Climate Change and Global Warming: nature versus nurture

The driving forces of nature are captured in the Kwaj sunrise.
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Since 1970, temperatures have increased at approximately three times the average for the 20th century. Is this change in weather a natural phenomenon that we have no control over or is it a result of human activity?  Or, perhaps it is a result of both natural forces and human activity. Can we intervene?

The Greenhouse Effect [1]
Carbon dioxide and methane are examples of gases that allow sunlight to reach the Earth and prevent some of the resulting heat from radiating back out into space. This produces the greenhouse effect, which has been part of the Earth’s process since its formation. Without this activity, the planet would not have warmed enough for life to form. Since the time of the Industrial Revolution in 1750, human activities have involved burning fossil fuels and emissions of aerosols that absorb and emit heat and reflect light. This contributes to the concentration of heat-trapping greenhouse gases in the atmosphere and the consequential greenhouse effect.
 

The Greenhouse effect.
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Some greenhouse gases are produced naturally and are emitted into the atmosphere through a natural process as well as through human activities. Other greenhouse gases are produced and emitted only through human activities.
•    Carbon Dioxide (CO2): This gas enters the atmosphere through burning of fossil fuels (oil, natural gas, coal), solid waste, trees, and wood products. Plants absorb this gas as part of the biological carbon cycle and remove it from the atmosphere.
•    Methane (CH4): This gas is emitted during the production and transport of coal, natural gas and oil, from livestock and other agricultural practices, and by the decay of organic waste in municipal solid waste landfills.
•    Nitrous Oxide (N2O): This gas is emitted during agricultural and industrial activities and from combustion of fossil fuels and solid waste.
•    Fluorinated Gases: These powerful synthetic gases include hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride, which are emitted from various industrial processes. They are used as substitutes for ozone-depleting substances (CFCs, HCFCs, halons) and are emitted in small quantities yet are highly potent greenhouse gases (sometimes referred to as High Global Warming Potential gases or High GWP gases).

Atmospheric CO2 levels.
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Theories
Human Activity [2][3][4]
In 2001, the United Nations scientific panel, or Intergovernmental Panel on Climate Change (IPCC), reported it was likely that humanity played a role in the warming trend by adding to the heat-trapping greenhouse gases already present in the atmosphere. In 2007, the panel reported that there was clear substantial evidence of a warming trend and that human activity was very likely the driving force behind it over the last 50 years. This statement appeared to confirm the accumulating scientific evidence that the release of CO2 and other heat-trapping gases from smokestacks, tailpipes and burning forests play an influential and key role in raising the average surface temperature of the Earth by more than 1 degree Fahrenheit since 1900. It also compelled people to focus on what to do about greenhouse gases. Business groups have come together to push for federal regulation; former Vice President Al Gore's documentary, "An Inconvenient Truth," highlighted the issue and was awarded an Oscar. The Supreme Court made its first global warming-related decision, ruling 5 to 4 that the Environmental Protection Agency (EPA) had not justified its position that it was not authorized to regulate CO2. But can we accurately conclude that human activity is responsible for the warming trend?
 

Al Gore: An Inconvenient Truth
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Cosmic Rays [5]
When cosmic rays, originating from outside the solar system, hit the Earth's atmosphere highly energetic particles create microscopic aerosols. These aerosols collect in the atmosphere and act as nuclei for water droplet formation, which can result in a large-scale cloud cover. Cloud cover reflects light from the sun, which results in cooling the Earth. This is a global dimming effect, which could provide clues to the debate on global warming since it is an influential factor in the amount of radiation entering the atmosphere. The flux of cosmic rays is actually dependent on the sun's magnetic field that varies over an 11-year solar cycle. But are changes in cosmic rays too feeble to cause the necessary changes in clouds and affect climate change?

Solar Activity [6]
Solar activity, which follows an eleven-year cycle, may have a subtle effect on climate change. The 11-year solar cycle causes a rise and fall in cosmic rays reaching the Earth's surface and so causes a rise and fall in lightning activity. Decreased solar activity means higher cosmic rays flux with fewer lightning storms. Maximum solar activity results in fewer charged particles in the atmosphere and so is more resistant to the smooth flow of charge, and lightning bolts occur as resistance breaks down. This lightning effect is also affected by the amount of particulate matter in the atmosphere, which depends on fossil fuel burning. These factors influence cloud cover and depending on the specific point at which we are in the solar cycle, the effect of particulates from fossil fuel burning may have a positive or negative effect on storms, cloud cover, and the Earth's ability to reflect away energy from sunlight. When solar activity is close to its minimum, cosmic rays will increase cloud cover and lightning, which will almost completely cancel out the warming effect of added greenhouse gases at that point in time. But is solar activity strong enough to cause the present climate change?

Other Factors [6]
Several other factors influence climate change including long term influences that have been in existence for hundreds of thousands of years and so should be considered in climate models. These factors have an astronomical origin, such as axial tilt and precession (slow gyration) of the Earth's orbit. Natural processes on Earth, such as volcanic activity and lightning, also affect the levels of particulates in the atmosphere and, consequently, affect climate. Higher levels of particulates in the atmosphere increase cloud cover, which reduces the amount of energy from sunlight absorbed by the Earth's surface. But is there enough evidence to conclude that these factors are influential enough to affect climate change on a global basis?

Graph depicting the correlation between cosmic ray flux (red) and change in temperature (black); Graph of storm activity over time.
Photo credit: (1) (2)
 

Effects of Climate Change [7]
The climate crisis has put us in danger and may even be considered a planetary emergency. Scientists of all nations have made a collaborative effort to alert people that they must work together to solve the crisis. The evidence strongly suggests that if we do not act assertively to deal with the underlying causes of global warming, the world will experience devastating catastrophes. Effects of climate change (past, present and/or future) include:
•    More frequent and stronger storms.
•    Melting the North Polar ice cap and all mountain glaciers in the world.
•    Destabilization of the massive mound of ice on Greenland and the enormous mass of ice on top of islands in West Antarctica, which will result in a worldwide increase in sea levels by about 20 feet.
•    Disruption of ocean and wind currents that has been in place since before the first cities were built almost 10,000 years ago.
•    So much CO2 is being absorbed into the oceans that if we continue at the current rate, it will increase the saturation of calcium carbonate to levels that will prevent formation of corals and interfere with the production of shells by sea creatures.
•    Increasing temperatures and the destruction of forests and other critical habitats through cutting and burning causes loss of living species and is at a level comparable to the extinction event that wiped out the dinosaurs 65 million years ago.

The leopard seal is the top predator in Antarctica; but for how much longer?; An effect of climate change. Antarctica: The Global Warming: (c) 2007 Sebastian Copeland; Graph of glacier thickness.
Photo credit: (1) (2) (3)
 

Predictions [2][8]  
Most recently, the IPCC predicted that the climate is likely to rise between 3.5 and 8 degrees Fahrenheit on a global level if the atmospheric concentration of CO2 reaches twice the level it did in 1750. By 2100, sea levels will rise between 7 to 23 inches and the changes we are now experiencing will continue for centuries to come. According to scientists from the National Center for Atmospheric Research in Boulder, Colorado, even without cosmic rays, a 0.1 percent change in the sun’s energy output is enough to trigger El Niño- and La Niña-like events that will influence weather around the world. Climate modeling illustrates that over largely cloud-free areas of the Pacific Ocean, extra heating over several years warms the water and increases evaporation. This activity intensifies tropical storms and trade winds in the eastern Pacific, which causes cooler-than-normal waters, as in a La Niña event. In a couple of years, the cool water pattern evolves into a pool of El Niño-like warm water. Although many human sources of greenhouse gas emissions are expected to rise in the future, this growth can be reduced through the use of modern, cleaner technologies. Choices about commuting, housing, electricity and recycling can also influence the amount of greenhouse gases being emitted. But can anyone really accurately predict what will happen as a result of climate change if it is really a natural process beyond human control?
 

Nature versus Nurture
Nature [9][10][11]
•    Professor Bob Carter, a geologist, uses the scientific method to examine the theory about the link between global warming and CO2 levels. He examined the hypothesis and found that it fails the test. Perhaps temperature change really isn’t that unusual and it may even get cooler as time goes on.
•    Authors Henrik Svensmark and Nigel Calder wrote a book, The Chilling Stars: The New Theory of Climate Change, in which they present a cosmic view of climate change. They explain the theories about cosmic rays, solar activity, sunspot activity, cloud formation and their effects on climate change. They also discuss how CO2 is produced mainly from sea life in the ocean and that the warming of the ocean results in a release of the gas into the atmosphere instead of being dissolved in sea water. Solar activity has an influential effect on the ocean temperature and, subsequently, CO2, but takes years to affect a change. Human activity produces CO2 but it is considered a tiny fraction of the whole that is emitted through natural processes. The ocean periodically takes up the CO2 anyway, or gives it off, depending on its temperature. The thought is that the CO2 content of the atmosphere is a result of ocean temperature, rather than a cause.
•    The Gaia hypothesis, originating in the 1960s, is a theory based on the idea that the biomass self-regulates the planetary conditions to make its physical environment on the planet more hospitable to the species that live in it. It does this, more specifically, through the regulation of atmospheric temperature and chemistry, which maintains environmental homeostasis. A mathematical model is used to illustrate this hypothesis through a computer simulation known as Daisyworld, which depicts a hypothetical world orbiting a sun whose radiant energy is slowly increasing. But are any of these ideas convincing enough to form an objective conclusion that human activity is not making a significant impact on climate change; or can this scientific evidence allow us to perhaps engineer devices to halt climate change since it is based on measurable outcomes?
 

Nurture [7]
•    The national academies of science in 11 of the most influential nations came together a few years ago to call on every nation to "acknowledge that the threat of climate change is clear and increasing" and to declare that the "scientific understanding of climate changes is now sufficiently clear to justify nations taking prompt action." Their message is clear—take a stand and protect (and respect) the Earth. There is voluminous evidence that emission of greenhouse gases such as CO2, CH4, N2O, and fluorinated gases are polluting the atmosphere and affecting a change in environmental conditions on a global basis. These changes can be seen in temperature, storm activity, sea levels, and living species. But is human activity really responsible for this global change or are the fears that we are affecting and devastating our planet unfounded; or can we really do something to intervene and restore a healthy environmental balance on planet Earth?
 

Climate Change: Is CO2 the cause? (4-part series)
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We have reached a level of global warming and the entire planet is affected by the results of climate change. Although there are several theories that offer explanations as to why this event is occurring, the link between human activity (emitting greenhouse gases into the atmosphere), cosmic rays, solar activity, the earth’s tilt and precession of its orbit, volcanic activity, lightning and other factors is still a subject of debate and remains controversial. Some scientists do not necessarily support the idea that human activity is responsible, at least not to a significant degree. They believe that natural causes are the driving force behind climate change and that there is insufficient evidence to support ideas to the contrary. On one level, we can make a difference by keeping our environment clean and healthy for now and for future generations by following guidelines designed to be environmentally friendly. It may or may not be enough to halt the current trend in climate change that is affecting us on a global level, but it does make an impact on healthier living. Climate change is affecting our planet. But is this change driven by natural processes that are beyond our control; or are we nurturing these changes and the consequential effects on the planet through human activity?

Can we intervene in the climate change crisis?
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Reference links:
1.    http://www.epa.gov/climatechange/emissions/index.html#ggo
2.    http://topics.nytimes.com/top/news/science/topics/globalwarming/index.html
3.    http://vodpod.com/watch/1464666-an-inconvenient-truth?mp=1&pod=erwsus
4.    http://www.climatecrisis.net/
5.    http://www.universetoday.com/2008/03/20/could-cosmic-rays-influence-global-warming/
6.    http://www.sciencedaily.com/releases/2009/07/090721090127.htm
7.    http://www.npr.org/templates/story/story.php?storyId=5441976
8.    http://www.nytimes.com/2009/07/21/science/space/21sunspot.html?_r=2&pagewanted=all
9.    http://www.youtube.com/watch?v=FOLkze-9GcI
10.  http://hypsithermal.wordpress.com/2008/03/11/the-chilling-stars-redux/
11.  http://en.wikipedia.org/wiki/Gaia_theory_(science)
 

Copyright ©2009 Joyce E.M. Wall