Deforestation is a Killer

Just one of many.

Photo by Marco Haenssgen on Unsplash

Scientists now say that parts of the Amazon have turned from a carbon sink to a carbon emitter. The area in question only covers about 20 percent of the Amazon; but that 20 percent has lost 30 percent of its canopy since its peak. This could bring us closer to a tipping point where the whole Amazon becomes more of a carbon emitter, than a carbon sink. Not surprisingly, beef is to blame.

A dieback of the Amazon Rainforest may reach a tipping point soon, where the jungle cannot grow back and becomes savannah more than a jungle. Currently, the Amazon is one big positive feedback loop. Rain in the Amazon returns to the atmosphere through evaporation, trees also return water to the atmosphere through their leaves (transpiration). This process results in a moist atmosphere and the rising upward motion of air which ultimately brings more rain.

Making the forest smaller, which we have been doing through logging and cutting away the forest to make farmland, slows down this pattern. At some point, the Amazon may become too dry to come back as a jungle on any kind of human timescale, instead turning into savannah which would mean less evaporation and transpiration in the atmosphere, which leads to a drying of the environment, which leads to a loss of jungle, and so on. Not only does the Amazon bring rain to South America, but it is also responsible for some of the oxygen we breathe. No big deal.

If you were reading what I wrote over the past week or two, you may remember that the plankton and algae in the ocean provide about half of the oxygen we breathe, and are in danger as well. If we lose more than half of the oxygen we breathe, we won’t all die, but survival of the fittest will weed out most of us on an earlier timescale than normal. To put things in perspective, the summit of Mount Everest has about 33% less oxygen than you are used to. The city of Denver is about a mile above sea level and has about 17% less oxygen than land at sea level. Your body can adjust up to a point. But let’s not mess with massive oxygen depletion in the atmosphere, please. Animal life and human life would be devastated.

If we lose much of our rainforests and much of the ocean plankton, we are looking at a world with vastly decreased oxygen levels, a world where walking to the mailbox will feel like climbing Mount Everest.

But less oxygen is just one problem when losing the rainforest. Increased heat, degreased rain, biodiversity loss, less flood protection, and land degradation are just a few of the deleterious effects of rainforest loss.

Are we reforesting fast enough? No.

Since the end of the last ice age, the world has lost one-third of its forests. This land has been used for crops, livestock, fuel, and to make way for human development – from housing to golf courses.  Since those first civilizations about 10,000 years ago, we have been deforesting, but the pace of deforestation intensified since the Industrial Revolution. Half of the total forests we have lost happened in the last century.

In the chart from our friends at Our World in Data, we can see the decades of losses and gains in global forest cover. On the horizontal axis is time, from 1700 to 2020. The vertical axis is a change in forest cover. The taller the bar, the larger the change in forest area.

Reforestation is good, but not everything.

Forests only absorb about 10 -15 percent of global CO2 emissions. So even if we magically restored that 1/3 of forests that we cut down, and that magic happened tomorrow – forests would still only absorb about 20 – 25 percent of global CO2 emissions.

So yes, plant those trees, and tell your government to rewild, reforest, afforest (establishing new forests on land that wasn’t forest before), and all manners of building forests. But building back our forests is just one small piece of the puzzle.

Some countries have already turned the corner and referred the trend of deforestation.

But these places are the exceptions, not the rule yet.

Deforestation rates falling, but not fast enough.

Despite this progress, deforestation is still too high, and the pace of change is too slow.

Most of the deforestation in the world occurs in tropical forests, and much of this deforestation is driven by consumers in the developed world with tastes for beef, palm oil, cocoa, coffee, and other commodities produced on deforested land.  If there was less demand from the Global North, there would be less deforestation in the Global South. This demand isn’t the only issue. But it is the one most people reading this have some control over.

Such a change won’t happen overnight, but it can happen. More local food production, a reduction in the consumption of beef, effective conservation, lawmakers, companies, and investors putting forest conservation high on the agenda, can all help us get there.

As can degrowth.

You knew that was coming.

But I’ll save that discussion for next time.