THE POSSIBILITY OF TIDAL FLOOD ON PROBOLINGGO COASTAL AREA AND ITS COMPARISON CONDITION BETWEEN WEST AND EAST SEASONS BASED ON OCEANOGRAPHICAL AND METEOROLOGICAL DATA

Tidal flood has become a serious problem in several coastal areas in Indonesia, particularly in Probolinggo, East Java Province - Indonesia. The study of tidal flood in the coastal area of Probolinggo was conducted by processing and analyzing oceanographical and meteorological data to asses the possibility and to compare its variability between the West and East seasons. Data is used for this study consist of tidal and wind data from Stamet II Perak Surabaya (7 years from 2004 - 2011); rainfall data from BMKG Juanda Surabaya (9 years from 2002 - 2011); and Probolinggo topography data from SRTM (Shuttle Radar Topography Mission - http://srtm.csi.cgiar.org/). Tidal flood occurrence possibility was determined by comparing the sea level heights with the topography of the study area. the meteorological data were analyzed to compare its variability during West and East seasons. Results show that tidal flood may occur at several points on the coast of Probolinggo while the high tide occurs especially during the spring tide since the sea level was higher (0.73 m) than the topography of the coastal area of Probolinggo (<0.5 m by average). The condition becomes worse during the East season due to the existence of strong wind in the direction that contributes to generating a high wave in the coastal.Rob atau banjir pasang air laut telah menjadi permasalahan serius di beberapa daerah pesisir di Indonesia, khususnya Probolinggo. Kajian mengenai banjir rob di wilayah ini telah dilakukan dengan mengolah dan menganalisa data-data oseanografi dan meteorologi untuk mengkaji seberapa besar potensi kejadian dan perbandingan kondisinya saat musim Barat dan Timur. Data-data yang digunakan adalah data pasang-surut (pasut) dan angin wilayah Probolinggo selama 7 tahun (2004 - 2011) dari Stamet II Perak Surabaya, serta data topografi Probolinggo dari Shuttle Radar Topography Mission (SRTM). Potensi terjadinya banjir rob ditentukan dengan membandingkan tinggi muka air ini dengan topografi daerah kajian. Data meteorologi dianalisa untuk dibandingkan kondisinya saat musim Barat dan Timur. Hasil menunjukkan bahwa banjir rob dapat terjadi di beberapa titik di pesisir Probolinggo saat pasang tinggi khususnya selama periode pasang purnama akibat tinggi muka air yang lebih tinggi (0,73 m) daripada ketinggian topografi daerah kajian (rerata <0.5 m). Kondisi akan lebih buruk selama musim Timur akibat datangnya angin kencang dari arah yang berpotensi dalam kemunculan gelombang tinggi di pesisir. &nbsp