This blog has been created as a forum for examining recent developments in Science education. We are graduate students at the Faculty of Education at the University of Windsor in Windsor, Ontario, Canada.

Monday, January 17, 2011

Challenges Educators Face

Teachers face a myriad of challenges in teaching climate change. These challenges may include:

1) Making the content relevant to the students;

2) Convincing the students that their actions can make a difference;

3) Inspiring the students to make eco friendly choices.

Sunday, January 16, 2011

Impacts of Climate Change

1. Affect on humans - food scarcities, heat stress, increased air pollution.

2. Decreased arctic sea ice cover.

3. Projected flooding in coastal regions.

4. Ecosystem changes - e.g., plants flowering earlier during the year.

5. Longer growing seasons - could harm native
plant and animal species.

6. Snow pack decreases on mountain ranges - affects fish populations,
hydropower, and water availability.

Climate Change Facts

The article Understanding and Responding to Climate Change (The National Academies, 2008), presented considerable evidence for the existence of climate change. These facts include:
  • Temperatures have risen by 1.4 degrees fahrenheit since the start of the 20th century, much of which has occurred in the last 30 years.
  • Global mean surface temperatures are higher during the last few decades of the 20th century than during any comparable period since at least AD 1600.

Most scientists agree that this warming is primarily caused by human activities that have increased the amount of greenhouse gases in the atmosphere (H2O, CO2, CH4, N2O, O3). In fact, CO2 levels are at their highest in at least 650,000 years and continue to rise.

How do we know that human activities are changing the Earth's climate?
  • There is a concurrent increase in surface temperature with CO2 and other greenhouse gases during the past century.
  • Geographical pattern of observed warming with greater temperature increases over land and in polar regions than over the oceans.

Dr. Jane Goodall: A Reason for Hope

On September 25, 2006, I attended a lecture entitled, “A Reason for Hope” where primatologist Dr. Jane Goodall discussed the power of the individual. I was inspired by her message:
Every individual matters
Every individual has a role to play
Every individual makes a difference


Dr. Goodall stated that one person who independently attempts to make a difference faces obstacles but if each person works collectively making a difference becomes possible. That is, if teachers work mutually toward change, then change becomes easily accessible. In other words, change is greater in numbers.

What Warms and Cools the Earth?

There are three critical elements that affect the Earth's temperature change - greenhouse gases that warm the planet, human activities, and natural processes.  

Climate forcings (i.e., something that is imposed externally on the climate system by either human activities or natural processes) or climate feedbacks (i.e., an energy change that is produced within the climate system itself in response to a climate forcing).

Greeenhouse Gases Warm the Planet

The Greenhouse Effect
Carbon dioxide (CO2) can be emitted naturally through the carbon cycle and through human activities. Since the Industrial Revolution in the 1700's, carbon dioxide concentration levels are increasing primarily due to the burning of oil, coal and gas, and deforestation.

Methane (CH4) is a greenhouse gas that remains in the atmosphere for approximately 9-15 years. Methane is over 20 times more effective in trapping heat in the atmosphere than carbon dioxide (CO2) over a 100-year period and is emitted from a variety of natural and human-influenced sources (e.g., raising livestock, growing rice, filling landfills, natural gas and petroleum systems, wastewater treatment).

Nitrous oxide (N2O), commonly known as the laughing gas, is a colourless, non-flammable gas with a slightly sweet taste and odour. Agricultural activities and land use changes have contributed to the increasing concentration levels.

Ozone (O3) forms naturally in the upper atmosphere, where it creates a protective shield that intercepts damaging ultraviolet radiation from the Sun. However, when ozone forms in the lower atmosphere, it becomes an air pollutant that has harmful effects on the respiratory systems of animals and will burn sensitive plants.

Halocarbons and chlorofluorocarbons (CFCs) are chemicals that have specialized uses in industries, such as refrigerants, fire retardants, adhesives, and pesticides. They have contributed to the damage of the ozone layer and as a result, most production of CFSs has been banned and concentrations levels are beginning to decline.

Human Activities Affect the Earth's Temperature
Most aerosols, such as sulfate (SO4), cool the planet by reflecting sunlight back to space. Human activities, such as industrial processes, produce many different kinds of aerosols and the cooling of these aerosols produce one of the greatest remaining uncertainties in understanding present and future climate change.

Deforestation
Deforestation and other changes in land use modify the amount of sunlight reflected back to space from the Earth's surface. Changes in land use can lead to positive and negative climate forcing locally, but the net global effect is a slight cooling.

Black carbon particles or "soot,"is produced when fossil fuels or vegetation are burned, generally have a warming effect because they absorb incoming solar radiation.

Natural Processes Affect the Earth's Temperature

Volcanic Eruption
The Sun is Earth's main energy source. The Sun's output is nearly constant, but small changes over an extended period of time can lead to climate changes.

Volcanic eruptions emit many gases. One of the most important of these is sulfur dioxide (SO2), which, once in the atmosphere, forms sulfate aerosol (SO4). Large volcanic eruptions can cool the Earth slightly for several years, until the sulfate particles settle out of the atmosphere.