Land use change in urban areas could not be avoided as consequence of land requirement incensement. The high density of developed land in the central city have pushed the development towards the periphery. This article examines the result of Landsat image analysis using remote sensing (RS) and geographic information system (GIS) technology to monitor green open spaces change to temperature changes in Semarang. Data source which used in this study are Landsat 5 Image in 2003, and Landsat 8 Image in 2015. This uses multispectral classification method with a supervised approach to get land use condition serially (time series). Surface temperature processed based on radiance value in band 6 of Landsat 5 and the value in band 10 and 11 of Landsat 8 TIRS. Temperature changes were seen quite significant in the west side of Semarang City, include Ngaliyan District, Mijen District and Gunungpati District. The change occurs in an average range of 20.75 0 C to 22.07 0 C. Along with the temperature changes, based on image analysis result showed that green open spaces in all of three districts were decreased from 48.75 km2 to 22.98km2. In general, the green open spaces change throughout Semarang City from 15.28% to 9.91% within a period of 12 years (2003-2015).

Abstract-The2 , and second 27,18km 2 . The impact of land use change and population growth is an intrusion. Based on laboratory tests show that Pekalongan city intrusion on high category. The region within distance 500-600m from the coastline has salinity level of 6,7 to 15.5%, 800-900m has a salinity level of 2,9 to 6.6%, 1-1.5km has a salinity level of 1,4 to 2,8. Conclusion, land use change on Pekalongan City rather high, especially shrub, and dry agriculture changes into a settlement and built area. Furthermore, the coefficient correlation between population and built area is high (0,93). These include a significant difference final result of simulation using Landuse Sim with linear approach and consider the expense of population growth influence. Furthermore, land use change on Pekalongan city drives an environmental problem, for instance intrusion.

Land cover changes based on cellular automata for surface temperature in Semarang Regency has increased significantly due to the continuous rise in its population. Therefore, this study aims to identify, analyze and predict multitemporal land cover changes and surface temperature distribution in 2028. Data on the land cover map were obtained from Landsat 7 and 8 based on supervised classification, while Land Surface Temperature (LST) was calculated from its thermal bands. The collected data were analyzed for accuracy through observation, while Cellular Automata - Markov Chain was used to predict the associated changes in 2028. The result showed that there are 4 land cover maps with 5-year intervals from 2003 to 2018 at an accuracy of more than 85%. Furthermore, the existing land covers were dominated by forest with decreasing trend, while the built-up area continuously increased. The existing Land surface temperature range from 20.6°C to 36.6°C, at an average of 28.2°C and a yearly increase of 0.07°C. The temperature changes are positively correlated with the occurrence of land conversion. Land cover predictions for 2028 show similar forest dominance, with a 23,4% built-up area at a surface temperature of 28.9°C. Keywords: Land cover change; Cellular Automata-Markov Chain; Land Surface Temperature Copyright (c) 2021 Geosfera Indonesia and Department of Geography Education, University of Jember     This work is licensed under a Creative Commons Attribution-Share A like 4.0 International License

Semarang City has a low and flat topography in several areas so that it has a high risk of inundation during the rainy season with a spatial distribution in the city center area. In 2022 inundation floods have inundated 877.66 hectares, one of which is in the Tembalang area and its surroundings with a height of around 275 MDPL which occurred in 20 locations with an area of around 33.62 hectares, where the area is the downstream part of the Babon Watershed. The results of the analysis of rain in the Babon watershed area for 20 years show that it is relatively stable, not too much variation, where the results of calculating the rational flood discharge for 2022 with a return period of 2 years are around 25.80 m³/s. Furthermore, the morphometric analysis of the watershed shows that the shape of the Babon watershed is relatively elongated with a circularity ratio <0.50, the density index of the river is 0.25 – 10 km/km² which is in the medium density category with a relatively long Time Concentration (TC) of around 3.2 hours so that it is less thus impacting flooding downstream. The Babon watershed runoff coefficient is affected by land cover conditions, where the interpretation results show that there was a change in land cover from 2002 – 2022 for the area of built-up land which increased by 708.44 hectares and the vegetation area decreased by 486.77 hectares. Analysis of channel capacity shows that there is potential for overflow from existing channels in 7 sub-watersheds which will result in inundation. The conclusion of this study shows that rainfall over the past 20 years has been relatively stable and the morphometry of the watershed has not had much impact on downstream flooding, the main river capacity of the Babon DAS is still sufficient to accommodate the planned flood discharge with a return period of 25 years. So that inundation that occurs is more caused by changes in land cover and drainage capacity in the downstream.

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