2.4 Climate & Biomes (DP IB Environmental Systems & Societies (ESS): HL): Flashcards

Forest biomes can be divided into tropical rainforests, temperate forests and boreal forests.

The tropical rainforest biome contains approximately 50% of the world's plant and animal species.

Deserts are characterised by low rainfall and are dominated by plants such as cacti.

The main limiting factor for plant growth in the desert biome is water.

The tundra biome is found in regions with low temperatures and features a layer of permafrost.

False.

Tropical rainforest biomes, not grasslands, have the highest biodiversity of all biomes.

Permafrost is a permanently frozen layer of soil found in tundra biomes that limits plant growth and root penetration.

Savannas are a type of grassland biome found between 5° and 30° north and south of the equator.

The three main factors that determine biome distribution are insolation, precipitation and temperature.

Global warming can cause a biome type change by altering temperature and precipitation patterns, which may transform a biome such as a forest into a savanna or a tundra into a forest.

As global temperatures rise, biome boundaries shift poleward and upward in elevation.

False.

Cold biomes such as tundra and boreal forests are contracting as global warming causes warmer biomes to expand.

Range shifts are when species move to new areas seeking suitable conditions as their original habitats become less hospitable due to climate change.

The tricellular model of atmospheric circulation is a system of three large-scale cells (Hadley, Ferrel, Polar) in each hemisphere that circulate air and redistribute heat from the equator to the poles.

Wind formation is caused by air moving from areas of higher pressure to lower pressure, due to uneven heating of the Earth's surface by the Sun.

There are three types of atmospheric circulation cells: Hadley, Ferrel and Polar.

False.

The Polar cell is the smallest and weakest; the Hadley cell is the largest.

In the Hadley cell, trade winds blow from the tropics towards the equator and travel in an easterly direction.

Insolation is the amount of solar radiation that reaches the Earth's surface from the Sun.

The tricellular model influences the distribution of biomes by affecting patterns of precipitation and temperature across latitudes, which determine the type of biome that forms in each region.

Tropical rainforests are typically found within the Hadley cell, while polar deserts occur in the Polar cell.

Ocean currents are large-scale movements of water in the ocean, driven by winds and Earth's rotation, that redistribute heat around the globe.

Oceans act as heat reservoirs because they absorb solar radiation in their surface layers and store the resulting thermal energy.

Surface ocean currents transport warm water from the equator towards the poles, and cold water from the poles towards the equator.

False.

Ocean currents affect regional climates by distributing heat and influencing temperature and weather patterns in coastal areas.

Thermal energy in the context of oceans is the heat stored in ocean water after absorbing solar radiation.

Ocean currents affect marine ecosystems by influencing patterns of productivity, species distributions, and marine biodiversity.

A tropical climate is characterised by consistently high temperatures and high rainfall, typically found between the Tropics of Cancer and Capricorn.

The three general climate types are tropical, temperate, and polar.

Tropical climates are typically found between the Tropics of Cancer and Capricorn.

A savanna is a grassland biome scattered with trees, typically found in tropical regions with distinct wet and dry seasons.

Equatorial tropical climates have high temperatures and high humidity year-round, with consistent rainfall and little seasonal variation.

Seasonal tropical climates typically support savannas, which are grasslands scattered with trees.

A temperate climate has moderate temperatures with four distinct seasons, and can be influenced by oceans (maritime) or located inland (continental).

Maritime temperate climates have milder temperatures and more consistent rainfall due to the influence of large bodies of water, while continental temperate climates have greater temperature extremes and are found inland.

Temperate forests are supported in regions with consistent rainfall throughout the year and mild temperatures.

A polar climate is characterised by very low temperatures, limited precipitation (mainly snow), and extreme conditions found in Arctic and Antarctic regions.

True.

Tundra biomes, with short growing seasons and low, hardy vegetation, are characteristic of polar climates.

A key factor that can prevent the expected biome from developing in a climate zone is human intervention, such as urbanisation or agriculture.

Secondary influences such as soil quality, topography, fire, and natural disturbances can limit or alter the natural development of a biome, even if the climate is suitable.

The El Niño Southern Oscillation (ENSO) is a natural climate phenomenon characterised by fluctuations in wind patterns and sea surface temperatures across the tropical Pacific Ocean.

The two extreme phases of the ENSO cycle are El Niño (warming phase) and La Niña (cooling phase).

During normal conditions, trade winds blow in a westerly direction across the tropical Pacific.

False.

ENSO events are irregular and difficult to predict in terms of frequency and intensity. They usually occur every 2–7 years.

The process where cold, nutrient-rich water rises to the surface is called upwelling.

El Niño conditions occur when the east-to-west trade winds weaken or reverse, leading to warmer-than-usual sea surface temperatures in the central and eastern tropical Pacific.

El Niño leads to reduced upwelling and decreased marine productivity off the coast of South America.

El Niño can cause drier conditions in Australia and Southeast Asia, and heavy rainfall and flooding on the western coast of the Americas.

During La Niña, the Walker circulation strengthens, leading to increased upwelling in the eastern Pacific.

La Niña increases upwelling of cold, nutrient-rich water off South America, which increases marine productivity.

Coral bleaching is the process where coral reefs lose their colour and vital algae due to warmer sea temperatures, often linked to El Niño events.

Secondary impacts of ENSO events include food shortages due to crop damage and increased spread of diseases such as malaria.

A tropical cyclone is a large, rapidly rotating storm system that forms over warm tropical oceans, with a low-pressure centre (the 'eye'), strong winds, heavy rainfall, and thunderstorms.

Tropical cyclones form over warm ocean waters above 26.5 °C where there is sufficient evaporation and the Coriolis effect is strong enough to cause rotation.

The Coriolis effect is the deflection of moving air caused by the Earth's rotation, which causes tropical cyclones to rotate and develop a spiral structure.

A tropical cyclone is called a hurricane in the Atlantic, a typhoon in the Western Pacific, and a cyclone in the Indian Ocean.

The low-pressure centre is caused by rising warm, moist air that condenses, releases latent heat, and causes further uplift, reducing surface pressure.

In tropical cyclones, latent heat is the energy released when water vapour condenses into clouds and rain, warming the air and intensifying the storm.

The energy for tropical cyclones comes from the evaporation of warm ocean water and the release of latent heat.

Climate change leads to warmer oceans, which provide more energy for tropical cyclones, increasing their intensity with stronger winds and heavier rainfall.

A storm surge is an abnormal rise in sea level caused by strong winds and low pressure during a tropical cyclone, leading to coastal flooding.

Research indicates a 40% increase in the likelihood of storms reaching category 3 or above since the 1980s.

True.

Typhoon Haiyan had wind speeds exceeding 315 km/h and is an example of a very intense tropical cyclone, likely made stronger by warmer sea temperatures.

The energy for tropical cyclones comes from the evaporation of warm ocean water, which releases latent heat energy as water vapour rises, condenses, and fuels the storm.