Luke Dawson, a National Trust ranger who helps look after the site, says heavier winter rains are washing chalk from the slope more quickly, while mild, damp conditions give algae more chance to grow.
He says this wetter weather has been having “a dulling effect” on the Giant’s outline, leaving it greener and less distinct between maintenance work.
The Trust is cautious about attributing the changes directly to climate change at a single site.
“It’s one of these things we cannot really prove,” says Dawson. “It is more just observation of what we are seeing up there.”
The charity has cared for the Giant since 1920. Its rangers and volunteers keep the outline defined by rechalking the figure every decade or so to protect it from weeds and erosion. And between chalking it uses sheep to keep the grass short.
But the Trust says that coupled with heavier winter rains, the frequent dry spells in summer, mean the grass grows back more slowly and can leave the chalk edges more exposed and vulnerable to erosion.
The world is now about 1.4C warmer on average than in the late 19th Century, largely because of human activities such as burning fossil fuels.
The Met Office says the UK’s climate is already notably different from even just a few decades ago and it expects the trend towards warmer wetter winters and hotter drier summers to continue.
On Thursday, it published a new report, external which warns there is an almost nine in ten chance the world will see a new record temperature within the next five years.
National Trust says these changes mean the Giant may need more frequent attention than every decade to ensure he does not lose his defining features.
His latest makeover has come after just seven years.
