According to a new study by researchers from the University of Exeter, climate change could lead to sudden changes in the amount of vegetation grown in various parts of Great Britain.
The researchers used models to analyze the local impacts of two different climate change scenarios at a scale of 1.5 x 1.5 km, studying the country in high resolution. The results revealed that even a “smooth” climate change could cause abrupt shifts in the amount of vegetation in certain places.
A majority of such shifts were increases, brought about by factors like wetter, warmer conditions and more carbon dioxide (CO2) in the atmosphere, fertilizing plant growth. In other places, warmer conditions could lead to drying out of the soil, resulting in the rapid reduction of plant productivity and a quick decline in vegetation.
According to Dr Chris Boulton, from the Global Systems Institute at the University of Exeter, “The general expected trend towards warmer, wetter weather is likely to cause an overall increase in vegetation in temperate places like Great Britain. However, we wanted to find out whether even ‘smooth’ climate change might lead to abrupt shifts in vegetation.”
A lot of research has focussed on ‘tipping points’ in large systems like rainforests and oceans. Our study doesn’t predict abrupt shifts across the whole of Great Britain—0.5-1.5% of the land area depending on the climate scenario—but it shows numerous shifts can happen on a localised level.
Dr Chris Boulton, Global Systems Institute, University of Exeter
A new technique was employed by the researchers to identify “abrupt” changes to look for sudden shifts in the total amount of carbon stored in vegetation over a short span.
“We also find early warning signals before some of the abrupt shifts. This is good news as it shows the potential for being able to predict them in the real world,” added Dr Boulton.
GSI Director Professor Tim Lenton stated, “We didn’t expect to see hundreds of localised abrupt shifts in the projections.”
Up to now, climate-driven abrupt shifts in vegetation have been rare in Great Britain. Our results should not be taken as specific predictions of where abrupt ecosystem change will happen. But they serve to illustrate that it could happen across Great Britain in a changing climate.
Tim Lenton, Professor and Director, Global Systems Institute, University of Exeter
For the study, two climate scenarios developed by the Met Office were employed. The study titled “Abrupt changes in Great Britain vegetation carbon projected under climate change” was financially supported by the Valuing Nature Programme and published in the Global Change Biology journal.
Boulton, C. A., et al. (2020) Abrupt changes in Great Britain vegetation carbon projected under climate change. Global Change Biology. doi.org/10.1111/gcb.15144.