{"id":2668,"date":"2021-07-29T13:41:32","date_gmt":"2021-07-29T11:41:32","guid":{"rendered":"https:\/\/copernicus.chmi.cz\/?p=2668"},"modified":"2021-11-15T09:45:47","modified_gmt":"2021-11-15T08:45:47","slug":"nasledky-tornada-na-jizni-morave","status":"publish","type":"post","link":"https:\/\/copernicus.chmi.cz\/index.php\/2021\/07\/29\/nasledky-tornada-na-jizni-morave\/","title":{"rendered":"N\u00e1sledky torn\u00e1da na ji\u017en\u00ed Morav\u011b"},"content":{"rendered":"<!-- wp:heading {\"level\":4}--><div class=\"gridContainer\">\n<h4><a href=\"https:\/\/www.facebook.com\/kagik.cuni\/?__cft__[0]=AZWGtaSfX_s7gDuU6oAqAyT_EQycRJrR6OhdCe8wAwCn6DfDMtY_bVV6hFAbVVemqD6KiHDolgp0D4ec4V-PLJvcEsCCt3FlU5KXgRc1qBe7v1IRJfXZr-UgnSv9M5boT8Tk18rU0RzoyGcFrOyxpFriUkgaF0k6yNAth8s5ZpzMezFsobC1D8_JDVU_GOWNgM1BCw6wKmiJW7gIIzNGbATebnV9Rs7etmYhI5fyLM411Q&amp;__tn__=-UC%2CP-y-R\"><strong>Katedra aplikovan\u00e9 geoinformatiky a kartografie, P\u0159F UK<\/strong><\/a>:<\/h4>\n<\/div><!-- \/wp:heading-->\n\n<!-- wp:paragraph--><div class=\"gridContainer\">\n<p>\u00a0Anal\u00fdzou dru\u017eicov\u00fdch sn\u00edmk\u016f je mo\u017en\u00e9 sledovat zm\u011bny, ke kter\u00fdm doch\u00e1z\u00ed na povrchu Zem\u011b. T\u00edmto zp\u016fsobem se nap\u0159\u00edklad sleduje zmen\u0161uj\u00edc\u00ed se rozloha ledovc\u016f, nebo de\u0161tn\u00fdch prales\u016f. K n\u00e1hl\u00fdm zm\u011bn\u00e1m m\u016f\u017ee doch\u00e1zet i b\u011bhem n\u011bkolika m\u00e1lo minut \u010di sekund a dost\u00e1vaj\u00ed p\u0159\u00edzvisko katastrofa. Jedna takov\u00e1 katastrofick\u00e1 ud\u00e1lost bohu\u017eel potkala 24. 6. 2021 i jih Moravy, kde se prohnalo torn\u00e1do \u00fazem\u00edm mezi Hodon\u00ednem a obc\u00ed Hru\u0161ky. Torn\u00e1do po sob\u011b zanechalo zna\u010dn\u00e9 materi\u00e1ln\u00ed \u0161kody a co h\u016f\u0159 i ob\u011bti na \u017eivotech. V map\u011b n\u00ed\u017ee je vid\u011bt vyhodnocen\u00ed zm\u011bn mezi dv\u011bma sn\u00edmky z 21. 6. 2021 a 29. 6. 2021 pomoc\u00ed zm\u011bnov\u00e9 anal\u00fdzy IR-MAD. Legenda mapy vyjad\u0159uje pravd\u011bpodobnost, s jakou do\u0161lo v obdob\u00ed mezi t\u011bmito sn\u00edmky ke zm\u011bn\u011b odrazivosti povrchu. Ze z\u00edskan\u00e9 vizualizovan\u00e9 informace tedy nen\u00ed mo\u017en\u00e9 p\u0159\u00edmo odhadnout k jak velk\u00e9 (finan\u010dn\u00ed) \u0161kod\u011b do\u0161lo, ale je mo\u017en\u00e9 vy\u010d\u00edst, jak\u00e1 konkr\u00e9tn\u00ed \u010d\u00e1st \u00fazem\u00ed byla zasa\u017eena, tedy p\u0159esnou dr\u00e1hu torn\u00e1da. Prvn\u00ed sn\u00edmek je po\u0159\u00edzen t\u0159i dny p\u0159ed katastrofou a druh\u00fd p\u011bt dn\u00ed po t\u00e9to ud\u00e1losti. Ned\u00e1 se tedy o\u010dek\u00e1vat, \u017ee v\u0161echny zm\u011bny, kter\u00e9 jsou mezi sn\u00edmky nalezeny, jsou zp\u016fsobeny pr\u00e1v\u011b torn\u00e1dem. Oba vybran\u00e9 sn\u00edmky byly lehce zasa\u017eeny obla\u010dnost\u00ed. Obla\u010dnost je v ka\u017ed\u00e9m sn\u00edmku na jin\u00fdch m\u00edstech a proto algoritmus vyhodnotil jako zm\u011bnu i m\u00edsta s oblaky. Z t\u011bchto d\u016fvod\u016f byla obla\u010dnost odmaskov\u00e1na (pomoc\u00ed produktu SCL), aby l\u00e9pe vynikly pouze zm\u011bny, kter\u00e9 byly zp\u016fsobeny torn\u00e1dem. Prob\u011bhnout t\u00e9\u017e mohla i \u0159ada zm\u011bn na pol\u00edch, kter\u00e9 nesouvisej\u00ed s katastrofickou ud\u00e1lost\u00ed. M\u016f\u017ee se jednat o sklize\u0148, dozr\u00e1v\u00e1n\u00ed, zaset\u00ed atd. Z toho d\u016fvodu bylo nutn\u00e9 parcely pol\u00ed, kde do\u0161lo k velk\u00fdm zm\u011bn\u00e1m a nach\u00e1zej\u00ed se d\u00e1le od trajektorie torn\u00e1da, odmaskovat, aby zm\u011bny zp\u016fsoben\u00e9 torn\u00e1dem ve v\u00fdsledn\u00e9m obraze l\u00e9pe vynikly. Anal\u00fdza IR-MAD tedy porovn\u00e1v\u00e1 dva dru\u017eicov\u00e9 sn\u00edmky (eventu\u00e1ln\u011b jak\u00e9koliv jin\u00e9 obr\u00e1zky) a pomoc\u00ed kanonick\u00e9 korelace z nich vytvo\u0159\u00ed nov\u00e9 dva obr\u00e1zky, kter\u00e9 by m\u011bly b\u00fdt sob\u011b navz\u00e1jem co nejv\u00edce podobn\u00e9. Po t\u00e9 jsou od sebe tyto nov\u00e9 dva obr\u00e1zky ode\u010dteny (metodou band by band, tj. pro ka\u017ed\u00e9 p\u00e1smo zvl\u00e1\u0161\u0165). M\u00edsta (pixely), u nich\u017e ke zm\u011bn\u011b nedo\u0161lo, by m\u011bla m\u00edt rozd\u00edly hodnot z obou porovn\u00e1van\u00fdch sn\u00edmk\u016f bl\u00edzk\u00e9 nule. Absolutn\u00ed suma t\u011bchto rozd\u00edl\u016f umocn\u011bn\u00fdch na druhou vyd\u011blen\u00fdch p\u016fvodn\u00ed hodnotou p\u0159edstavuje \u03c7\u00b2. \u010c\u00edm je tato suma vy\u0161\u0161\u00ed, t\u00edm je i vy\u0161\u0161\u00ed pravd\u011bpodobnost, \u017ee ke zm\u011bn\u011b do\u0161lo.<\/p>\n<\/div><!-- \/wp:paragraph-->\n\n<!-- wp:html--><div class=\"gridContainer\">\n<div id=\"fb-root\"><\/div>\n<script async=\"\" defer=\"\" crossorigin=\"anonymous\" src=\"https:\/\/connect.facebook.net\/cs_CZ\/sdk.js#xfbml=1&amp;version=v11.0\" nonce=\"26AJklZF\"><\/script>\n<div class=\"fb-post\" data-href=\"https:\/\/www.facebook.com\/CopernicusCR\/posts\/1820907604749000\" data-width=\"500\" data-show-text=\"true\"><blockquote cite=\"https:\/\/www.facebook.com\/CopernicusCR\/posts\/1820907604749000\" class=\"fb-xfbml-parse-ignore\">Zve\u0159ejnil(a) <a href=\"https:\/\/www.facebook.com\/CopernicusCR\/\">Copernicus v \u010cR<\/a> dne&nbsp;<a href=\"https:\/\/www.facebook.com\/CopernicusCR\/posts\/1820907604749000\">\u010ctvrtek 29. \u010dervence 2021<\/a><\/blockquote><\/div>\n<\/div><!-- \/wp:html-->","protected":false},"excerpt":{"rendered":"<p>Katedra aplikovan\u00e9 geoinformatiky a kartografie, P\u0159F UK: \u00a0Anal\u00fdzou dru\u017eicov\u00fdch sn\u00edmk\u016f je mo\u017en\u00e9 sledovat zm\u011bny, ke kter\u00fdm doch\u00e1z\u00ed na povrchu Zem\u011b. T\u00edmto zp\u016fsobem se nap\u0159\u00edklad sleduje zmen\u0161uj\u00edc\u00ed se rozloha ledovc\u016f, nebo&nbsp;&hellip;<\/p>\n","protected":false},"author":6,"featured_media":2669,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11],"tags":[],"class_list":["post-2668","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-novinky-2021"],"_links":{"self":[{"href":"https:\/\/copernicus.chmi.cz\/index.php\/wp-json\/wp\/v2\/posts\/2668","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/copernicus.chmi.cz\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/copernicus.chmi.cz\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/copernicus.chmi.cz\/index.php\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/copernicus.chmi.cz\/index.php\/wp-json\/wp\/v2\/comments?post=2668"}],"version-history":[{"count":2,"href":"https:\/\/copernicus.chmi.cz\/index.php\/wp-json\/wp\/v2\/posts\/2668\/revisions"}],"predecessor-version":[{"id":3157,"href":"https:\/\/copernicus.chmi.cz\/index.php\/wp-json\/wp\/v2\/posts\/2668\/revisions\/3157"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/copernicus.chmi.cz\/index.php\/wp-json\/wp\/v2\/media\/2669"}],"wp:attachment":[{"href":"https:\/\/copernicus.chmi.cz\/index.php\/wp-json\/wp\/v2\/media?parent=2668"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/copernicus.chmi.cz\/index.php\/wp-json\/wp\/v2\/categories?post=2668"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/copernicus.chmi.cz\/index.php\/wp-json\/wp\/v2\/tags?post=2668"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}