Climate Change Science

Frequently Asked Questions


What is climate change?
Climate change is any significant change in climate, including temperature, precipitation or wind patterns, lasting for an extended period of decades or longer.

What are greenhouse gases (GHGs)?
Greenhouse gases are gases that absorb infrared radiation in the atmosphere. Greenhouse gases include, but are not limited to, water vapour, carbon dioxide, methane and ozone.

What is the difference between climate change and global warming?
Global warming is the increase in the Earth's temperature due to the build-up of greenhouse gases in the atmosphere. Climate change broadly refers to long-term changes in climate like average temperature or precipitation.

How does the "greenhouse effect" affect climate?
The greenhouse effect is the trapping and build-up of heat in the atmosphere near the Earth's surface. As the concentration of greenhouse gases in the atmosphere increases, the average temperature of the Earth's atmosphere increases.

What causes climate change?
Climate change is caused by natural factors, such as changes in the sun's intensity or slow changes in the Earth's orbit around the sun, natural processes within the climate system like changes in ocean circulation. Climate change is also caused by human activities that change the atmosphere's composition through burning fossil fuels and the land surface through deforestation, reforestation, urbanization and desertification.

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Which human activities have the greatest GHG emissions?
The burning of fossil fuels in cars, factories and electric power plants currently accounts for 85 per cent of the carbon dioxide contributed to the atmosphere.

Does the hole in the ozone layer affect climate change?
Ozone is a gas that occurs naturally in the atmosphere. The ozone layer blocks incoming ultraviolet radiation from the sun. As the hole in the ozone gets bigger, the more ultraviolet radiation which is harmful to plants, animals and humans, can reach the earth.

How good are the computer models used to model climate?
They are very sophisticated and the technology has advanced enormously in the last 20 years. Models can now track characteristics of the atmosphere, geology, topography, vegetation, carbon cycle and much more, using high resolution grids.

Isn’t global cooling a danger, not global warming?
Researchers believed pollution in the atmosphere, shading the planet and blocking sunlight, was causing a global cooling, but since the 1970's, clean air laws began reducing sun blocking pollutants.

If global warming is real, why are winters still so cold?
Different parts of Earth's ecosystem respond to the greenhouse effect differently. So while there may be warm or cold spells in every area, studies show that the earth's average temperature is increasing.

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What can we do about global warming?
Change your habits to help reduce greenhouse gas emissions and promote the use of environmentally friendly products and services.

How does climate change impact weather?
Climate change affects air pressure, which is the source of all weather. Changes in air pressure create wind, change the temperature of air columns and affect uptake of water from oceans. All of these increase the potency of weather events, making winds stronger and driving more intense storms.

How does climate change impact water and water resources?
Climate change causes a change in water level, temperature and flow. As the temperature increases groundwater, streams, rivers and wetlands diminish and glaciers melt. These changes increase the severity of floods and drought.

How does climate change impact human health?
Climate change will intensify air pollution like smog and cause greater outbreaks of asthma and heart disease. As it disrupts ecosystems, water-borne illnesses will become more frequent.

What is the United Nations Framework Convention on Climate Change (UNFCCC)?
A committee comprised of 192 countries that sets an overall framework for intergovernmental efforts to tackle the challenges posed by climate change.

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What is the Kyoto Protocol?
The Kyoto Protocol is an international agreement developed by the UNFCCC committing countries to reduce their greenhouse gas emissions.

What is COP and what does it stand for?
COP stands for Conference of the Parties. It is the supreme body of the UNFCCC that periodically reviews existing commitments in light of the conventions objective, new scientific findings and the effectiveness of national climate change programs.

Who attends/ participates at COP's?
Representatives from all 192 countries that are members of the COP attend. Representatives from the United Nations, its specialized agencies and related organizations attend as well as more than 985 non-governmental organizations and 67 intergovernmental organizations.

What does Canada do at COP meetings?
As a member of the Party of COP and participates is the annual meetings and negotiations.

What do major scientific organizations say about the impact of human activity on climate change?
Major scientific organizations are in agreement that human energy use that creates greenhouse gases and aerosols is driving an increase in temperature. They also state that humans must collaborate through science, technology, industry and government to reduce climate change and create ways to adapt to it.

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What is the Intergovernmental Panel on Climate Change (IPCC)?
The IPCC is the official advisory body on the science of climate change and measures to reduce its consequences. Established in 1988 by the United Nations Environment Programme and the World Meteorological Organization, the IPCC assess information on the issue of climate change.

Are IPCC reports political or scientific documents?
The IPCC report is a scientific report. Researched, created and reviewed by scientists. The Summary for Policymakers is a condensed version of the report delivered by diplomats with scientists on hand to ensure no information is distorted.

What is Canada's climate change plan?
The Government of Canada supports an aggressive approach to climate change that achieves real environmental and economic benefits for all Canadians. View Canada’s Action on Climate Change.

What is Ontario's climate change plan?
Ontario's plan to fight climate change, called Go Green includes new regulations for greenhouse gas emissions, a conservation plan, phasing out the use of coal and inefficient light bulbs, phasing in more renewable energy sources and providing tax breaks, rebates, programs and incentives for energy audits, efficient products and municipalities going green.

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