Melt­ing glaciers

The Jerusalem Post - The Jerusalem Post Magazine - - CONTENTS - • By IT­SIK MAROM

Glaciers are spec­tac­u­lar nat­u­ral phe­nom­ena and have been part of the Earth for eons. Their icy white and blue-look­ing ex­panse are eye-catch­ing and beau­ti­ful. Yet most peo­ple liv­ing to­day have never seen one in real life. That’s be­cause glaciers de­velop in very cold and hos­tile en­vi­ron­ments, mainly near the poles of the planet or in high moun­tains and places that are not com­fort­able to live in. Most peo­ple spend their lives closer to the equa­tor. Pop­u­la­tions get smaller as you go far­ther to­ward the ex­treme north or south.

A glacier builds it­self slowly and re­quires only three in­gre­di­ents: time, pre­cip­i­ta­tion and cold tem­per­a­tures. The process be­gins with an ac­cu­mu­la­tion of snow in a large enough area. Since the snow is bright and white, the sur­face then re­flects the sun’s rays by send­ing them away from it like a mir­ror. So in ad­di­tion to de­vel­op­ing in a cold zone, no warmth gets to the in­cip­i­ent glacier. In time, many lay­ers add on to the orig­i­nal ones and ice starts to form. Along the years and the count­less sea­sons, the ice lay­ers con­dense and get thicker and thicker un­til a glacier is formed.

Once it is formed, like al­most ev­ery­thing in na­ture, the glacier starts grow­ing, mov­ing and spread­ing it­self to­ward its sides. Don’t for­get, snow con­tin­ues to fall on top of the glacier and its weight pushes it down.

Fi­nally, typ­i­cal of na­ture, bal­ance is achieved. The spread­ing of a glacier stops or is lim­ited by reach­ing an area of higher tem­per­a­ture like the lower slopes of a moun­tain, or reach­ing a large body of wa­ter, such as a large lake, sea or ocean. Here the borders of the glacier are melt­ing. The ice is made of wa­ter and as such, the glacier is mov­ing but very slowly, un­der its own pressure.

At the poles, North Pole and Antarc­tica, sea wa­ter freezes and forms float­ing glaciers that also feed from fall­ing snow. This ice sheet ex­pands and re­duces ac­cord­ing to the sea­sons. Of cen­tral im­por­tance to this nat­u­ral world, the game is bal­ance, as it is in many as­pects of na­ture.

Re­cently we have been wit­ness­ing a phe­nom­e­non that dis­turbs the nat­u­ral bal­ance: melt­ing glaciers. Ev­ery­body has heard of global warm­ing. While con­cen­trat­ing on the ef­fect on the gla­cial world, we can say that one of the key in­gre­di­ents is chang­ing. Cold tem­per­a­tures are not cold enough any­more, which re­sults in melt­ing ice.

The on­go­ing melt­down starts a chain re­ac­tion be­cause the bal­ance is lost. One of the ad­van­tages of glaciers for the Earth is that this white and bright sur­face of ice re­flects around 10% of the en­ergy that it gets from the Sun right back to the sender. This gets rid of a good amount of heat that oth­er­wise would ab­sorb into the Earth. Smaller ice sur­faces means more heat on Earth, which in turn causes more gla­cial melt­ing. The melt­ing glaciers be­come wa­ter again, which then gets to the oceans and raises the wa­ter level all over the Earth.

Ris­ing wa­ter lev­els put at risk large hu­man pop­u­la­tions that live along the coasts. The ris­ing of wa­ter by one to two me­ters is ex­pected by the end of the cen­tury. Flat coun­tries like Bangladesh, Hol­land and small is­lands in the oceans will be first to be se­verely af­fected in the be­gin­ning of the melt­ing process. Also to be con­sid­ered is the mass of ice that is packed and stored in the Antarc­tic alone. If it all melts, the oceans’ wa­ter sur­face will likely rise by al­most 60 me­ters – a ma­jor global dis­as­ter. Even now, sci­en­tists ex­pect that the wa­ter ris­ing will leave more than a bil­lion refugees by the end of cen­tury.

Much more of course will hap­pen in the nat­u­ral world as a re­sult of global warm­ing that will ef­fect ev­ery­thing and ev­ery form of life on Earth. We have to hope that com­mon sense, along with deep think­ing, will re­duce the on­go­ing prob­lem. We must keep our en­ergy-re­flect­ing shields as big and safe as pos­si­ble; oth­er­wise the hu­man race may need to find an­other place to live in the Milky Way Galaxy.

Glaciers are ma­jes­tic and beau­ti­ful. Once you see them, you will fall in love and be awed by their pres­ence. When they are healthy, the world is smil­ing, and we cer­tainly want and need this smile to con­tinue.

Clock­wise from up­per left: Per­ito Moreno Glacier in Ar­gen­tinian Patag­o­nia. Men­den­hall Glacier near Juneau, Alaska. Ni­gards­breen Glacier in Nor­way. Columbia Glacier near Valdez, Alaska. Exit Glacier near Seward, Alaska. A sign marks its lo­ca­tion 14 years ago. Glaciers along Prince Wil­liam Sound, Alaska. Bro­ken blue ice float­ing away from the Columbia Glacier.

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