Global Warming: Cause and Mitigation Your Name Professor Name SCI 110 – Introduction to Physical Science June 12, 2013 Global warming, also referred to as climate change, is real. The question remains, is man or Mother Nature responsible for causing it? The Nobel Prize-winning chemist Svante Arrhenius first proposed the idea of global warming in 1896. He knew that carbon dioxide traps heat in the earth’s atmosphere and that burning fossil fuels releases CO2 (Bryan). We know that there are some things that naturally cause climate change and are not in our control.
Among them are small explosions on the sun which cause an increase in the normal heat output emitted by the sun, volcanic eruptions that cause a decrease in temperature due to the smoke and gas they put into our atmosphere, and the axis and tilt of our planet earth. Because the earth does not rotate around the sun in a perfect circle, a change in orbit can move the earth closer or farther away from the sun, our provider of heat and light, which can have a major impact on our climate.
According to NOAA1, the “tilt” of the earth will give us either more severe weather –warmer summers and colder winters; or less severe weather –cooler summers and warmer winters. The earth is naturally colder than the sun, but thanks to our atmosphere and the greenhouse effect, it’s much warmer here than it is in space (Blue). Our planet is unique because it has the ability to absorb and reflect radiation from the sun and our atmosphere has multiple tiers and contains greenhouse gases.
The greenhouse effect is natural and necessary to sustain life on earth by providing heat to the lower atmosphere. Naturally occurring greenhouse gases include water vapor, carbon dioxide, methane, and nitrous oxide. Under normal atmospheric conditions, they work in harmony to prevent part of the heat emitted by earth from escaping into space (greenhouse gases and climate change. [Video]. In Encyclopedia Britannica) Other greenhouse gases are manufactured, like chlorofluorocarbons (aka CFC’s) used in solvents, refrigerants, and aerosols.
There was a large concern in the 70’s over CFCs breaking down the earth’s ozone layer, the layer of the atmosphere responsible for absorbing the sun’s radiation. When the natural balance of the atmosphere is disrupted, the sun directs more harmful infrared rays towards the ground and amplifies the warming of the planet. The world took notice in the 70’s and the realization was made that CFCs were indeed harming our earth’s fragile ozone layer and in 1985 the Vienna Convention was adopted to formalize and tackle this world-wide issue.
The Montreal Protocol was signed in 1987 further reducing the use and production of CFCs. It is believed that due to these measures, the ozone with heal itself in about 50 years (EPA. gov) The Industrial Revolution (1760-1840) has contributed to a steep rise in man-made global warming. During this period, factories started burning fossil fuels that emit carbon dioxide to fuel automobiles, and provide heat and light for our homes. According to NASA, as of 2009 CO2 levels have risen 38% and Methane levels have risen a staggering 148% since 1750 causing a rise in temperature on the earth’s surface.
Other contributions arise from things we need to survive and sustain a more comfortable life for humans including an increase in agricultural farming and livestock practices, production of oil and natural gas, forest clearing, and decomposing garbage and sewage (Encyclopedia Britannica). Methane is the fastest growing greenhouse gas with cows and livestock accounting for largest amount of human related activity (EPA. gov) Skeptics of global warming will argue that the earth is subject to “cycles” of warming and cooling, or “little ice ages”.
I don’t argue with this, but what I do argue is that mankind is contributing to the speed and intensity of the process. Ice core samples, typically taken from ice sheets and glaciers, show what the temperatures were like and what was present in the atmosphere 800,000 years ago when air was trapped in a bubble in a piece of ice. There has been a direct connection made that shows that increased temperatures go hand-in-hand with increased carbon dioxide in the atmosphere (Ferguson). It wasn’t until 1950 when the carbon in the atmosphere reached 300ppm.
As of April 2012, the global carbon level was 393. 80 and as of April 2013, we are at 396. 72ppm and trending up (Conway & Tans). Is it just a coincidence that since 1850 the 20 warmest years have all occurred since 1981 and the 10 warmest have been in the last 12 years (NOAA)? The signs of global warming are everywhere. Mountain glaciers are retreating and arctic ice is diminishing. Seasonal changes are producing shorter and warmer winters, with earlier arrival of spring temperatures and later onset of winter conditions (Quarles, William).
In addition to the rise in surface temperature, there has been an increase in ocean temperature. A warmer ocean means more extreme weather, plays a significant role in the rise of sea level, and creates a less healthy environment for sea life. Since the Industrial Revolution, the ocean has become more acidic, by as much as 30%, due to carbon absorption and exchange from the atmosphere and has contributed to the bleaching of our coral reefs and could someday change ocean life as we know it (Kolbert). Global warming is in our backyard, to see it one must just turn on the Weather Channel.
In the last 5 years alone, extreme weather caused by air moving over warmer waters had generated some of the most devastating hurricanes in history leaving people homeless or dead and doing billions of dollars in damages. Tornados are ravaging our lands. Deadly heat waves have rocked our nation causing crops to fail. In 2011, Missouri suffered the regions worst one-year drought in history with crop and livestock losses in the billions. Thunderstorms have intensified and cause massive flooding leaving many without power for days forcing people to seek shelter from record high temperatures.
Wildfires blaze out of control across our country due to dry weather and heat destroying homes and leaving our forests bare and blackened. What can we do? We need to take action. There are strategies in place to combat global warming. Carbon sequestration is the process of capturing carbon dioxide from an industrial or energy-related source (e. g. , a power plant or natural gas processing facility), and forcing it at least 800 meters down into an underground reservoir where it is believed pressure from the earth would keep it in a liquid state (EPA). One major downfall with this strategy is that it’s too expensive.
Cost estimates vary widely, but a study from the Global CCS Institute estimates a cost range of $38 to $107 per tonne of captured CO2. Other areas of concern are geologic- can you push carbon dioxide into the ground at this location and is it far enough away from large populations. Ground-water contamination is a fear because it’s possible that, in addition to carbon dioxide, other contaminants (barium, uranium, etc. ) may bubble up with the water. What if the reservoir leaks? What if there’s an earthquake that breaks apart the containment system? Too many questions remain to make this a reliable source of mitigation at this time.
Another strategy is called Geoengineering. This idea aims to fix a man-made problem using man-made solutions (Miller). There are many techniques involved in geoengineering such as cloud brightening, air “scrubbers”, and glacier halting. One technique that I would like to discuss involves putting sulfuric acid and/or salt water into the atmosphere to produce a small haze of reflective particles. This idea arose from the fact that erupting volcanoes shoot sulfur dioxide and other large particles into the sky creating somewhat of an umbrella reflecting sunlight back into space, creating a cooling effect (Miller).
These strategies are more cost effective than trying to reduce carbon emissions, incorporate solar panel, wind energy, carbon sequestration, etc. over the next 40 years (Hayward). Some obstacles that scientists face include figuring out how to get the particles of sulfuric acid into the atmosphere, how to get them to remain there long enough to be effective, and the long-term effects that adding more to the atmosphere may have on our earth and other ecological systems.
A proposed fleet of 80 crafts delivering a million tons of sulfur each year, operating for 20 years has a projected cost of one to two billion dollars (Miller). Unfortunately, like many other mitigation strategies, this too is just to cure a symptom of global warming, not the cause. We are ALL responsible for climate change and I don’t think there is any one “silver bullet” to stop global warming. Per Hugo Chavez at the 2009 United Nations Climate Change Conference in Copenhagen, Denmark, the “destructive model of capitalism” and greed is to blame for global warming.
He went on to say that “if climate was a capitalist bank, the rich governments would have saved it”. I feel that we are going to have to implement many of the existing small strategies over a long period of time in order to cool our planet. Globally, we must all band together and pledge to take action to save our fragile planet. We have to put a price on emissions of CO2 and other greenhouse gases. Some industries that need to be held to more strict standards are the automotive, energy, agricultural and livestock, and companies that are responsible for forest-clearing.
We need to takes steps to reduce our own carbon footprint through education in schools and best practices from those who are getting it done. Maybe we can plant a tree for every one that is cut down. All nations should be held to an equal level of responsibility for dealing with climate change, but the heavy hitters (United States, China, Europe, India, Brazil, etc) need to take charge and lead by example. Just as with our own lives, we only have one Earth. It’s worth saving.
References Bryan, W. (0). Retrieved from http://www. df. org/climate/human-activity-causes-warming 1 (n. d. ) Retrieved from http://www. ncdc. noaa. gov/paleo/milankovitch. html B