Monday, January 10, 2011

Climate change to go on for at least “1,000 years”

[Left: At the South Pole lies the An­tar­tic Ice Sheet, shaded in red in the above di­a­gram. It is con­si­dered vu­lner­able to melt­ing due to glob­al warm­ing (Cred­it: NA­SA/GSFC Sci­en­tif­ic Vis­u­al­i­za­tion Stu­dio)]

Courtesy University of Calgary and World Science staff

Ris­ing car­bon di­ox­ide lev­els in the Earth’s at­mos­phere will cause un­stop­pa­ble changes to the cli­mate for at least the next 1,000 years, a new study sug­gests.

The find­ings have led re­search­ers to es­ti­mate a col­lapse of the West Ant­arc­tic ice sheet by the year 3000, and an even­tu­al rise in the glob­al sea lev­el of at least four me­tres (yards).

The stu­dy, to ap­pear in the Jan. 9 ad­vance on­line edi­tion of the re­search jour­nal Na­ture Ge­o­sci­ence, is billed as the first full cli­mate mod­el sim­ula­t­ion to make pre­dic­tions so far ahead. It’s based on best-case, “zero-emis­sions” sce­nar­i­os sim­ulated by sci­ent­ists from the Ca­na­di­an Cen­tre for Cli­mate Mod­el­ling and Anal­y­sis at the Uni­vers­ity of Vic­to­ria, and at the Uni­vers­ity of Cal­ga­ry, al­so in Can­a­da.

“We cre­at­ed ‘what if’ sce­nar­i­os,” said re­searcher Shawn Mar­shall of the Uni­vers­ity of Cal­ga­ry. “What if we com­pletely stopped us­ing fos­sil fu­els and put no more [car­bon di­ox­ide] in the at­mos­phere? How long would it then take to re­verse cur­rent cli­mate change trends and will things first be­come worse?” Read More