Cruise ships and their destination ports are heading for some huge changes in coming years as the industry prepares to handle climate change and overtourism, the biggest gathering of travel agents in the Southern Hemisphere heard in Sydney today.

Adam Goldstein, chair of Cruise Lines International Association (CLIA) and Vice Chair of Royal Caribbean, told CLIA Australasia’s Cruise360 that 30 million passengers would cruise by the end of 2019.

He also predicted 40-45 million would be on board ships by 2030.

But this enormous growth is now set against the growing worry over the effects of travel on the planet, and on local destinations like Venice and Dubrovnik.

Cruise represents just two per cent of tourism, so looking ahead at other tourism operators is also important.Cruise sustainability

There could be eight billion air travellers in the years ahead, putting further pressure on climate change and destinations unless the growth is properly managed.

Mr Goldstein said concern over increasing tourism was already manifesting itself in Europe and, as millennial and Gen Z travellers increase, this will spread.

But amazing changes are already underway to meet the demands of governments and oversight bodies.

Almost all cruise companies had signed up to reduce emissions by 40 per cent by 2030, and by 70% by 2050.

This would spur huge research projects, some of which are already underway, to make ships as close to having zero emissions as possible.

Water treatment plants, the banning of single-use plastics, LNG fuels and zero discharges and zero waste to landfill were becoming commonplace.

Partnerships with destinations and climate change bodies meant cruise lines were leading contributors to preservation and the creation of new travel experiences, from water purification to bubbles under the hulls of megaliners to help them move more smoothly through water.

And he said partnerships with towns like Eden in NSW, were cruising this season is set to take off, were important to ensure that everyone shares in cruise’s $5 billion of economic benefits.

Australia holds the world record for cruise market share at 5.8 per cent of the population, which explains why today’s conference saw talks from some of the industry’s world leaders.