The phrase "ensuing tsunami" refers to a massive and powerful ocean wave that happens as a result of a previous event or situation. It implies that there will be a big impact or consequence following an initial occurrence. Full definition
Many readers will be familiar with the tragedies caused by recent earthquakes in Christchurch, New Zealand (2010,2011), Haiti (2010), or the 2011 earthquake near Japan, whose ensuing tsunami caused the Fukushima nuclear plant to breakdown. (globalwarmingsolved.com)
Japan's National Police Agency said Friday that the death toll from the monster earthquake and ensuing tsunami had climbed to 6,911, with another 10,316 people missing. (religion.blogs.cnn.com)
There are grave concerns about the effect of the ensuing tsunami on less developed countries such as Indonesia, which was devastated by a similar event in 2004. (politics.co.uk)