Buletin Oseanografi Marina Oktober 2023 Vol 12 No 3:433-446 PISSN : 2089-3507 EISSN : 2550-001 *Corresponding author DOI:10.14710/buloma.v12i3.51455 http://ejournal.undip.ac.id/index.php/buloma Diterima/Received : 04-01-2023 Disetujui/Accepted : 30-08-2023 The Impact and Prediction of Shoreline Dynamics in Pekalongan, Indonesia Muhammad Farras Ayasy 1,2 , Muhammad Helmi 1,2 , Muhammad Zainuri 1,2* , Kunarso 1 , Baskoro Rochaddi 1 1 OceanographyDepartement, Faculty of Fisheries and Marine Science, Universitas Diponegoro Jl. Prof. Jacub Rais, Tembalang, Semarang, Jawa Tengah 50275 Indonesia 2 Center for Coastal Rehabilitation and Disaster Mitigation Studies, Universitas Diponegoro Jl. Prof. Sudharto SH., Tembalang, Semarang, Jawa Tengah 50275 Indonesia Email: muhammadzainuri1962@gmail.com Abstract Shoreline in Pekalongan has changed and impacted land use significantly. This research investigates historical changes in shoreline dynamics and their impact on land use from 2003–2021. This research also examines the trend of shoreline prediction for 2031–2041. Multitemporal SPOT5 and SPOT6 satellite images were used as primer data to detect shoreline and land use changes. The DSAS (Digital Shoreline Analysis System) analyzes the shoreline change and generates shoreline prediction. This research shows that the coastal areas of Pekalongan have been impacted by erosion, with 528.08 hectares of area and 56.33 hectares of accretion. The North Pekalongan sub-district is the worst area hit by erosion. The shoreline has retreated 2405.8 meters with a 353.3 m/year erosion rate. Several areas of land use were heavily affected by erosion trends, such as ponds, rice fields, and open land. Shoreline predictions generated by DSAS were heavily reliant on historical rates of shoreline change dynamics. The predicted area of the shoreline is estimated to retreat 49.9–466.2 meters from the existing position in the next 10 and 20 years. This research is expected to provide information to local governments for evaluating the maintenance and development planning of the coastal area Keywords: Shoreline Dynamic, Shoreline Prediction, DSAS, Land Use, Geospatial Analyst INTRODUCTION Coastal area is a transition area between land and marine ecosystems. Coastal areas can be used for development purposes such as settlement, industry, ports, and tourism; and the presence of natural resources such as fishery, aquaculture, mangrove forests, and coral reefs (Kwong and Gunasiri, 2014). However, the coast constantly adapts to new developments, encouraging shoreline dynamics to have a natural balance (Arief et al., 2011) City and Pekalongan Regency shorelines, which have sandy beach coastal typologies, are constantly changing (Marfa’i et al., 2011). The shoreline dynamic is related to coastal characteristics such as morphology, material, and the processes which directly occur in the shoreline dynamic. These processes include natural factors (hydrodynamic processes), human factors (anthropogenic), and their interaction (Ongkosongo, 1982). On the other hand, the Coastal City area and Pekalongan Regency experience rapid land use development in various sectors each year (Kartika et al., 2019). The shoreline dynamic impacts land use in coastal areas (Kwong and Gunasiri, 2014; Dewi and Bijker, 2019). Therefore, a study that uses multitemporal data to monitor and predict shoreline dynamics and their impact on land use is required. This research also examines the shoreline trend projections for 2031-2041, which are expected to provide data for local governments and can be used for evaluation of management and development planning in coastal area. MATERIAL AND METHODS Study area includes the districts of Siwalan, Wonokerto, Tirto (Pekalongan Regency), and North Pekalongan (Pekalongan City) in Central Java, Indonesia. Primary data includes SPOT5 with a resolution of 5mx5m from 2003 and 2009 and SPOT6 with a resolution of 6mx6m from 2016 and 2021. Secondary data consists of a land use map at