The great dependence of some countries producing oil, coal and gas for domestic consumption and / or exports, which could lead to non-compliance with the agreements.
The exploration and discovery increases of large hydrocarbon deposits, which do not seem to stop, will increase the production of oil, coal and natural gas.
The implementation of fracking or hydraulic fracturing, an unconventional technology used to release hydrocarbons embedded in rocks of very low porosity, in great depths that can exceed three kilometers.
That important unanticipated amounts of carbon are released into the atmosphere, from permafrost deposits, in frozen places, although without ice, due to the effects of global warming itself.
That significant unanticipated amounts of carbon are released into the atmosphere from peat bogs due to the felling and burning of forests
That the entire Green Fund, 100 billion dollars per year, starting in 2020, should not be combined to help low-income countries meet their national goals of the Paris Agreement.
The inability to effectively control the commitments acquired by each country.
Corruption in many countries could divert resources from the Green Fund to different destinations for which they were created.
The obstacle of the deniers of global warming and climate change, which could fail the climate agreements reached in Paris, in 2015.
That one or several countries, large polluters, withdraw from the Paris Agreement.
A global economic crisis that diverts the attention and resources necessary to meet climate goals.
A great war that distracts governments from the fight against climate change.