Saturday 10 August 2013

Global warming


Warming driving fish toward poles at alarming speed: study
Con­tra­ry to pre­vi­ous think­ing, ma­rine spe­cies are head­ing to­ward the poles as the cli­mate warms—and do­ing so more than 10 times faster than land crea­tures, a re­port says.


5 August, 2013


The lead­ing edge or front-line of ma­rine spe­cies dis­tri­bu­tions is mov­ing to­ward the poles at an av­er­age of 72 km [45 miles] per decade,” com­pared to 6 km for land spe­cies, said El­vi­ra Po­lo­czan­ska, the lead au­thor.

This is oc­cur­ring even though sea sur­face tempe­ratures are warm­ing three times slower than land tempe­ratures,” added Po­lo­czan­ska, a re­search sci­ent­ist with Aus­trali­a’s na­t­ional sci­ence agen­cy, the Com­mon­wealth Sci­en­tif­ic and In­dus­t­ri­al Re­search Or­ga­nisa­t­ion.

Oceans cov­er 71 pe­rcent of Earth’s sur­face, but our knowl­edge of its re­sponses to cli­mate change is far less than for land habi­tats. The new re­port, pub­lished in the jour­nal Na­ture Cli­mate Change, is de­signed to help cor­rect that de­fi­cien­cy.

The vast blue deep is “a to­tally dif­fer­ent sys­tem with its own un­ique set of com­plex­i­ties and sub­tleties,” said Ca­mille Parme­san of the Uni­vers­ity of Tex­as at Aus­tin, one of the re­search­ers. Yet the im­pact is sim­i­lar: “an over­whelm­ing re­sponse of spe­cies shift­ing where and when they live in an at­tempt to track a shift­ing cli­mate.”

The sci­ent­ists, from 17 in­sti­tu­tions world­wide, gath­ered da­ta from se­ven coun­tries to cre­ate a da­tabase of 1,735 changes in ma­rine life from re­search lit­er­a­ture. The changes were doc­u­mented with an av­er­age length of 40 years of ob­serva­t­ion.

This is the first com­pre­hen­sive doc­u­menta­t­ion of what is hap­pen­ing in our ma­rine sys­tems in rela­t­ion to cli­mate change,” Parme­san said. “Far from be­ing a buff­er and dis­play­ing more mi­nor changes, what we’re see­ing is a far stronger re­sponse from the oceans.”

The larg­est shifts were found for plank­ton and bony fish, which are most fish. Re­search­ers al­so found that the tim­ing of spring events in the oceans had ad­vanced by more than four days, nearly twice the fig­ure for land

1 comment:

Note: only a member of this blog may post a comment.