Rjeas Research Journal in Engineering and Applied Sciences 2(2) Rjeas

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1 Rjeas Research Journal in Engineering and Applied Sciences 2(2) Rjeas Emerging Academy Resources (2013) (ISSN: ) THE IMPACT OF SEA LEVEL RISE TO PUBLIC HEALTH: SPATIAL ASSESSMENT APPROACH FOR JAKARTA Dewayany Sutrisno 1 and Rizka Windiastuti 2 1 Indonesian Society for Remote Sensing, Jln. M.H Thamrin No 8, Jakarta 77777, Indonesia 2 Geospatial Information Agency, Jln. Raya Jakarta Bogor km 46, Cibinong 16911, Indonesia Corresponding Author: Dewayany Sutrisno ABSTRACT Sea level rise affects the existence of natural resources as well as the welfare of human being. Shoreline retreat and inundation are some impacts that may due to this phenomenon. Poverty and poor sanitation will worsen this impact. Therefore, spatial model seems has to be established beforehand, as an input for decision makers for planning and developing better management for nature, environment and the society. Using Northern Jakarta municipality as the study area, this study is aimed to develop a spatial model to estimate the impact of sea level rise related to the public health. The model was developed based on the modification of Sutrisno s shoreline retreat model. The result of the study indicates that the people living in the slump area are more defenseless to the infectious diseases cause by inundation and its related factors. So, the study assume that improving the sanitation, infrastructure facilities and develop more green environment are the best plan to decrease the vulnerability of the society in facing such catastrophe. In this case, this study is clearly seen the significance of the model to assist the development of the healthy environment to increase the human welfare. A science input that should be read and aware by the community since sea level rise phenomenon is just around the corner of the coastal cities.. Emerging Academy Resources KEYWORDS: Sea level rise, health, inundation, shoreline retreat, Jakarta INTRODUCTION The phenomenon of global warming has significant impact on global livelihood. Sea level rise is one of it. a scientific evidence for the local government to implement a better policy for improving social wellbeing of Jakartans. Sea level rise may cause coastal inundation that indirectly may affect the public health on the risky area, especially if it is occurred within the populous The aim of the study is to develop a model to project the impact of sea level rise to the coastal city and its cities such as Jakarta. Moreover, whereas there is the social problems by engaged North Jakarta lack of well manage public infrastructure and sanitation, the impact will be more severely menacing. The new species introduction, such as the water related infectious species, to the coastal municipality as the study case in. In order to give input for better management of this municipality in facing the sea level rise phenomenon, environment problems and its related social welfare inhabitants as the impact of climate change may decrease the value of life on the people livelihood as the sea level rise increase. Indeed, the development based on economic approach and the increased of poverty caused by urbanization may decrease the quality of environment of the risky area to this nature METHOD Basically, the research flow of spatial model development can be seen in the figure 1 which illustrated the steps from data inventory to the model development and assessment. phenomenon. North Jakarta municipality is a good example for this nature and human induce factors phenomenon. Since Jakarta has been encountered by annual flooding, land subsidence due to massive ground water discharge caused by rapid population and infrastructure development and also rising slump area and poverty caused by massive urbanization. To mitigate this impact, nature and society, a spatial model is definitely needed to project the future impact of sea level rise on coastal area and its residents. Implementing the model to the regularly environmental problems such as flooding hopefully will project the risk zone area to the human health as Figure 1. The Research flow of the model 152

2 The steps of the research can be explained as follow; Data Inventory Prior to the t data collecting, parameters of the model should be determined. These parameters should be consisted of the parameters of shoreline retreat as mandatory to the Sutrisno s model (2005), the annual flooding data and the social and human health statistical data. In this study, the human health data was only considered the water related diseases case, such as dengue and diarrhea. The data may be collected primary, such as slump area data or secondary, such as human health data, social statistic data, tidal data and annual flooding data. The reference base map data should also be prepared prior to the data digitalizing processes. Data Processing The data processing may consist of: A. Tidal data processing. Taken from nearby tidal gauge stations, i.e Tanjung Priok tidal gauge station ( ), the data was being processed to obtain the trend of sea level rise. B. Flooding data processing. This process aim to obtain flooding risk zone. Whereas the area can be classified as high risk zone, and moderately risk zone and low risk zone C. Social data processing. This process will map the distribution of water related diseases such as diarrhea and dengue. The classification of the data may consist of risk, moderately risk and low risk, analyzed using the scoring method that can be described in the following criteria: Risk Classes (R d ) = f (ratio of incindet (t), incindent (t), fatal (t) ) (1) The scoring values are 100 for high risk, 80 for moderately risk and 50 for low risk. Modelling The data from processing were being input for the modeling process that can be explained as follow: A. Sea Level Rise Projection Model Using tidal data that has been processed prior to the model, the projection of sea level rise was assessed based on Ding et al (2002) formula, there is: k 0 at c sin 2 t / p q (2) t k k k 1 Whereas Z 0 is the average of sea level at t months observation, a is the trend of sea level rise, t is time (months), while c k, p k and q k is the period, amplitudes and tidal phase at year of k B. Sea Level Rise (SLR) Impact Projection Model Using the data from sea level projection and other related parameters data, the spatial impact of sea level rise on coastal area, i.e inundation, was developed using Sutrisno s shoreline retreat model (2005) and can be explained as follow: Z S L. h D Z 1 R (3) Whereas: R = Shoreline retreat (m) Z = Sea level rise (m) S = Sediment accumulation change, obtain from secondary data observation (m) L = length delta front (m), the area of sedimentation processes h = Depth at L (m) D = elevation (m) The model development can be further explained in Figure 2 Figure 2. The diagram of shoreline retreat model C. Inundation Risk Projection Model The method that was used for this modeling is scoring method with the notion that the whole slump area can be categorized as the risky area. The risky zone classes can be classified as Risk and high risk whereas, Inundation risk area (R g )= f(risk to flooding, risk to sea level rise, slump) (4) The scoring can be determined as 100 for high risk, 80 for moderately risk and 50 for low risk, 100 for risk to Sea level rise, 100 for slump area and 10 for not slump area D. Health Risk Projection Model The notions for the modeling consist of the area that saddening the risk of inundation as a result of sea level rise and flooding, risk to health and categorized as slump area. Therefore, it can be determined as; Risk to illness (RP) = f( inundation risk (t), slump, prone to illness) (5) The scoring method is also used in this spatial projection model and the risk information can be classified as high risk, medium risk dan low risk. The scoring is 100 for high risk inundation, 80 for moderately inundation risk,100 for slump area, 10 for 153

3 not slump area, 100 for high prone illness, 80 for moderately prone to illness and 50 for less prone to illness. Prone to illness is assessed from the range of of incident rate of infectious diseases RESULT AND DISCUSSION Sea Level Rise Projection And Its Impact On Coastal Area The north Jakarta coastal area is believed to be the most risky area in coping with the sea level rise phenomenon. The tidal data analysis from Tanjung Priok tidal gauge station that was being assessed using least square linier regression to bivariate distribution value for 27 years tidal data observation (a) ( ) indicate the trend of sea level rise on about 0.71 cm/year. The illustration of this trend can be seen in Figure 3(a) for monthly tidal data trend and 3(b) for annual tidal data trend. However, inundation cause by the sea level rise is not the only problems that pressurized the North Jakarta coast. Land subsidence as the result of ground water discharge is another factor that Jakarta should face in the near future. The social activity that lead this phenomenon generate relative sea level rise as major type of sea level rise occurred in Jakarta, as it can be seen in figure 3. (b) Figure 3. The graph of the trend of sea level rise ( ), monthly (a) and annually(b) The projection of sea level rise indicates the escalating trend. Herewith, it can be projected that at 2050 there will be 48.3 cm sea level rise at the business at usual (BAU). This projection supposed to be within the projection of the previous research as can be illustrated in Figure 4 (Sutrisno, 2005) and (Susandi, 2008) Figure 4. The projection of sea level rise up to 2050, (a) research result, (b) Susandi (2008) and Sutrisno (2005) Furthermore, the projection of coastal inundation can be described in Figure 5, as the result of shoreline retreat model implementation. The three sea level rise scenarios become the input for this inundation projection assessment. Meanwhile, the spatial projection of this model can be seen in figure 6 which indicate without any mitigation processes, the north Jakarta coast will be severely inundated within the next 60 years. This will become more advance occur to the higher topography area due to the land subsidence phenomenon 154

4 Figure 5. Projection of three scenarios inundation to 2080, Jakarta coast Figure 6. Simulation of the inundation of North Jakarta Coast as a result of sea level rise up to 2080 The Projection of Flooding and Inundation Regardless the impact of sea level rise, Jakarta due to its morphological factor has been pressurized by annual flooding. The topography of north Jakarta coast that lower than the sea level and the 13 rivers across Jakarta territory make Jakarta become severely menace by flooding and inundation. Moreover, the intensive urban development decrease the green area availability for water infiltration will increase the flooding risk area as well. The sea level rise phenomenon aggravate the coastal inundation as can be seen in Figure 6 (b), whereas despite the sea level rise, the annual flooding has been occurred as can be illustrated in Figure 6 (a). The simulation for 2080 indicates the intensifying projection of inundation risk area in north Jakarta coast that possibly will be advanced to the higher topography area due land subsidence phenomenon. The Projection of the Impact of Sea Level Rise to the Social Health In accordance with the rapid economic development, the social problem seems to be rapidly increased in north Jakarta area. The economic role in north Jakarta is basically due to the trade, services and business area to support Jakarta as the service city that inversely do not decrease the numbers of the needy and the slump area but become the core of urbanization and increasing of the slump area. The existing well build residential area, port of Tanjung Priok, tourism and resorts, industrial and warehouse business area are the main spatial land use of North Jakarta that make the social economic activity of North Jakarta is basically business. However, the development of the slump area in contrast to the economic purposes development (see Figure 7) can be found among at many sub districts at those business area, suchas at Penjaringan, Penjagalan, Ancol, Pademangan, Sunter Agung, Sunter Jaya, Papango, Tanjung Priok, Warakas, Kebun Bawang, Sungai Bambu, Koja, Rawa Badak Selatan dan Utara, Lagoa, Semper, Cilincing, Rorotan sub district. 155

5 (a) (b) Figure 6. Flooding risk area zone (a) and projection of the advance inundation caused by sea level rise (b) The slump housing is varied from permanent house to the temporary tents with the poor infrastructure and sanitation. At the rainy season, these areas are annually humid, cold and inundated. Indeed, the majority of the people are living under the poverty line. With the assumption that the slump area usually has poor infrastructure facilities, the spatial risk of flooding or inundation can be further analyzed. The spatial model of inundation or flooding within the slump area is illustrated in Figure 8 (a). Meanwhile, the spatial distribution of slump area can be figured at Figure 7 Furthermore, the projection of sea level rise at business as usual (BAU) indicates the phenomenon of inundation is not only occurred within the slump area but also to the elite residential area and well build business area (Figure 8(b)). Still the needy has highest risk as it is illustrated in Figure 8(b). Figure 8a. The flooding risk zone Figure 7. The Location of slump area in North Jakarta Figure 8b. Simulation of the sea level rise risk projection (b) 156

6 The Sea Level Rise Projection and its Impact on Social Health Considering the infectious water related diseases such as dengue and diarrhea, the assessment of these diseases indicate the risk area as illustrated in Figure 9a-b. It can be seen that almost north Jakarta are the risk zone, including the slump, the elite residential and business area. The highest risk zone are Pluit, Pejagalan, Kapuk muara, Ancol, Koja, Kalibaru, Cilincing, Marunda, Tugu Utara and Kelapa Gading sub district for dengue and Kamal Muara, Ancol, Tj.Priok, Lagoa, Sukapura, and Kelapa Gading Barat for diarrhea. The incindet rate Figure 7. The Location of slump area in North Jakarta ratio per population numbers and its trend that tend to increase within the last three years become the basic criteria for this public health risk assessment. Besides that, relating to the poor access to healthy environment and facilities, the people that living in the slump area can be considered as the high risk for these two infectious diseases. The spatial risk health at the slump area can be described in Figure 10a-b, which include Koja sub district for diarrhea and Pejagalan, Koja, Rawa Badak Selatan, Cilincing, Kalibaru, Tugu utara and Marunda for dengue. (a) (b) Figure 9. Dengue risk zone (a) and diarrhea risk zone (b) Figure 10. dengue risk zone (a) and diarrhea risk zone (b) The assessment uses the slump area as the high risk area to the two water related infectious diseases indicate the relation of the inundation and the diseases (Figure 10 a- b). Indeed, the projection of the advance inundation caused by the sea level rise phenomenon indicate the increasing risk area for these infectious diseases (Figure 11a-b) 157

7 Figure 11. Simulation of Dengue risk area projection (a) and diarrhea (b) due to the sea level rise phenomenon. As it is stated before, at the business as usual, the threat of the diseases is not only occurred at the slump area but also within the elite zone as can be seen in Figure 12 a-b Figure 12. Simulation of dengue risk area projection (a) and diarrhea (b) as the sea level rise occurred within the elite and business area risky due to the poor sanitation, poor facilities and less of access to the health facilities. CONCLUSION AND SUGGESTION Jakarta is one of the coastal city that has highest risk to sea level rise phenomenon, whereas the majority is caused by relative sea level rise. The increasing number of population and social economic activity and their need to the ground water may cause the land subsidence and ending to this relative Sea level rise as much as 0.71 cm/year. Without any mitigation, it is projected that 70 years later, the north Jakarta that has already pressured by annual flooding will be more drowning to 201 meters landward caused by sea level rise Considering water related diseases, the projection of inundation indicate that almost of north Jakarta area become the risk zone for dengue and diarrhea, eventhough the slump area is considers as the most Even though the projection illustrated the relation of the sea level rise, inundation to the water related diseases, it can t be said that the inundation caused by this phenomenon has direct relation with these two diseases seeds development. Considering Aedis aigepty, a species of mosquito that cause dengue, the life growth of this type of dangerous mosquito is much more depend on the temperature and clean water environment. The fact that climate change has spread the dengue epidemic upward to the highland may indicate the relation of this mosquito to the temperature parameters eventhough the inundation still has the impact on the life growth of this species. 158

8 Therefore, the further study of the relationship of mosquito life growth to the climate change is definitely needed. So, by developing the model of these two parameters will help to project and mitigate the epidemic of the disease. Moreover, regardless the weaknesses of the assumption derived for the model, the development of this model that relating the phenomenon of sea level rise to the human health will become the early warning system for the government and the society to improve the mitigation efforts both for inundation purposes and sanitation or healthy environment that the community need know from this study. REFERENCES Ding, X.L., D.W. Zheng, Y.Q. Chen and C. Huang Sea Level Change In Hongkong From Tide Gauge Records. Journal Of Geospatial Engineering 4:1, The Hongkong Institute of Engineering and Surveyors, pages Sutrisno D., The Impact of Sea Level Rise on delta Management: The Study Case of Shrinp Ponds in Muara Ulu Island Mahakam Delta. IPB Bogor 2005 Susandi, Ami The Affect of Sea Level Rise and high wave to Jakarta Flooding parameters. Environment Management agency Jakarta Province. Jakarta 159