Preprints
Search for indonesia (66 results)
Application of Probabilistic Machine Learning to the prediction of Remotely Sensed Vegetation Health
Published: 2021-05-28
Subjects: Environmental Studies
Every prediction of the future carries some level of uncertainty; making this explicit is challenging. This paper introduces a Probabilistic Machine Learning algorithm, namely the Natural Gradient Boosting algorithm, as a modelling tool for predicting the Vegetation Health Index, a proxy for monitoring vegetation stress in response to changing weather conditions. It then elaborates on the time [...]
A numerical study of SMART Cables potential in marine hazard early warning for the Sumatra and Java regions
Published: 2021-05-04
Subjects: Earth Sciences, Geophysics and Seismology, Other Earth Sciences
We present results from a series of exploratory numerical experiments based on ocean bottom pressure and seismic data from a simulated linear array of SMART cable stations off the trench in the Sumatra-Java region. We use six rupture scenarios to calculate tsunami propagation using hydrodynamic simulations. Through these experiments we show that such an addition would result in up to several [...]
Plastic pollution research in Indonesia: state of science and future research directions to reduce impacts
Published: 2021-04-09
Subjects: Environmental Sciences
Several studies have suggested Indonesia to be among the top plastic polluting countries globally. Data on the presence and amounts of plastic pollution are required to help design effective plastic reduction and mitigation strategies. Research quantifying plastic pollution in Indonesia has picked up in recent years. However, a lack of central coordination in this research has led to research [...]
Long-term hydrometeorological time-series analysis over the central highlands of West Papua
Published: 2021-04-06
Subjects: Physical Sciences and Mathematics
This article introduces an innovative data-driven approach to examining the long-term temporal rainfall patterns in the central highlands of West Papua, Indonesia. Through the utilization of wavelet transforms, we identified signs of a negative temporal correlation between the El Niño-Southern Oscillation (ENSO) and the 12-month Standardized Precipitation Index (SPI-12). Building upon this [...]
New insight into post-seismic landslide evolution processes in the tropics
Published: 2021-03-05
Subjects: Earth Sciences, Geomorphology, Geophysics and Seismology, Hydrology
Earthquakes do not only trigger landslides in co-seismic phases but also elevate post-seismic landslide susceptibility either by causing a strength reduction in hillslope materials or by producing co-seismic landslide deposits, which are prone to further remobilization under the external forces generated by subsequent rainfall events. However, we still have limited observations regarding the [...]
Hydro-Meteorological Aspects of the 2021 South Kalimantan Flood: Topography, Tides, and Precipitation
Published: 2021-03-01
Subjects: Earth Sciences, Hydrology, Meteorology
The 2021 South Kalimantan flood was recorded as the most serious ever to have taken place in the province. It occurred due to high-intensity rain during the period 10-19 January, accompanied by a spring tide. This study provides an overview of the disaster, with reference to the hydro-meteorological conditions (topography, tides, and precipitation). The method used was the analysis of the [...]
Structural and stratigraphic development of Offshore NW Sulawesi, Indonesia
Published: 2021-02-14
Subjects: Earth Sciences, Geology, Geomorphology, Sedimentology, Stratigraphy, Tectonics and Structure
The area of the Offshore NW Sulawesi lies between eastern Sundaland (Borneo) and the North Arm of Sulawesi. Possible influences on the basins include Paleogene rifting in the Celebes Sea and Makassar Strait, Neogene subsidence and uplift in Borneo, late Neogene subduction at the present-day North Sulawesi Trench, and displacements related to the Palu-Koro Fault. This study presents the results of [...]
Back to the fields: COVID-19 impact on agricultural activity detected with satellite data
Published: 2021-02-03
Subjects: Environmental Studies
In response to the 2020 COVID-19 pandemic, policymakers worldwide adopted unprecedented measures to limit disease spread, with major repercussions on labour markets and economic growth. Here we provide empirical evidence of their impact on agricultural activity due to sectoral labour reallocation. Analysing daily satellite data in a non-parametric machine learning statistical framework over [...]
Regional disparities and seasonal differences in climate risk to rice labour
Published: 2021-01-21
Subjects: Environmental Health and Protection, Environmental Indicators and Impact Assessment
The 880 million agricultural workers of the world are especially vulnerable to increasing heat stress due to climate change, affecting the health of individuals and reducing labour productivity. In this study, we focus on rice harvests across Asia and estimate the future impact on labour productivity by considering changes in climate at the time of the annual harvest. During these specific times [...]
Bias correction of global climate model using machine learning algorithms to determine meteorological variables in different tropical climates of Indonesia
Published: 2020-12-11
Subjects: Applied Statistics, Atmospheric Sciences, Planetary Geophysics and Seismology, Statistical Models
Accurate and localized forecasting of climate variables are important especially in the face of uncertainty imposed by climate change. However, the data used for prediction are either incomplete at the local level or inaccurate because the simulation models do not explicitly consider local contexts and extreme events. This paper, therefore, attempts to bridge this gap by applying tree-based [...]
Double-difference earthquake relocation using waveform cross-correlation in Central and East Java, Indonesia (Preprint)
Published: 2020-11-25
Subjects: Earth Sciences, Geophysics and Seismology
The Central and East Java region, which is part of the Sunda Arc, has relatively high seismic rates due to the convergence of two major tectonic plates in the Indonesian region; i.e., the Indo-Australian Plate subducting under the Eurasian Plate. Many devastating earthquakes have occurred in this area as a result of the interaction between these two plates. Two examples are the 1994 Banyuwangi [...]
Iron oxide reactivity controls organic matter mineralization in ferruginous sediments
Published: 2020-07-10
Subjects: Biogeochemistry, Earth Sciences, Life Sciences, Physical Sciences and Mathematics
Ferruginous sediments were widespread during the Archaean and Proterozoic Eons, but our knowledge about organic matter mineralization remains mostly conceptual, as analogous modern ferruginous sediments are largely unstudied. In sediments of ferruginous Lake Towuti, Indonesia, methanogenesis dominates organic matter mineralization despite abundant reactive ferric iron phases persisting throughout [...]
Seismic swarm preceding the 2017 Mount Agung eruption in Bali (Indonesia) enhanced by the matched filter approach
Published: 2020-07-02
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Intense swarm seismicity took place before the 2017 Mount Agung eruption in Bali (Indonesia). However, the earthquake sequences were not well documented. In addition, there was a substantial delay between the peak of the seismic activity (late September) and the onset of the impending eruption (late November). We applied waveform-based hypocenter relocation and matched filter technique (MFT) to [...]
Excessive seismicity over a limited source: the August 2019 earthquake swarm near Mt. Salak in West Java (Indonesia)
Published: 2020-06-22
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
The triggering mechanism of swarm-like seismicity in the Java Island of Indonesia is generally not well understood. Understanding earthquake swarm phenomena and monitoring in various tectonic settings can be improved by the detection of micro-earthquakes; however, such a catalog is not available due to various reasons including the existing limited seismic network and using an outdated algorithm [...]
Lateral variability in strain along a mass-transport deposit (MTD) toewall: a case study from the Makassar Strait, offshore Indonesia
Published: 2020-04-18
Subjects: Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics, Sedimentology
Contractional features characterise the toe domain of mass-transport deposits (MTDs). Their frontal geometry is typically classified as frontally-confined or frontally-emergent. However, it remains unclear how frontal emplacement style and contractional strain within an MTD can vary along strike. We use bathymetry and 3D seismic reflection data to investigate lateral variability of frontal [...]