Climate change will leave more and more people marooned on Scotland’s islands, industry leaders warned last night.

State-owned CalMac - the nation's main ferry operator - said its skippers were now facing longer and increasingly frequent storms amid what scientists say are dramatic changes in the wind systems over the North Atlantic.

The company has always had to call off some of its lifeline services because of bad weather - especially in the winter - but has warned passengers to expect more disruption this coming year and in the future

CalMac’s Captain Mark Thomson said: “As a major ferry operator delivering lifeline services in areas that experience some of the most challenging environmental conditions in Europe, we are increasingly aware of significant changes in prevailing weather conditions and their impact on our ability to deliver reliable services.

HeraldScotland: CalMac ferry

“In recent winters, our masters have witnessed an increase, not only in the severity of extreme weather events but also in their duration and frequency, all of which have impacted on our fleet's ability to operate services safely.

“Such extreme weather events also have a considerable impact on the ability of the ports and slipways we operate from to safely support the delivery of our ferry services.”

Problems relate to a complex climate system which brings wet and warm weather across the Atlantic to Scotland on westerly winds. Scientists call this the North Atlantic Oscillation or NAO.

READ MORE: Climate For Change: Scotland’s circular economy 

The prevailing winds have always been from the west, with some from the north-east in the spring.

However, as the NAO changes, skippers report encountering far more from the south and north.

Crucially, Scottish ports and harbours are located and designed to protect ships from westerlies.

Climate scientists and oceanographers have been concerned about these fluctuations, and on their impact on Scottish ferry services, for years.

Five years ago, an academic paper led by John Coll, of National University of Ireland, said: “Worsening storminess in the North Atlantic associated with future NAO changes has been proposed as a possible regional manifestation of wider global warming.

“For coastlines exposed to the long Atlantic fetch and the passage of deep depressions, the impacts could be considerable.”

Mr McColl and his colleagues, writing in the Journal of Applied Meterology and Climatology in 2013, added: "Allied to their influence on sea state, days with gales can also severely hamper ferry operations.

READ MORE: Campaigners: Climate Change Bill falls short 

“The sea state is sensitive to the NAO, and the winter wind climate of the region is also closely linked to the behaviour of the NAO. Any changes in the seasonality or frequency of deep cyclones have implications for transport infrastructure and other marine and coastal activities.

“With a disproportionately large increase in the risk of rough seas associated with an increase in mean wave height, ferry services could face increased levels of disruption.

"A deterioration of the wave climate through either natural variability or anthropogenic climate change could adversely affect the future economic development of the region."

Maritime sources say such predictions are starting to affect sailings.

Between January and the end of July this year, 2,326 out of 79,203 Calmac scheduled sailings were cancelled.

Of these, 327 were for mechanical reasons, amid criticism of decades-long under-investment in its fleet.

Most of the rest were because of bad weather.

Captain Thomson hinted that any rise in gale days - as well as change in gale directions - could have long-term costs for ferry providers.

Successive Scottish Governments have been accused of under-investing in ferries and ferry infrastructure, despite huge spending.

Captain Thomson said: "The safety of our vessels, crew, passengers and port facilities is our number one priority. Of course we fully appreciate our customers' frustration that weather changes are leading to an increase in disruptions across our network, but there is no quick fix to this and it will be a factor those responsible for replacing ships and upgrading harbours will have to take into account when planning for the future.”

The warning comes as world leaders gather in Poland for the Katowice Climate Change Conference.

It is the first to be held since the landmark Intergovernmental Panel on Climate Change report on limiting global temperature rise to 1.5C came out in October.

Scotland's First Minister Nicola Sturgeon is among those scheduled to attend.