Dogal Afetler ve Cevre Dergisi

1-15

Authors: Zehra KOYUNCU; Ömer EKMEKCİOĞLU

The main objective of the current study is to generate a flood hazard map by using the machine learning algorithms hybridized with the geographic information systems (GIS). In this regard, the province of Istanbul, which is the metropolitan city of Turkey, was selected as the focal region within the scope of the study. The class imbalance was tackled through the commonly used random under sampling (RUS) technique in order to create a fair comparison datum line. It is worth mentioning that this is the first time this approach has been used for flood hazard mapping studies in Turkey. Random forest (RF), stochastic gradient boosting (SGB), and XGBoost algorithms were used. The best predictive performance was obtained with the XGBoost algorithm, followed by SGB and RF, respectively. The RF and SGB models showed a 90.67% success rate in determining the inundation points, while the XGBoost model outperformed its counterparts with a 92.00% success rate in determining the inundation points. In this research, the importance levels of the flood triggering variables were further investigated in order to enliven the comprehensibility of the obtained results. Thus, the most important variable was the precipitation, followed by the distance to the drainage network and the number of curves, respectively. Finally, it is suggested that flood vulnerability mapping attempts can be considered as promising approaches against increasing flood incidents over the years.

29-48

Authors: Makber TEKİN; Fahriye MERDİVENCİ

After recent major crises (fire, earthquake, epidemic, etc.), the importance of humanitarian aid logistics has been better understood. The success of the humanitarian aid logistics (HAL) depends on meeting the urgent needs of the victims in the shortest time and with the least amount of resources. Identifiying the factors that affecting HAL and understanding their impact is essential to the success of the process. The study aims to determine the critical success factors that affect the performance of the humanitarian aid logistics, which represents a large part of the cost of aid operations in rescue interventions and distribution of aid materials to minimize losses in disasters in Türkiye. In the methodological part, fuzzy DEMATEL was used, which explains the cause-effect relationships by determining the factors that influence each other and the degree to which they are influenced by each other. As a result of the study, it was concluded that 8 of the 16 critical success factors created with the help of the literature were included in the cause group and significantly impacted the success of the humanitarian aid logistics system in disaster management. Among these factors, it was concluded that coordination and cooperation, organizational structure and distribution of responsibilities, and clarity in reporting and sending information were highly correlated with the highest overall impact and other factors. The results obtained can be helpful for the government, charities, and related NGOs in formulating policies and strategies in logistics management.

68-76

Authors: Ahmet Can KAYA; Veli YAVUZ

In this study, the performance of thermodynamic indices and atmospheric stability parameters in thunderstorm prediction was analyzed for a five-year period between 2018 and 2022 using data from Samsun radiosonde station and aviation observations from Samsun Çarşamba Airport. The thermodynamic indices and atmospheric stability parameters used in the study are Showalter Index (SI), Lifted Index (LI), Severe Weather Threat Index (SWEAT), K-Index (KI), Totals Totals Index (TTI), Convective Available Potential Energy (CAPE), Convective Inhibition (CIN), and Bulk Richardson Number (BRN). Statistical performance tests such as Probability of Detection (POD), False Alarm Ratio (FAR), Miss Rate (MR), Critical Success Index (CIS), Hiedke Skill Score (HSS), and True Skill Score (TSS) were used to measure the success of the indices and parameters in predicting thunderstorm events. The analyses were performed using R and Excel. According to the results, the most successful index in thunderstorm prediction was SI, while the performance of CAPE and BRN parameters was the lowest. Based on all these analyses, it is observed that the majority of thunderstorms occur during the hottest months of the year and the hottest hours of the day. This indicates that most thunderstorms occur due to heating. In some events, the indices and parameters did not even reach the threshold value determined for thunderstorm formation. It is obvious that the prediction accuracy will be further improved if the thresholds of the indices and parameters are optimized for Samsun. Furthermore, evaluating multiple indices and parameters instead of relying on a single index or parameter for thunderstorm prediction will increase consistency and lead to more accurate results.

89-102

Authors: Muhammed BAŞPINAR; Veli YAVUZ

A thunderstorm (TS) is a severe weather phenomenon characterized by intense showers, hail, lightning, thunder, tornadoes, turbulence, and gusty winds. It occurs in vertically developed Cumulonimbus (Cb) clouds due to atmospheric instability and has a spatial resolution (meso-scale) of 1 - 100 km. This phenomenon occurs mainly in spring and early summer in our country due to the uplift and condensation of moist and unstable air masses. However, in recent years, these events have become more frequent during mid-summer, early autumn, and even winter months. In this study, the characteristics of TS events in Istanbul, covering the period from 2013 to 2022, including the warm season (May-September) and the cold season (October-April), were examined, and the atmospheric conditions under which they occur were identified. Aviation observations from Sabiha Gökçen International Airport were used to determine the occurrence of TS events, and data from Istanbul Kartal Radiosonde Station were analyzed to obtain upper-level atmospheric parameters. The occurrence of individual TS events or their association with other phenomena was investigated, and the statistics were presented. The daily, monthly, and yearly analyses of TS events during the period were conducted, and the changes in meteorological parameters for both the warm and cold seasons were statistically presented. Meteorological parameters such as temperature, dew point temperature, wind speed, wind direction, and relative humidity were analyzed for both warm and cold season TS events. Additionally, the average changes in each thermodynamic index and atmospheric stability parameter for hot and cold season oraj events were examined using a total of eight indices and parameters.

113 - 124

Authors: Cafer GİYİK

Disasters are the consequences of natural, technological, or anthropogenic events that directly or indirectly cause physical, economic, social, and environmental losses on people and human settlements, and affect communities by stopping or interrupting normal life and human activities. Though there are several natural disasters, earthquakes cause the most damage in Turkey in terms of damage rate and number of people affected. On the other hand, landslides, floods, rockfalls, avalanches and forest fires also cause considerable damage and economic losses. In Turkey, which is an earthquake-prone country, two devastating earthquakes with a magnitude of 7 Mw in Kahramanmaraş and 7.6 Mw in Hatay Kırıkhan occurred on 6 February 2023. While these earthquakes were effective in Malatya, Kahramanmaraş, Adıyaman, Gaziantep, Şanlıurfa, Diyarbakır, Hatay, Adana, Osmaniye, Kilis and surrounding counties, 50,399 people lost their lives and 1,279,727 structures (independent units) were damaged. The aim of this study is to determine what has been done within the scope of post-disaster temporary shelter applications in disaster areas and which methods were used to create these areas. In the study, temporary sheltering practices in Nurdağı District of Gaziantep province, one of the settlements most affected by the earthquake, were examined. In this context, evaluations were made regarding the qualifications, adequacy level and functions of prefabricated and temporary shelter areas such as tents, containers and masonry structures created in the district.

140 - 154

Authors: Seyran Büşra GÖK; Merve YAVAŞ

The aim of this study is to integrate macro-scale data with micro-scale data by considering the relationship between planning and geology, and to present a locally specific risk model against earthquakes. It is also aimed to develop a coordinated perspective in the planning system for earthquake risk. In Erzurum, one of the cities with high earthquake risk in Turkey, the extent to which the disaster is taken into account in the process of shaping the urban space, especially in new development areas, was investigated. The methodology of the study was based on literature studies related to the multi-criteria decision-making method, which is frequently used in the determination of urban earthquake risks. Based on the criteria of the "Combined Risk Model" used especially by Japan, a Building Collapse Risk Rating Map has been created for Osmangazi Neighborhood, whose development continues with development activities in Erzurum. According to this map, it was determined that 1.39% of the total number of zoning lots in the study area is very low risk, 48.59% is low risk, 41.25% is medium risk, 6.29% is high risk and 2.09% is very high risk. Accordingly, it has been determined that zoning conditions and construction activities in new development areas in Erzurum increase the earthquake risk.

167 - 178

Authors: Cansu BOZKURT; Mahmut FIRAT; Abdullah ATEŞ

Water utilities should regularly monitor and control non-revenue water performance to manage water losses and maintain uninterrupted water services. Effective and sustainable water loss management is crucial for ensuring water, energy and financial efficiency in drinking water distribution systems. In this study, it is aimed to evaluate the water loss management components, analyze the current situation with a realistic approach, and identify the weaknesses and strengths of the administrations and the potential risks they may encounter through the web-based software developed in this study. In this context, in the study, firstly, the current situation components, which express the competence of the administration in terms of personnel, technique, equipment and financials, are analyzed with the 6-stage original scoring matrix developed from 0 to 5 within the scope of the study, reliable and quality data are obtained, and then the three modules work dynamically in an integrated way with each other so that the analysis of measurable, applicable and comparable performance indicators is done systematically. Thus, priority areas that need improvement are identified, short-medium and long-term realistic and achievable targets are defined, and the gap analysis of the administrations is provided with the developed modules. In order to reduce and control the water loss rate and to improve the system performance, the most appropriate indicators and processes are determined by considering the current situation and targets of the administrations. The developed water loss management tool represents the field and provides a holistic approach, taking into account the economic components. At the same time, this tool allows for processes to be carried out quickly and systematically, and provides efficient analysis in water loss reduction activities.

192 - 210

Authors: Redvan GHASEMLOUNIA; Mustafa UTLU

Drought is one of the most important challenges that many countries, especially countries in the Middle East region, are struggling with. Based on this, the study and monitoring of hydrological and drought factors is an important issue that can have a significant impact on management decisions in the field of water resources, especially in crisis management. Therefore, investigating the drought parameters is very important to understand the drought situation of a region. In this study, Alanya region, which is located on the southern coast of Turkey, was selected as a case study for drought analysis. Four drought indices for the selected region including: China Z-Index (CZI), Standardized Precipitation Index (SPI), Modified China Z-Index (MCZI) and Z-Score Index (ZSI) have been investigated. All these indicators have been investigated and evaluated using time scales of 1, 6, 12 and 24 months, the coefficient of determination (R2) has been calculated for each drought index with a different time scale and their results have been compared. The findings of the research showed that SPI and CZI drought indices performed better than other selected drought indices in identifying and effectively tracking drought severity. In addition to the study of dry events, wet events were also investigated, which indicates the presence of consecutive floods in the last years of the studied period in the region. The results indicated similar very dry events for the selected indicators in the 6-month period. Also, the rainfall trend for the period of 2015-2022 was taken into consideration to examine the rainfall of the last eight years. The results show that precipitation has decreased in recent years and has a downward trend in most months of the period in question, and the possibility of flood events due to sudden showers in the region has increased due to the continuation of droughts experienced in the years before 2015. Investigating soil moisture and vegetation for the selected period in the study area is also important for the evaluation of the drought level. Evaluation of the available land (vegetation) cover maps of the years 1975, 1985, 2000, 2010, 2020 and 2022 show that the vegetation cover has weakened over the years, and it has been evaluated as an indicator that the danger of drought in the region has increased.