A Green Island moss bank with icebergs © Matt Amesbury
Could the White Continent soon be the Green Continent? The finger is being pointed squarely at climate change for boosting the growth of plant life on Antarctica, meaning its cold and rocky landscape could become very different in the not too distant future.
"Temperature increases over roughly the past half century on the Antarctic Peninsula have had a dramatic effect on moss banks growing in the region," says Dr Matt Amesbury, of the University of Exeter. "If this continues, and with increasing amounts of ice-free land from continued glacier retreat, the Antarctic Peninsula will be a much greener place in the future."
Studying conditions on the extreme continent is difficult, with reliable temperature records only beginning in the 1950s, but by studying moss cores researchers from the Universities of Exeter and Cambridge, and the British Antarctic Survey were able to get data going much further back.
“We have looked at the relationship between moss growth and temperature change over the last c. 150 years,” says co-author Tom Roland to us in an email. “We’ve found that since approximately 1950 there has been a 4-5 fold increase in growth of these moss banks.”
So what does this mean for the Antarctic? “The expansion of these native moss ecosystems in and of itself is not necessarily a ‘good' or ‘bad’ thing,” says Roland, “it merely demonstrates that the effects of anthropogenic climate change can be seen even in the world’s most remote and pristine regions.”
Only 0.34 per cent of Antarctica is permanently ice-free, but with rising temperatures, increased precipitation, and tourism potentially introducing new flora, it could soon be a different story. Antarctica’s climate means it’s currently pretty tricky for plants to grow there – there are only two species of plants more complicated than moss on the Antarctic Peninsula, Antarctic hairgrass and Antarctic pearlwort – but as the moss expands into new, ice-free areas, and as conditions become more conducive for plant growth, it could allow invasive species to take hold.
“Although climatic conditions remain amongst the harshest on Earth for plant growth, plants and other organisms often still find a way to disperse and establish themselves,” adds Roland.
The impact of past temperature increases on moss growth indicates that Antarctica’s plants and soils could be significantly changed even by only small further increases in temperature, but the team plan to test this further by investigating moss data that goes back thousands of years to investigate growth before human intervention affected the ecosystem.