David Attenborough warning on climate change, page-267

You mention trees as the solution to curb CO2 emissions.

That sounds good in theory but is it practical?

Here is a bit of arithmetic.

Humans currently emit 40 billion tonnes of CO2 each year.

If we want plants to absorb only 10% of the CO2 produced then based on a conservative 2 trees to capture a tonne of co2 we need to plant

8 billion trees each year.

If each tree needs 10 sq. m of space then we need an area of

8,000,000,000 x10 sq Km
1000x1000

• That is 80,000 sq. km annually
• But the world clears or burns 130,000 sq. km of forest each year.

So to balance the books we need to plant 130,000 +80,000 = 210,000 sq. Km annually or stop clearing forests.

This is almost the area of Victoria needed each year.

Given the best land is already used for crops then the trees will be planted in areas where there are poorer or drier soils.

Meanwhile we need to develop new technologies to suck up CO2 and turn it into carbon based materials such as wood, fibres, food and construction materials.