<h2 class="ql-align-justify">Swell Waves</h2> Context: The Indian National Centre for Ocean Information Services (INCOIS) has issued a warning to the coastal states about the “complete suspension of operational and recreational activities. About:&nbsp;<ul><li class="ql-align-justify">Formed by an ocean swell, hence the name swell waves/swell surge.&nbsp;</li><li class="ql-align-justify">A swell wave is the formation of long wavelength waves on the surface of the sea.</li><li class="ql-align-justify">They propagate along the interface between water and air. Thus, they are often referred to as surface gravity waves.&nbsp;</li><li class="ql-align-justify">Origin:&nbsp;</li><li class="ql-indent-1 ql-align-justify">Do not occur due to the local winds, rather due to distant storms like hurricanes or even long periods of strong winds.&nbsp;</li><li class="ql-indent-1 ql-align-justify">Usually, states like Kerala witness swell waves as a result of strong winds in the southern part of the Indian Ocean, where an ocean swell is generated.</li><li class="ql-indent-1 ql-align-justify">Swell waves flooding events are called Kallakkadal in Kerala.</li><li class="ql-align-justify">Influencing Factors: wind speed, ocean surface area affected by wind blowing in the same direction (also known as fetch), and amount of time those winds blow over the same part of the ocean.</li><li class="ql-align-justify">Features of Swell Waves:</li><li class="ql-indent-1 ql-align-justify">Swells have a narrower range of frequencies and directions than locally generated wind waves.</li><li class="ql-indent-1 ql-align-justify">Swells take on a more defined shape and direction and are less random than locally generated wind waves.</li><li class="ql-indent-1 ql-align-justify">Swell waves often have a long wavelength but this varies with the size of the water body.&nbsp;</li><li class="ql-align-justify">Difference between Swell Waves and Tsunamis:</li><li class="ql-indent-1 ql-align-justify">Tsunami is a series of enormous waves created by an underwater disturbance usually associated with earthquakes occurring below or near the ocean.</li><li class="ql-indent-1 ql-align-justify">Tsunamis are around 10 times faster than swell waves. Although both swell waves and tsunamis slow down near the coast, the swell waves hit land at 30–50 km/h.</li></ul> <img src="https://lh7-us.googleusercontent.com/docsz/AD_4nXco7LmFxtKEYSmnZspIXw8TDI8KSppN90WV2lfh8jPlHEKYmLwj2gxHExia-RcyHXmJQjaPeD1_ufrCXYryq004jy3sQQ9RxY3WGu_R7P8zohieGIId-vta0adIKf4HlWu2h7h08cLRxsWuYlT2gIxmxKY?key=XlSsmjHyy5Son6H-8-nE3Q" height="325.38730684425906" width="462"> <img src="https://sunyaias-resources.s3.ap-south-1.amazonaws.com/content/ee1ad781-37cb-11ef-aa43-776be579c942.png">