12.1 covered the drivers of change. Today we map the three big changes to Earth's land surface — and how the world is responding.
By the end you can:
Each clusters by climate zone:
All three are driven or accelerated by people, and all three feed back into the climate — so they're studied together as one focus area.
Forests are cleared for cattle, soy, palm oil, logging, mining and roads, and the rate has accelerated in the tropics. The scale is tracked live by Global Forest Watch and audited every five years in the FAO Forest Resources Assessment.
Roughly 17–20% of the Amazon has been cleared, mainly for cattle pasture and soy, plus logging, mining and roads. It is a vast carbon store and holds enormous biodiversity.
Scientists warn of a dieback tipping point: if too much is cleared, parts of the rainforest could dry out and flip permanently to savanna — releasing its stored carbon and worsening global warming. You can watch the clearing fronts advance in near real time on Global Forest Watch.
Why is losing the Amazon a global problem, not just a Brazilian one?
Before we turn to the global response, watch this short explainer from National Geographic. It ties the whole causal chain together — why forests are cleared, what is lost, and how that loss feeds back into the climate. Treat it as a model of how to link cause to consequence in a single paragraph, and pair it with the live data on Global Forest Watch.
▶▶ Watch: Climate 101: Deforestation — National Geographic (click → opens on YouTube)As you watch, note: (1) the main drivers of clearing named; (2) two consequences — one for biodiversity, one for carbon; (3) one solution the film puts forward.
Land cover change is a global problem, so the response is international. At the UN Biodiversity Conference in Montreal, December 2022, roughly 196 governments (parties to the UN Convention on Biological Diversity) adopted the Kunming–Montreal Global Biodiversity Framework — a package of 23 targets.
Its flagship target — “30×30” — is to protect 30% of the planet's land and oceans by 2030. It also commits nations to restore degraded ecosystems, cut harmful subsidies, and respect Indigenous rights. Australia is a party and has adopted the 30×30 goal.
It affects over 100 countries: clearing/overgrazing plus drought strip vegetation → soil erodes → fertility falls → more pressure on what's left.
The Sahel faces desertification from a mix of drought, overgrazing, fuel-wood collection and rapid population growth. As vegetation is stripped, soils erode and lose fertility, forcing communities onto ever-poorer land.
The impacts are severe: falling crop yields, food and water insecurity, and displacement. The main response is the Great Green Wall — an ambitious pan-African effort to restore a band of vegetation right across the continent, planned as an 8,000 km belt aiming to restore 100 million hectares of degraded land by 2030.
Ice is both a freshwater store and a driver of sea-level rise — so its loss hits water supply and coasts.
Polar and mountain regions are remote and vast, so measuring ice change on the ground is impractical. Instead, scientists use satellite imagery and remote sensing to track glaciers consistently over wide areas and long periods.
Studies of Greenland's marine-terminating glaciers map exactly where ice is being lost fastest. This data feeds directly into sea-level-rise projections and government policy — a live example of spatial technologies as a geographical tool.
Taken together, deforestation, desertification and ice loss are so widespread that many scientists argue human activity is now a planetary geological force — comparable to the natural processes that shaped past epochs.
This raises a big question for geographers: if every environment now bears a human fingerprint, can any system still be studied as if it were “natural”?
“There is no longer such a thing as a purely natural system.” Argue for and against.
Every claim in this lesson traces back to a primary source — a monitoring platform, a global assessment or an official agreement. Use these to check the data yourself and to build a research task. Being able to name and cite a source is exactly what lifts a Band 5–6 response above a Band 3–4 one.