Key environment groups have called on the Brazilian government to do more to protect the endangered Amazon rainforest after satellite images have revealed a massive pocket of illegal logging and adverse agricultural development.

Images released on Saturday (Friday local time) for the 12 months through to the end of July this year showed 7900 square kilometres of forest in the Amazon has been cleared, up 13.7 per cent on the previous year.

While the number is less than the Amazon’s deforestation of the early 2000s, scientists consider the rainforest as one of nature’s best protections against global warming, as it acts as a giant carbon “sink” by absorbing the gas.

The jungle is also rich in biodiversity, hosting billions of species yet to be studied.

Greenpeace and Brazil’s Climate Observatory – a network of non-government organisations – have condemned the latest revelations and are calling on the Brazilian government to increase its policing of the jungle.

Greenpeace’s Marcio Astrini said the Brazilian government had not done enough to fight deforestation and recent policy moves such as ones reducing areas under federal protection fuelled environmental destruction.

Deforestation is a key factor behind global warming, accounting for around 15 per cent of annual emissions of heat-trapping gases, similar to that of the transportation sector.

Brazil’s environment minister Edson Duarte said that illegal logging was the main factor behind the increase in deforestation in the Amazon.

He called on the government to increase its policing of the jungle.

The Climate Observatory said the increase also caused by Brazil’s growing commodities sector as farmers sought to expand.

Both groups said they were worried that deforestation could increase further during the government of President-elect Jair Bolsonaro, 63, due to take office in January.

The retired military officer has sharply criticised the Brazilian environmental protection agency, and the agriculture sector is one of his main political bases.

According to National Geographic, the Amazon may already be at a “tipping point”, as Mr Bolsonaro wants to build more roads and carve out greater areas for the country’s soy and cattle producers.

Scientists say he wants to “triple” deforestation in the 3.8 million square km of the Amazon, which would impact water supplies in Brazilian cities and speed up the decline of the rainforest.

“The region has been so degraded that even a small uptick in deforestation could send the forest hurtling toward a transition to something resembling a woodland savanna,” National Geographic said.

Despite the recent rise, deforestation remains sharply below the levels recorded in the early 2000s, before the Brazilian government launched a strategy to fight forest destruction.

In 2004, for example, more than 27,000 square km were cleared, an area the size of Haiti.

These 7900 square km of forest cleared is equivalent to more than half the territory of Jamaica.

-with AAP