated for the model and indicated good performance of the model. The results also illustrated that under such mentioned scenarios, the mean monthly temperature would rise approximately from 0.1–1.2 °C. In addition, the mean monthly precipitation is likely to witness changes from -10% to 78% in the next two decades. As a result, this seems to lead to improvement and recharge of groundwater level for the near future. The results can help managers and policymakers to identify adaptation strategies more precisely for basins with similar climates

Extreme temperature events in Kazakhstan and their impacts on public health and energy demand

Abstract

Extreme temperature events such as heatwaves are becoming increasingly severe and frequent because of climate change, posing significant challenges to public health and energy infrastructure. This study explores the impacts of extreme temperature events leading to heat-/cold waves on public health and energy consumption in Kazakhstan from 1959 to 2021. The most striking trends in heatwave-related indices emerge in the western and southwestern regions. Conversely, despite heightened coldwave intensity, a decline is noted in their frequency and number. The impact of heatwaves on various health conditions, notably consistent and statistically significant rises in all-cause and cardiovascular mortalities, is observed. Shifts in energy demand are also unveiled with a noticeable spike in cooling-degree days and a reduction in heating-degree days. The mean total energy consumption stood at 552 kWh across the country with an average annual energy generation of ≈8.76 kWh. To gauge the environmental implications, the mean CO2 emissions are estimated at 464 kg per kWh for both heating and cooling purposes. With climate change set to escalate heatwaves, the need for comprehensive health planning is underscored to mitigate their adverse health impacts. Furthermore, transitioning from fossil fuels to green energy sources is crucial to reduce the environmental footprint.

Forecasting the effects of climate change scenarios on temperature & precipitation based on CMIP6 models

Journal: Water and Irrigation Management

Abstract

Climate change has many impacts on all environmental processes and society. In this study, three models selected from Coupled Model Intercomparison Project Phase 6 (CMIP6) including ACCESS-CM2, HadGEM3-GC31-LL, and NESM3 are validated. The best model (i.e. ACCESS-CM2) is selected to simulate the climatic parameters of the Sari Station using the latest emission scenarios called “shared socioeconomic pathways (SSP).” The LARS-WG is adopted for downscaling, and two emission scenarios SSP2-4.5 and SSP5-8.5 are used for two periods 2041-2060 and 2081-2100, respectively. Several statistical tests are conducted including F-test, T-student, Kolomogrov-Smirnov, coefficient of determination (R2), and root mean square error (RMSE) to validate the LARS-WG model. The verification results indicate the efficiency of the LARS-WG model. The Man-Kendal and Sen’s slope tests are adopted to determine the trend of climatic observational parameters. In general, the results show that the average temperature change increases in the range of 1.16-4.09 °C and also the average annual rainfall increases by 24-36 percent. The Sen’s slope results in terms of maximum and minimum temperatures show an ascending trend in this parameter, but it is descending in the rainfall. Since long-term climate change is one of the factors affecting groundwater and surface resources, it is necessary to develop proper management strategies for the future, preserving ecosystems, and adapting humans to these changes.

The Escalating Threat of Heatwaves in Central Asia: Climate Change Impacts and Public Health Risks

Abstract

Extreme temperature events, particularly heatwaves, are intensifying due to climate change and urbanization, posing major public health challenges in Central Asia (CA), where research is limited. Despite the rising frequency and severity of heat extremes, long-term assessments of their health impacts are scarce. This study addresses this gap by analyzing historical and future heatwave trends and associated health risks using multi-ensemble climate models across 700 locations from 1959 to 2100. Bias correction improved GCMs, reducing bias and RMSE by 24% and 14%, respectively. Under SSP2–4.5, projected heatwave magnitudes (HWM) shift from 26 to 31 °C, consistent with historical moderate to severe events. Under SSP5–8.5, HWM increases to 29–36 °C. Turkmenistan is expected to experience ultra-extreme heatwaves in the far future, a pattern not seen in other CA countries. Under SSP2–4.5, Kazakhstan and Uzbekistan show the highest rises in heatwave-related mortality rates, with slopes of 5.432 and 3.021 in the near future, declining to 1.377 and 1.102 in the far future. SSP5–8.5 shows similar but higher estimates, highlighting escalating public health risks. Findings emphasize the urgent need for region-specific climate policies and public health strategies to mitigate the growing burden of extreme heat in CA.

Energy generation and carbon footprint under future projections (2022–2100) of central Asian temperature extremes

Journal: Global challenges

Abstract

Limiting the global temperature rise to 1.5 °C is becoming increasingly difficult. The study analyzed data from 700 locations (1962–2100) to assess climate change impacts on heating-cooling energy and carbon footprint in under-researched Central Asia (CA). Under SSP2-4.5, icing and frost days reduce, while summer days and tropical nights increase. Central Asian countries will see an increase in cooling needs despite the projected decline in heating demands, with Kyrgyzstan experiencing the highest rise in cooling degree days, projected to increase by 132% and 165% in the near-future under SSP2-4.5 and SSP5-8.5, respectively. As a result, cooling energy generation is expected to rise by 39% and 92% under SSP2-4.5 and SSP5-8.5, respectively. However, CO2 emissions for cooling are much lower in Kyrgyzstan and Tajikistan due to their reliance on renewable energy. CO2 emissions in these countries are projected to be ≈10 times lower than in other parts of CA. From 2022 to 2100, cooling-related emissions are estimated to increase by 41% and 80% under SSP2-4.5 and SSP5-8.5, respectively across CA. Urgent adaptation is needed for resilient cities and stable power by expanding renewables, modernizing infrastructure, boosting efficiency, adopting policies, and fostering cooperation.

کامران نوبخت وکیلی

Identification of land subsidence hazard in asadabad plain using the PS-InSAR method and its relationship with the geological characteristics

Journal: Natural Hazards

Abstract

In this study, the permanent scatterer InSAR (PS-InSAR) technique was utilized to monitor land subsidence in Asadabad city and the adjoining plains located in the west of Iran using Sentinel-1A satellite images in the 2015–2018 period. Based on the results, the Bad Khoreh area exhibited the maximum subsidence rate of about 224 mm/year among the examined areas in the county in the selected period. Also, the rate of land subsidence had increased from the urban areas toward the plains. Moreover, the processing of underground water level data of piezometric wells in the study area indicates that land subsidence in Asadabad city and the adjacent plains has a direct relationship with the overexploitation of groundwater resources during the 2015–2018 period. Furthermore, subsurface geology and land subsidence were analyzed based on information gathered from eleven wells with a total depth of 614 m. The examination of borehole logs and profiles demonstrated that the areas composed of fine clay and sand had undergone severer subsidence than those composed of coarse-grained sediment due to the greater consolidation and compressibility of the grain sediment.

Identify suitable artificial groundwater recharge zones using hybrid deep learning models

Journal: Results in Engineering

Abstract

Identifying groundwater recharge zones is crucial for sustainable water resource management in water-scarce environments, such as Kurdistan, Iran. This study evaluated four deep learning models for delineating groundwater recharge zones: Artificial Neural Network (ANN), Convolutional Neural Network (CNN), Gated Recurrent Unit (GRU), and hybrid deep learning Convolutional Neural Network-Gated Recurrent Unit (CNN-GRU). Two datasets were used in this study. The first dataset comprised 10 traditional parameters: elevation, rainfall, soil type, drainage density, land use, topographic wetness index (TWI), flow direction, stream power index (SPI), slope, and curvature. The second dataset enhanced the analysis by incorporating additional parameters related to climate patterns. In addition, two feature selection methods, namely Mutual Information (MI) and Random Forest (RF), were employed to identify the most significant factors. In the end, model performance was validated using Accuracy, Kappa score, Root Mean Square Error (RMSE), F1-score, Confusion Matrix, and Receiver Operating Characteristic curve (ROC). Results demonstrate that the hybrid CNN-GRU outperformed other methods, such as ANN, CNN, and GRU, with an Accuracy of 0.9461 and RMSE of 0.2322 on the 13-factor dataset during validation. The enhanced 13-factor dataset consistently improved outcomes across all models compared to the 10-factor dataset, showing the value of climate factors. Finally, the findings from this study reveal that the hybrid CNN-GRU model with climate factors greatly improves accuracy in identifying groundwater recharge zones.

1- تخمین مدل تقاضای لرزه‌ای برای سطوح خرابی متوسط و زلزله‌های نزدیک گسل پالسگونه

2- شناسایی و تشخیص آسیب جداشدگی در ستون کامپوزیت CFST با استفاده از داده های دینامیکی مودال

3- تخمین بیشینه ی پاسخ سیستم های غیرخطی تحت اثر طیف طرح حوزه ی نزدیک گسل بابه کارگیری روش های خطی سازی معادل

4- ارزیابی قابلیت اعتماد ترکیب بارهای شامل بار باد در آیین نامه بارگذاری ایران

5- برآورد توأم هدایت هیدرولیکی اشباع خاک و تخلخل مؤثر با استفاده از رویکرد مسأله معکوس هوشمند

6- تعیین سطح لغزش بحرانی در ترانشه‎های خاکی با استفاده از الگوریتم ژنتیک

7- استفاده از الگوریتم ژنتیک در تعیین سطح لغزش بحرانی شیب های خاکی

عبدالله اعتصامی

1- طراحی بهینه سیستم تصفیه فاضلاب زیست محیطی براساس مدل شبکه بندی دینامیک در محیط آب

2- بررسی عوامل ترک خوردگی و شکست در کوله های بتنی پلهای یک دهنه دو سر مفصل و نحوه تقویت آنها با استفاده از الیاف های FRP