A few weeks ago, Unknown Country reported that NASA were investing millions of dollars into a new laser-based instrument, located on the International Space Station, which is intended to provide a unique 3-D view of Earth’s forests. The focus of its mission is to provide definitive information about the role of forests in the carbon cycle, and as such, in global warming.
The laser, known as the Global Ecosystem Dynamics Investigation (GEDI) lidar, the instrument will be the first to systematically probe the depths of the forests from space, and assess how they affect our weather systems and other ecosystems.
One of its most important targets must surely be the Amazon Rainforest. Whilst it is not the largest area of forest in the world, the Amazon Rainforest is the world’s largest area of biodiversity, being home to one quarter of all known terrestrial species, and so it is intensely important in environmental terms. It is also known to be a hugely significant repository for excess carbon dioxide in the atmosphere, absorbing around 2 billion tons per year. The fate of the rainforest of major global oncern, yet it is gradually being eroded by deforestation and drought. After two serious droughts in 2005 and 2010, Brazilian scientists have discovered that the Amazon rainforest has degraded to the point where it is losing its ability to play a role in weather regulation, and that the recent droughts may have been exacerbated by logging and burning in the forest.
The study, which was led by Antonio Nobre, a researcher in the government’s space institute, Earth System Science Centre, is a summary of over 200 existing papers focusing on Amazonian climate and forest science. Nobre hopes that the findings of the study will act as a "wake up call" for the world, highlighting the sheer magnitude of the issue:
“I realised the problem is much more serious than we realised, even in academia and the reason is that science has become so fragmented. Atmospheric scientists don’t look at forests as much as they should and vice versa,” said Nobre in a report of the study. “It’s not written in academic language. I don’t need to preach to the converted. Our community is already very alarmed at what is going on.”
Not only does the Amazon host thousands of living species and absorb harmful greenhouse gases, but it also acts as a pump that channels much-needed moisture inland via rivers and the huge rainclouds that tend to form over the forest, hence its name. It also provides physical protection against severe weather such as tornadoes and hurricanes. Yet it is being lost at an astonishing rate: over the past two decades, an area twice the size of Germany has vanished due to degradation, drought-fuelled fires, or deforestation. The problem is now becoming a vicious cycle, as the dwindling forest areas cause further water shortages and droughts in the area.
The report warns that the “vegetation-climate equilibrium is teetering on the brink of the abyss.” It revealed that this October, which normally heralds the beginning of the rainy season, was the driest on record since 1930, reducing the volume of the Cantareira reservoir system down to just 5% of capacity.
“Studies more than 20 years ago predicted what is happening with lowering rainfall. Amazon deforestation is altering climate. It is no longer about models. It is about observation,” warned Nobre. “The connection with the event in São Paulo is important because finally people are paying attention.”
The NASA-led GEDI programme will not be completed until 2018, by which time it could be too late for the Amazon rainforest.
Nobre is hoping that the government will heed this interim warning and react by stopping deforestation and planting new trees, but under the current president’s regime, forest clearance has noticeably accelerated. Still, he has hope that his evidence along with international pressue will finally have a positive affect:
“They have taken good action in the past,” says Nobre. ““I hope they will listen now”.