Život
Nova mjerenja pokazala su da se led u moru oko Antarktike rapidno topi. To je golemi problem za klimatski sustav
Antarktika je u četiri godine izgubila istu količinu leda koju je Arktik izgubio u 34 godine
Piše Vedran Vrabec 82 preporuka 02. 07. 2019.
Ranging in color from snow white to turquoise, sea ice lined the shoreline in eastern Greenland in mid-June 2000. NASA's Landsat 7 satellite acquired this image on June 16, 2000, shortly before the summer solstice when the Arctic enjoyed near round-the-clock sunshine. Although snow and ice abound in this image, both are in retreat for the summer. Snowcaps form dendritic patterns on the brown landscape, leaving south-facing slopes especially bare. Around the Hold with Hope promontory, fast ice clings to the shoreline. Common over shallow ocean waters along shorelines, fast ice holds fast to the shore and/or sea bottom, not moving with winds or currents. Off the coast, pieces of bright white sea ice float on the sea surface, able to move with forces that don's affect the fast ice. Much of the fast ice in this image is blue, especially in the fjord north of Hold with Hope. Summer melt often lends ice a blue color due to water saturation. In addition, this ice could be what is known as blue ice, or ice composed of large crystals. Light that is visible to human eyes is composed of three basic components: red, green, and blue. Pure ice absorbs a miniscule amount of red light, reflecting slightly more green and blue light. This red-light absorption is lost in the noise of tiny snow crystals, the same way a piece of colored hard candy might appear white if it were pulverized. Large ice crystals make the red-light absorption visible to human eyes, just as sufficiently large pieces of glass would show a very subtle tint. The relentless action of wind can transform snow crystals to large ice crystals. Away from the coast, snakes of ice make their way through inland fjords, and some of this ice is also blue.
Život
Kada ćemo ovo shvatiti ozbiljno? Količina arktičkog leda druga je najniža u povijesti mjerenja
Svake godine mjeri se najmanja godišnja količina leda na Arktiku, podaci su zabrinjavajući
Piše Željka Orešković 2 preporuka 26. 09. 2019.
(FILES) This file photo taken on November 11, 2016 shows an image obtained from NASA showing the Antarctic Peninsula's rift in the Larsen C ice shelf from NASA's IceBridge mission Digital Mapping System. A trillion-tonne iceberg, one of the biggest on record, has snapped off the West Antarctic ice shelf, said scientists on July 12, 2017, who have monitored the growing crack for months. "The calving occurred sometime between Monday, July 10 and Wednesday, July 12, when a 5,800-square kilometre (2,200-square mile) section of Larsen C (ice shelf) finally broke away," the Swansea University said in a statement. / AFP PHOTO / NASA's Goddard Space Flight Center / HO / RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT AFP PHOTO /NASA's Goddard Space Flight Center - NO MARKETING - NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS
Život
Ovo je, realno, vijest dana: od Antarktike se odvojio jedan od najvećih ledenjaka u povijesti
Blok leda je veličine 6000 četvornih kilometara
Piše Vuk Oreb 470 preporuka 12. 07. 2017.
Vijesti

Još ne vjerujete u klimatske promjene? E pa Arktik bi u rujnu mogao prvi put u povijesti ostati bez leda

Mjerenja pokazuju da je rujan mjesec s najmanjom količinom plutajućeg leda

Fishermen boats sail out of Svolvaer harbour in Lofoten Islands, on March 2, 2024. (Photo by Olivier MORIN / AFP)
FOTO: AFP
08. 03. 2024.

Američki znanstveni tim procijenio je da bi Arktik u rujnu mogao biti bez leda, prvi put otkad postoje mjerenja, a to bi se moglo dogoditi već ove godine, objavljeno je u časopisu Nature Reviews Earth & Environment.

Između 2035. i 2067., Arktik bi u rujnu mogao u pravilu stalno biti bez leda, doznaje se iz istraživanja koje je provelo Sveučilište Colorado u Boulderu, predvođeno Alexandrom Jahn.

U studiji se objašnjava da bi pojedinačni događaji, poput neuobičajenog zatopljenja tijekom nekoliko tjedana, mogli rezultirati gubitkom leda u rujnu, već ove ili narednih godina.

U rujnu najmanja količina plutajućeg leda

Mjerenja pokazuju da je rujan mjesec s najmanjom količinom plutajućeg leda. Tijekom 80-ih godina prošlog stoljeća, u rujnu je u pravilu ledom bilo pokriveno 5,5 milijuna četvornih kilometara Arktičkog oceana.

Otkad su 1978. počela mjerenja, to područje se smanjuje za prosječno 78.000 četvornih kilometara godišnje. Međutim, unatoč klimatskim promjenama, ledeni pokrov oceana na Arktiku se posljednjih godina blago povećava.

“Sve u svemu, atmosferska varijabilnost čini 75 posto unutarnje varijabilnosti leda u Arktičkom oceanu. Količina leda stoga uvelike ovisi o vremenskim uvjetima i, u manjoj mjeri, toplim vodama koje dolaze iz susjednih oceana”, zaključuje se u studiji.

klimatske promjene, klima, globalno zatopljenje, led, Arktik, ledenjaci,