15 - Climate and Climate Variability Flashcards
This deck focuses on the factors and processes that influence climate and climate zones, including latitude, atmospheric and ocean circulation, and natural climate drivers such as volcanic eruptions and Milankovitch cycles. It also delves into the evidence used to reconstruct past climate variability, including ice cores and sediment cores. (39 cards)
Define:
climate
The long-term average of weather patterns in a region.
Climate represents the sustained atmospheric conditions in a region over many years, rather than short-term variations.
Explain:
How does climate differ from weather?
- Climate is long-term weather patterns.
- Weather is short-term weather patterns.
Weather can change in minutes or days, but climate takes years to shift.
Define:
climate zone
Region classified by temperature, precipitation, and vegetation.
These zones help describe how climate varies across different regions of the Earth.
Explain:
What are the three major climate zones on Earth?
- Tropical
- Temperate
- Polar
Tropical: Warm, humid, near the equator.
Temperate: Moderate, distinct seasons.
Polar: Cold, ice-covered, near the poles.
Define:
climate variability
Natural fluctuations in climate over short and long periods.
Unlike climate change, which refers to long-term trends, climate variability includes short-term patterns like El Niño or volcanic cooling.
True or False:
The polar climate zone receives the most solar radiation.
False
The polar regions receive the least solar radiation, leading to extreme cold.
Identify:
What is the layer of the atmosphere where weather occurs?
troposphere
The troposphere is the lowest layer of the atmosphere, where most of Earth’s air mass and water vapor are found, driving weather patterns.
True or False:
Climate change only affects temperature.
False
It also affects precipitation, sea levels, and extreme weather events worldwide
Define:
latitude
A geographic coordinate that measures distance from the equator.
Latitude affects solar radiation intensity, influencing climate zones such as tropical, temperate, and polar regions.
Identify:
What cycle drives long-term climate change from orbital shifts?
Milankovitch Cycle
These changes affect how much solar energy Earth receives, leading to natural climate variations over thousands of years.
Explain:
What are the components of the Milankovitch Cycle?
- Eccentricity
- Axial Tilt
- Precession
Eccentricity: Changes in Earth’s orbit shape.
Axial Tilt: Variations in Earth’s tilt angle.
Precession: The wobbling motion of Earth’s axis.
Explain:
How does axial tilt influence climate?
Greater tilt increases seasonal contrasts.
A higher tilt angle leads to more extreme summers and winters, while a lower tilt reduces seasonal differences.
Identify:
What is eccentricity in Milankovitch cycles?
The change in Earth’s orbit from circular to elliptical.
This affects the amount of solar energy Earth receives, contributing to glacial and interglacial periods.
True or False:
Milankovitch cycles operate over short time periods.
False
These cycles take thousands to hundreds of thousands of years to complete, driving long-term climate change.
Describe:
How do Milankovitch cycles contribute to ice ages?
They regulate solar energy reaching Earth.
Periods of reduced solar energy lead to glacial expansion, while increased energy triggers ice melting.
Define:
atmospheric circulation
The movement of air across the planet that distributes heat.
Wind patterns such as Hadley, Ferrel, and Polar cells help regulate climate.
Explain:
Why is atmospheric circulation important for climate?
It redistributes heat and moisture, affecting regional climates.
Wind currents move warm air toward the poles and cold air toward the equator, shaping climate patterns.
Identify:
What drives the large-scale movement of seawater?
Ocean currents
Ocean currents regulate climate by transferring heat across the globe.
Define:
El Niño
A periodic warming of the central and eastern Pacific Ocean.
It disrupts global weather patterns, causing droughts, floods, and storms.
Explain:
How does El Niño impact global climate?
It alters precipitation and temperature patterns worldwide.
It weakens trade winds, leading to extreme weather events in many regions.
Explain:
What are the main natural climate drivers?
- Volcanic eruptions
- Solar radiation changes
- Milankovitch cycles
Volcanic eruptions – Release particles that block sunlight, causing cooling.
Solar radiation changes – Variations in the Sun’s energy that can warm or cool the Earth.
Milankovitch cycles – Long-term changes in Earth’s orbit that affect climate.
Identify:
What is the main climate effect of volcanic eruptions?
Short-term cooling
Volcanic eruptions release sulfur dioxide, forming aerosols that reflect sunlight and lower global temperatures.
Explain:
What was the climate impact of the 1815 Mount Tambora eruption?
It caused the Year Without a Summer.
Global temperatures dropped due to volcanic aerosols, leading to widespread crop failures and extreme weather.
True or False:
Asteroid impacts cause rapid cooling and ecosystem collapse.
True
Large asteroid impacts eject dust and aerosols into the atmosphere, blocking sunlight, lowering temperatures, and disrupting climate systems, leading to mass extinctions.
