Helston has been urged to "declare a climate emergency" and begin immediate steps to reduce the effects of global warming.

The town council was visited by members of Transition Helston, which wants to see the area become less dependent on fossil fuels and more self-reliant in areas such as transport, energy and food.

Catherine Lewis, who lives in Helston, quoted from a report by the Intergovernmental Panel on Climate Change (IPCC) last October, which gave just 12 years to "avoid climate catastrophe."

Ms Lewis, a local teacher, said: "If we do not act, our children's futures are bleak."

She said the report stated that global warming must be stopped at 1.5°C above pre industrial levels - currently on track to be breached by 2030 - as if it rose by 2°C, which it is predicted to reach by 2045 if nothing changes, twice as many people in the world would face water scarcity and 1.5 billion people would be exposed to deadly heat extremes.

She stressed: "We will not be immune to climate change here in Cornwall. It will affect us too."

Ms Lewis explained that rising temperatures would make it increasingly difficult to grow grains and other food crops, and that insects pollinating the crops would die.

"Within Cornwall there are 27 locations that are at significant risk from flooding or coastal erosion," she added.

Ms Lewis told councillors: "We can still mitigate some of the change that is coming. But we need to act and we need to act now.

"Please declare a climate emergency. Commit to making Helston carbon neutral by 2030. Call on Westminster and Cornwall Council to provide the powers and resources to make the 2030 target possible."

Also speaking was John Marshall, who said he had seen a visualisation showing the floor of Truro Cathedral being covered in water by the end of this century.

He said the world now need to reduce the amount of carbon dioxide being emitted and find ways to draw the gas down from the atmosphere.

Local councils could help by planting trees, encourage solar panels and reduce food miles by promoting locally produced food.

Helston's mayor John Martin agreed "we all have concerns" and said he would be organising a discussion on the subject following the outcome of Tuesday's meeting of Cornwall Council, when the members will be asked to prepare a report within six months, setting out how Cornwall can sufficiently reduce carbon emissions to play a part in limiting global warming to 1.5°C above pre industrial levels.

He said he wanted to hear the countywide strategy before taking it further in Helston.

Members of the Transition Cornwall Network are also visiting other town and parish councils in Cornwall, with Stithians already having declared an emergency and Ladock setting up a sub-committee to plan for climate change.