ORIGINAL PAPER Mapping of seawater inundation along Nagapattinam based on field observations M. V. Ramana Murthy • N. T. Reddy • Y. Pari • Tune Usha • P. Mishra Received: 16 September 2009 / Accepted: 21 May 2011 Ó Springer Science+Business Media B.V. 2011 Abstract Nagapattinam, in the east coast of India, was severely affected during the deadliest Indian Ocean tsunami of December 26, 2004. The tsunami caused heavy damage to life and property, and the death toll was about 3,378 in Nagapattinam taluk. Certain villages along the coast witnessed large inundation while adjacent villages were protected from the fury of the tsunami waves. This study was carried out to examine the underlying causes for the vulnerability along Nagapattinam coast with the help of field observations, remote sensing, and geographical information system as tools. Coastal areas with high sand dunes have been protected from tsunami, and areas adjacent to backwaters were inundated. Realtime Kinematic Global Positioning System and high-resolution satellite data were used to map the topographic information and maximum extent of inundation. Thematic maps on land use, land cover, and coastal geomorphology were generated using remote sensing and field data. Using field data as the primary source of information, tsunami hazard maps have been generated for Nagapattinam. Keywords East coast of India Á Nagapattinam Á Tsunami Á Inundation Á Run-up Á Geomorphology Á Hazard Map 1 Introduction Nagapattinam district (Fig. 1) in India’s eastern coast was one of the worst affected regions in mainland India due to the tsunami that hit the Indian coast with a magnitude of 9.3 M w on December 26, 2004. The Nagapattinam district has five taluks (subdivisions of a dis- trict) and supports a population of about 1,48,70,55. All the five coastal taluks of Na- gapattinam district namely Nagapattinam, Keelvelur, Vedaranyam, Tarangambadi, and Sirkali were severely affected by the tsunami. The district has a large coastline of 140 km, and inland gradients indicate that most of the coastal areas have low coastal slope M. V. Ramana Murthy Á N. T. Reddy (&) Á Y. Pari Á T. Usha Á P. Mishra ICMAM-Project Directorate, Ministry of Earth Sciences, NIOT Campus, Velachery-Tambaram Main Road, Pallikaranai, Chennai, Tamil Nadu 600100, India e-mail: tirupati2020@gmail.com 123 Nat Hazards DOI 10.1007/s11069-011-9950-1