If all the extra leaves growing because of increased CO2 in the atmosphere were laid end to end, it would cover a space twice the size of the continental U.S.

That's the conclusion of a new study conducted by 32 scientists and 24 institutions.

BBC:

Climate sceptics argue the findings show that the extra CO2 is actually benefiting the planet.

But the researchers say the fertilisation effect diminishes over time.

They warn the positives of CO2 are likely to be outweighed by the negatives.

The lead author, Prof Ranga Myneni from Boston University, told BBC News the extra tree growth would not compensate for global warming, rising sea levels, melting glaciers, ocean acidification, the loss of Arctic sea ice, and the prediction of more severe tropical storms.

The new study is published in the journal Nature Climate Change by a team of 32 authors from 24 institutions in eight countries.

It is called Greening of the Earth and its Drivers, and it is based on data from the Modis and AVHRR instruments which have been carried on American satellites over the past 33 years.The sensors show significant greening of something between 25% and 50% of the Earth's vegetated land, which in turn is slowing the pace of climate change as the plants are drawing CO2 from the atmosphere.

Just 4% of vegetated land has suffered from plant loss.

This is in line with the Gaia thesis promoted by the maverick scientist James Lovelock who proposed that the atmosphere, rocks, seas and plants work together as a self-regulating organism. Mainstream science calls such mechanisms "feedbacks".

The scientists say several factors play a part in the plant boom, including climate change (8%), more nitrogen in the environment (9%), and shifts in land management (4%).

But the main factor, they say, is plants using extra CO2 from human society to fertilise their growth (70%).

Harnessing energy from the sun, green leaves grow by using CO2, water, and nutrients from soil.

"The greening reported in this study has the ability to fundamentally change the cycling of water and carbon in the climate system," said a lead author Dr Zaichun Zhu, from Peking University, Beijing, China.

The authors note that the beneficial aspect of CO2 fertilisation have previously been cited by contrarians to argue that carbon emissions need not be reduced.

Short version of thesis: Rising levels of carbon emissions are good for the planet, except when they aren't.  I find it fascinating that faced with this evidence, these climate scientists insist that the contrary is true.

Who are the deniers now?

Models predicting temperature rise have been spectacularly wrong.  Models have also predicted a much larger rise in levels of CO2 in the atmosphere than have actually occurred.  And yet, climate hysterics are insisting we destroy our economies, taking trillions of dollars over the next 30 years, transferring it to poor countries to pay for our climate sins.

Despite the size of this study, it will likely be buried by climate change activists because it inconveniently shows how wrong they are.