Land Use Changed the Climate. Now Climate’s Changing the Land

Land-use change has long been recognized as a major contributor to global warming. Deforestation and agriculture alone account for nearly 25% of human-caused greenhouse gas (GHG) emissions.

One might think this effect is uni-directional: Cutting down trees, plowing up grasslands and draining wetlands release GHGs that fuel climate change. But satellite monitoring shows that this relationship is a two-way street. Climate change itself is increasingly leading to the loss and degradation of forests, grasslands, wetlands, rivers and even farms, creating a dangerous feedback loop.

Hotter, Drier Conditions Accelerate Forest Fires

Let’s look at wildfires. As the graphic below shows, large-scale fires burned more than twice as much forest over the past decade (2015-2024) than they did in the previous one (2001-2010). A warming climate is creating hotter, drier conditions for longer periods of time, escalating fire risk.

Fire accounted for one-third of land cover change globally in 2023. Boreal and humid tropical regions — home to the world’s last great tracts of natural forest — have experienced especially dramatic increases in forest loss due to fire. This trend is driven by a warming climate. Emissions from forest fires have increased 60% since 2001, largely due to more fires in boreal forests.

Droughts Kill Trees, Deplete Rivers

Meanwhile, climate change-induced droughts are destroying crops, killing trees and depleting river basins to record lows. Satellite images allow us to see the detailed impacts of drier conditions on the planet’s surface.

For example, southeastern Australia reached its driest month in at least 110 years in September 2023. “Flash droughts” like the one shown below, where unusually rapid drying occurs due to lack of precipitation and unusually high heat, are increasing. That’s a problem not only for water use, but for trees, crops and other vegetation.

The Amazon River also reached record-low levels in October 2023. The port city of Manaus experienced its lowest water levels in 121 years of measurement, limiting navigation and threatening wildlife. Fears of the Amazon crossing a tipping point — where climate change increases the intensity and length of dry periods so much that rainforests turn into savannas — may now be playing out, with fires and droughts driving the conversion. The image below shows the drop in water levels for the Rio Negro, located just above Manaus where it joins the main stem of the Amazon River.

Stronger Storms Are a Growing Threat to Nature and People

Finally, let’s look at storms. A warmer climate creates more energy, fueling storms that are stronger and longer-lived. These storms impact natural ecosystems as well as cities and farms through landslides, erosion, floods and “windthrow,” where strong winds knock down trees.

The satellite image below shows the impact of landslides caused by cyclone Freddy, the longest-lived cyclone on record. The 2023 storm caused more than 1,000 deaths, displaced more than 600,000 people, and destroyed nearly 200,000 hectares of farmland in Malawi. The country has historically experienced one cyclone every seven years; five have hit Malawi in the past seven years alone.

Acting on Climate and Nature Together

As world leaders come together this month in Belém, Brazil for the 30^th UN climate summit (COP 30), actions to curtail GHG emissions and conserve nature are more urgently needed — and more interconnected — than ever.

The world needs to double-down on advancing the energy transition to address the largest source of GHG emissions. This means adding more clean energy, electric vehicles, energy efficiency and smart city designs. The world also needs to stop ecosystem conversion and halt the dangerous nature-climate feedback loop. This means producing the food we need with less land and resources, reducing demand for land-intensive products like beef, protecting the nature that remains, and restoring what’s been lost.

The causality between climate change and land-use change goes both ways — so, too, do the solutions.