Western Monsoon Research Articles

Radon levels in Bengaluru during monsoon season.

A study on the dynamics of Radon and meteorological parameters was conducted in Bengaluru (12056'44'' N, 77030'25″ E, 840m AMSL) during monsoon of 2014. All measured parameters exhibited a clear diurnal pattern, except for pressure, and are attributed to morning temperature inversion and afternoon enhanced vertical mixing. Concentration of Radon is higher during north eastern monsoon compared with south western monsoon and is due to the presence of continental air mass from north east of India. Monthly average Radon activity has exhibited a positive link with long wave radiation while displaying a negative correlation with ambient temperature, accumulated rainfall and soil temperature. During the study, ambient gamma dose rate of 190.8 nSv hour-1, shortwave radiation of 184.4 Wm-2, longwave radiation of -40.4 Wm-2, soil temperature (at 10cm) of 26.3°C, humidity of 62.9%, pressure of 918.1mbar and radon activity of 8.4±0.5Bq m-3 were recorded.

Income of labor fishermen households and the adaptation strategy that was contained in fulfiled the prominent needs in West Monsoon (Case Study in Village of West Sekotong, West Lombok Regency West Nusa Tenggara Province)

Labor fishermen are the structure of the fishing community that has the poorest socioeconomic level. Labor fishermen do not have fisheries assets and only rely on Labor to get income from sharing the results with owner fishermen. During the western monsoon (famine) Labor fishermen’s fishing activities are very limited, so it needs adaptation strategies to fulfill their daily basic needs. The aims of this study are: to analyze the level of income of Labor fishermen households in the west monsoon and to find out the adaptation strategies conducted by Labor fishermen households in fulfilling their basic needs in the west monsoon. This research uses descriptive methods and data collection techniques using survey techniques. Respondents were selected from 60 random sampling of Labor fishermen households. The results showed: a) The household income of Labor fishermen in the western monsoon was IDR 1,442,667 and b) adaptation strategies conducted by fishermen households in fulfilling their basic needs in the western monsoon are fishermen Labor working off fishing, utilizing family members to earn a living, doing social gathering, withdrawing savings, borrowing from neighbors, borrowing from the skipper (boat owner), borrowing from cooperatives, and selling the household asset.

Pengaruh Suhu Permukaan Laut terhadap Curah Hujan di Pulau Bali Tahun 2009-2018

Change in sea surface temperature (SST) has a huge impact to rainfall intensity. This research analysed the trend of SST all over Bali island for 10 years (from 2009 to 2018) using MODIS satellite level 3, covered 7.8958oSouth -8.8958oSouth and 114.4791oEast - 115.6875oEast. The data for rainfall trend was collected from 12 rain observer stations of BMKG (Indonesian Meteorological, Climatological, and Geophhysical Agency). The statistical correlation between SST and rainfall intensity were analyzed using Microsoft Excel software. The result found that the SST in Bali ranged from 25.4oC until 31.5oC. The change of SST has a similar pattern to the monsoon cycle where the western monsoon is relatively warmer than the eastern monsoon. The rainfall trend in Bali is closely related to the monsoon cycle. During the western monsoon,the average monthly rainfall value in Bali is more than 150 mm, while the rainfall value on the eastern monsoon is slightly different, which is <150 mm. The correlation between SST and rainfall is influenced by the monsoon direction.The correlation between SST and rainfall in the west and transitional season Iis weak with a coefficient correlation value of -0,46 at lag 0, whereas in the east and transitional season II showed a strong correlation coefficient value of 0.94 in lag 0 (in the same month).

Water Quality Modeling Distribution at Bali Strait in the Western Monsoon and Its Impact for Ecosystems

The Bali Strait is geographically located between Java and Bali Island, with a total area approximately 900 square miles. It has a high potential of fish produces an average of 100 tons/year. The types of fishes there are tongkol, layang, and lemuru with high economic values. Bali Strait affected by the oceanographic phenomenon of upwelling in the Indian Ocean and has shallow and narrow bathymetry conditions made high currents speeds. The abundance of nutrients in Bali Straits made the ocean water fertile and rich in fish give an advantage for anglers. The nutrient is present in Bali Strait caused by water flow from land. These conditions is become triggers for an explosion of phytoplankton populations or called booming algae. The shrimp waste from companies disposing of the waste to Bali Strait consists of parameter DO, BOD, COD, TSS, Phosphate, and Nitrate. Research on the distribution of water quality in Bali Strait in the Western Monsoon has to research, where previous researchers have researched in the Eastern Monsoon. The purpose of this research is to find out the distribution of water quality parameters in the Bali Strait using MIKE 21 Ecolab [1]. The result of this research shown the maximum distribution exceed water quality parameter and influence for the biota are BOD = 83.031 mg/L, Nitrate = 0.924 mg/L, Phosphate = 0.176 mg/L and TSS = 27.574 mg/L. The BOD makes the water polluted, Nitrate and Phosphate is the trigger for booming algae, and TSS is not suitable for coral and sea grass.

Study of Debris Movement in South and West Coast of Sumatra and Java and Its Impact on Bali Strait During Western Monsoon

Bali Strait is one of the most unique and important water areas, especially for the coastal communities of Banyuwangi and Jembrana up to Badung Regency. The Bali Strait has Sardinella lemuru fish resources where it is widely exploited and is the main livelihood income of the coastal communities. In recent years, the quality of Sardinella lemuru fish has begun to decline due to contamination of microscopic plastic debris in the Bali Strait during western monsoon. Many previous researches have carried out the movement of debris in the Bali Strait using numerical model to find out the source and location of the marine debris, however it only carried out local simulations within the Bali Strait. This study aims to determine the movement of debris that reaches the Bali Strait assuming debris originates from coastal areas on south and west coast of Sumatra and Java during the western monsoon (December 2018 - February 2019). The Finite Volume Coastal Ocean Model (FVCOM) model is used to obtain circulation of current patterns and debris particles movement patterns using the Lagrangian Particle Tracking module. The verification result of the model current pattern and field data using the Root Mean Square Error (RMSE) equation. In the u velocity component the RMSE value is 0.014 m/s with a correlation of 0.968 and the v velocity component is 0.011 m/s with a correlation of 0.945. In general, the current pattern in the waters of southern of Sumatra Island to Java Island in the dominant western monsoon moves eastward due to the influence of western monsoon. The simulation results show particles that reached the Bali Strait as much as 3.47% originating only from the coastal waters of East Java.

Estimating Trends of Mean Monthly Ozone Emission in Urbanised Areas of Malaysia

AbstractA 21 year (1992 – 2012) daily ozone emission data of a highly urbanised district in Malaysia was analysed with the aim of estimating the trend of ozone emission and relating this trend to the socio – economic and climatic characteristics of the area. Daily ozone emission dataset used in this study were obtained from the World Ozone and Ultraviolet Data Centre (WOUDC). The data were aggregated to obtain the mean monthly emission data. Descriptive and inferential statistical analyses were conducted to describe the datasets. Trend of the ozone emission was estimated with the use of MANN - KENDALL test. The magnitude of the trend was derived by the use of ordinary least-square fitting and the significance of trend was also tested with the use of MANN-KENDALL tool. The results of the statistical analysis indicated that the highest ozone emission occurred during the south western monsoon (May to August) period and these mean monthly ozone emission differed significantly over the study period. The trend analysis indicated a yearly decrease of between 0.069 ppt to 9.45 ppt for all the months except for the month of June when the predicted ozone concentration increased between 0.403 ppt and 0.414 ppt over 2020 to 2100. Furthermore, the results indicated that the ozone emission datasets yielded good estimates (predictive power of over 90%) with polynomial regression model. It could be concluded that the results of this study provided useful evidence for the importance of the climatic factors such as ambient air temperature, relative humidity on ozone formation. More so, this study could be useful in developing baseline information for assessing the health impact of ozone emission and for urban airshed modelling.

Characteristics of Tidal in Surabaya

Ocean tides are the result of gravitational and centrifugal effect. Tidal motion in certain places does not only depend on the gravity moon and sun, but also by non-astronomical factors. The purpose of this study is to analyze the characteristics of the tides in Surabaya. The Methodology of this research are data collection, calculation using admiralthy methods, harmonic analysis, and trend analysis. The results showed that the waters of Surabaya has a type of tidal mixed semi diurnal. Results of the analysis of the tides in the Port of Perak shows there has been a rise in the function y = 0.0164 (x) + 156.86 every month from January 1994 - December 2009 or 1.97 mm per year. The lowest Mean Sea Level (MSL) occurred in January 1998, which is 141 cm. MSL in Surabaya unstable to Western Monsoon ends. The highest MSL occurs in transition between Eastern Monsoon towards the Western Monsoon, April 2008 amounted to 179 cm.

Floristic Composition Of The Remaining Forests In Upland Cavite, Luzon Island, Philippines

Cavite Province lies in the western monsoon forest zone of the Philippines and is considered as a tropical lowland rainforest making it a haven for diverse flora and fauna. The existing total land forest area is 8,624.956 hectares, but the only proclaimed national park is Mts. Palay-palay/Mataas na Gulod Protected Landscape. Unfortunately, the remaining forests are not spared from biodiversity loss because of its accessibility to Metro Manila, which eventually leads to unsustainable use of natural resources. This study was conducted to characterize the floristic composition, analyze the vegetation structure, and provide an inventory of plants in the provinces’ remaining forests. Data collection was done from June 2014 to March 2016. Forty- six plots (20m x 20m) were used for tree species composition. The plot size for shrub and non-woody plants was 5m x 5m quadrats while for herbaceous plants it was 1m x 1m quadrat. Plant diversity and environmental parameters in each plot were measured and recorded. Canonical Correspondence Analysis (CCA) was employed to analyze the relationships between vegetation and environmental variables. The study documented 501 species belonging to 336 genera and 113 families. Three vegetation types, secondary forest, agricultural ecosystem, and semisecondary (mixed forest) were documented in the remaining forests in Upland Cavite and the Protected Area (PA) part is characterized as lowland evergreen dipterocarp rainforest dominated by Shorea guiso, Ficus chrysolepis, Diospyros pyrrhocarpa, Buchanania arborescens and Strombosia philippinensis. The forest floor is dominated by Anaxagorea luzonensis, Aglaonema commutatum and Bolbitis rhizophylla.

The incidence of low phosphorus soils in Australia

Low phosphorus (P) soils have been described as a widespread characteristic of the Australian continent and associated with sclerophyll leaf traits. In that context we ask: what proportion of the continent is low-P and how much does this vary between regions? 9234 locations sampled for soil total P from the Australian National Site Soil Data Collation were analysed. In order to make some adjustment for uneven spatial sampling we area-weighted the data using subregions from the Interim Bioregionalisation of Australia. Topsoil total P concentrations ≤100 mg kg−1 were widespread, but not a majority of the continent (estimated 25 %). The western Monsoon Tropics (65 %), southwestern Australia (50 %), and southeast South Australia (38 %) were estimated to have larger fractions of the sampled landscape ≤100 mg kg−1 than eastern Australia (13.5 %), but not a lower range of values. Total P values across the continent included a large fraction (33 %) in the range 101–250 mg kg−1. Continent-wide soil P levels low enough to favour long leaf lifespans for nutrient conservation and a variety of sclerophyll traits were widespread. It is time to move away from the qualitative dichotomies between low- and high-P that have characterised discussion of Australian vegetation, to a more quantitative view.

Enhancing a Distributed Rainfall Intensity for Flood Analysis within a GIS Framework in an Urban Area (Kajang Flood)

The town of Kajang has experienced major flood events in previous decades since 1970s. Due to Eastern and Western Monsoon seasons in Malaysia, Kajang has potential to face with number of flood events. One of the critical elements in flood analysis is rainfall distribution. Therefore, flood studies need to have an optimum cognition of rainfall distribution as main input. In this study, HEC GeoHMS model was used in GIS (Geographic Information System) for Sungai Jeluh catchment (Kajang) due to estimation (visualization) of distributed rainfall in Kajang. In comparison with conventional methods, which they produced rainfall in lumped mode (e.g. Thiessen’s polygon), HEC GeoHMS visualized and tabulate a full distribution of rainfall for each small part (pixel of map) in a case study. HEC GeoHMS model for Sungai Jeluh has been set up by feeding high resolution of spatial and temporal resolution data (precipitation). Result of this study shows that rainfall by high intensity is distributed near urban area (downtown) in comparison with upstream which involved with less rainfall intensity.