It is September. I am about to fly over the Amazon for the first time, on my way to speak on climate change and plastic pollution at the World Fair Trade Organisation Biennial conference.

I am anxious: these are challenging times for our fragile earth and the beating heart of our planet’s biodiversity. Blazing fires, a shrinking rainforest cleared to make way for 200 million head of cattle to satisfy the human craving for more and more meat, the last uncontacted human tribes staring up at a helicopter, shaking their spears. Not waving but drowning.

After half a day at 600 miles an hour high over the featureless blue of the Atlantic Ocean we finally fly over Georgetown, Guyana, splattered brown on green across the earth like a computer circuit board. A fleeting chessboard of fields … and something extraordinary and unexpected happens.

Ten thousand metres below the plane an emerald sea stretches as far as the eye can see in any direction without a single indication that human beings have ever existed. Lost in amazement, I stare through the tiny window for over twenty minutes, by which time we have covered more than two hundred wild wandering magical miles.

It is a world where tapirs barge thickly through undergrowth, monkeys howl the morning air, neon bright frogs crouch in flowers a hundred metres above the ground, butterflies languid the thick air, ants march brandishing leaves like flags, clouds balloon and pour, and rivers weave and weft, calving oxbow lakes in their wakes.

I am overwhelmed. Yes, it is threatened from all sides but, in spite of all our failings, the virgin forest still exists. We are not too late. Not yet.

When I returned from Peru, I offset the carbon emissions my trip had cost. The carbon cost is sobering and brings home the scale of the challenge. My 21,800 kilometre round trip produced 3.7 tonnes of CO2. It takes one tree around 40 years to sequester a tonne of carbon dioxide.

In 1998 it was calculated that to offset the carbon emissions of 23 million cars the UK would need to plant 14,300 square miles of poplar forest, 15 per cent of the entire rural land area of the country. There are now 32.5 million cars on British roads.

Here in York we have no rainforest. At 5 per cent, our tree cover is way below even our national average of 10 per cent. We do share our city with amazing biodiversity, however. Kestrels, hedgehogs and dragonflies, owls, deer, moths, swallows, and beetles. If we show imagination, desire and a readiness to invest in our future we can create new forests. The council can draw on the expertise of conservationists to identify locations and tree species, and enlist a citizen’s army of volunteers to help with planting. We can protect our environment and offset our carbon emissions.

Let’s go a step further. What if we plant our trees to the north of the city on land that feeds the River Ouse? Trees intercept rainfall, their leaves and branches catching the rain before it reaches the ground. Their roots increase the permeability of the soil and hold the earth together, preventing erosion and slowing rainwater run-off. Our new forests could offset carbon emissions, protect biodiversity, and alleviate flooding.

You might imagine the climate change committee is having a ball discussing such things, but the truth is that we are not. City of York Council, like many others up and down the country, still struggles to give the subject the attention and urgency it requires. As of now, the committee is bogged down in understanding why the city council cannot quantify the carbon cost of its operations. If you cannot measure your path to a zero carbon future you cannot deliver it. The basics have to be right.

I am proud of the committee. We have parked party politics and are working together to persuade the council to make systemic changes to the way it operates. The administration is listening.

It's hard transforming large organisations; people fear change. It's easier to trudge on, failing with dignity. But we owe it to our children to succeed. There is nothing to fear: a zero carbon future in a less polluted city with twice as many trees, powered by renewable energy, with properly insulated homes, a haven for biodiversity, and served by first class public transport, would be a good place to be!

We are not too late. We simply have to leave behind obsolescent practices and technologies. The Stone Age didn’t end because they ran out of stones.

Christian Vassie is chair of City of York Council's Climate Change Scrutiny Committee