Year 9 Geography: Climate Zones and Biomass Productivity Notes on Biomass Production

Definition of a Biome: A biome is a large area of Earth characterized by common features where plant and animal life have specifically adapted to that environment.
Terrestrial vs. Aquatic Biomes:
- Terrestrial: Refers to all biomes and ecosystems located on land.
- Aquatic: Refers to all biomes and ecosystems related to water.
The 11 Different Types of Biomes:
1. Polar
2. Tundra
3. Boreal
4. Mountain Vegetation
5. Temperate
6. Grasslands
7. Desert
8. Tropical Rainforest
9. Freshwater
10. Marine
11. Coral

Lines of Latitude: These are imaginary lines drawn on a map that run in an east-to-west direction. They are used to measure distances north or south of the Equator.
Biomass: The total weight of all living things within a specific area, including both plants and animals.
Climate: The typical weather patterns of a specific place, involving variables like temperature and rainfall, observed over many years.
Productivity: A measure of how much energy or food is produced by the plants and animals within a specific area.

Define: To clearly and precisely state the meaning of a specific word or concept in a simple way.
Explain: To show how or why something occurs by providing reasons, specific details, or examples.

Major Lines of Latitude (from North to South):
- Arctic Circle
- Tropic of Cancer
- Equator
- Tropic of Capricorn
- Antarctic Circle
Climate Zones (Arranged Spatially):
- Polar Zone: Located at the extreme North and South (the Arctic and Antarctic regions).
- Sub-Arctic / Sub-Antarctic Zones: Located just outside the polar circles.
- Temperate Zones: Located between the subtropical and sub-polar regions.
- Subtropical Zones: Located near the Tropics of Cancer and Capricorn.
- Tropical Zone (Torrid Zone): Located around the Equator, between the Tropic of Cancer and the Tropic of Capricorn.

Impact of Sun Position: The more direct sunlight an area receives consistently throughout the year, the hotter that area will be.
Tropical Zone Heat: This is the hottest part of the Earth because it receives the most direct sunlight due to its position relative to the sun.
Frigid/Polar Zone Cold: These areas are the coldest on Earth because they receive the least direct solar energy.
Temperate Zone Dynamics: The sun's position allows these areas to maintain moderate conditions, often described as "perfect holiday destinations" because they avoid the extremes of the tropical or polar zones.
Equinox: While used in the context of climate zones, this refers to the time or date (twice each year) at which the sun crosses the celestial equator, when day and night are of approximately equal length.

Beyond Facts: Explaining requires making a process clear so the reader understands why or how something works, rather than just listing facts.
Detailed Example (Climate and Deserts):
- Poor Answer: "The climate makes the deserts hot and dry."
- Effective Geographical Explanation: "Deserts have very little rainfall, which means the soil is very dry. Because of this, only certain types of plants, like cacti, can grow there. The hot temperatures also mean that animals need to be able to survive without much water."

Definition of Biomass: The total weight of all living things (or things that were once living) in a specific area. This includes tree trunks, branches, leaves, and animals, located both above and below the ground.
Measuring Large Scale Biomes: Because weighing an entire biome (like a desert or rainforest) is impossible, scientists use the following methods:
- Sampling: Scientists take samples from smaller, manageable areas and use that data to estimate the biomass of the entire biome.
- Carbon Dioxide Levels: Scientists look at carbon dioxide levels to determine productivity. This involves measuring how much $CO_2$ plants absorb during photosynthesis versus how much they release.
- Satellite Technology: Advanced instruments on satellites help scientists accurately measure carbon absorption and biomass levels from space.
Productivity Stats and Comparisons:
- Biomes are ranked from most productive (e.g., Tropical Rainforests) to least productive.
- Example measurement: Certain biomes produce approximately $800\,g$ of carbon per square metre per year ( $800\,g/\text{m}^2/\text{year}$ ).
- Productivity varies significantly between biomes; for instance, the productivity of grasslands must be distinguished from that of forests or deserts.

Borneo: A location used to study tropical biomes and high productivity levels.
- Alaska, USA: A location used to study sub-arctic/polar biomes and lower productivity levels.
- Tasmania, Australia: A location used to study temperate biomes.
Comparative Analysis: By comparing two locations (e.g., Borneo vs. Alaska), geographers can suggest reasons for differences in productivity, such as variations in climate, sunlight intensity, and rainfall.

Q: Explain why the tropical zone is the hottest part of the Earth.
- A: The tropical zone is the hottest because it receives direct sunlight throughout the year. The sun's position remains high in the sky relative to the Equator, maximizing solar radiation.
Q: Explain why the frigid zone is the coldest area on Earth.
- A: The frigid (polar) zones are the coldest because they receive the sun's rays at a very sharp angle, spreading the heat over a larger area and resulting in less intense warmth.
Q: How much productivity do grasslands produce?
- A: Grassland productivity is generally lower than tropical forests but higher than deserts, depending on the specific carbon measurements ( $g/\text{m}^2/\text{year}$ ) provided by regional data.
Q: Which biome produces approximately $800\,g$ of carbon per square metre per year?
- A: This specific level of productivity is typically associated with temperate forests or specific highly-productive grasslands/savannas, depending on the specific chart mapped in the lesson.