V leto\u00c5\u00a1nji zimi je s pogostimi in obilnej\u00c5\u00a1imi\u00c2\u00a0sne\u00c5\u00benimi padavinami postalo\u00c2\u00a0aktualno vpra\u00c5\u00a1anje sne\u00c5\u00bene obte\u00c5\u00bebe. Sne\u00c5\u00bena odeja predstavlja obremenitev\u00c2\u00a0za razli\u00c4\u008dne objekte. 19. februarja je na Zaplani padlo 90 mm de\u00c5\u00beja na 40 cm debelo sne\u00c5\u00beno odejo, naslednji dan pa je padlo\u00c2\u00a0\u00c5\u00a1e 25 cm novega snega. Sne\u00c5\u00bena obte\u00c5\u00beba, ki je bila velika \u00c5\u00bee pred omenjenimi\u00c2\u00a0padavinami, se je \u00c5\u00a1e pove\u00c4\u008dala. Ocenjevanje sposobnosti sne\u00c5\u00bene odeje za\u00c2\u00a0zadr\u00c5\u00beevanje padavinske\u00c2\u00a0vode, kot ka\u00c5\u00beejo nekatere\u00c2\u00a0poglobljene raziskave, ni\u00c2\u00a0enostavno.<\/p>\n
Osnova za izra\u00c4\u008dun sne\u00c5\u00bene obte\u00c5\u00bebe je vodnatost snega, ki nam\u00c2\u00a0pove koli\u00c4\u008dino vode v dolo\u00c4\u008denem stolpcu sne\u00c5\u00bene odeje. Vodnatost snega se izra\u00c5\u00bea\u00c2\u00a0s koli\u00c4\u008dino vode, ki je padla na dolo\u00c4\u008deno povr\u00c5\u00a1ino\u00c2\u00a0(l\/m\u00c2\u00b2). Liter destilirane\u00c2\u00a0vode tehta 1 kg, kar pomeni, da zna\u00c5\u00a1a ob vodnatosti 50 l\/m\u00c2\u00b2 sne\u00c5\u00bena obte\u00c5\u00beba 50 kg\/m\u00c2\u00b2. Sposobnost sne\u00c5\u00bene odeje za\u00c2\u00a0zadr\u00c5\u00beevanje vode je odvisna od vi\u00c5\u00a1ine in strukture sne\u00c5\u00bene odeje. Debelej\u00c5\u00a1a sne\u00c5\u00bena odeja lahko zadr\u00c5\u00bei ve\u00c4\u008d vode, skozi plast\u00c2\u00a0ozrnjenega snega, zrnjenje poteka predvsem\u00c2\u00a0pri temperaturah blizu ledi\u00c5\u00a1\u00c4\u008da in preoblikuje oz. zaobli sne\u00c5\u00bene kristale, pa\u00c2\u00a0voda\u00c2\u00a0prakti\u00c4\u008dno neovirano odteka. Pri strukturi sne\u00c5\u00bene odeje so pomembne tudi morebitne plasti ledu, ki vsaj na uravnanem povr\u00c5\u00a1ju prepre\u00c4\u008dujejo odtok vode iz sne\u00c5\u00bene odeje v tla. Sklepamo lahko, da kombinacija\u00c2\u00a0debele sne\u00c5\u00bene odeje in de\u00c5\u00beja ne pomeni nujno ve\u00c4\u008dje vodnatosti snega in posledi\u00c4\u008dno ve\u00c4\u008dje\u00c2\u00a0sne\u00c5\u00bene obte\u00c5\u00bebe, saj padavinska voda pogosto\u00c2\u00a0odteka skozi sne\u00c5\u00beno odejo. Pri na\u00c4\u008drtovanju objektov,\u00c2\u00a0izpostavljenim sne\u00c5\u00beni obte\u00c5\u00bebi, je potrebno namenjati\u00c2\u00a0ve\u00c4\u008d pozornosti neoviranemu odtekanje vode, kar se zagotovi denimo\u00c2\u00a0z ustreznim\u00c2\u00a0naklonom strehe.<\/p>\n
Na uradni\u00c2\u00a0meteorolo\u00c5\u00a1ki postaji Grosuplje je zna\u00c5\u00a1ala sne\u00c5\u00bena obte\u00c5\u00beba 100 kg\/m\u00c2\u00b2. Na Zaplani je bila sne\u00c5\u00bena odeja debelej\u00c5\u00a1a, padlo je ve\u00c4\u008d padavin, zato lahko privzamemo, da je\u00c2\u00a0bila sne\u00c5\u00bena obte\u00c5\u00beba \u00c5\u00a1e nekoliko ve\u00c4\u008dja. Potrebno je poudariti, da podatki izhajajo iz meritev sne\u00c5\u00bene odeje na tleh. V leto\u00c5\u00a1nji zimi je namre\u00c4\u008d\u00c2\u00a0na dvignjenih predmetih ve\u00c4\u008d snega, kot na tleh, kjer se je sneg zlasti\u00c2\u00a0na za\u00c4\u008detku zime talil zaradi toplej\u00c5\u00a1ih tal. Na Zaplani je bila\u00c2\u00a0na za\u00c4\u008detku februarja 2010<\/a> razlika v vi\u00c5\u00a1ini snega med tlemi in dvignjenimi predmeti 25cm. Sne\u00c5\u00bena obte\u00c5\u00beba je bila\u00c2\u00a0na dvignjenih predmetih, kot so nadstre\u00c5\u00a1ki, torej ve\u00c4\u008dja kot na tleh. Voda\u00c2\u00a0z nadstre\u00c5\u00a1kov sicer\u00c2\u00a0obi\u00c4\u008dajno\u00c2\u00a0la\u00c5\u00beje odteka, vendar samo v primeru pravilne konstrukcije oz. ustreznega naklona strehe. \u00c4\u0152e upo\u00c5\u00a1tevamo spodnjo mejo sne\u00c5\u00bene obte\u00c5\u00bebe 100 kg\/m\u00c2\u00b2, je moral nadstre\u00c5\u00a1ek\u00c2\u00a0s povr\u00c5\u00a1ino 15 m\u00c2\u00b2 v leto\u00c5\u00a1nji zimi\u00c2\u00a0prena\u00c5\u00a1ati tono\u00c2\u00a0in pol te\u00c5\u00bee.<\/p>\n Viri podatkov:<\/p>\n – Slovenski meteorolo\u00c5\u00a1ki forum<\/p>\n – Matej Ogrin – “Sne\u00c5\u00bena odeja”, \u00c5\u00a1tudijsko gradivo za geografe<\/p>\n","protected":false},"excerpt":{"rendered":" V leto\u00c5\u00a1nji zimi je s pogostimi in obilnej\u00c5\u00a1imi\u00c2\u00a0sne\u00c5\u00benimi padavinami postalo\u00c2\u00a0aktualno vpra\u00c5\u00a1anje sne\u00c5\u00bene obte\u00c5\u00bebe. Sne\u00c5\u00bena odeja predstavlja obremenitev\u00c2\u00a0za razli\u00c4\u008dne objekte. 19. februarja je na Zaplani padlo 90 mm de\u00c5\u00beja na 40 cm debelo sne\u00c5\u00beno odejo, naslednji dan pa je padlo\u00c2\u00a0\u00c5\u00a1e 25 cm novega snega. Sne\u00c5\u00bena obte\u00c5\u00beba, ki je bila velika \u00c5\u00bee pred omenjenimi\u00c2\u00a0padavinami, se je \u00c5\u00a1e […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[11],"tags":[],"_links":{"self":[{"href":"http:\/\/www.slometeo.net\/zaplana\/blog\/index.php?rest_route=\/wp\/v2\/posts\/3467"}],"collection":[{"href":"http:\/\/www.slometeo.net\/zaplana\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.slometeo.net\/zaplana\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.slometeo.net\/zaplana\/blog\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.slometeo.net\/zaplana\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3467"}],"version-history":[{"count":32,"href":"http:\/\/www.slometeo.net\/zaplana\/blog\/index.php?rest_route=\/wp\/v2\/posts\/3467\/revisions"}],"predecessor-version":[{"id":3495,"href":"http:\/\/www.slometeo.net\/zaplana\/blog\/index.php?rest_route=\/wp\/v2\/posts\/3467\/revisions\/3495"}],"wp:attachment":[{"href":"http:\/\/www.slometeo.net\/zaplana\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3467"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.slometeo.net\/zaplana\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3467"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.slometeo.net\/zaplana\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3467"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}