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CLIMATE CHANGE
Climate Change
Rebecca Royten
Concordia University
The Earth is warming. The average temperature of the Earth has risen by 1.4 degree over the
past century (Environmental Protection Agency, 2014). This is a scientific fact not in dispute, and there
are many other facts to support that the climate is changing. There has been a worldwide decline since
the mid-1960s in areas covered by snow and glaciers and an average rise in sea level of 1.8 millimeters
per year from 1961 to 2003 (Maxwell, 2014). The rate of rise in sea level in the last decade is nearly
double that of the last century and the acidity of surface ocean waters has increased by 30% (National
Aeronautics Space Administration, 2014). All three major global surface temperature reconstructions
show that the Earth has warmed since 1880. Most of this warming has occurred since the 1970s with
the 20 warmest years having occurred since 1981 and with all ten of the warmest years occurring in the
past 12 years (NASA, 2014). Global carbon emissions from fossil fuels have significantly increased since
1900. Emissions increased by over 16 times between 1900 and 2008 and by 1.5 times between 1900 and
2008 (EPA, 2014). The heat trapping nature of carbon dioxide and other greenhouse gas emission was
demonstrated in the mid-19th century (NASA, 2014). Ice cores drawn from Greenland, Antarctica and
other tropical mountain glaciers have shown that the Earth’s climate responds to changes in solar
output, in the Earth’s orbit and in greenhouse gas levels (NASA, 2014). Greenland and Antarctic ice
sheets have decreased in mass and the glaciers are retreating almost everywhere including the Alps,
Himalayas, Andes, Rockies, Alaska and Africa (NASA, 2014). The number of record high temperature
events in the U.S. have been increasing while the record number of low temperature events have been
decreasing (NASA, 2014). These are all effects that scientists have predicted in the past that would result
from global climate change (NASA, 2014). These are scientifically measured evidence of changes in the
climate and they are irrefutable. I think there should be scientific consensus over the fact that the
climate is changing. To disregard the evidence is a disservice to those who are trying to negate the
effects of these climate changes.
What can and is challenged is the causes of these climate changes. The main argument is
whether there is human causation or natural causation. Ninety seven percent of climate scientists agree
that climate warming trends are due to human activities (NASA, 2014). There are other respected
organizations that believe that nature not human activity is the primary responsibility for climate change
(ProCon, 2014). They contest that the warming of 1.4 degrees is within the range of the past 3,000 years
citing a study done by the Harvard-Smithsonian Center for Astrophysics that shows temperatures from
1000-1110 AD are comparable to temperatures from 1900-1990 (ProCon, 2014). There are those in the
scientific community that believe that rising CO2 levels are a result of global warming not a cause, that
as temperature increases CO2 is released from carbon sinks like the oceans or the Arctic tundra (ProCon,
2014). Scientists that support human causation claim that human produced CO2 is warming the Earth
not the natural CO2 from carbon sinks. The CO2 from fossil fuel combustion has a specific isotopic ratio
that is different from the CO2 released from carbon sinks and it can be measured in the atmosphere
(ProCon, 2014). Another example of disagreement of causation is that global warming and cooling can
be caused by fluctuations of the sun’s heat, not by the minor effect human produced gasses have on
greenhouse gasses (ProCon, 2014). Climate is influenced by natural changes, including the sun itself
(EPA, 2014). The sun itself can affect the intensity of the sunlight that reaches the Earth which can cause
warming and cooling of the Earth (EPA, 2014). In the past the sun has influenced the Earth’s climate, but
solar activity has been relatively constant since the mid-20th century and so for those who stand behind
human causes the sun does not explain the recent warming (EPA, 2014). I think it is good to debate and
discuss all options in what may or may not be affecting climate change. Debate brings new ideas and
new solutions. The effects of climate change impact our health, environment and economy (EPA, 2014).
These are important areas and all causes and all solutions should be investigated.
Environmental Protection Agency. (2014). Climate change science overview. Retrieved from
http://www.epa.gov/climatechange/science/overview.html
Maxwell, N. (2014) Producing energy. In Understanding Environmental Health. Jones and Bartlett
Learning, LLC an Ascend Learning Company (pp 147)
National Aeronautics Space Administration. (2014). Climate change: how do we know?. Retrieved from
http://climate.nasa.gov/evidence
ProCon. (2014). Climate change debate- pros and cons. Retrieved from http://climatechange.procon.org