Problem 2 - Campbell Biology

Question

Knowledge/Comprehension The main cause of the increase in the amount of CO2 in Earth's atmosphere over the past 150 years is (A) increased worldwide primary production. (B) increased worldwide standing crop. (C) an increase in the amount of infrared radiation absorbed by the atmosphere. (D) the burning of larger amounts of wood and fossil fuels.

Step-by-Step Solution

Answer

(D) the burning of larger amounts of wood and fossil fuels.

Step 1: Understand the Question

Identify what is being asked. The question asks for the primary cause of the increase in CO2 levels in the Earth's atmosphere over the last 150 years.

Step 2: Examine Each Option

Review each answer choice to determine which one correctly identifies the cause.

Step 3: Analyze Option A

Increased worldwide primary production refers to the increase in photosynthetic activity, which actually removes CO2 from the atmosphere. Therefore, it is not the cause of the increase in CO2.

Step 4: Analyze Option B

Increased worldwide standing crop refers to more biomass being present, which also does not explain the increase in CO2 levels.

Step 5: Analyze Option C

An increase in the amount of infrared radiation absorbed by the atmosphere is a consequence of higher CO2 levels, not a cause of it.

Step 6: Analyze Option D

The burning of larger amounts of wood and fossil fuels releases significant amounts of CO2 into the atmosphere, making this the most likely cause of the increase in CO2 levels over the past 150 years.

Step 7: Select the Correct Answer

Option D correctly identifies the primary cause of the increase in CO2 levels in the Earth's atmosphere over the past 150 years.

Key Concepts

carbon emissions

Carbon emissions refer to the release of carbon dioxide (CO2) into the atmosphere. These emissions are a significant contributor to global warming and climate change.
They primarily result from human activities, such as driving cars, manufacturing goods, and generating electricity.
When fossil fuels like coal, oil, and natural gas are burned, they release large amounts of CO2.
Additionally, deforestation and industrial processes also contribute to carbon emissions.
Limiting carbon emissions is crucial for reducing the impact of climate change and involves efforts like using renewable energy, increasing energy efficiency, and reforestation.

fossil fuels burning

Burning fossil fuels is one of the largest sources of CO2 emissions. Fossil fuels are energy sources formed from the remains of ancient plants and animals. They include coal, oil, and natural gas.
When these fuels are burned for energy, they release CO2 and other greenhouse gases into the atmosphere.
This process significantly contributes to the increase in atmospheric CO2 levels noticed over the past 150 years.
For instance:

• Coal is often used in power plants for electricity generation.
• Oil is refined into gasoline and diesel for transportation.
• Natural gas is used for heating and electricity.

Shifting away from fossil fuels to more sustainable energy sources like wind, solar, and hydro can greatly help in reducing CO2 emissions.

greenhouse gases

Greenhouse gases are gases in the Earth's atmosphere that trap heat. The main greenhouse gases include:

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

These gases create a 'greenhouse effect' by allowing sunlight to enter the atmosphere but preventing some of the resulting heat from escaping back into space.
This effect is essential for maintaining Earth's temperature.
However, human activities, like burning fossil fuels and deforestation, have significantly increased the concentration of these gases, particularly CO2, enhancing the greenhouse effect and leading to global warming.
Reducing greenhouse gas emissions is essential for mitigating the effects of climate change and involves international cooperation, technological innovation, and widespread behavioral changes.