{"id":2615,"date":"2020-02-13T07:59:46","date_gmt":"2020-02-13T07:59:46","guid":{"rendered":"http:\/\/www.agust.net\/wordpress\/?p=2615"},"modified":"2022-12-07T17:26:50","modified_gmt":"2022-12-07T17:26:50","slug":"gunnlaugur-h-jonsson-edlisfraedingur-throun-hitastigs-i-eina-old","status":"publish","type":"post","link":"http:\/\/www.agust.net\/wordpress\/2020\/02\/13\/gunnlaugur-h-jonsson-edlisfraedingur-throun-hitastigs-i-eina-old\/","title":{"rendered":"Gunnlaugur H J\u00f3nsson e\u00f0lisfr\u00e6\u00f0ingur: \u00der\u00f3un hitastigs \u00ed eina \u00f6ld…"},"content":{"rendered":"
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Grein eftir Gunnlaug H J\u00f3nsson e\u00f0lisfr\u00e6\u00f0ing \u00ed fr\u00e9ttabla\u00f0inu 13. febr\u00faar 2020<\/p><\/div>\n

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\u00c1rsme\u00f0alhiti \u00ed eina \u00f6ld \u00e1 St\u00f3rh\u00f6f\u00f0a, Reykjav\u00edk og Stykkish\u00f3lmi,<\/p><\/div>\n

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\"\"Ve\u00f0urstofa \u00cdslands var stofnu\u00f0 1. jan\u00faar 1920<\/strong> og er \u00fev\u00ed 100 \u00e1ra \u00ed \u00e1r. Af \u00fev\u00ed tilefni er r\u00e9tt a\u00f0 l\u00edta yfir farinn veg og \u00fer\u00f3un ve\u00f0urfars \u00e1 \u00cdslandi \u00ed eina \u00f6ld. Oft er sagt a\u00f0 \u00fea\u00f0 \u00feurfi a\u00f0 kanna fort\u00ed\u00f0ina til \u00feess a\u00f0 gera s\u00e9r grein fyrir \u00fev\u00ed sem framt\u00ed\u00f0in kann a\u00f0 bera \u00ed skauti s\u00e9r. Hitastig er s\u00e1 \u00fe\u00e1ttur \u00ed ve\u00f0urfari sem mest er r\u00e6tt um \u00e1 \u00feessum t\u00edmam\u00f3tum. \u00deessi grein fjallar um \u00fer\u00f3un hitastigs \u00ed eina \u00f6ld \u00ed h\u00f6fu\u00f0sta\u00f0num Reykjav\u00edk auk Stykkish\u00f3lms og St\u00f3rh\u00f6f\u00f0a sem eiga s\u00e9r lengsta s\u00f6gu samfelldra hitam\u00e6linga \u00e1 \u00cdslandi. \u00de\u00e1 er huga\u00f0 a\u00f0 \u00fev\u00ed hva\u00f0 gerist ef \u00fer\u00f3unin ver\u00f0ur \u00f3breytt n\u00e6stu 100 \u00e1rin.<\/p>\n

Til \u00feess a\u00f0 setja breytingar \u00e1 hitastigi \u00ed samhengi<\/strong> eru h\u00e9r nokkrar sta\u00f0reyndir um breytingar \u00e1 hitastigi jar\u00f0arinnar \u00ed t\u00edma og r\u00fami. Mesti m\u00e6ldur hiti \u00e1 \u00cdslandi, 30,5\u00b0C, er talinn hafa m\u00e6lst fyrir 80 \u00e1rum 22. j\u00fan\u00ed 1939 \u00e1 Teigarhorni en s\u00e1 l\u00e6gsti m\u00e6ldist 21. jan\u00faar 1918 \u00e1 Gr\u00edmsst\u00f6\u00f0um og M\u00f6\u00f0rudal \u00e1 Fj\u00f6llum -38\u00b0C. Mismunurinn er 68,5\u00b0C. \u00c1 li\u00f0nu \u00e1ri m\u00e6ldist h\u00e6sti hiti \u00ed Reykjav\u00edk 21,1\u00b0C en s\u00e1 l\u00e6gsti -12,1\u00b0C. Mismunurinn er 33,2\u00b0C. Mesti hiti sem hefur m\u00e6lst \u00e1 landi \u00ed heiminum er 56,7\u00b0C m\u00e6ldur 10. j\u00fal\u00ed 1913 \u00ed Furnace Creek \u00ed Californ\u00edu en s\u00e1 l\u00e6gsti \u221289.2\u00b0C \u00feann 21. j\u00fal\u00ed 1983 \u00e1 Su\u00f0urskautslandinu. Mismunurinn er 145,9\u00b0C. \u00deeim mun v\u00ed\u00f0ar sem vi\u00f0 f\u00f6rum \u00ed t\u00edma og r\u00fami \u00feeim mun meiri l\u00edkur eru \u00e1 \u00fev\u00ed a\u00f0 finna hitastig sem v\u00edkur langt fr\u00e1 me\u00f0alhita jar\u00f0arinnar sem er n\u00fa talinn vera um 15\u00b0C. \u00c1ri\u00f0 1960 fyrir 60 \u00e1rum, samkv\u00e6mt bestu vitneskju \u00feess t\u00edma, var me\u00f0alhiti jar\u00f0arinnar l\u00edka talinn vera 15\u00b0C.<\/p>\n

Me\u00f0fylgjandi tafla<\/strong> gefur t\u00f6lulegar uppl\u00fdsingar um \u00e1rsme\u00f0alhita \u00ed 100 \u00e1r \u00ed Reykjav\u00edk, Stykkish\u00f3lmi og \u00e1 St\u00f3rh\u00f6f\u00f0a. T\u00f6lurnar eru fengnar me\u00f0 \u00farvinnslu \u00e1 uppl\u00fdsingum af vef Ve\u00f0urstofunnar. Eins og vi\u00f0 er a\u00f0 b\u00faast er hl\u00fdjast \u00e1 St\u00f3rh\u00f6f\u00f0a
\nsem er sy\u00f0st en kaldast \u00ed Stykkish\u00f3lmi sem er nyrst og munar 1,2\u00b0C. Sta\u00f0alfr\u00e1vik \u00ed me\u00f0alhita eru 0,70\u00b0C \u00ed Stykkish\u00f3lmi, 0,66\u00b0C \u00ed Reykjav\u00edk en a\u00f0eins 0,56\u00b0C \u00e1 St\u00f3rh\u00f6f\u00f0a, sem er umlukinn hafi.<\/p>\n

Me\u00f0fylgjandi mynd<\/strong> s\u00fdnir \u00fer\u00f3un hitastigs \u00e1 ofangreindum \u00ferem st\u00f6\u00f0um s\u00ed\u00f0ustu 100 \u00e1rin. \u00c1 myndinni m\u00e1 sj\u00e1 mikla hl\u00fdnum fyrstu 14 \u00e1rin fr\u00e1 1919 til 1933. Eftir \u00fea\u00f0 st\u00f3\u00f0 hitinn nokkurn veginn \u00ed sta\u00f0 til \u00e1rsins 1960. \u00c1 \u00feessu hl\u00fdja t\u00edmabili f\u00f3r \u00e1rsme\u00f0alhitinn \u00e1 St\u00f3rh\u00f6f\u00f0a fimm sinnum yfir sex gr\u00e1\u00f0ur. Eftir 1960 hefur hann a\u00f0eins \u00ferisvar fari\u00f0 yfir sex gr\u00e1\u00f0ur \u00e1 St\u00f3rh\u00f6f\u00f0a og einu sinni \u00ed 6,1\u00b0C \u00ed Reykjav\u00edk \u00e1ri\u00f0 2003 en \u00fea\u00f0 var hl\u00fdjasta \u00e1ri\u00f0 \u00e1 100 \u00e1rum. Me\u00f0alhiti st\u00f6\u00f0vanna \u00feriggja var 5,9\u00b0C \u00fea\u00f0 \u00e1r. N\u00e6st hl\u00fdjasta \u00e1ri\u00f0 var \u00e1ri\u00f0 1941 \u00feegar hitinn var a\u00f0 me\u00f0altali 5,8\u00b0C. \u00dea\u00f0 li\u00f0u \u00fev\u00ed 62 \u00e1r \u00fea\u00f0 til me\u00f0alhitinn fr\u00e1 1941 var sleginn um 0,1\u00b0C.<\/p>\n

Eftir 1960 k\u00f3lna\u00f0i<\/strong> og \u00ferj\u00e1t\u00edu \u00e1ra t\u00edmabili\u00f0 1931 til 1960 var a\u00f0 jafna\u00f0i 0,6\u00b0C hl\u00fdrra en t\u00edmabili\u00f0 1961 til 1990. \u00c1 \u00feessu kuldat\u00edmabili gengu j\u00f6klar \u00e1 \u00cdslandi fram og \u00e1 \u00e1ttunda \u00e1ratugnum voru mestu h\u00e6tturnar sem ste\u00f0ju\u00f0u a\u00f0 mannkyninu taldar vera kjarnorku\u00f3gnin og n\u00e6sta \u00eds\u00f6ld. Eftir aldam\u00f3ta\u00e1ri\u00f0 2000 hefur hl\u00fdna\u00f0 aftur. Ve\u00f0urstofan hefur til skamms t\u00edma nota\u00f0 \u00feetta kalda t\u00edmabil til samanbur\u00f0ar vi\u00f0 l\u00ed\u00f0andi \u00e1r.<\/p>\n

N\u00fa telja margir a\u00f0 mesta \u00f3gnin <\/strong>sem ste\u00f0jar a\u00f0 j\u00f6r\u00f0inni og mannkyni s\u00e9 hl\u00fdnun jar\u00f0ar.<\/strong> \u00cd t\u00f6flunni eru s\u00fdndar hallat\u00f6lur fyrir bestu l\u00ednur sem falla a\u00f0 hitaferlum s\u00ed\u00f0ustu 100 \u00e1ra. Hallat\u00f6lurnar s\u00fdna \u00e1rlega hl\u00fdnun sem nemur \u00fe\u00fasundustu hlutum \u00far gr\u00e1\u00f0u \u00e1 \u00e1ri. \u00c1 einni \u00f6ld nemur hl\u00fdnunin 0,25\u00b0C \u00e1 St\u00f3rh\u00f6f\u00f0a, 0,36\u00b0C \u00ed Reykjav\u00edk og 0,57\u00b0C \u00ed Stykkish\u00f3lmi. Hl\u00fdnun \u00e1 einni \u00f6ld er \u00fev\u00ed minni en sem nemur sveiflu \u00ed me\u00f0al\u00e1rshita (sta\u00f0a\u00f0alfr\u00e1vik) \u00feessara st\u00f6\u00f0va. Haldi \u00feessi \u00fer\u00f3un \u00ed ve\u00f0urfari \u00e1fram \u00f3breytt n\u00e6stu 100 \u00e1rin til 2120 m\u00e1 v\u00e6nta \u00feess a\u00f0 me\u00f0alhiti \u00ed Reykjav\u00edk fari \u00far 4,8\u00b0C og ver\u00f0i 5,4\u00b0\u00b10,7\u00b0C \u00e1ri\u00f0 2120. Mannvirki og malbik \u00ed st\u00f3rborginni London valda \u00fev\u00ed a\u00f0 hiti er \u00fear 2-3\u00b0C h\u00e6rri en \u00ed sveitunum \u00ed kring. Uppbygging h\u00f6fu\u00f0borgarsv\u00e6\u00f0isins og aukin trj\u00e1r\u00e6kt mun l\u00edklega h\u00e6kka v\u00e6ntan hita \u00ed Reykjav\u00edk \u00ed framt\u00ed\u00f0inni um allt a\u00f0 eina gr\u00e1\u00f0u til vi\u00f0b\u00f3tar. St\u00f3rh\u00f6f\u00f0i er ekki l\u00edklegur til \u00feess a\u00f0 byggjast \u00ed framt\u00ed\u00f0inni og er \u00fev\u00ed einstakur sta\u00f0ur \u00e1 \u00cdslandi til \u00feess a\u00f0 m\u00e6la langt\u00edmabreytingar \u00e1 hitastigi enda me\u00f0 m\u00e6lingar fr\u00e1 1869. \u00de\u00e6r m\u00e6lingar s\u00fdna a\u00f0 hl\u00fdnunin var mun hra\u00f0ari \u00e1 t\u00edmabilinu 1869-1919 (0,71\u00b0C \u00e1 \u00f6ld) en \u00e1 li\u00f0num hundra\u00f0 \u00e1rum eftir a\u00f0 koltv\u00eds\u00fdringur \u00ed andr\u00famsloftinu f\u00f3r a\u00f0 aukast verulega.<\/p>\n

P.S. Vil kvarta yfir \u00fev\u00ed vi\u00f0 Ve\u00f0urstofuna<\/strong> a\u00f0 me\u00f0al\u00e1rshitat\u00f6lur fyrir t\u00edmabili\u00f0 1931-1948, sem var hl\u00fdtt t\u00edmabil, eru ekki a\u00f0gengilegar eins og \u00e1\u00f0ur. Taflan sem \u00e1\u00f0ur h\u00f3fst \u00e1ri\u00f0 1931 hefst n\u00fa \u00e1ri\u00f0 1949 ?? sem var \u00f3venju kalt \u00e1r, \u00fea\u00f0 kaldasta \u00e1 t\u00edmabilinu 1922 til 1966! Hva\u00f0a r\u00f6k eru fyrir \u00feessari breytingu?<\/p>\n

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Gunnlaugur H. J\u00f3nsson er e\u00f0lisfr\u00e6\u00f0ingur.<\/p>\n

(Leturbreytingar: \u00e1hb – www.agust.net )<\/span><\/p>\n

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    Ve\u00f0urstofa \u00cdslands var stofnu\u00f0 1. jan\u00faar 1920 og er \u00fev\u00ed 100 \u00e1ra \u00ed \u00e1r. Af \u00fev\u00ed tilefni er r\u00e9tt a\u00f0 l\u00edta yfir farinn veg og \u00fer\u00f3un ve\u00f0urfars \u00e1 \u00cdslandi \u00ed eina \u00f6ld. Oft er sagt a\u00f0 \u00fea\u00f0 \u00feurfi a\u00f0 kanna fort\u00ed\u00f0ina til \u00feess a\u00f0 gera s\u00e9r grein fyrir \u00fev\u00ed sem framt\u00ed\u00f0in kann a\u00f0…<\/p>\n","protected":false},"author":2,"featured_media":2616,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[8,1],"tags":[],"_links":{"self":[{"href":"http:\/\/www.agust.net\/wordpress\/wp-json\/wp\/v2\/posts\/2615"}],"collection":[{"href":"http:\/\/www.agust.net\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.agust.net\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.agust.net\/wordpress\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"http:\/\/www.agust.net\/wordpress\/wp-json\/wp\/v2\/comments?post=2615"}],"version-history":[{"count":13,"href":"http:\/\/www.agust.net\/wordpress\/wp-json\/wp\/v2\/posts\/2615\/revisions"}],"predecessor-version":[{"id":3795,"href":"http:\/\/www.agust.net\/wordpress\/wp-json\/wp\/v2\/posts\/2615\/revisions\/3795"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/www.agust.net\/wordpress\/wp-json\/wp\/v2\/media\/2616"}],"wp:attachment":[{"href":"http:\/\/www.agust.net\/wordpress\/wp-json\/wp\/v2\/media?parent=2615"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.agust.net\/wordpress\/wp-json\/wp\/v2\/categories?post=2615"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.agust.net\/wordpress\/wp-json\/wp\/v2\/tags?post=2615"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}