If the Paris Agreement is to be honored, countries in the Global North must commit to fund conservation efforts in the Global South. That is the conclusion of Bard Harstad, a professor of environmental economics at the University of Oslo.

To stave off catastrophic global warming, Earth's inhabitants need to quickly reduce global carbon emissions. Doing so will require more than a reduction in the burning of fossil fuels. The planet's most valuable carbon sinks must also be preserved.

The problem, as Harstad's new paper in the Journal of Economic Theory detailed, is funding.

The South is generally only willing to conserve forest and guard against deforestation if they can expect payment from the North in the future. Meanwhile, countries in the North are often only willing to fork over cash when forests are directly threatened or already in the process of being cleared.

It's like a game of chicken with two losers and no winner.

"We've reached stalemate," Harstad said in a news release. "This fundamental contradiction means the market for conservation is not efficient and that a forest must be logged with some chance or gradually to secure the funding needed to protect it."

The reality is, the North stands to gain more from having the forests of the South conserved than the South would gain from clearing them. The problem is ensuring a fair and guaranteed transaction.

As Harstad explains, the North expresses a willingness to pay for conservation in the future as a way to encourage the South to protect and not clear forests. But when it the future arrives, the North may attempt to further delay payment.

Complicating matters further, some countries in the Global South are genuinely keen on conservation, which further incentivizes the North to withhold compensation.

Harstad thinks the solution is a binding treaty, guaranteeing future payments.

"For conservation to work, it is not important that the payment happens today, but the commitment to future compensation must be established already now," concluded Harstad.