OCR A-Level Geography H481
Coastal Landscapes
Glaciated Landscapes
Dryland Landscapes
Earth’s Life Support Systems
Changing Spaces; Making Places
Trade in the Contemporary World
Global Migration
Human Rights
Power and Borders
Climate Change
Disease Dilemmas
Exploring Oceans
Future of Food
Hazardous Earth
Geographical Skills
Climate Change
Why greenhouse gas emissions have risen since the pre-industrial era
- 2 things to know
- Component 03
Overview
Recall questions on fossil fuel combustion as the main CO₂ source, today's concentration and the Mauna Loa record, population growth and affluence, deforestation, agricultural methane and nitrous oxide from fertiliser, cement making, the rise in methane, halocarbons, electricity demand, and the acceleration after 1950.
What you need to know
Answer each one before you reveal it.
Explain how population growth has driven the rise in emissions.
Questions from this subtopic
Each one with the model answer underneath.
- 1
What is the single largest source of anthropogenic CO₂?
Model answer
The combustion of fossil fuels, meaning coal, oil and natural gas, for energy.
- 2
State the approximate present concentration of atmospheric CO₂ and how it compares with pre-industrial levels.
Model answer
It now exceeds 420 parts per million, half as much again as the pre-industrial figure of 280 parts per million.
- 3
Which measurement record first demonstrated the year-on-year rise of atmospheric CO₂?
Model answer
The continuous record begun at Mauna Loa in Hawaii in 1958, which shows a steady upward trend with an annual oscillation superimposed on it.
- 4
Why does the Mauna Loa record of CO₂ show a sawtooth pattern within each year?
Model answer
Northern Hemisphere vegetation draws CO₂ down during the growing season and releases it again as leaves die back, producing an annual dip and recovery.
- 5
Explain how population growth has driven the rise in emissions.
Model answer
Global population has risen from about 1.6 billion in 1900 to roughly 8 billion today, and every additional person requires energy, food, housing and transport.
- 6
Why does rising affluence increase emissions faster than population growth alone?
Model answer
Higher incomes bring car ownership, air travel, meat consumption, appliances and larger homes, so emissions per person rise alongside the number of people.
Other ways to work this
The same content, four other ways.
What is inside Levo
Six ways to work the same material.
Every question in Climate Change, on a schedule.
Attempt a question from memory, write the correct version, then attempt it again. Levo records the jump between your first attempt and your last, and brings each question back on the day you are due to forget it.
Or £46 a year, about £3.83 a month. Cancel anytime.