BRAZIL (AFP) -- With fierce blazes raging in jungles from the Amazon to Indonesia, concerns are mounting about the impact as rainforests play a vital role in protecting the planet against global warming. The latest serious outbreak is in Indonesia, where smog-belching fires started to clear land for agriculture are burning out of control, blanketing the region in toxic smog. Why are rainforests important in fight against global warming? Mankind’s reliance on fossil fuels usually receives much of the blame for climate change but scientists say that deforestation has also played a big role. Forests are natural buffers against climate change, as they suck greenhouse gas carbon dioxide out of the atmosphere. But forests worldwide have been logged on an industrial-scale over the decades for timber and to make way for agricultural plantations. Burning of large expanses of trees also releases huge amounts of carbon dioxide. At the peak of Indonesia’s 2015 forest fires -- the worst in the country for two decades -- the country spewed more greenhouse gases into the atmosphere each day than all U.S. economic activity for the same period, according to environmental watchdog the World Resources Institute (WRI). How much of Indonesia’s rainforests have been destroyed? Greenpeace estimates that in the past 50 years, more than 74 million hectares (182 million acres) of Indonesia’s biodiverse rainforests -- an area twice the size of Germany -- have been chopped down, degraded or burned. They have often been destroyed to make way for plantations for the lucrative palm oil and pulpwood industries, particularly on Sumatra and Borneo islands, with fires often started illegally to clear land. Indonesia suffers forest fires annually but this year’s appear to be the worst since 2015. The country’s disaster agency estimates that from January to August, about 328,000 hectares (810,000 acres) of land was burned. The country has however managed to slow the rate of deforestation in recent years. Why are they burning and can it be stopped? Farmers and plantation owners are usually blamed for starting the fires as a quick and cheap way to clear land. Major companies typically deny starting blazes and instead point to small-scale farmers and villagers. The most serious fires occur in peatlands, which are highly combustible when drained of water to be converted into plantations. The situation this year has been worsened by drier weather in Indonesia. Authorities have deployed thousands of security forces to battle the blazes but most believe only the start of the rainy season -- usually in October -- will douse them.