The devastation extends worldwide. The great euphorbia trees of southern Africa are succumbing to heat and water stress. So are the Atlas cedars of northern Algeria. Fires fed by hot, dry weather are killing enormous stretches of Siberian forest. Eucalyptus trees are succumbing on a large scale to a heat blast in Australia, and the Amazon recently suffered two “once a century” droughts just five years apart, killing many large trees.

Experts are scrambling to understand the situation, and to predict how serious it may become.

Scientists say the future habitability of the Earth might well depend on the answer. For, while a majority of the world’s people now live in cities, they depend more than ever on forests, in a way that few of them understand.

The situation with the planet’s forests makes it more important than ever that the world’s governments come together to finally agree to a deal to protect forests, which absorb as much as 25 percent of our carbon emissions. On the table is a UN framework called Reduced Emissions from Deforestation and Forest Degradation, known as REDD. The system would create a mechanism for rich countries to pay poorer forested countries such as Indonesia to protect their forests. Right now, they have an incentive to destroy forests to sell the timber and to make room for commodities like soy and cattle.

Governments have stumbled over the specifics of REDD for years, but they will yet another chance to strike a deal in November at the Durban climate talks. Let’s hope the negotiators read Gillis’ story and realize that we don’t have a minute to waste.