{"id":2293,"date":"2024-03-10T15:26:55","date_gmt":"2024-03-10T22:26:55","guid":{"rendered":"http:\/\/tradewindssailing.com\/wordpress\/?p=2293"},"modified":"2024-12-09T19:04:11","modified_gmt":"2024-12-10T03:04:11","slug":"nautical-terminator-king-tides","status":"publish","type":"post","link":"https:\/\/www.tradewindssailing.com\/wordpress\/nautical-terminator\/nautical-terminator-king-tides\/","title":{"rendered":"Nautical Terminator – King Tides"},"content":{"rendered":"\n

In this world of few certainties, there is one thing that I am certain of: I am not certain how the tides work. Oh, it\u2019s the moon\u2019s gravity, and I think the sun is involved. Well, then, how is it that on a new moon, when the sun and the moon are both on the same side of the earth, we still have two tides? Shouldn\u2019t there be just one big one? <\/p>\n\n\n\n

\"\"<\/a><\/figure>\n\n\n\n

            I was\nreminded of these puzzles recently because of what the news media were calling\n\u201cKing Tides.\u201d This isn\u2019t official terminology from NOAA; it\u2019s used to sensationalize\nthe highest tides of the year. The media routinely explained that these tides\noccur \u201cwhen the sun, moon, and earth are in alignment.\u201d But wait just a durned\nminute. Doesn\u2019t that happen twice in every single month, in which case they are\njust plain old \u201cspring\u201d tides? How do these get the royal treatment if they\u2019re\nno different from the commoners?<\/p>\n\n\n\n

            King\nTides occur near perihelion<\/em>, when the\nearth is closest\u2014not by all that much\u2014to the sun. Perihelion occurred on\nJanuary 4. If it got real close, you\u2019d think we\u2019d feel pretty warm. But no, it\nhappens in winter. The highest tide this season was 7.18 feet on December 13,\n2012 on a new moon. <\/p>\n\n\n\n

\"\"<\/a><\/figure>\n\n\n\n

             However, six months later, we again have very\nhigh tides, when the earth is at aphelion,<\/em>\nits farthest from the sun, and paradoxically, it is hot. On July 21, on\na full moon, the predicted tide is 7.07 feet, barely lower than the December\ntide. So our distance from the sun isn\u2019t the only factor. Since this is a\nyearly cycle, it is the result of the sun\u2019s influence, not the moon\u2019s monthly\npattern. It turns out the latitude<\/em> of\nthe sun is as important as its distance, and at our summer solstice the sun\u2019s over\nthe northern hemisphere. This makes up for the greater distance and generates\nour big summer tides. In Australia, where, as best I can figure, The \u201cKing\u201d\ntides got their name, summer solstice occurs during perihelion, meaning latitude\nand distance are both at their peak influence. So if you want to experience the\nwhole shebang, you\u2019ll have to go down under.<\/p>\n\n\n\n

            But\nit\u2019s nowhere near this simple. Again, of this I\u2019m certain. We used three tidal constituents\nfor this analysis. NOAA uses 37, but the total number is 396.<\/p>\n","protected":false},"excerpt":{"rendered":"

In this world of few certainties, there is one thing that I am certain of: I am not certain how the tides work. Oh, it\u2019s the moon\u2019s gravity, and I think the sun is involved. Well, then, how is it … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":13,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[31],"tags":[],"class_list":["post-2293","post","type-post","status-publish","format-standard","hentry","category-nautical-terminator"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_likes_enabled":true,"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.tradewindssailing.com\/wordpress\/wp-json\/wp\/v2\/posts\/2293","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.tradewindssailing.com\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.tradewindssailing.com\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.tradewindssailing.com\/wordpress\/wp-json\/wp\/v2\/users\/13"}],"replies":[{"embeddable":true,"href":"https:\/\/www.tradewindssailing.com\/wordpress\/wp-json\/wp\/v2\/comments?post=2293"}],"version-history":[{"count":3,"href":"https:\/\/www.tradewindssailing.com\/wordpress\/wp-json\/wp\/v2\/posts\/2293\/revisions"}],"predecessor-version":[{"id":3489,"href":"https:\/\/www.tradewindssailing.com\/wordpress\/wp-json\/wp\/v2\/posts\/2293\/revisions\/3489"}],"wp:attachment":[{"href":"https:\/\/www.tradewindssailing.com\/wordpress\/wp-json\/wp\/v2\/media?parent=2293"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.tradewindssailing.com\/wordpress\/wp-json\/wp\/v2\/categories?post=2293"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.tradewindssailing.com\/wordpress\/wp-json\/wp\/v2\/tags?post=2293"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}