global systems

Question 1

What are the four spheres outlined in Earth science?

Answer 1

Lithosphere - rocks and crust of the planet
Biosphere - ecosystems and living organisms
Atmosphere - gases surrounding the planet
Hydrosphere - all water in the earth

The lithosphere refers to the solid outer part of the Earth, the biosphere encompasses all living organisms, the atmosphere is the layer of gases surrounding the planet, and the hydrosphere includes all water bodies.

Question 2

Identify common greenhouse gases.

Answer 2

• Carbon dioxide (CO2)
• Methane (CH4)
• Nitrous oxide (N2O)
• Water vapor (H2O)

These gases trap heat in the atmosphere and contribute to the greenhouse effect.

Question 3

Describe the greenhouse effect.

Answer 3

The greenhouse effect is the process by which certain gases in the Earth’s atmosphere trap heat, preventing it from escaping back into space.

This natural process maintains the Earth’s temperature, making it suitable for life.

Question 4

What is the difference between the greenhouse effect and the enhanced (or anthropogenic) greenhouse effect?

Answer 4

The greenhouse effect is a natural process, while the enhanced greenhouse effect is caused by human activities increasing greenhouse gas concentrations.

Human activities such as burning fossil fuels and deforestation contribute to the enhanced greenhouse effect.

Question 5

How do changes to the carbon cycle impact the greenhouse effect?

Answer 5

Changes to the carbon cycle can increase the concentration of greenhouse gases in the atmosphere, intensifying the greenhouse effect.

For example, deforestation reduces carbon absorption, leading to higher CO2 levels.

Question 6

Describe how carbon dioxide has changed since the Industrial Revolution.

Answer 6

Carbon dioxide levels have significantly increased, rising from about 280 ppm to over 400 ppm.

This increase is primarily due to fossil fuel combustion and land use changes.

Question 7

Describe how methane has changed since the Industrial Revolution.

Answer 7

Methane levels have increased from approximately 700 ppb to over 1800 ppb.

This rise is largely due to agricultural practices, landfills, and fossil fuel extraction.

Question 8

What is the trend in global temperatures since the Industrial Revolution?

Answer 8

Global temperatures have risen by about 1.2 degrees Celsius.

This increase is attributed to human-induced greenhouse gas emissions.

Question 9

What is the trend in mean sea level since the Industrial Revolution?

Answer 9

Mean sea level has risen by approximately 20 cm.

This rise is influenced by thermal expansion of seawater and melting ice sheets and glaciers.

Question 10

Explain the changes to Arctic Sea Ice Minimum extent.

Answer 10

Arctic Sea Ice Minimum extent has decreased significantly, showing a decline of about 40% since the late 1970s.

This decline impacts global weather patterns and marine ecosystems.

Question 11

Describe the changes to ice sheets and glaciers since the Industrial Revolution.

Answer 11

Ice sheets and glaciers have been losing mass at an accelerating rate, contributing to sea level rise.

The Greenland and Antarctic ice sheets are particularly vulnerable to warming temperatures.

Question 12

What are the implications of changes to Arctic Sea Ice and glaciers?

Answer 12

Implications include rising sea levels, altered weather patterns, and loss of habitat for polar species.

These changes can also affect global climate systems and human populations.