Dec. 17, 2019 12:35PM EST
The bushfires that have been
tearing through New South Wales and Queensland, decimating koala habitats, taxing the
water supply, and choking the air since August have claimed six lives. Now, new
NASA data shows that the fires have emitted 250 million tons of carbon dioxide,
the equivalent of half thee country's annual greenhouse gas emissions, according to The Guardian. In 2018, Australia's total greenhouse has
emissions was 532 million tons of carbon dioxide.
Dr. Niels Andela, a scientist
at the NASA's Goddard Space Flight Center and a collaborator in the Global Fire
Emissions Database, gave the data to The Guardian Australia.
Usually, bushfires are
considered carbon neutral, because when vegetation regrows it absorbs the
carbon dioxide the fires have emitted. However, scientists are predicting that
the scale of this year's fires coupled with drought-stricken forests will make
it impossible for the vegetation to absorb the carbon, as The Guardian reported.
"Drought-stressed trees
recover less well – carbohydrates reserves are exhausted – and under climate
change tree growth may be slow and fires more frequent, meaning less tree
biomass and even loss of forest cover," said David Bowman, a fire ecologist
at the University of Tasmania, to the Guardian. "This is a nasty negative feedback cycle
of a biosphere carbon sink becoming a source [of carbon]."
Pep Canadell, a senior
research scientist at the CSIRO Climate Science Centre, told the Australia Broadcasting Corporation (ABC) Australia's
forests had more in common with the Amazon than people would think.
"We're talking about very
different sizes, of course. [There] are more carbon-dense forests in Amazonia
than in Australia," said Canadell. "Having said that, a lot of [bush
areas] burning now in NSW are actually exceptionally carbon-dense — they're
very tall and quite dense forests. So from a per square meter or hectare level,
we're certainly not shy away from what is happening in the Amazon."
The bushfires have already
burned over 6.7 million acres of land and they could last through the
Australian summer, until March or longer, as Gizmodo reported.
The fires follow the pattern
of the Amazon fires and the California fires that create a carbon feedback
loop, where human activity compromises Earth's ability to absorb carbon as we
emit more of it, according to Gizmodo. These events are becoming more common as the Earth
warms. It's especially evident in melting permafrost, which releases a
tremendous amount of trapped carbon as it thaws, as the National Oceanic and
Atmospheric Administration's Arctic Report
Card found.
"This pulse of fire
emissions should indeed be of concern. Any additional carbon emissions to the
atmosphere, with no guarantee that it will be removed back by regrowing
vegetation in a later stage, is of concern, particularly in an Australia under climate
change," said Canadell, as The Guardian reported. He added, "Thus, it is
important to understand both risks – the emissions from fires but also the
potential long-term loss of CO2 sink capacity of the terrestrial vegetation due
to the incomplete recovery of burned landscapes due to permanent degradation.
These emissions are very significant."
"The nightmare scenario
is that because of climate change, the forest isn't able to recover
itself," said Bowman to ABC. "Once we actually know for certain what's
happening, it's going to be too late. And this is a big thing to be wrong
about."
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