Climate Change

Climate Change

Climate change is fast becoming a critical issue both globally and locally. It is the single biggest challenge of our time – affecting every aspect of our daily lives, from the food we eat to the extracurricular activities we enjoy. Since the Industrial Revolution, when we began burning coal and then oil, people have been changing the planet’s climate. The greenhouse gas (GHG) producing activities by our society up to now will continue to impact us well into the future. The changes we make today, will only serve to better the conditions for future generations, such as our children, and their grandchildren.

What is the difference between weather and climate?

Climate is a length of time in which temperatures are observed, with climate being the average weather over a longer period of time (i.e., annual or multi-year). Weather is what happens outside every day. Both weather and climate include measurements of temperature and precipitation (i.e., rain, snow), but because climate is measured over a longer period of time – patterns or trends can be seen.

A change in the Earth’s climate could have a major impact on the environment. Ecosystem processes (like plants and trees flowering in spring) and technologies that we are surrounded by (like the electricity grid) are designed to work in certain predictable conditions. When those conditions change or become more unpredictable, ecosystem processes and technologies may begin to break down.

What is climate change?

Climate change is a long-term shift in weather conditions identified by changes in temperature, precipitation, winds, and other indicators. Climate change can involve both changes in average conditions and changes in variability, including, for example, extreme events.

What are greenhouse gases (GHGs)?

Greenhouse gases are gases that absorb infrared radiation in the atmosphere. Some of the most significant GHGs include but are not limited to, water vapour (H2O), carbon dioxide (CO2), methane (CH4) and ozone (O3).

What is the greenhouse gas effect?

Greenhouse gases (GHGs) are gases that are naturally present in the atmosphere which absorb and emit radiation in the form of heat. They consist mainly of water vapour, carbon dioxide, methane (CH4 ), nitrous oxide (N2O), and ozone (O3), and although they get a bad reputation they are not entirely bad. Without them, the Earth’s average surface temperature would be about 33 degrees Celsius colder, rendering the Earth uninhabitable.

Greenhouse gases are released through natural processes such as vegetation decay and forest fires as well as through anthropogenic activities like land-use changes and industrial processes. When greenhouse gases are produced by natural means they contribute to the natural greenhouse effect which is responsible for heating our planet and keeps Earth from looking like Mars.

However, when these gases are produced from anthropogenic sources they increase the concentration of greenhouse gases in the atmosphere, which amplifies the natural greenhouse effect. Anthropogenic greenhouse gases and their enhancement of the greenhouse effect are the primary drivers of climate change.

Greenhouse gases insulate the Earth from cold surrounding space. They absorb heat from the sun and emit it back to the Earth, warming the surface. As the surface of the Earth increases in temperature it emits heat back into the atmosphere. Some of this is absorbed again by greenhouse gases. Part of this absorbed heat is then re-emitted back to the Earth’s surface and it is this bounce-back action that can create problems. As the concentrations of greenhouse gases in the atmosphere increase, so does the amount of heat that is bounced back to the Earth’s surface and as a result the Earth warms.

This effect is like adding multiple blankets while you’re sleeping. While the first blanket might keep you warm and sleepy, the fourth blanket (or more) will make it so warm that it is hard to sleep. This is not because your body is producing more heat. Rather it is because each additional blanket prevents more body heat from escaping into the surrounding room. It is the same for the Earth. It is not that the sun is producing more energy; instead, increasing concentrations of greenhouse gases are ’blanketing’ the Earth. As a result, the Earth warms more rapidly.

What human activities contribute the greatest amount of GHGs?

Earth has experienced a natural fluctuation in GHGs overtime. But, human activity has contributed to higher concentrations of GHGs which is causing an increase in temperature, and in turn, an acceleration of climate change. In Ontario, greenhouse gas emissions come from many sources. Emissions mainly come from burning fossil fuels for transportation, from industry, and from the energy needed for commercial and residential buildings. Other emissions also come from the agricultural sector, waste disposal, and electrical generation.

What is the difference between global warming and climate change?

Climate change refers to a long-term shift in weather conditions, including temperature, precipitation, winds, and other indicators. This may vary from region to region. For example, temperature increases will vary from one region to another, and precipitation may increase in some regions but decrease in other regions.

Global warming refers specifically to an increase in the global average surface temperature. Global warming is an indicator of climate change.

What exactly do we mean when we talk about Earth’s climate system and climate change?

Climate change refers to a long-term shift in weather conditions. It is measured by changes in a variety of indicators including temperature, precipitation, wind and water levels. The data gathered depicts the changes in both average and extreme conditions, and may vary drastically across regions. For example, climate change is expected to affect Africa and Canada differently.

Climate change is a term that is often used to refer only to the surface temperature record of Earth, but there are more components to the climate system. The climate system is complex and includes the atmosphere (air), hydrosphere (water), cryosphere (snow and ice), lithosphere (rocky surface of Earth), and biosphere (plants and animals). The complexity of this system makes climate change more significant than simply overall warming.

How does climate change affect 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. More extreme storms can cause injuries and illnesses, as well as community-wide emergencies, and warming temperatures will attract more insects that carry vector borne diseases such as West Nile Virus and Lyme disease.

Did you know?

The International Panel on Climate Change (IPCC) defines:

Mitigation as an anthropogenic intervention to reduce the sources or enhance the sinks of greenhouse gases.

Adaptation as the process of adjustment to actual or expected changes, in order to moderate harm or exploit beneficial opportunities.

Fact v. Myth

Myth: CO2 is removed from the atmosphere fairly quickly, so we can wait to take action until after we start to see dangerous impacts from climate change.

Fact: CO2 and other GHGs have the potential to remain in the atmosphere for many centuries. Even if we were to elimate emissions today, it would take centuries for the heat-trapping GHGs now in the atmosphere to fall to pre-industrial levels. We need to reduce our emissions now, in order to avoid the increasingly dangerous and irreversible consequences of climate change.

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