Savanna in AP Environmental Science

In AP Environmental Science, the savanna is a tropical and subtropical biome dominated by grasses with scattered drought-resistant trees, shaped by a climate with distinct wet and dry seasons and frequent fire.

Verified for the 2027 AP Environmental Science examLast updated June 2026

What is the savanna?

The savanna is one of the nine major terrestrial biomes you need to know for AP Enviro (EK ERT-1.B.2). Picture a wide grassland with a few trees sprinkled across it, like the African plains. That scattered-tree-over-grass look is the giveaway.

The reason it looks that way comes down to climate. Savannas sit in tropical and subtropical zones with a strong wet season and a strong dry season. There's enough rain to grow grasses, but the long dry stretch (plus frequent fires) keeps a full forest from taking over. Per EK ERT-1.B.1, the plants and animals here are adapted to exactly that climate: grasses bounce back after fire, and the trees are drought-resistant. Fire isn't an accident in a savanna; it's a regular part of how the ecosystem maintains itself.

Why the savanna matters in AP® Environmental Science

Savanna lives in Unit 1: The Living World, specifically Topic 1.2 Terrestrial Biomes. It supports learning objective AP Enviro 1.2.A, which asks you to describe the global distribution and environmental traits of each biome. The key idea threaded through the whole topic (EK ERT-1.B.3) is that biome distribution depends on climate, latitude, geography, soil, and nutrients. Savanna is a clean example: its wet-dry seasonal rainfall pattern is what defines it. Nail this and you've got a template for reasoning about every other biome on the exam.

How the savanna connects across the course

Temperate grassland (Unit 1)

Both are grass-dominated, but savanna is tropical with scattered trees and a wet-dry cycle, while temperate grassland sits in cooler mid-latitudes with almost no trees. Same vibe, different latitude and temperature.

Desert (Unit 1)

Push a savanna's dry season longer and rainfall lower and you slide toward desert. The Sahara was a green savanna roughly 10,000 years ago before climate shifts dried it out, which shows how thin the line between these biomes can be.

Global climate change and biome shifts (Units 1 and 9)

Because each biome is locked to a climate band, warming and changing rainfall can push savanna boundaries around. A region's wet-dry balance can tip it toward grassland, desert, or forest, which is exactly the kind of shift the exam loves to test.

Is the savanna on the AP® Environmental Science exam?

On multiple choice, savanna shows up as a description you have to identify: a region with distinct wet and dry seasons, scattered drought-resistant trees, and grasses is the classic savanna fingerprint. Questions also test the fire regime, since human activities that suppress or add fire change how the biome works. Expect comparison stems too, like which biomes in different hemispheres face similar climate-change challenges, or which biome shifts as the climate warms. The 2025 FRQ on Pacific sea surface conditions shows how Unit 1 climate-distribution thinking connects to bigger systems, so be ready to link a biome's traits back to its climate drivers, not just memorize a label.

The savanna vs temperate grassland

Both are grass-dominated biomes, which trips people up. The difference is climate: savanna is tropical/subtropical with warm temperatures, a sharp wet-dry season split, and a few scattered trees. Temperate grassland is in cooler mid-latitudes, has hot summers and cold winters, and basically no trees. If you see scattered drought-resistant trees, it's savanna.

Key things to remember about the savanna

  • Savanna is a tropical/subtropical biome defined by grasses, scattered drought-resistant trees, and a distinct wet-dry seasonal rainfall pattern.

  • Frequent fire is a normal part of the savanna; it keeps grasses dominant and prevents a full forest from taking over.

  • The biome's plants and animals are adapted to its climate, which is the core idea behind EK ERT-1.B.1 and objective AP Enviro 1.2.A.

  • A longer dry season and less rain push savanna toward desert, which is why the Sahara was once a green savanna.

  • Don't confuse savanna with temperate grassland; savanna is tropical with scattered trees, temperate grassland is cooler with none.

Frequently asked questions about the savanna

What is a savanna in AP Environmental Science?

It's a tropical and subtropical terrestrial biome dominated by grasses with scattered drought-resistant trees, shaped by a climate with strong wet and dry seasons. It's one of the nine major biomes listed in EK ERT-1.B.2.

Is savanna the same as grassland on the AP exam?

No. Savanna is tropical, warm year-round, and has scattered trees, while temperate grassland is in cooler mid-latitudes and has essentially no trees. The presence of scattered drought-resistant trees plus a tropical wet-dry climate is what marks a savanna.

Why is fire so important in a savanna?

Fire is a natural part of the savanna's cycle. It clears out woody growth and lets the grasses, which recover quickly, stay dominant. Human activities that change the fire regime, like fire suppression or overgrazing, can shift the whole ecosystem.

How can the Sahara have once been a savanna?

Around 10,000 years ago the region had more rainfall and supported lakes and diverse vegetation in a savanna ecosystem. Long-term shifts in climate and rainfall patterns dried it out, which shows how closely a biome is tied to its climate.

How does climate change affect the savanna?

Because savanna is locked to a specific wet-dry climate band, changes in temperature and rainfall can push its boundaries, tipping regions toward desert, grassland, or forest. This ties Unit 1 biomes directly to the climate-change material later in the course.