Northern Coastal Region Research Articles

Prediction of the potential Brazilian distribution for invasive mollusc Melanoides tuberculata (Müller, 1774), including a new record from Northern Coastal Region

The freshwater snail Melanoides tuberculata (Müller, 1774) native from Africa and Asia, recently spreads out over the world. Records of invasive species are extremely important, because it helps in future invasions mitigation. Here, we report for the first time the occurrence of M. tuberculata in a protected area of Northern Brazilian Coast and use predictive distribution modeling to know the potential Brazilian distribution for this species. The gastropod M. tuberculata were collected in the municipalities of Tutóia and Santo Amaro - Maranhão State. According to the results of the predictive map distribution for Brazil, the regions with the highest susceptibility are the northeast, southeast and midwest. Preciptation of month and Isothermalithy were de variables that most contribute to the species’ potential distribution. This species presented high to medium suitability of occurrence in 32 national protected areas. Futher studies are recommended to monitor the growth and dispersion, in order to determine its real impact.

Identifying groundwater characteristics and controlling factors in Jiaozhou Bay’s northern coastal region, China: a combined approach of multivariate statistics, isotope analysis, and field empirical investigations

Explicit identification of hydrochemical processes and their controlling factors within groundwater systems is critical for the sustainable utilization of water resources in coastal urban areas. This study was undertaken in the North Coastal Region of Jiaozhou Bay (NCRJB), located in the eastern part of Shandong Province, China, an area grappling with significant issues of groundwater quality degradation and water scarcity. A total of 105 groundwater samples and 34 surface water samples, collected from 2020 to 2024, were analyzed and studied using various hydrogeological tools, multivariate statistical analyses, and water quality assessment methods. These include the Piper diagram, hydrochemical facies evolution diagram (HFE-D), Principal Components Analysis (PCA), correlation analysis, stable isotope analysis, Water Quality Index (WQI), and USSL diagrams. The results indicated that all surface water and pore groundwater samples were categorized as Na-Cl type, exhibiting high Total Dissolved Solids (TDS) and Electrical Conductivity (EC) values, characteristics that render them poor to unsuitable for drinking and irrigation purposes. The fracture groundwater is predominantly of the Ca-Na-Cl mixed type, with average suitability for irrigation and a limited proportion (22.5%) deemed suitable for drinking. Seawater intrusion, primarily through the surface water system, and the impact of human activities were identified as the predominant controlling factors con-tributing to the degradation of the local groundwater environment. Field empirical investigations further validated the results derived from hydrogeological assessments, multivariate statistical analyses, and isotopic approaches. The long-term shifts in hydrochemical properties, along with the latent threat of seawater intrusion, exhibit an upward trend during the dry season and show a certain degree of mitigation during the wet season. This study highlights that field investigations, in conjunction with hydrochemical tools, multivariate statistical analyses, and stable isotope analysis, can successfully furnish reliable insights into the predominant mechanisms governing regional groundwater evolution within the context of long-term and intricate envi-ronmental settings.

Dynamics of Feline Sporotrichosis in Espírito Santo, Brazil: Impact of Urbanisation.

Sporotrichosis is a chronic infectious mycosis caused by traumatic implantation of Sporothrix spp., which poses a significant challenge to public health because of its zoonotic nature. It affects humans and other animals, particularly cats. This study investigated epidemiological trends and spatial distribution of feline sporotrichosis in Espírito Santo between 2017 and 2022. This study collected diagnostic data on sporotrichosis from the Veterinary Pathology Laboratory and Center for Infectious Diseases in Espírito Santo from 2017 to 2022. Statistical analyses were performed using STATA and spatial analyses were performed using ArcGIS software to create maps and identify hotspots. Kernel density estimation and directional mean statistics were applied to visualise the disease concentration and transmission trends. The results showed a significant increase in feline sporotrichosis cases in Espírito Santo from 2017 to 2022, with hotspots identified in urban and densely populated areas. Anchieta, Aracruz and Vila Velha reported the highest numbers of cases. Spatial analysis indicated a spread towards the central and northern coastal regions. This study highlights the growing threat of feline sporotrichosis in Espírito Santo, Brazil, particularly in densely populated urban areas. This underscores the urgent need for comprehensive public health strategies that address urbanisation, human-animal interactions and managing stray cat populations. Effective control measures and enhanced surveillance are crucial to mitigate the spread of this zoonotic disease. Importantly, this study provides valuable insights into the epidemiology of sporotrichosis in Brazil and offers a framework for other regions identified as emerging hotspots that face similar challenges.

Detrital zircon provenance record of the northern shelf in the Rakhine Basin, Bay of Bengal

The Cenozoic strata in the Rakhine Basin play a crucial role in hydrocarbon exploration; however, the provenance of these sedimentary rocks remains poorly investigated. In this study, we employed detrital zircon geochronology and geochemistry in the northern Rakhine shelf to investigate the provenance of sedimentary rocks and, combined with the previous studies, to identify their spatial and temporal variations and to elucidate the provenance evolution since the middle Miocene. The geochemical results of the zircons indicate that the primary source rocks of the sedimentary rocks are magmatic and metasedimentary rocks, particularly those of continental arc and post-collision granites. The origin of these rocks can be attributed to the Gangdese arc magmatic belt in the north, as well as the Indo-Burma Ranges in the east. The sedimentary rocks in the northern Rakhine yield zircon U-Pb age peaks primarily at 0-150 Ma, 400-600 Ma, 600-1000 Ma, and 1600-2100 Ma, with minor populations at 150-400 Ma and >2100 Ma. The detrital zircon provenance study shows that the zircons in the Miocene sedimentary rocks were primarily derived from the paleo-Brahmaputra River, with contributions ranging from 68.7% to 77.0%. During the Pliocene, the paleo-Brahmaputra River and the Chittagong-Tripura Fold Belt were the most significant sediment suppliers. Since the early Pleistocene, the northern Rakhine coastal region has played a significant role in their composition. The Brahmaputra River was the predominant contributor to upper Pleistocene rocks, and the Rakhine coastal region’s contribution to the shelf intensified throughout the Pleistocene. In conjunction with regional tectonic evolution, our study underscores the importance of the Indian Plate subduction as a pivotal factor influencing the provenance transitions in the northeastern Bay of Bengal.

GIS-Driven Method for Site Feasibility Assessment of Large-Scale Solar Thermal Seawater Desalination: An Australian Case Study

Concentrated solar power (CSP) plants can be coupled with seawater desalination via Multi-Effect Distillation (MED) by recovering the cycle’s ‘free’ waste heat. However, project viability, based on the payback period, is contingent upon systematic consideration of climate variability, topography, water resources, markets, and natural hazards. This study describes a data-driven method for screening and then selecting optimal sites in Australia by integrating a Geographic Information System (GIS), System Advisor Model (SAM), MATLAB program, and a Multi-Criteria Decision-Making (MCDM) model. Results for potential sites based on only climate, topography, water resources, markets, and infrastructure identify approximately 2.13×105 km2 of land are suitable, granularly mainly located in the north-west and the south coastal regions with high solar resources (average direct normal irradiance (DNI) > 6 ). These regions encompass 56,000 km2 and 25,100 km2 of suitable areas, respectively, with potential payback periods as low as 12.2 years and 14.0 years. Queensland's northern coastal regions also show promise with a potential payback period of 13.4 years, but the suitable area is only 2,070 km2 due to the marine protection areas in the eastern coastal zone. New South Wales faces hurdles due to topography and lower solar resources. Model results were consistent with the development of CSP installations in Australia, particularly, the Aurora facility in South Australia. This study provides a precise delineation of CSP-MED integration regions in Australia through the multi-dimensional analysis, offering insights into payback periods, and quantifying variable impacts on project geographical, technical, and economic feasibility.

Seasonal Predictability of Bottom Temperatures Along the North American West Coast

AbstractBottom Temperature anomalies (BTA) along the North American West Coast strongly influence benthic and demersal marine species. However, to date seasonal BTA forecast efforts have been limited and sources of BTA predictability largely undiagnosed. Here, an empirical model called a Linear Inverse Model (LIM), constructed from a high‐resolution ocean reanalysis, is developed to predict North American West Coast BTAs and diagnose sources of predictive skill. The LIM is considerably more skillful than damped persistence, particularly in winter, with anomaly correlation (AC) skill values of 0.6 at 6‐month lead. Analysis of the LIM's dynamics shows that elevated BTA forecast skill is linked to developing El Niño‐Southern Oscillation (ENSO) events, driving predicted BTA responses whose peaks occur at longer leads with increasing latitude. Weaker ENSO‐related signals in the northern coastal region still yield high BTA skill because noise there is also weaker. Likewise, the LIM's forecast signal‐to‐noise ratio is highest for bathymetry depths of ∼50–150 m, maximizing forecast skill there. Together, these predictive components lead to “forecasts of opportunity” when LIM anticipates especially high prediction skill. For the top 20% of events identified by the LIM as the forecasts of opportunity, 6‐month lead BTA hindcasts have AC skill averaging 0.7, while the remaining 80% hindcasts have mean skill of only 0.4, suggesting that the LIM can leverage ENSO‐related predictability of BTA to produce skillful forecasts.

Empowerment of Digital Technology for the Resilience of the Logistics Industry: Mechanisms and Paths

Digital technology, acting as an engine for industrial development, propels the rapid integration of data elements and the swift iteration of digital logistics technology, significantly enhancing logistic resilience. Exploring the impact of digital technology on the resilience of logistics helps strengthen the latter’s ability to withstand external shocks. Based on the correlation between digital technology and the resilience of the logistics industry, this study measured their levels in 275 Chinese prefecture-level cities from 2011 to 2020, showing that the former significantly improved the latter, a conclusion which remained valid after robustness tests. The mechanism analysis results showed that promoting industrial collaborative agglomeration was an important part of this process, while the threshold model analysis found that the impact on resilience had nonlinear characteristics. The heterogeneity test results showed that digital technology had a significant resilience-promoting effect in the eastern and northern coastal regions, as well as in the middle reaches of the Yellow and Yangtze Rivers. Accordingly, it is necessary to accelerate digital technology integration with the logistics industry and formulate differentiated development strategies. This study provides a theoretical foundation for exploring the relationship between digital technology and logistics resilience, as well as policy recommendations.

Preliminary insights of the genetic diversity and invasion pathways of Cedrela odorata in the Galapagos Islands, Ecuador.

Cedrela odorata is considered the second most invasive tree species of the Galapagos Islands. Although it is listed in CITES Appendix II and there are population losses in mainland Ecuador, in Galapagos it is paradoxically a species of concern due to its invasive potential. Genetic studies can shed light on the invasion history of introduced species causing effects on unique ecosystems like the Galapagos. We analyzed nine microsatellite markers in C. odorata individuals from Galapagos and mainland Ecuador to describe the genetic diversity and population structure of C. odorata in the Galapagos and to explore the origin and invasion history of this species. The genetic diversity found for C. odorata in Galapagos (H e = 0.55) was lower than reported in the mainland (H e = 0.81), but higher than other invasive insular plant species, which could indicate multiple introductions. Our results suggest that Ecuador's northern Coastal region is the most likely origin of the Galapagos C. odorata, although further genomic studies, like Whole Genome Sequencing, Rad-Seq, and/or Whole Genome SNP analyses, are needed to confirm this finding. Moreover, according to our proposed pathway scenarios, C. odorata was first introduced to San Cristobal and/or Santa Cruz from mainland Ecuador. After these initial introductions, C. odorata appears to have arrived to Isabela and Floreana from either San Cristobal or Santa Cruz. Here, we report the first genetic study of C. odorata in the Galapagos and the first attempt to unravel the invasion history of this species. The information obtained in this research could support management and control strategies to lessen the impact that C. odorata has on the islands' local flora and fauna.

A new solar-wind complementarity index: An application to the climate of Morocco

Energy complementarity is a promising approach in the realm of renewable energy systems, enabling the integration of multiple energy sources to achieve a stable and sustainable power supply. This paper presents a comprehensive solar-wind complementarity study encompassing all regions of Morocco. A novel method for assessing complementarity is introduced, utilizing a fluctuation approach that classifies the power output of each source based on the median and the standard deviation. The classifications of both solar and wind sources are then combined to establish a basis for complementary classification, categorizing each day as complementary, non-complementary, low-complementary, or concurrent for both sources. An innovative complementarity index is proposed, ranging from 0 to 1, with values closer to 1 indicating high complementarity. This index is applicable to any location and is used to generate maps illustrating solar-wind complementarity. Additionally, dominance metric is derived from this approach that indicates which source is most likely to complement the other source. The results reveal that temporal complementarity is high in the internal Northern regions reaching indices above 0.7, followed by the Northern coastal regions with indices that range between 0.6 and 0.7. The lowest complementarity occurs in the South with indices below 0.6. Additionally, the complementarity plots that displays the monthly indices reveled, for most regions, that complementarity maintains certain level except in the summer where it peaks or drops. The solar dominance is higher in the South reaching above 60 %, even though the wind potential is important in those regions. For spatial complementarity, two locations were considered and the method is applied for four scenarios: solar-wind, wind-solar, solar-solar and wind-wind. Results favor all the combinations except for the solar-solar scenario. The suggested index yields similar results to Kendall's tau correlation. The negative correlation index indicates high complementarity when positive and a low complementarity when close to −1. For this approach, it is not limited to the degree complementarity but can describe other states of complementarity and its frequency of occurrence compared to other states. This provides additional insights compared to the commonly used correlation methods. The proposed method contributes to a more profound understanding of complementarity between two energy sources.

The zoning of flood disasters by combining tidal flood and urban flood in Semarang City, Indonesia

Semarang City, situated along the northern coastal region of Java Island, Indonesia, grapples annually with the dual challenges of tidal flooding and urban inundation. Establishing a comprehensive flood disaster zoning for both tidal floods and urban inundation to identify priority areas for effective flood mitigation and reducing disaster risk. This study aims to assess the potential inundation of tidal floods, urban floods, and their combined impact on Semarang City, using an integrated approach that combines Geographic Information System (GIS) technology with the Analytic Hierarchy Process (AHP). By leveraging data from Digital Elevation Model Nasional (DEMNAS), Google Earth, Rupa Bumi Indonesia (RBI) maps, and the Open Street Map (OSM) database, we obtained elevation, landcover, distance to the river, buildings, and administration data, which were used as criteria in the analysis. The research findings unveil three distinct flood inundation scenarios within Semarang City: tidal floods, urban floods, and a combination of both. Each scenario is categorized into low, medium, and high levels of inundation, providing a granular assessment of flood risk across the city. Importantly, the study extends beyond spatial analysis to evaluate the impact of inundation on affected buildings. The results indicate that the area inundated by the combination of tidal and urban floods is as follows: 86.87% high inundation, 13.12% moderate inundation, and 0.01% low inundation.

Study on Regulatory Authority Guidelines for Fostering Affordable Housing Clusters in the Northern Coastal Region of Tamil Nadu, India

Study on Regulatory Authority Guidelines for Fostering Affordable Housing Clusters in the Northern Coastal Region of Tamil Nadu, India

Examination of constraints and recommendations in maize production and marketing in the northern coastal region of Andhra Pradesh through Garrett’s ranking method

Examination of constraints and recommendations in maize production and marketing in the northern coastal region of Andhra Pradesh through Garrett’s ranking method

Digital Literacy Skills of Elementary School Teachers on the North Coast of East Java

The purpose of this study was to assess the proficiency of teachers in the northern coastal region of East Java in the area of digital literacy. The researchers employed a qualitative research methodology, specifically utilising a phenomenological study design. Elementary school instructors are the target audience for studying digital literacy. The findings of this study concerning the digital literacy of primary school educators are highly favourable. The study found that there are eight indicators of digital literacy for teachers. These indicators include proficiency in operating digital media, creativity in digital spaces, collaboration in digital space, effective communication, information search and selection skills, critical thinking and content evaluation abilities, alignment of social and cultural understanding with digital spaces, and implementation of internet security measures.

Environmental characterization and cartographic modeling of wild plant habitats at the northern coastal zone of Egypt

Assessing natural vegetation through conventional methods faces considerable constraints, such as limited geographical scope, reduced precision, a lack of historical data, high expenses and time demands. The study aims to use environmental and spectral data to identify and map natural vegetation and plant species along the Mediterranean coast of Egypt. This involves employing spatial analyses and cartographic modeling techniques, marking an initial effort in this endeavor. To fulfill this aim, a total number of 70 wild plant habitats were surveyed and sampled for further laboratory identification of plant species. Multispectral and thermal bands of Landsat imagery were processed to generate land cover map, as well as calculate Normalized Difference Vegetation Index (NDVI) and Land Surface Temperature (LST) to be integrated with the naturally grown plants in a cartographic model to predict the wild plant habitats. Coastal wild plant habitats were sparsely located and associated with a vegetation density ranging from 0.096 to 0.280 with an average of 0.167. Besides, the LST of these habitats fluctuated from 30.559 to 38.652 with an average of 34.361°C. Although the wild plant habitats at the Northern coastal region of Egypt are similar in environmental and climatic conditions, there are variability in NDVI and LST of each single habitat (pure or mixed). On the other hand, the lowest LST were associated with Erodium laciniatum/Rumex pictus and Erodium laciniatum habitats reporting 30.559 and 30.741°C, respectively. However, Lotus halophilus mixed with Ifloga spicata habitats reported the highest LST (38.652°C). The high vegetation density is mainly characterized by low LST which indicates the mixed wild plant habitats. The developed cartographic model showed a narrow strip along the Mediterranean region as highly suitable habitats for wild plant growth. The model can be used to map pure and mixed habitats of various wild plants with an accuracy exceeding 90%. The model was applied for mapping Arthrocnemum macrostachyum showing that the middle coastal region is most suitable for its growth. It’s recommended to integrate remotely sensed data with spatial analyses for the environmental analyses of natural plants. Present findings support researchers and scientists interested in environmental, botanic, and medical studies.

An application of 1D convolution and deep learning to remote sensing modelling of Secchi depth in the northern Adriatic Sea

ABSTRACT This paper presents a novel approach for predicting the water quality indicator – Secchi disk depth (ZSD). ZSD indirectly reflects water clarity and serves as a proxy for other quality parameters. This study utilizes Deep Neural Network (DNN) trained on satellite remote sensing and measured data from three sources: two datasets obtained from official agencies in Croatia and Slovenia, and one citizen science data source, all covering the northern coastal region of the Adriatic Sea. The proposed model uses 1D Convolutional Neural Network (CNN) in the spectral dimension to predict ZSD. The model’s performance indicates a strong fit to the observed data, proving capability of 1D-CNN to capture changes in water transparency. On the test dataset, the model achieved a high R-squared value of 0.890, a low root mean squared error (RMSE) of 0.023 and mean absolute error (MAE) of 0.014. These results demonstrate that employing a 1D-CNN in the spectral dimension of Sentinel-3 OLCI data is an effective approach for predicting water quality. These findings have significant implications for monitoring ZSD in coastal areas. By integrating diverse data sources and leveraging advanced machine learning algorithms, a more accurate and comprehensive assessment of water quality can be achieved.

The evolution of epidemics and the publication of epidemic news in the local press: a study in the region of Braga (Northern Portugal)

The periods 1918–1920 and 2019–2021 were characterized by epidemic moments. The COVID-19 pandemic recalled the crises associated with the Spanish flu, exanthematic typhus, and smallpox of the 1920s. However, few works have focused on a comparative task of these episodes in local newspapers. Through the analysis of the daily editions of Commercio do Minho and its successor, Correio do Minho, we fill this gap with this work. It was possible to portray the socioeconomic reach of these pandemics in a community in the northern coastal region of Portugal. Using time series analysis of the number of news items as well as the number of deaths from each of the episodes in the periods 1918 and 1920 and 2020 and 2021 (namely using Autoregressive Distributed Lag models), we conclude that the COVID-19 pandemic exhibited a greater focus on the problem in the local press. Other results made it possible to view the differentiated response of the number of news items regarding each epidemic episode depending on the number of deaths in the population, both between 1918 and 1920 and between 2020 and 2021. Thus, our work came to demonstrate three pieces of evidence in the relationship between news and epidemic processes. Firstly, COVID-19, as an example of the most recent pandemic, brought a reactivity of the local press resulting in a greater number of news, even compared to the number of fatalities. Secondly, the number of news published on epidemic/pandemic issues tends to follow the evolution of the severity of the event—there is more news in the months that follow periods of greater severity of the disease. Finally, the “disappearance” of published news faster in 1918–1920 also reveals a lesser focus that newsrooms perceived on society of that time in the face of the reported pandemic (Nie et al. 2022).

Sintren sebagai Media Dakwah Islam di Cirebon: Perspektif Budaya dan Agama

This research discusses the role of Sintren art in the spread of Islam in the northern coastal regions of Central and West Java during the period of Islamization. The aim is to delve into the contribution of Sintren art as a tool for Islamic preaching, with a focus on the implicit religious messages conveyed in its performances. This study employs methods of analyzing dance movements, song lyrics, and musical instruments used in Sintren performances. The results reveal that Sintren art plays a significant role in facilitating the spread of Islam, with religious messages implicit in these performance elements. The conclusion of this research is that similar to other traditional arts like wayang, Sintren art has played a role in aiding the understanding and acceptance of Islam by the people of that era and has contributed to the preservation of ancestral cultural heritage.

Hydrography of Northern Thermaikos Gulf based on an integrated observational-modeling approach

The Northern Thermaikos Gulf is a semi-enclosed coastal region of the Aegean Sea, characterized by anthropogenic and natural stresses such as intense industrial and agricultural activities, urban outflows, and several river discharges facing severe pollution events. The main motivation of this study is to investigate the prevailing oceanographic conditions of Northern Thermaikos Gulf, which are associated with the quality of the semi-enclosed basin's water masses. The hydrography and the hydrodynamic circulation patterns are revisited, based on the findings of a multi-platform observational study, conducted during a recent annual cycle, from June 2021 until May 2022. The observational findings are supported by a three-dimensional high-resolution hydrodynamic model (Deltf3D-Thermaikos) with updated freshwater input from all important land sources. The physical connectivity between the sub-basins of Thermaikos, the renewal of its northern coastal areas and the seawater quality are strongly related to the variability of wind-induced circulation. Northerly and southerly winds affect the spreading of the nutrient-rich riverine waters, discharged at the west coast of the gulf. The prevailing northerly winds contribute to the southward removal of the polluted sea surface and riverine waters, enhancing the cyclonic circulation around the gulf, allowing the inflow of clearer Aegean Sea Waters along the eastern coasts of the gulf. Northerlies also promote a connectivity pathway between the environmentally stressed Thessaloniki Bay (urban seafront) and the commonly less polluted southeastern coasts of the central basin. Southerlies mainly confine riverine waters in the western and northern coastal regions, weaken the renewal ability of the enclosed basins, and impose the formation of anticyclonic, mesoscale, circulation eddies in the outer and central areas.

Exploring the Impact of Strategic Leadership on the Sustainability of Technology-Centric Companies: An In-Depth Case Study from Colombia's Northern Coast

This research examines the relationships among various elements of Strategic Leadership and Business Sustainability within tech-based firms located in the northern coastal region of Colombia, spanning the years 2015 to 2019. Initially, a correlation assessment was conducted to pinpoint variables that may be linked. Subsequently, a Dickey-Fuller analysis was employed to ascertain the presence of non-stationary variables and to determine if there was any causality between them, using a significance threshold of P ? 0.05. To substantiate the relationships among the scrutinized variables, a dispersion analysis was carried out, supplemented by a review of scholarly works that previously explored the subject matter. It emerged that solely the variables related to human capital and organizational contexts have an impact on the conduct of the social milieu, which acts as a catalyst for the growth of tech-based enterprises. This research is an enriching addition to existing literature, as it dissects the dynamics of tech-centered companies through a lens that transcends conventional narrative frameworks. This study was based on Heidy Rico doctorate research entitled “Incidence of strategic leadership on business sustainability of Technology-Based Companies in the Department of Atlántico”, Universidad Simon Bolivar, Colombia.
 
 Received: 15 June 2023 / Accepted: 09 August 2023 / Published: 5 September 2023

Ionospheric TEC variation over Svalbard archipelago, Norway and assessment of Bilinear interpolated GIM model

The Svalbard archipelago region is a group of islands in the Arctic Ocean, located between the North Pole and the northern coastal region of Norway at high latitudes. The current study focuses on the spatiotemporal distribution of total electron content (TEC) over the Svalbard archipelago region with the ground-based global positioning system (GPS) tracking stations during the years 2020–2022. The spatial ionospheric TEC characteristics from GPS observables and their correlation with the Bilinear interpolated global ionospheric map (GIM) and the latest edition of the international reference ionosphere (IRI- 2020) model are investigated. The results showed that both GPS-TEC and GIM-TEC have minimum ionospheric TEC during the winter season while they have maximum TEC occurrence in the summer and spring seasons with a higher difference of magnitude. We suspect such discrepancy could be due to expected uncertainties in the estimation of GIM-TEC interpolation over the region. The correlation coefficients between GPS-TEC versus GIM-TEC and GPS-TEC versus IRI-TEC showed that they are correlated with an almost equivalent correlation coefficient of approximately 0.76 which is reasonably acceptable but relatively lower than other middle latitude regions. This poor correlation happened because of the diurnal variation in the polar cap region during the summer season which is minimal. Finally, a Multitaper spectral analysis is employed on the frequency spectra of the time-varying periodograms of the four oscillation components. The outcome of the spectral analysis confirms that the first principal component (PC) of GPS-TEC is well correlated with the respective PC of GIM and IRI models. Although the higher order PCs of GIM models remain well-correlated with GPS-TEC, the subdued correlation between IRI model outputs and GPS-TEC suggests further improvements in the IRI model representation with respect to the high latitude characteristics.