A one year comparison of radar and pressure tide gauge at Goa, west coast of India

At many locations absolute pressure gauges are used to obtain sea level data. Therefore, knowledge of the other physical processes which effect the sea level measurements at the coast is very important to insert the required corrections. Data from the radar and an absolute pressure gauge are obtained over a period of one year from the test site at Verem, Goa, India. The variance of difference between the radar and absolute pressure gauge is 15.9 cm 2 , which reduces to 5.7 and 4.0 cm 2 respectively, when atmospheric pressure and water density variations are introduced for obtaining sea level from an absolute pressure gauge. The regression analysis indicates that atmospheric pressure, water density and rainfall can account for the difference individually up to 71%, 33% and 27% respectively. The aim of the present study is to quantify the effects of atmospheric and oceanographic variables while measuring sea level using pressure gauges and to highlight the advantages of the radar gauge over other type of gauges with regard to easy installation, maintenance and could be given precedence in future applications.