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Thousands of square miles of rainforest is cleared in the Amazon each year to make way for farming land - a pattern of destruction that takes place all around the world.

But despite this, the world has got greener in the past decade, with the total amount of plant coverage increasing overall.

The increase is so noticeable that the world's trees and plants now store almost 4 billion more tonnes of carbon than they did in 2003. 

Thousands of square miles of rainforest is cleared in the Amazon (pictured) each year to make way for farming land - a pattern of destruction that takes place all around the world - but despite this, the planet has got greener in the past decade, with the total amount of plant coverage increasing overall

This is thanks to tree-planting in China, forest regrowth in former Soviet states because of abandoned farms and more lush savannas because of abandoned farms and higher rainfall.

Scientists analysed 20 years of satellite data and found an increase in carbon, despite ongoing large-scale tropical deforestation in Brazil and Indonesia, according to research published on Monday in Nature Climate Change.

Carbon flows between the world's oceans, air and land. It is present in the atmosphere primarily as carbon dioxide (CO2) - the main climate-changing gas - and stored as carbon in trees.

Through photosynthesis, trees convert carbon dioxide into the food they need to grow, locking the carbon in their wood.

The greening of Earth is thanks to tree-planting in China, forest regrowth in former Soviet states because of abandoned farms and more lush savannas because of abandoned farms and higher rainfall. An an image of a family on a farming collective in the USSR in 1935 is shown

While the four-billion-tonne increase is helpful, it is minuscule compared to the 60 billion tonnes of carbon released into the atmosphere by fossil fuel burning and cement production over the same period, said Yi Liu, the study's lead author and a scientist at the University of New South Wales.

'From this research, we can see these plants can help absorb some carbon dioxide, but there's still a lot of carbon dioxide staying in the atmosphere,' Dr Liu said by telephone from Sydney.

'If we want to stabilise the current level of carbon dioxide in the atmosphere - and avoid the consequent impacts - it still requires us to reduce fossil fuel emissions.'

Dr Liu, who specialises in observing the water cycle including rainfall and soil moisture, used a new technique of collecting satellite data on radio frequency radiation naturally emitted by the Earth to calculate the amount of vegetation in a given area.

Before, scientists measured vegetation through satellite images and other techniques, looking at canopy greenness and plant height.

China has had tree-planting projects for two to three decades and is now boosting the Earth's greenery, researchers say. Here, Two giant pandas rest at a panda park on the outskirts of Chengdu, capital of China's southwestern Sichuan province

He had expected to find increased forests in China, which has had tree-planting projects for two to three decades, as well as on abandoned farmland in former Soviet countries.

But he was surprised to discover the large expansion in vegetation due to higher rainfall on tropical savannas and shrublands in Australia, Africa and South America.

But these fragile gains may be easily lost, as weather patterns shift with climate change, he warned.

'Savannas and shrublands are vulnerable to rainfall – one year can be very wet, and more carbon will be fixed in plants, but the next year can be very dry, and then we will lose the carbon fixed in previous years,' Dr Liu explained.

Louis Verchot, a research director at the Indonesia-based Centre for International Forestry Research, said Dr Liu's findings were 'by and large what we would expect in the warmer and wetter world that results from climate change'.

Researchers found a large expansion in vegetation due to higher rainfall on tropical savannas and shrublands in Australia, Africa and South America. The Savannah, Serengeti National Park, Tansania, East Africa is pictured

'As ice and permafrost melt, they are being replaced by vegetation, and the tree line is moving north as the Arctic warms,' he said by email.

Vegetation growth is also expected to increase due to rising CO2 in the atmosphere, known as the 'CO2 fertilisation effect'.

Dr Verchot said the value of Dr Liu's study is that it puts a number on the contribution of vegetation to moderating greenhouse gas accumulation in the atmosphere.

'Hopefully this will lead to greater efforts to stop tropical forest loss and to promote sustainable use of ecosystems in ways that preserve enough of the carbon absorption function as we continue to pump CO2 into the atmosphere through fossil fuel burning,' Dr Verchot added.