Sonke sibonile imephu yolungelelwaniso apho kukho iimeridians eziphawulweyo. Baninzi abantu abangazi kakuhle yintoni meridians. Iimeridians kunye nongqamaniso yimigca emibini yentelekelelo apho ilizwe lihlala lilungelelaniswe ngokwejografi. Ngabo, kumiselwa inkqubo yolungelelwaniso evumela indawo echanekileyo yayo nayiphi na indawo emhlabeni ngokusekelwe kwisibanzi kunye nobude bayo.
Kweli nqaku sikuxelela ukuba yintoni i-meridians, zeziphi iimpawu zabo kunye nokubaluleka kwazo.
yintoni meridians
Ngokukodwa, i-meridian ngumgca othe nkqo esinokuwahlula umhlaba ube ngamacandelo alinganayo. Zonke ziqala kwi-North Pole kwaye zisasazeke eMzantsi (kunye nakwelinye icala). Imigca enxuseneyo, kwelinye icala, zimigca ethe tye efanayo. Umgca ohambelanayo ongu-0 yiikhweyitha. Phinda okufanayo ngokuzoba izangqa ezincinci kumantla nakumazantsi ehemispheres. Indibaniselwano yezi seti zimbini zemigca zenza igridi.
Zombini ezi ndidi zemigca zinendawo yesalathiso apho imigca yobude kunye nobubanzi inobalwa kuyo, kusetyenziswa i-sexagesimal (ichazwa ngolu hlobo lulandelayo: izidanga, imizuzu, nesekondi):
- Iimeridians. Zilinganiswa ngomlinganiselo weengile nganye (1°), kuqalwa kwinto ebizwa ngokuba yi-0° meridian okanye iGreenwich meridian, kanye indawo enqumla eLondon apho iRoyal Greenwich Observatory yayikhe yaba khona. Ukusuka apho, i-meridians inokuthathwa njengempuma okanye entshonalanga, kuxhomekeke kwindlela yokuqhelana nayo ngokubhekiselele kuloo mgca, kwaye umhlaba wahlulwe ube ngamacandelo angama-360 okanye "gajos".
- Ukufana. Zilinganiswa ukusuka kwi-ikhweyitha, kuthathelwa ingqalelo ii-engile ezizenzayo ngokubhekiselele kwi-axis yoMhlaba yokujikeleza: 15 °, 30 °, 45 °, 60 ° kunye ne-75 °, zonke ezikumntla we-hemisphere (umz., 30 °N) , njengasemazantsi (30° S).
Izicelo
Isiphumo sosetyenziso lwale nkqubo siba:
- Inkqubo yendawo yexesha, igqitywe nguMeridian. Okwangoku, ifomathi ye-GMT (iGreenwich Mean Time, “Greenwich Mean Time”) isetyenziselwa ukumela ixesha nakweyiphi na indawo yehlabathi, ukongeza okanye ukuphungula iiyure ngokwe-meridian elawula ilizwe ngalinye. Umzekelo, izowuni yexesha laseArgentina yi-GMT-3, ngelixa indawo yexesha lasePakistan iyi-GMT+5.
- Inkqubo yemozulu yomhlaba, igqitywe ngemigca ehambelanayo. Kokuthiwa zingqamana ezintlanu ezihlukeneyo, zi (ukusuka emantla ukuya emzantsi): iArctic Circle (66° 32' 30» N), iTropic of Cancer (23° 27' N), i-Equator (0°), iTropic of Cancer. (23 ° 27' S) kunye ne-Antarctic Circle (66° 33' S), uMhlaba wohlulwe ngokwemozulu okanye imimandla yenzululwazi ngeenkwenkwezi, ezi: iindawo ezishushu, iindawo ezinobushushu obuphantsi kunye neendawo ezimbini zomkhenkce okanye ezimhlophe. Nganye ineemeko zemozulu ezifanayo ngenxa yendawo yayo yelatitudinal.
- Inkqubo yokulungelelanisa yehlabathi. Oku kuvumela ukusetyenziswa kwezixhobo ze-geolocation ezifana ne-GPS (i-Global Positioning System, "Global Positioning System").
Njengoko sibonile kwimeko yangaphambili, igridi ivela kwindibaniselwano ye-meridians (i-longitudes) kunye ne-latitudes (i-latitudes). Inkqubo yolungelelwaniso lwejografi ibandakanya ukumelwa kwexabiso lendawo ukusuka kwirekhodi yamanani yobubanzi kunye nobude kwi-sexagesimal.
Umzekelo, i-geographical coordinates yaseMoscow yi-55° 45' 8" N (oko kukuthi, i-latitude yayo kumntla we-hemisphere iphakathi kwe-55th kunye ne-56th parallels) kunye ne-37° 36' 56" E (oko kukuthi, ubude bayo) ibekwe phakathi kwe-parallels 37 kunye ne-38 phakathi kwe-warps). Namhlanje, iindlela zokubeka satellite ezifana neGPS zisebenza kunye nesistim.
IGreenwich Meridian
Eyona ndlela yokwazi iGreenwich Meridian kukuya eLondon, owazalelwa eRoyal Greenwich Observatory, emazantsi ekomkhulu laseBritani. Le ndawo iyaziwa kancinci, kodwa yeyona ndawo ifanelekileyo yeholide yohambo oluya eLondon ngeentsuku ezi-3. IRoyal Greenwich Observatory yindawo ekubhekiselwa kuyo ekuqondeni ukuba kutheni kwaye kutheni iGreenwich Meridian ibonakala.
I-Royal Greenwich Observatory ibambe umboniso ngokubaluleka kwexesha, indlela eyakhiwe ngayo i-meridian, kunye nezivumelwano ezalandelwa ngamazwe kwihlabathi liphela ukumisela ithayimthebhile ngawo. Kwakhona, ukusuka kwi-promontory apho ukubonwa khona kungabonwa ngokungaqhelekanga kweLondon (ukuba nje kukho usuku olunelanga).
IGreenwich meridian isetyenziselwa ukuphawula ixesha eliqhelekileyo eliqhelekileyo. Le yindibano, yaye kwavunyelwana ngayo eGreenwich, kuba kwiNkomfa yeHlabathi eyayibanjwe ngowe-1884, kwamiselwa ukuba yimvelaphi yezero meridian. Ngelo xesha, uBukhosi baseBritani babukwelona xesha libalaseleyo lolwando, yaye kwakufuneka lwenjenjalo. Ukuba ubukhosi ngelo xesha bahluke, namhlanje siza kuthetha indawo eyahlukileyo, njenge-zero meridian. Ukuqala kwiGreenwich meridian, ummandla wexesha osebenza kwilizwe ngalinye kunye nommandla usetiwe.
Imeko kumazwe aseYurophu iyamangalisa kuba kukho iindawo ezininzi zexesha kwilizwekazi laseYurophu, kodwa ngokutsho kweSikhokelo 2000/84, amazwe abumba i-European Union agqibe kwelokuba agcine ixesha elifanayo kuzo zonke iindawo zokukhuthaza imisebenzi yezopolitiko neyorhwebo. . Esi siko sisetyenziswe kumazwe amaninzi ukususela kwiMfazwe yeHlabathi yokuQala, xa yayisetyenziswa njengendlela yokonga amafutha. Kodwa iGreenwich meridian isoloko isetyenziswa njengesalathiso.
Ukutshintsha kwexesha ebusika kwenzeka ngeCawa yokugqibela ngo-Okthobha kwaye kubandakanya ukuhambisa iwotshi phambili iyure enye. Kwelinye icala, utshintsho lwexesha ehlotyeni lwenzeka ngeCawa yokugqibela ngo-Matshi, oko kuthetha ukuhambisa iwotshi phambili iyure enye.
Indawo yokuzalwa yeGreenwich meridian yiLondon. Njengoko besichazile ngaphambili, le meridian idibanisa iNorth and South Poles, ngaloo ndlela ithatha amazwe amaninzi kunye namanqaku amaninzi. Umzekelo, iGreenwich meridian idlula kwisixeko saseSpain iCastello de la Plana. Olunye uphawu lokuhamba kweMeridian lufumaneka kwi-82.500 yeekhilomitha ze-AP-2 motorway e-Huesca.
Kodwa, enyanisweni, iMeridian ibaleka phantse kuyo yonke impuma yeSpain, ukusuka ekungeneni kwayo kwiiPyrenees ukuya ekuphumeni kwayo ngokucoca i-El Serrallo eCastellón de la Plana.
Ndiyathemba ukuba ngolu lwazi unokufunda ngakumbi malunga nokuba yintoni i-meridians kunye neempawu zabo.