Atmospheric Circulation and Hummingbirds

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Questions and Answers

What causes temperature to drop at higher altitudes?

Decreased distance from the equator

Increased atmospheric pressure

Absence of sunlight

Constant decrease of 6° every 1000m increase (correct)

How do rain shadow effects create deserts?

Mountains block moisture from reaching the plains (correct)

Ocean currents supply excess moisture to the land

Rain clouds are always formed above mountains

High temperatures evaporate water in the mountains

What is a characteristic of maritime climate?

Complete isolation from ocean effects

Influence from wind crossing nearby ocean currents (correct)

Lack of precipitation throughout the year

Extreme temperature variations between day and night

What primarily drives the movement of ocean currents?

Rotational forces of the Earth and wind patterns Signup and view all the answers

Where do deserts commonly form based on atmospheric circulation?

At 30° N and S of the equator due to descending dry air Signup and view all the answers

What role do ocean currents play in coastal regions?

They moderate temperature and affect moisture conditions. Signup and view all the answers

What is a primary factor that affects the sea level difference between the equator and the poles?

Water density changes with temperature Signup and view all the answers

How does convergent evolution occur among organisms in specific biomes?

Similar environmental challenges lead to similar adaptations. Signup and view all the answers

What is the primary reason that hummingbirds enter a torpid state at night?

To conserve energy Signup and view all the answers

At what temperature does the West Indian Hummingbird lower its body temperature during torpor?

20°C Signup and view all the answers

Which of the following wind cells is responsible for low latitude overturning circulations?

Hadley cells Signup and view all the answers

How does the equator's temperature affect rainfall patterns?

Higher temperatures result in more moisture absorption Signup and view all the answers

What effect does adiabatic cooling have on air?

Reduces temperature without heat loss Signup and view all the answers

Which winds blow between the equator and the horse latitudes?

Trade winds Signup and view all the answers

What is the Coriolis Effect primarily caused by?

The Earth's rotation on its axis Signup and view all the answers

How does the presence of sea currents influence rainfall?

They affect local temperature variations Signup and view all the answers

What type of soil is typically found in the sandstone derived habitats?

Course grained and nutrient poor Signup and view all the answers

Which of the following plant types is most abundant in the fynbos region?

Protea-like shrubs Signup and view all the answers

How does fire benefit the fynbos ecosystem?

It allows for competitive advantages for seedling growth. Signup and view all the answers

Which animal behavior assists in the dispersal of seeds within the fynbos ecosystem?

Ants transporting seeds into their burrows Signup and view all the answers

What percentage of plant species in the region exhibits endemism?

68% Signup and view all the answers

What role do 'elaiosomes' play in the fynbos ecosystem?

They aid in seed dispersal by ants. Signup and view all the answers

What is a characteristic feature of shale/granite derived habitats compared to sandstone habitats?

Higher nutrient levels and good water retention Signup and view all the answers

Which of the following factors is NOT considered an abiotic factor affecting the fynbos ecosystem?

Soil nutrient levels Signup and view all the answers

What primarily distinguishes tropical rain forests from tropical deciduous forests?

Deciduous trees dropping leaves in winter Signup and view all the answers

Which factor contributes to the biodiversity found in tropical rain forests?

High temperatures throughout the year Signup and view all the answers

What is a characteristic feature of tropical montane forests?

Growth of epiphytes due to high humidity Signup and view all the answers

What role does dust play in savanna ecosystems?

Shift of biomes leading to extinction Signup and view all the answers

Which environment is characterized by an average rainfall of less than 25 cm yearly?

Deserts Signup and view all the answers

What distinguishes the tropical rain forests in Africa from those in South America?

Higher biodiversity among mammals Signup and view all the answers

Which species are essential for the survival of many other species in ecosystems like the tropical rain forests?

Keystone species such as fig trees Signup and view all the answers

What happens to grasses in savanna regions during the dry season?

They become dormant and die back Signup and view all the answers

What is a significant environmental factor affecting the Succulent Karoo biome?

Limited annual rainfall Signup and view all the answers

Which of the following characteristics is true for the Namakaroo Biome?

It has seasonal rainfall associated with migratory patterns Signup and view all the answers

Which plant strategy is typical in the Succulent Karoo biome?

Seeds require a rain droplet for dispersal Signup and view all the answers

What role does fire play in the Savanna biome?

It supports the balance between grasses and trees Signup and view all the answers

Which type of vegetation is predominantly found in the Grassland biome?

Grasses and geophytes Signup and view all the answers

During which season does the Savanna biome experience the highest rainfall?

Summer Signup and view all the answers

What impact does high altitude have in the Grassland biome?

Allows for a wide range of temperature fluctuations Signup and view all the answers

Which of the following biomes is the second largest in RSA?

Nama Karoo Biome Signup and view all the answers

Study Notes

Torpor in Hummingbirds

Hummingbirds enter a temporary dormant state called torpor to conserve energy when environmental temperatures drop.
This state reduces energy consumption by up to 80% as body temperature lowers from 40°C to 20°C.

Atmospheric Circulation Patterns

The troposphere is divided into regions of closed wind circulations by three distinct wind cells: Hadley cells, Ferrell cells, and polar cells.
Warm air from the equator descends around 30° latitude, where Hadley cells end, preventing warm air from reaching the poles.

Trade Winds

Easterly winds blowing between the equator and horse latitudes.
Blow from the northeast in the Northern Hemisphere and the southeast in the Southern Hemisphere.
Named "trade" in the 18th century due to their role in facilitating commerce across the Atlantic.

Hadley Cells

Low latitude overturning circulations with air rising at the equator and sinking at around 30° latitude.
Responsible for trade winds in the tropics and influencing low latitude weather patterns.
Solar radiation heats the equator, generating water vapor that rises into the atmosphere.
This cycle of hot and cold water results in adiabatic cooling, leading to precipitation.
The equator experiences high rainfall due to the release of water vapor as warm, moist air cools.

Coriolis Effect

The Earth's rotation causes deflection of air and wind, known as the Coriolis effect.

Variation in Rainfall

The Earth's surface is not uniform, with varying sea currents and temperatures.
Hot ocean currents flow from the equator to polar regions (vice versa for cold currents).

Latitude vs. Altitude

Mountains experience similar biomes as those at matching latitudes.
Temperature drops 6°C for every 1000m increase in altitude, equivalent to an 880km shift in latitude.

Coastal Regions: Rain Shadow Effect

Mountains affect weather patterns by blocking rain clouds and creating a dry environment on their leeward side.
Once precipitation forms, clouds can move over and cross mountains, becoming dry and removing moisture from the environment.

Factors Influencing Biomes

Deserts are often found at 30° N + S of the equator due to descending dry air masses.
Cold ocean currents along coastlines contribute to dry conditions next to continents.
High mountain ranges create rain shadow effects within the interiors of continents.

Coastal Regions

Ocean currents moderate temperatures along seacoasts, with breeze patterns shifting between land and sea throughout the day and night.
Continental climates are not moderated by distant oceans, while maritime climates are influenced by nearby ocean currents and winds.

Biomes

Climatically defined collections of organisms with a characteristic appearance and widespread distribution.
Similar types of organisms form communities within these biomes.
Convergent evolution occurs within biomes, resulting in organisms adapting to specific environments.

Ocean Currents

Water expands as it warms, creating a higher sea level at the equator compared to the poles.
This gravitational difference drives surface water movement.
Trade winds and temperature westerlies contribute to surface water flow.
Earth's rotation, landmass positions, and ocean basin shapes influence current direction and movement.
Warm currents flow away from the equator, pushed by trade winds.
Warm currents are faster and shallower compared to cold currents.

Climograph

Represents the relationship between precipitation and temperature, highlighting the distinction between different biomes and their unique weather patterns.

Tropical Rain Forests

Distributed equally around the equator, with high rainfall and humidity.
Home to half of terrestrial life.
Keystone species, such as fig trees, are crucial for the survival of other species within the rainforest ecosystem.

Types of Tropical Rain Forests

Tropical rain forests: annual rainfall exceeding 250cm, mean temperature above 25°C, humidity above 80%.
Tropical deciduous forests: occur in areas with winter droughts, leading to leaf drop.
Tropical montane forests/cloud forests: found at high altitudes in tropics, characterized by low temperatures, high humidity, and cloud cover.

Africa Tropical Rainforests

Drier than South American rainforests, with distinct ecological niches within the canopy.

Asia Tropical Rainforests

Mixture of emigrated species with increased precipitation.
Common epiphytes, including parasitic species, and flying animals adapted for gliding.

South America Neotropics Tropical Rainforests

Relatively new area with similar niches and fauna to other tropical rainforests.

Savannas

Located adjacent to tropical deciduous forests, characterized by grasslands with scattered trees.
Seasonal rainfall, with a long dry season.
Large herbivores and predators are prevalent.
Dust plays a role in expanding savanna biomes.

Deserts

Receive less than 25 cm of rainfall annually.
Hot deserts occur near 30° latitude due to descending dry air masses.
Nutrient-poor soils derived from sandstone and shale/granite are influenced by factors such as wind, fire, and rainfall patterns.

Deserts: Flowers

Exhibit unique adaptations to survive arid conditions, including:
- Protea-like shrubs with large, leathery leaves.
- Erica-like plants with fine leaves.
- Reed-like Restio plants providing shelter for animals.
- Bulbous plants with fire-stimulated flowering.

Deserts: Species

High vegetation diversity supports a large number of amphibian species.
Species richness increases with increasing surface area.

Deserts: Diversity and Endemism

Coverage: 90,000 km²
Plant species: 8,200
High endemism levels:
- 68% species
- 20% genera
- 6 endemic families

Deserts: Fire

Plants exhibit two fire survival strategies:
- Resprout: survive as adults and produce new growth from protected buds.
- Reseeders: rely on seeds to recolonize after fire.
Serotiny: seeds are retained in cones and released after fire, spread by wind.
Ants disperse seeds through myrmecochory, which involves elaiosomes (fatty substances on seeds attracting ants).

Renosterveld

Dominated by the daisy family.
Large diversity of grasses and animals.
Soil, fire, and wind dispersal influence its ecosystem.

Succulent Karoo Biome (Namaqualand)

Winter rainfall (20-290mm) with hot, dry summers.
Dominated by succulents, dwarf shrubs, and geophytes.
Endemic reptiles, low biomass, and no fires.
Similarities with fynbos due to winter rainfall and high species diversity.

Succulent Karoo Biome: Ecology

Unique desert flora with short lifespans and high turnover.
Plants are adapted to survive short periods of dehydration and frost.
Examples include stone plants and plants with spring-like mechanisms that release seeds after water droplet contact.

Nama Karoo Biome

Located on the central plateau in South Africa, with summer rainfall (100-520mm).
Second largest biome, with low rainfall and 18-year cycles associated with springbok migration.
Dominated by grasses and drought-resistant shrubs.
Semi-arid environment.

Savanna Biome

Covers 46% of South Africa, with complex delimiting environmental factors.
Summer rainfall (235-1000mm) and varying altitudes (2000m).
Grasses and scattered trees form a mosaic landscape.
Strong seasonality drives fire regimes and high biomass production.
Important for large herbivores and predators.

Grassland Biome

Found in high-lying areas of central South Africa.
Summer rainfall (450-1200mm), temperature fluctuations, and high altitudes.
Lack of trees due to frost, fire, and grazing pressure.
High biodiversity, with grasses and geophytes as dominant plant life.

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Description

Explore the fascinating phenomena of hummingbirds' torpor and the intricate patterns of atmospheric circulation. This quiz dives into how hummingbirds conserve energy and the roles of Hadley, Ferrell, and polar cells in our atmosphere. Test your knowledge on trade winds and how these systems affect global weather patterns.