The beauty and biological richness of the Amazon rainforest is priceless. It is possible, however, to put a price on its fisheries, carbon storage, and pharmaceuticals among other aspects. Estimates of the cost OF losing these over 30 years range from $957 billion to an eye-watering $3,589 billion. The cost to save it, meanwhile, is still beyond most people’s comprehension, but 8-50 times less than letting it go.
The world’s largest rainforest faces many threats and Brazil’s President-elect Jair Bolsonaro’s intention to open up even more areas to cattle ranching will make these far worse. A less immediate, but possibly worse threat is of a large-scale climate shift, where the rainforest is replaced by drought-prone savannah.
We know such a shift could be triggered by a combination of global warming and deforestation interfering with the basin’s phenomenal water cycle. What remains uncertain is how much of each of these forces would trigger such a shift, known as Amazonian forest dieback. A paper in Proceedings of the National Academy Of Sciences warns “Although a few arguments support the notion that such an Amazon dieback may be improbable, it is premature to rule it out.”
Were the dieback scenario to occur, it would not only destroy existing rainforest, and the phenomenal number of species it supports, but make future recovery almost impossible.
Costs of losing the rainforest include the sudden need to rehouse many people who draw their living from the area and the spread of transmissible diseases, among many others. The paper’s authors, led by Professor David Lapola of Brazil’s University of Campinas, consider how much it would cost to eliminate, or at least moderate, this risk.
The best mitigation strategy would be to sharply cut back on greenhouse gasses, the authors note. However, they acknowledge the cost of doing this is so large that saving the Amazon will be only a small factor in determining such global decisions.
Instead, Lapola and co-authors consider options that could be implemented locally. Some of these, such as the application of hundreds of millions of tonnes of fertilizer are likely to work, but have such severe negative effects the authors recommend against them.
However, a package of measures including deforestation prevention, restoring landscapes, and changing agricultural practices in nearby areas would collectively cost $27.5-$64.2 billion and decrease the dieback risk. A range of additional measures costing $122 billion would soften the blow if a climate shift still occurred, while providing benefits justifying their cost even if the danger is limited.
Finding such money will be difficult, particularly in the face of hostility from the Brazilian government. If only there was someone with a wealth of over a hundred billion dollars with a reason to feel attached to the Amazon.