Land use change

Land use change is a large and often overlooked source of greenhouse gas emissions. When land is cleared for crops, grazing, or urban development, habitats disappear and the carbon stored in soils and vegetation is released. Land use change accounts for around 11% of global greenhouse gas emissions, close to the footprint of global transport, and it is a major driver of biodiversity loss. Even so, both direct and indirect land-use change are still left out of many carbon footprints and life cycle assessments.

Land use change is the conversion of land from one use to another, for example turning forest into cropland, grassland into plantations, or farmland into housing. Direct land-use change can be observed and measured: when a forest is cleared for a palm oil plantation, the lost carbon can be linked straight to that plantation. These changes release stored carbon and reduce the land's future capacity to absorb CO2.

Indirect land-use change happens somewhere else because land is repurposed while overall demand for land stays the same. If existing cropland is switched to growing biofuel feedstock and demand for food does not fall, the shortfall is met by converting new land to agriculture or by intensifying production elsewhere. These market-driven effects can push cultivation into forests, wetlands, and peatland that hold high carbon stocks. Because indirect land-use change follows from market responses rather than a single visible event, its climate impacts are often missing from sustainability assessments.

Most activities involve land use, including some you would not expect. Plastics, for example, can still be tied to land-use change when the energy used in production and transport comes from biofuels grown on cropland or forest land. A footprint that leaves out direct and indirect land-use change understates real climate impact and can make some products look better than they are. Including land-use change is what makes a footprint complete and comparable.