Ocean Networks Canada<\/a>.<\/p>\n\u201cThe warm equatorial water rises on top of any cold water. As this warm water \u2018sloshes\u2019 into the continent, some of it hits land and turns north, while some turns south. That water that turns north moves up the coastline as what\u2019s called a Kelvin wave,\u201d said Watson.<\/p>\n
Watson said that there is some discussion on whether this slosh of warm water is still a Kelvin wave by the time it reaches Vancouver Island; so, for clarity, he calls it the \u201cENSO impact.\u201d<\/p>\n
Watson also says that while this impact is often referred to as a Kelvin wave, it does not behave like a traditional wave, such as those that surfers ride. Nor is it a wall of water, like a tsunami. The ENSO impact doesn\u2019t create higher tides (that\u2019s due to the moon and solar gravity); it layers on top of high tides, sometimes adding up to 30 cm of water.<\/p>\n
\u201cJust like warm air rising because it\u2019s less dense than cold air, warm water also sits on top of cold water because it\u2019s less dense. That warm water also expands relative to colder water. When that water expands, it leads to higher sea levels,\u201d he said. \u201cThe impact of El Ni\u00f1o \u2014 whether we call it a Kelvin wave or something else \u2014 will bring warmer waters and higher sea levels via a mass of slow-moving water or several masses of slow-moving water over the course of several months.\u201d<\/p>\n
However, the ENSO impact will manifest differently on Vancouver Island\u2019s east coast compared to its shores on the open ocean. Watson says that while Tofino and Nanaimo are at about the same latitude, their tides differ in terms of time of day and magnitude because of geography, weather, ocean bottom features, and Fraser River discharge, just to name a few features.<\/p>\n
So, when one thinks about the characteristically big waves on the west coast of the island, the ENSO impact could lead to higher water levels on their shores. However, areas like the Comox Valley don\u2019t typically get the \u201cTofino-style\u201d waves.<\/p>\n
For the Comox Valley, the ENSO impact will mean warmer temperatures in Baynes Sound, which may cause increased bacteria outbreaks in shellfish. Watson says that changing water temperatures could also lead to shifts in the composition and distribution of ocean species.<\/p>\n
\u201cAnother way that ENSO more broadly \u2014 beyond the \u2018Kelvin wave\u2019 strictly \u2014 affects the region is through altered weather patterns,\u201d said Watson. \u201cA southward shift in winter storm systems often leaves BC with milder and drier winters, leading to lower snowpacks, which can lead to changes in lake and river systems where salmon eggs and juveniles are incubating or rearing, respectively.\u201d<\/p>\n
Watson says any risks associated with the ENSO impact depend on where people live on the island and says coastal residents should stay tuned to local advisories and emergency management authorities. In areas where people harvest shellfish, they should be extra vigilant about shellfish harvest advisories.<\/p>\n
\u201cIndustry is always watching water quality, so they are likely already paying extra attention and doubling down on their monitoring,\u201d said Watson.<\/p>\n
ENSO impacts are likely to affect water levels the most in early winter; however, warmer water temperatures on the east coast could persist longer than that. Predicting the exact timing and duration of these effects is challenging due to other factors, said Watson.<\/p>\n","protected":false},"excerpt":{"rendered":"What\u2019s in a wave? How a Kelvin wave could impact Vancouver Island\u2019s east coast Published 1:42 pm Tuesday,…\n","protected":false},"author":2,"featured_media":948711,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[194298],"tags":[49,48,55],"class_list":["post-948710","post","type-post","status-publish","format-standard","has-post-thumbnail","category-vancouver","tag-ca","tag-canada","tag-vancouver"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/948710","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/comments?post=948710"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/948710\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media\/948711"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media?parent=948710"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/categories?post=948710"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/tags?post=948710"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}