Ecological land grab: food vs fuel vs forests.

By Agence France-Presse

The overlapping crises of climate change, mass species extinction, and an unsustainable global food system are on a collision course towards what might best be called an ecological land grab.

Coping with each of these problems will require a different way of using of Earth's lands, and as experts crunch the numbers it is becoming unnervingly clear that there may not be enough terra firma to go around.

A world of narrowing options threatens to pit biofuels, forests and food production against each other.

Experts who once touted "win-win" scenarios for the environment now talk about "trade-offs".

This looming clash is front-and-center in the most comprehensive scientific assessment ever compiled of how global warming and land use interact, to be released by the UN's Intergovernmental Panel on Climate Change (IPCC) on Thursday

Proposals to convert areas the size of India and the United States to biofuel crops or CO2-absorbing trees, for example, "could compromise sustainable development with increased risks -- and potentially irreversible consequences -- for food security, desertification and land degradation," a draft summary of the 1,000-page report warns.

Meanwhile, the fundamental drivers of Earth's environmental meltdown -- CO2 and methane emissions, nitrogen and plastics pollution, human population, unbridled consumption -- continue to expand at record rates, further reducing our margin for maneuver.

Case in point: to have at least a 50/50 chance of capping global warming at 1.5 degrees Celsius (2.7 Fahrenheit) -- the temperature guardrail laid down in a landmark IPCC report last year -- civilization must be "carbon neutral" within three decades.

Earth's surface temperature has already risen one degree Celsius above pre-industrial levels, enough to trigger deadly extreme weather and sea-level rise that could swamp coastal megacities by 2100.

And yet, 2018 saw a record 41.5 billion tonnes of planet-warming CO2 added to the atmosphere, up two percent from the previous record, set the year before.

Harsh reality

At this pace, humanity will exhaust its "carbon budget" for a 1.5 C world before US congresswoman Alexandria Ocasio-Cortez, co-sponsor of the Green New Deal, turns 45 (in 16 years).

Slashing carbon pollution remains the surest way to curb climate change, but -- absent a sustained crash of the global economy -- that can no longer happen quickly enough to singlehandedly keep global warming in check.

This harsh...