Tropical forests are no longer a carbon sink-Now emits more carbon than all the vehicles in the U.S.

Climate change is really, really, really bad and we need to face the obvious fact that this is not going to end well for us. Humans need to pull it together, and work with each other to mitigate this looming catastrophic disaster that no sane person would ever want to face.

We are part of the biosphere’s web of life which sustains us, and every other creature on earth. The challenges we face today are many including food production, the unsustainable numbers of our population, either too much rain or too little, the decimation of our fellow species, depletion of the aquifers, epidemic diseases, the warming and acidification of the planet’s oceans and the changing climate. Humanity has had it easy since the last interglacial ice age 11,000 years ago due to our climate being surprisingly stable considering the ebb and flow of the great ice sheets (NASA).  This stability has allowed us to build the civilization that we enjoy today, we can farm and raise livestock because rainfall is generally predictable. But now we find ourselves at the most dangerous moment modern humans have ever faced.

Like “rats inside the experiment,” Neils Bohr Institute glaciology professor Jorgen Peder Steffensen says of us humans when he considers the risks of a sudden reconfiguration of global circulation which could, among other things, cause long-term drying across America’s breadbasket states.

“That’s going to impact the entire world,” Steffensen cautions in recognizing that the 11,000 years of the interglacial period since the last ice age “has been unreasonably stable. And we don’t know why” or how long that stability may persist.

Researchers from the Woods Hole Research Center and Boston University published a new study and Cosmos reported on yet another tipping point that we have crossed.

The world’s tropical forests are often described as the planet’s lungs; but now, due to human activity those lungs are emphysemic, with new research indicating they are no longer the globe’s great carbon sink. Instead, the rate of forest destruction, degradation and disturbance means they are emitting more carbon than they capture.

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Importantly, the analysis shows the clear dangers of deforestation – long recognised by the public and policymakers – are now overshadowed by the more subtle consequences of forests being degraded and disturbed. According to their calculations, degradation and disturbance account for 69% of total carbon losses from the world’s tropical forests.

“It can be a challenge to map the forests that have been completely lost,” says one of the paper’s authors, Wayne Walker, a scientist with WHRC. “It’s even more difficult to measure small and more subtle losses of forest. In many cases throughout the tropics you have selective logging, or smallholder farmers removing individual trees for fuel wood. These losses can be relatively small in any one place, but added up across large areas they become considerable.”

By providing a far more accurate picture of the state of tropical forests and their stunted role in the global carbon cycle, the findings are significant, striking and credible, says Pep Canadell, a climate scientist with Australia’s CSIRO and executive director of the Global Carbon Project.

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The conclusion that tropical forests are now emitting carbon rather than removing it from the atmosphere is due to the carbon in the forest biomass lost being greater than the carbon that can be absorbed by the remaining forest.

The paper notes that removed biomass may not necessarily be immediately released back into the atmosphere, as would occur if a tree was burnt. “Above-ground biomass may first transition to other carbon pools or be removed from the forest without release to the atmosphere.” But temporary carbon storage via the use of a tree trunk for wood products such as furniture and construction materials, they calculate, constitutes just 4-14% of losses.

Bottom line: a tree lost in a forest stops being a carbon absorber and, sooner or later, ends up emitting its stored carbon, either quickly through incineration or slowly through decomposition.