Kelly Levin and Sarah Parsons
Published 4 years ago.
About a 5 minute read.
Image: Alois Wonaschuetz/Pixabay
The Intergovernmental Panel on Climate Change's new report highlights the critical importance of land — both as a source of greenhouse gas emissions and as a climate change solution.
Most discussions of climate action focus on energy, industry and
transport. But a special report
released today by the Intergovernmental Panel on Climate Change
(IPCC) states unequivocally that land is critically important, as well —
both as a source of greenhouse gas emissions (GHGs) and as a climate change
In fact, the report found that while land sequesters almost a third of all
human-caused carbon dioxide emissions, it will be impossible to limit
temperature rise to safe levels without fundamentally altering the way the world
produces food and manages land.
Here are a few of the main takeaways:
About 23 percent of global human-caused GHGs come from agriculture,
forestry and other land uses. Land use
such as clearing forest to make way for farms, drives these emissions.
Additionally, 44 percent of recent human-driven methane — a potent greenhouse
gas — came from agriculture, peatland destruction and other land-based sources.
other land use changes, the world’s lands are removing more emissions than they
emit. Land removed a net 6 gigatonnes (Gt) of CO2 per year from 2007 to 2016,
equivalent to the annual GHGs produced by the United States. Further
deforestation and land degradation, though, will chip away at this carbon sink.
Scientists found that land temperatures increased 1.5˚C (2.7˚F) between
1850-1900 and 2006-2015, 75 percent more than the global average (which factors
in temperature changes over both land and ocean).
This warming has already had devastating impacts on the land, including
changes to rainfall and heat waves. Further impacts will impair land’s ability
to act as a carbon sink. For example, water stress could turn forests
into savanna-like states,
compromising their ability to sequester carbon — not to mention harming
ecosystem services and wildlife. The report warns that “the window of
opportunity, the period when significant change can be made, for limiting
climate change within tolerable boundaries is rapidly narrowing.”
The largest potential for reducing emissions from the land sector is from
and forest degradation, with a range of 0.4–5.8 GtCO2-eq per year. We’ll also
need large-scale changes to the way the world produces and consumes
including agricultural measures, shifting towards plant-based
and reducing food and agricultural waste.
In addition to reducing emissions, the land sector can also remove carbon
dioxide from the atmosphere. The report found that
have the greatest carbon-removal potential, followed by enhancing soil
and using bioenergy combined with carbon capture and storage (BECCS), a
process that uses biomass for energy and then captures and stores its carbon
before it is released back into the atmosphere. That being said, the authors
note that most estimates do not account for constraints such as land competition
and sustainability concerns, so these solutions’ actual carbon-removal potential
could be significantly lower than most models suggest.
The report found the following solutions to have the greatest co-benefits:
managing forests, reducing deforestation and degradation, increasing
organic carbon content in soil, enhancing mineral weathering (a process of
speeding up rocks’ decomposition to increase their carbon uptake), changing
and reducing food loss and
For example, increasing soil’s carbon storage can not only sequester emissions,
but also make crops more resilient to climate change, improve soil health and
increase crop yields.
For one, it will be important to consider the net carbon benefits of any
intervention — for example, planting forests on native grasslands could actually
lower the amount of carbon stored in soil, hampering an important carbon sink.
Some interventions may lower emissions, but cause other changes that ultimately
increase temperatures. For example, planting a dark evergreen forest at high
latitudes would lead to darker surfaces, especially during winter when snowpack
would be covered, thus increasing the absorption of solar radiation — much like
changing from a white shirt to a dark shirt on a sunny day. Planting certain
tree or plant species may threaten other species and ecosystems. And most
biological carbon sinks will eventually reach a saturation point where they
can’t absorb any more carbon. Also, future forest carbon uptake is not
guaranteed, since forest fires and pest outbreaks are likely to increase in a
Land-based emissions-reduction and carbon-removal efforts that require large
land areas — for example, planting large-scale forests and growing plants for
bioenergy — will compete with other land uses such as food production. This can
in turn increase food prices, worsen water pollution, harm biodiversity, and
lead to conversion of more forests to other land uses, thus further increasing
Furthermore, the report found that if the world fails to reduce emissions in
other sectors — such as energy and transport — we’ll need to rely ever more
heavily on land solutions, exacerbating food and environmental pressures.
Perhaps the most overarching insight from the IPCC report is that land use and
climate stability are a delicate balancing act: Getting it right can reduce
emissions while creating significant co-benefits; getting it wrong can fuel
climate change while worsening food insecurity and environmental problems.
WRI’s recent World Resources Report lays out 22
solutions to create more sustainable food and land systems. We can feed the
world while curbing climate change, protecting forests and growing economies —
we just can’t do it the way we’re doing things now.
Published Aug 8, 2019 1pm EDT / 10am PDT / 6pm BST / 7pm CEST
Kelly Levin is a senior associate with WRI’s global climate program.
Sarah Parsons is the Senior Editor for the World Resources Institute, where she works to expand the organization's Web presence.