Viernes, 22 Junio, 2018

Antarctica Starting To Turn Green

Antarctic moss banks Climate change is making Antarctica greener
Ramiro Mantilla | 19 May, 2017, 21:18

Soil samples from a 400-mile area along the northern part of the Antarctic peninsula found dramatic changes in growth patterns going back 150 years.

The leader of the research project said that it would lead to critical changes in the landscape of the peninsula and to its biology as well.

Plant life is growing rapidly due to climate change turning the continent green.

Various researchers from Exeter and Cambridge universities and the British Antarctic Survey carried out a study of 150-year old moss growth in the Antarctic Peninsula by analyzing the samples from the material laid down each year.

Previous studies have looked at the change in moss banks, but either only looked at one area of the peninsula or didn't look at change over a continuous timeframe, Amesbury said.

That is, from the original moss growth of 1 millimeter per year, the three moss banks showed evidence of a 4-millimeter growth annually.

People will think of Antarctica quite rightly as a very icy place, but our work shows that parts of it are green, and are likely to be getting greener.Even these relatively remote ecosystems, that people might think are relatively untouched by human kind, are showing the effects of human-induced climate change.

These "proxies" for temperature change include the vertical growth rate of the moss, how much mass it accumulates, and the amount of microbial activity - all of which tell researchers how that moss is responding to changes in temperature and water availability. They are going to study the severity of the effect before global warming was enhanced by human activities.

The results echo findings reported by the team in 2013 based on cores from the southernmost known moss bank, found on Alexander Island to the west of the Antarctic Peninsula.

"There is 0.34 per cent of the entire Antarctic continent that is predominantly ice-free", Dr Amesbury said.

Antarctica is a cold, harsh place.

"Antarctica is not going to become entirely green, but it will become more green than it now is", study leader Dr Matthew Amesbury told The Guardian. "The reason we think that this is a response driven by climate change is because of the very wide-scale impact we see across the whole of the Antarctic Peninsula".

"The likelihood of this happening is very much an uncertainty, but remains a very real possibility, which is understandably concerning", said Thomas Roland, a co-author of the study also from the University of Exeter.

The researchers said they'll continue to examine core records dating back over thousands of years to test how much climate change affected ecosystems before human activity started causing global warming.

"Although there was variability within our data, the consistency of what we found across different sites was striking", said Dan Charman, another author from Exeter.