Climate Change

Question 1

Evidence for Climate Change

Sediment Cores

Answer 1

The remains of organisms in ocean sediments can be analysed to identify environmental conditions, and in turn temperatures, from the last 5 million years

Question 2

Evidence for Climate Change

Tree Rings

Answer 2

tree grows a new ring every year. In warmer, wetter years, tree rings are thicker, Therefore, tree rings can reveal evidence of temperature and weather changes over the past 10,000 years

Question 3

Evidence for Climate Change

Ice Cores

Answer 3

Scientists can analyse the gas levels in ice cores to determine how temperatures have changed over 400,000 years

Question 4

Evidence for Climate Change

Temperature Records

Answer 4

Since the mid-19th century, global temperatures have been measured using a thermometer. This gives accurate short-term data to track changes in temperature

Question 5

Evidence for Climate Change

Pollen Analysis

Answer 5

ollen from plants is preserved in lake beds and bogs. Analysis of pollen can help identify plants that grew in the plast and the periods and climates in which they grew

Question 6

Evidence for Climate Change

Historical Records

Answer 6

Sources such as the Frost Fair drawings, farm produce audits, written descriptions and even cave paintings can reveal information about the climate in a given place and time

Question 7

What is Mitigation

Answer 7

Mitigation strategies aim to reduce the causes of global warming by reducing the concentration of greenhouse gases in the atmosphere

Question 8

Managing Climate Change: Mitigation

Alternative Energy Production

Answer 8

Alternative energy sources such as nuclear power, hydroelectric power (HEP) and solar power, release fewer greenhouse gases than burning fossil fuels
The EU’s Renewable Energy Directive sets a binding target of 20% final consumption from renewable sources by 2020

Question 9

Managing Climate Change: Mitigation

Carbon Capture and Storage (CCS)

Answer 9

Carbon capture involves capturing CO₂ released by industry or through burning fossil fuels and then storing it safely underground. This reduces the amount of CO₂ in the atmosphere
According to the International Energy Agency (IEA), CCS can provide 20% of carbon cuts needed by 2050

Question 10

Managing Climate Change: Mitigation

International Agreements

Answer 10

As part of international agreements, countries agree to common policies, such as reducing greenhouse gases by a set amount by certain dates.
The Paris Agreement (signed by over 170 countries) is one of the main agreements, although the United States withdrew in 2017

Question 11

Managing Climate Change: Mitigation

Planting Trees

Answer 11

Reforestation aims to reverse deforestation by planting trees. As more trees are planted, more CO₂ is removed from the atmosphere
The largest tropical reforestation effort in history, led by Conservation International aims to restore 73 million trees in the Brazilian Amazon by 2023

Question 12

What is Adaptation

Answer 12

Adaptation stratigies aim to limit the negatives effects of climate change on humans

Question 13

Managing Climate Change: Adaptation

Changing Agricultural Systems

Answer 13

In response to changing temperatures and rainfall patterns, agricultural practices may need to be adjusted, such as growing different crops that are more suitable for the conditions, including those that are drought-resistant

Question 14

Managing Climate Change: Adaptation

Managing Water Supplies

Answer 14

With many areas set to get drier, water needs to be managed sustainability. Water meters and water-efficient devices can be installed to encourage reduced water use. The water supply can also be increased through practices such as desalination or recycling rainwater

Question 15

Managing Climate Change: Adaptation

Adjusting to Rising Sea Levels

Answer 15

Sea levels have risen by over 200mm since 1870 and are set to continue rising. Physical defences such as sea walls and barriers reduce the risk of flooding, but these are often very expensive. In LICs, homes built in high-risk areas are often raised on stilts as expensive physical defences are not an option

Question 16

Causes: Natural Factors

Orbital Changes

Answer 16

The Earth’s orbit changes from circular to elliptical which affects its distance from the Sun. When the orbit is more circular, the Earth’s temperature is likely to increase as the Earth is closer to the Sun. When the orbit is elliptical, the temperature is likely to decrease as the earth is further away from the Sun

Question 17

Causes: Natural Factors

Volcanic Activity

Answer 17

Volcanic eruptions release particles of SO₂ and CO₂ into the atmosphere. The SO₂ particles reflect the Sun’s rays, reducing temperatures in the short term. Conversely, CO₂ is a greenhouse gas; it traps the Sun’s heat, resulting in warmer global temperatures

Question 18

Causes: Natural Factors

Solar Output

Answer 18

The Sun’s solar energy output varies over time, which could result changes to the Earth’s climate. However, over the last 50 years, the Sun’s energy output has declined slightly, despite the rise in global temperatures. Therefore, many people reject this theory

Question 19

Causes: Human Factors

Fossil Fuels

Answer 19

Fossil fuels such as oil, gas and coal are burnt to generate energy for transportation, manufacturing and electricty production. However, the process of burning fossil fuels relseases CO₂ into the atmosphere and is the main source of greenhouse gas emissions

Question 20

Causes: Human Factors

Agriculture

Answer 20

Agriculture, especially livestock and rice farming, produces huge amounts of greenhouse gas methane. It is released by animals during digestion and by matter decomposed by microbes in flooded rice paddy fields

Question 21

Causes: Human Factors

Deforestation

Answer 21

Trees asorb CO₂ through photosynthesis. Therefore, clearing trees results in less CO₂ being removed from the atmosphere. This is worsened by the burning of fossil fuels, which also releases greenhouse gases into the atmosphere

Question 22

Effects

On the Environment

Answer 22

1. Global warming causes ice to melt, leading to rising sea levels and harm to polar habitats, including loss of glaciers and ice sheets.
2. Rising sea levels result in more frequent coastal flooding and potential permanent submersion of low-lying areas.
3. Climate change endangers numerous plant and animal species as their habitats are altered or damaged, including coral reefs facing bleaching and destruction due to warmer sea temperatures.
4. Higher temperatures and sea levels bring about an increase in extreme weather events and shifts in precipitation patterns.

Question 23

Effects

Effects on People

Answer 23

1. Global warming raises health risks in hot regions as temperatures increase.
2. Coastal and extremely hot areas face inhabitable conditions, leading to mass migration and overcrowding.
3. Warmer temperatures exacerbate drought, desertification, and crop yield decline in many regions.
4. Widespread food and water shortages arise from drought and reduced crop production.