Abstract. Urban heat is a natural phenomenon which might caused by human activities. The human activities were represented by various types of land-use such as urban and non-urban area. The aim of this study is to identify the urban heat behavior in Tangerang City as it might threats the urban environment. This study used three types of remote sensing data namely, Landsat TM, Landsat ETM+ and Landsat OLI-TIRS, to capture the urban heat behavior and to analysis the urban heat signature of Tangerang City in 2001, 2012, 2013, 2014, 2015 and 2016. The result showed that urban heat signature change dynamically each month based on the sun radiation. The urban heat island covered only small part of Tangerang City in 2001, but it was significantly increased and reached 50% of the area in 2012. Based on the result on urban heat signature, the threshold for threatening condition is 30 o C which recognized from land surface temperature (LST). The effective temperature (ET) index explains that condition as warm, uncomfortable, increase stress due to sweating and blood flow and may causing cardiovascular disorder.

Cimanuk watershed will be affected directly by the dynamics of Cilutung watershed as one of its tributaries. Cimanuk is one of the watershed areas in West Java Province, that is categorized as a critical potential due to erosion and vegetation damage. This study aims to simulate hydrological conditions and erosion rates for each sub-watershed. This research uses several variables: 1) soil type; 2) topography; 3) land use; and 4) climate (temperature, rainfall, solar radiation, wind speed, and relative humidity). Analysis conducted is Hydrology Response Units (HRUs) and statistical analysis. Variable physical characteristics are processed by the overlay method for HRUs analysis. Statistical analysis showed the values of R2 and NSE were 0.48 and 0.32. Based on the calibration and validation results, the values of R2 and NSE are 0.75 and 0.46. This shows a satisfactory and acceptable model. The runoff value tends to show a moderate category between 50-80 in the category of Coefficient of Flow Regime and this is precisely proportional to the rate of erosion. Each sub-watershed shows a high runoff value, tends to produce high erosion rate as well and its reverse. The rate of erosion indicates 175.0 tons/ha / year in the medium category.

The impact of the ENSO phenomenon causes a shift in the pattern of rainy and dry season. This will affect the agricultural activities Kebumen regency, crop failure and decreased productivity are few of the results of such impacts. This study aims to find the exposure pattern of dryland agriculture in Kebumen regency towards ENSO phenomenon and its association with maize productivity. The Data used is the daily rainfall period of 1986-2016 from 32 observer rain stations. There are five parameters to identify exposures are early deviation and duration of a dry season, rainfall of the maize, the maize harvest, the number of rainy days in maize harvest and the method used is scoring and overlay. The pattern of high exposure to dryland agriculture tends to be in mountainous areas. The El Nino Period of 2015 does not result in dryland agriculture Significantly being exposed due to low exposure, while the La Nina period results in moderate to high exposure cleaning Because land does not require too much water. In the El Nino period of 2015, maize productivity tends to rise 43% from normal conditions. In the La Nina period in 2010, the productivity of maize dropped by 63% Compared to normal conditions.

Water is very valuable resources that provide people and other living things. Besides the need for water for drinking, water resources play an important role in such as livestock, fisheries, water for irrigation and water recreation. However, water quality of the rivers may degrade due to the variation of land use as human activities increase. Cilutung watershed is dominated by the agricultural land use which in many studies shows that agricultural land use has a great impact on river deterioration. It does not affect only the physicochemical of water, the excessive amount of nutrient may harm the biotic ecosystem. The purpose of this study was assessing water quality of the rivers in Cilutung Watershed and the contributing factors using physicochemical and biological parameters. According to ANOVA and PPM calculations, water quality was affected by land use spatially and river discharge temporally. The overall results showed that the rivers were categorized as slightly polluted referring to WQI, BMWP, and Saprobic Index. In general, all water quality parameters measured in Cilutung watershed met water quality standard Class III as stipulated in Indonesia Government Regulation No. 82/2001. Therefore, water sources were still acceptable for fisheries, animal husbandry, and water for irrigation.

This study aims to investigate the effectiveness of water mist on suppressing a shielded fire. Full-scale experiments are carried out in a partition room of (lxwxh) 2x2x2.5 m size. Five water mist nozzle which consist of two type nozzle was used, high flow (fogjet) nozzle installed at top center of the room and fine spray nozzle installed at each side of room at high 1.5 m from ground. The pressure of water mist system was maintained at 20 bar which correspond to 2.6 lpm of water flow rate. Wood crib of 6.5 x 6.5 x 6 cm size was used as the fuel source. The obstruction used as a fuel shield has table like form with 40 x 40 cm cover area and 0.5 m height. The location of fuel source and fuel shield was varied (1) fuel source and shield at centre of room, (2) fuel source at one side of shield and the shield at centre of room, (3) fuel source and shield at corner of room, and (4)) fuel source at one side of shield and the shield at corner of room. Numerical simulation using FDS 6.5.3 was also performed to validate the use of FDS and get better understanding of the phenomena. The results showed that water mist was able to extinguish the fire around 20 s, 16 s, 30 s, and 24 s for scenario 1, 2, 3 and 4 respectively. It is also observe that the mist distribution around the shield and cover area of the shield play a role on the capacity and time needed of water mist to extinguish the fire.