Geography yr 9 t2

• A biome is a distinct geographical region with specific climate, vegetation, and animal life.
• Latitude affects: As you move away from the equator to the mid and higher latitudes, the curvature of the Earth makes the Sun’s rays travel through more atmosphere, creating lower levels of insolation in any specific place, as the energy spreads over a larger area. As a result the energy from the Sun does not heat up the Earth as effectively, and the closer to the poles you travel the cooler it becomes
• Altitude also plays a significant role in determining climate. Temperatures fall by 0.65 °C for every 100 metres increase in

  elevation.
• Landforms: They (mountains) prevent the moisture-laden prevailing winds from reaching inland areas by creating a barrier. Rain falls on the windward side of a mountain and rain shadows form on the leeward side of mountains. Desert biomes often form in rain shadows.
• When cold ocean currents flow close to a warm land mass, a desert is more likely to form. This is because cold ocean currents cool the air above, causing less evaporation and making the air drier. As this dry air moves over the warm land it heats up, making it less likely to release

  any moisture it holds and so making areas it reaches arid.
• Geology: Some rocks and soils are more permeable than others, meaning they absorb the most moisture. Impermeable rocks result in higher rates of run-off.
• Soil: Plants need soil filled with nutrients to gain adequate food for survival. In cold climates, decomposition occurs slowly, meaning there isn't much nutrients in the soil. In hot, rainy climates, decomposition is also bad because the nutrients decompose so quickly there is little organic matter in the soil. Also, high rates of rain means the decaying leaches out of the soil.
• Overuse of land for agriculture or mining can lead to soil degradation, including erosion and loss of nutrients, which can have long-term impacts on the fertility of the soil.
• Land clearing and drainage causes erosion and deforestation. Roads can divide biomes and cut off essantial parts of ecosystems. This could mean that animals are cut off from food sources. Large scale farming profits often go to large companies and not to the local community.
• Sustainability refers to the ability to maintain or support a process continuously over time. In business and policy contexts, sustainability seeks to prevent the depletion of natural or physical resources, so that they will remain available for the long term.
• Isobars are areas of equal or constant atmospheric pressure. They indicate airflow and are measured in hectopascals (hPa)
• Winds are strongest when isobars are closer together
• >1013 is high pressure (sinking air often called anticyclones), =1013 is average air pressure, <1013 is low pressure (rising air).
• 'H' means clear skies and little wind
• 'L' means rain, clouds, and high winds
• Fronts represent the boundary between two air masses.
• A cold front is where cold air pushes underneath a warm air mass, making clouds, rain, and wind.

  
• Stationary fronts are the boundary between two air masses. They bring cloudy weather and light rain.
• Warm fronts move slower than cold fronts because it is harder for warm air to push against cold, denser air. They bring stormy weather. After the front passes, temperatures are warm.

  
• Occluded fronts are when warm air gets caught between two cold air masses. They bring quite stormy weather and can make weather colder.

  
• Agriculture concerns raising crops, and feeding, breeding, and raising livestock. Positives include the gaining of food and negatives include removal of native species and deterioration of soil and water.
• Irrigation is redirecting water for a specific purpose. They can help bring water to crops, useful during drought, but can increase groundwater level and decrease fishing and shipping opportunities (therefore impacting the rest of the food chain)
• Land terracing is growing crops on the sides of hills by planting on graduated terraces built into the slope. It maximises arable land in terrains (reducing soil erosion as there is no run off) but is very labour intensive
• Mining is the extraction of minerals and metals below the ground. However, mining can cause deforestation and reduce the amount of water in the soil
• the windward side receives more rainfall than the leeward side because when warm air meets a mountain, it is forced to rise. As it cools down, the moisture it carries falls .