Today brings yet another devastating report from the UN’s Intergovernmental Panel on Climate Change, this time outlining how humanity’s exploitation of land is contributing to climate change. The big takeaway: Cutting out fossil fuels, which the United Nations panel has called for repeatedly, isn’t enough. We as a species need to fundamentally transform our relationship with the land to stand any hope of fighting climate change.
“There are still people talking about, 'OK, well let's reduce our emissions quickly and then we'll be fine,'” says Janos Pasztor, executive director of the Carnegie Climate Governance Initiative, who wasn’t involved in the report. “We won't be fine. It's not enough.”
It’s not enough because cutting emissions doesn’t fix the broken systems that underlie it. This new report takes steps to quantify how our abuse of the land—deforestation, industrial agriculture, draining of carbon-capturing peatlands—is driving climate change, and in turn how that climate change is exacerbating the degradation of land the world over. It’s a vicious circle the human species has to break, and fast.
Take our unhealthy relationship with meat. Demand has skyrocketed in recent decades, in part because booming economies are bringing the poor into the middle class. That demand causes more land to be cleared for livestock, leading to deforestation. Fewer trees means less carbon gets sucked out of the atmosphere. The food supply chain also brings emissions, and the animals themselves emit the extremely potent greenhouse gas methane.
Crop production is problematic too. Nitrogen-based fertilizers—which have massively boosted crop yields over the past few decades—come with serious costs. Excessive use means nitrogen is running into rivers and lakes and oceans, leading to algae blooms that kill fish and block sunlight from reaching aquatic plants—another blow to carbon sequestration. On land, an excess of nitrogen is good for the crops that can metabolize it easily, but the majority of species can’t handle it. Native plants die out and biodiversity suffers, leading to a homogenous landscape. This, in turn, makes the landscape less able to sequester carbon, sacrificing yet another way to mitigate climate change.
The emissions that come from industrialized agriculture—tending the stuff with machinery, packaging it, and shipping it to consumers—are driving more warming that in turn threatens that agriculture. Extreme heat withers crops, fiercer rainstorms degrade fields, and rising seas erode farmland. Soil erosion from agricultural fields may be 100 times higher than the rate at which soil forms. (To help stop that, the report suggests techniques like encouraging the growth of cover crops, which help buffer the soil from those fiercer rainstorms.) Overall, food systems are becoming increasingly insecure.
The problem isn’t just with food. Climate change is altering the nature of land itself. As the planet warms, weather patterns change, and lakes and rivers dry up as desertification takes hold. This, the report warns, kicks off yet another feedback loop: Dry soils strengthen heat waves. Not helping matters is urbanization and the heat island effect—cities absorb solar energy throughout the day and slowly release it at night, leading to warmer evenings. Combined with more intense heat waves, like the one that hit Europe this summer, these higher urban temperatures threaten public health, particularly for the young and elderly. The heat island effect can also intensify extreme rain events, both over a city and in regions downwind.
On top of that, water insecurity presents a looming catastrophe on lands across the world, both for people and plants. Plants that dehydrate to death can’t help sequester carbon, so the report warns we need to get smarter about sustainable irrigation. And rainfall patterns are changing, often in surprising ways, which spells trouble for communities. In Southern California, for instance, models predict that climate change will bring fewer, yet more intense storms. So Los Angeles is preparing itself by building a rain catchment network to store those deluges underground for times of want.
Less developed communities around the world, however, won’t be so lucky. “Extended droughts have led to local collapses of populations, including collapses of major civilizations,” says Michael Kiparsky, director of Wheeler Water Institute at UC Berkeley, who wasn’t involved in the report. “So this isn't something that is just doom and gloom—it has happened in the past.” In today’s global economy, climate refugees might find outside help in the form of aid. But large-scale migrations can also trigger conflict. “The world is a crowded place,” Kiparsky adds. “Places with available land and water have by and large been settled. Rather quickly, climate disruption leads to social disruption.”