Carbon Dioxide is the second most common greenhouse gas in the atmosphere after water vapor, and in terms of manmade greenhouse gases, it is number 1. Reducing humans carbon dioxide pollution is the simplest and most effective way to slow down the effects of manmade climate change. Despite their reputation, greenhouse gases are necessary for life on earth. They work by trapping energy emitted by the sun in the earth’s atmosphere, allowing for warm atmospheric temperature. The problem arises when the natural balance of greenhouse gases is disrupted. For hundreds of thousands of years before the advent of modern technology, greenhouse gas emissions stayed roughly equal, moving up and down slightly but never jumping or dropping hugely. The introduction of the combustion engine and burning coal and fossil fuels to generate energy upset this balance, introducing more greenhouse gases into the atmosphere.

smokestack

Smokestacks

Many possible solutions to the problem of carbon emissions have been, and some have been put into place. Carbon Dioxide scrubber technology is one of the most logical and practical, and in some instances has already been implemented. Smokestack scrubbers, which can help to clean the smoke emitted by power plant, are already in use in some places, and the technology is growing fast. The idea behind using the scrubbers on smokestacks is to limit the further damage to the environment by reducing the pollution at the source, significantly limiting the amount of CO2 and other pollutants released by the plants it is used on. This same technology could theoretically be applied to vehicles, although it would have to be scaled down significantly in both size and price to work. The more ambitious application of this technology involves physically removing CO2 that is already in the atmosphere.

Conceptual design of an atmospheric carbon scrubber

Conceptual design of an atmospheric carbon scrubber

This proposition is far more difficult than removing CO2 from smokestacks, because the percentage of CO2 in the air is only 0.04%, meaning that to remove significant amounts, you would need a much larger scale operation to be effective. This technology is far more revolutionary, as it actually allows us to reverse the effects of global warming and lower the greenhouse gas levels in the atmosphere. Almost all other proposed solutions to the problem involve slowing down or stopping our emissions, but actually removing CO2 allows us to reverse the effects of climate change.

http://www.bostonglobe.com/business/2015/02/02/mit-researchers-developing-better-way-scrub-smokestack-pollution/FDvpDH4TszfMy7Rsicp1FK/story.html

http://www.physicalgeography.net/fundamentals/7a.html

http://www.theguardian.com/environment/2011/feb/04/man-made-greenhouse-gases

http://www.epa.gov/climatechange/science/indicators/ghg/ghg-concentrations.html

http://www.power-eng.com/articles/2013/03/us-coal-fired-power-plants-invested-more-than-30bn-on-scrubbers-.html

http://phys.org/news141915261.html

The Evolution of Solar Energy

Almost all non-nuclear energy on earth comes from the sun in one way or another. Gasoline and other fossil fuels come from plant matter, which gains its energy from the sun. Hydroelectric and wind power both come from the sun through complex processes. Direct and conscious of manipulation of solar energy has been around for a very long time, at least since the time of Socrates, who said

“In houses that look toward the south, the sun penetrates the portico in winter, while in summer the path of the sun is right over our heads and above the roof so that there is shade”

Humans have been trying to figure out how to improve our efficiency for a very long time, and passive solar design is one of the first ways that we actively made use of the sun. Passive solar energy is when a building is constructed in a way that maximizes the possible heat from the sun. It is one of the earliest ways that humans made use of the suns energy directly. One of the first uses of active solar power was a steam-powered engine that powered a water pump. The concept of solar radiation powering a steam engine translated into a steam engine powering a turbine, which paved the way for industrial solar-powered electricity generation. The concept of solar powered steam generators is one that is still used to this day.

solar-energy

The next innovation in solar power was photovoltaic cells. Photovoltaic cells are what we usually refer to as solar cells. Photovoltaic cells can be put almost anywhere sunny, and are far more practical for private use than steam generators. Photovoltaic are now a major contributor to the solar industry. Today, solar energy is growing faster than all nonrenewable energy sources combined, which bodes well for the future of clean energy. 

Tidal Energy: Nature’s Unexploited Source of Renewable Energy

Tidal energy has massive opportunity as a renewable source of energy, but is almost never used. There are multiple types of tidal generators, but most harness the movement of water during tides to turn a turbine, which turns a generator, producing electricity

tidepower-1

Diagram illustrating a tidal power plant

 

 

Tidal power has several advantages over other sources of power. It is completely renewable, because as long as there are tides, there will be an abundant source of energy. It is more reliable than both solar and wind power, and unlike hydroelectric dams, it has a large amount of possible sites. Tidal power plants also have some major disadvantages. In terms of environmental impact, tidal power plants are not perfect. While they are renewable energy sources, and produce no pollution, Tidal plants could affect the environment in a manner very similar to hydroelectric dams and wind farms. Instead of polluting, they physically endanger animals, and their presence can get in the way of migration routes and breeding grounds. As of now, Tidal plants are expensive, and many oppose their construction on aesthetic grounds.

62 megawatt power plant in France

62 megawatt power plant in France

Despite the positives, today there are only 7 tidal power plants worldwide, and none in the united states. Despite the constant talk about the necessity of finding green alternatives to traditional power, there has been little to no interest in this technology. While it may not be a silver bullet, tidal power is far to promising to be ignored, as it has been.

 

 

 

Sources:

http://www.oceanenergycouncil.com/ocean-energy/tidal-energy/

http://www.darvill.clara.net/altenerg/tidal.htm

http://education.nationalgeographic.com/education/encyclopedia/tidal-energy/?ar_a=1

http://oilprice.com/Alternative-Energy/Tidal-Energy/How-Does-Tidal-Energy-Work.html

http://en.wikipedia.org/wiki/List_of_tidal_power_stations

 

How Much Do We Know About Fracking?

Many people have heard of fracking and the controversy that surrounds it, but few know what it actually means, or what the environmental cost is. Fracking is a word that has a lot of politics behind it, and triggers a lot of immediate reactions, but many people do not even understand what it is.

Natural gas is a nonrenewable fossil fuel, but burns cleaner than coal or petroleum. Natural gas is used in many domestic and commercial applications. It is composed of simple hydrocarbons, mostly made up of methane. It is traditionally mined from gas fields using wells, but a large amount of gas trapped in shale formations cannot be mined in this way. Fracking allows that gas to be mined. Fracking, or hydraulic fracturing, works by injecting a high-pressure mixture of water, chemicals and proppant (solid material used to keep fractures open) into the shale, causing the shale to fracture and release the gas.

Fracking is a new way of mining natural gas, and there has been little time to see what long term negative effects it has on the environment. There are several specific concerns about fracking’s environmental impact. Fracking uses an estimated 70 to 140 billion gallons of water each year. This raises concerns about the impact on drinking water resources and the effect on aquatic ecosystems. Proppant used in the fracking, usually silicone based sand, needs to be mined, and can contaminate groundwater. Various chemicals are also added to the fracking fluid, some of which have very serious health consequences. Pollution from the fracking fluid can seep into drinking water reserves and aquatic ecosystems, threatening both natural and human health. The concerns about fracking are not just theoretical. There are multiple examples of spills like this occurring. In addition to the spills, there is a worrying lack of accountability, with gas companies failing to report the spills to the government.

Natural gas may be the cleanest burning fossil fuel, but if mining for it involves fracking, the trade offs may not be worth it. We still do not know the full potential to cause damage to the environment that fracking has, but that has not stopped numerous companies from setting up fracking sites. There over 2 million hydraulically fractured wells in the U.S., and around 95% of new sites use the procedure. To continue this trend of using technology without any consideration for its environmental impact is irresponsible and near-sighted.

 

 

Sources:

http://www.earthworksaction.org/issues/detail/hydraulic_fracturing_101

http://www.epa.gov/cleanenergy/energy-and-you/affect/natural-gas.html

http://www.csg.org/pubs/capitolideas/May_June_2012/fracking101.aspx

http://www.greenpeace.org/usa/en/campaigns/global-warming-and-energy/The-Problem/fracking/

Nuclear Energy

A fire burns at the Fukushima nuclear plant in Japan.

Nuclear energy is one of the most controversial and misunderstood sources of energy in the world, and it may very well be the solution to the energy crisis. When most people hear nuclear energy, their mind often automatically goes to doomsday scenarios or public disasters such as Fukushima or Chernobyl. Many people view nuclear energy as dangerous and unpredictable, but in fact, it may have actually prevented 1.8 million deaths.

When a nuclear reactor fails, it does so in spectacular fashion, and necessitates a massive clean up effort. Nuclear disasters are few and far between, but when they do occur, the media circus surrounding them ensures that a huge amount of people can see the disaster, and that many people will form an opinion on nuclear. While nuclear energy does have some very serious drawbacks, there is no energy source without some cost. The problem with more traditional forms of energy is that their production’s costs are often hidden. The pollution caused by coal and natural gas plants accounts for a massive amount of disease and resulting death worldwide, but those plants rarely have massive meltdowns, and hence get less negative media attention.

From what I have written in this blog so far, it may seem that I think that nuclear energy is a perfect solution. It is not. While it may cause less death and disease than other forms of energy, and it does not contribute to climate change, it has other risks. While it may appear that nuclear energy is a completely renewable and unlimited source of energy, this is not completely true. Uranium is still expensive to obtain, and mining generally has negative consequences for the environment. An even more pressing issue is the problem of disposal of nuclear waste. Nuclear waste is radioactive, meaning that it must be contained safely, and it degrades very slowly, meaning that any attempt at storage must be extremely durable and stable. While it does have a lower affect on the environment than other forms of energy, the reactors that produce nuclear energy pose the threat of catastrophic meltdown such as the recent Fukushima accident. Disasters like this threaten to expose entire cities to dangerous radiation, and can cost millions to clean up. In the end, Nuclear energy is a promising but imperfect solution, and it may be our best option looking forward.

Sources:

http://pubs.acs.org/doi/ipdf/10.1021/es3051197

http://blogs.scientificamerican.com/the-curious-wavefunction/2013/04/02/nuclear-power-may-have-saved-1-8-million-lives-otherwise-lost-to-fossil-fuels-may-save-up-to-7-million-more/

Global Atmospheric Circulation and Pollution

While it may seem that our atmosphere is random and chaotic, on a global scale, the movement of earth’s atmosphere is actually very predictable, and follows predetermined patterns. There are 3 cells in each hemisphere, the Hadley cell, the Ferrel cell and the Polar cell. These cells move air vertically along the longitude lines, and are caused when warmer air rises and moves towards the cooler poles, then drops back down and moves back towards the equator, slowly cycling in a oval shape. Along the latitude lines are wind currents that rotate around the earth. These currents are caused by the north-south motion of air in the Hadley, Ferrel and Polar cells interacting with the earth’s spinning motion.

Diagram showing global air currents

These currents effect global weather patterns and temperature in a multitude of ways, but they can also have some unexpected consequences. More specifically, they can carry air pollution from one side of the globe to another. This means that even though a specific area produces very little pollution, it can still be affected by pollution from across the world. This situation is not merely hypothetical, and it is one of the reasons that pollution is a global problem, rather than simply a local one.imgres

Pollutants such as mercury have been found in the U.S., providing physical proof that this phenomena is occurring. This raises many concerns, as it is difficult to compel a country to limit its emissions if the country is not inclined to. It also causes a distressing paradox: if a county cannot eliminate pollution within its borders by eliminating pollution, what incentive is there for that country to try to clean up its emissions. This leads to a downward spiral of countries unwilling to spend money to control pollution. While this may seem unavoidable, with strong leadership from the developed world, it can be avoided. The problem today is that the environment seems to be at the back of policy makers’ minds. If the major industrial countries were to put real political and economic effort into solving this issue, we could contain pollution without any serious difficulties. Sadly, this does not seem likely to happen until pollution becomes too serious to ignore. By that time, it may be too late.

Sources:

http://www.oregonlive.com/environment/index.ssf/2008/04/chinas_mercury_flushes_into_or.html

http://thinkprogress.org/climate/2014/04/15/3426934/air-pollution-changing-weather-patterns/

http://daily.sightline.org/2014/05/20/blowback-chinas-cross-pacific-pollution/

Farming and the Environment

There are about 7 billion people in the world currently, and that number is projected to rise to about 8.9 billion by 2050. Assuming that each person consumes 1200 calories per day, this means that each year, the world consumes about 3066 trillion calories. Producing this massive amount of food is a problem that is not going away, and neither are the problems created by the growing of this food. The main problem with fertilizer is that it is not all absorbed by the farmland that it is intended for, causing runoff that can pollute natural bodies of water with excess nitrogen. In lower concentrations, nitrogen is actually necessary to sustain life within an ecosystem. When there is an excess of nitrogen, however, the system becomes overloaded with algae, which can cause problems.

A sign warns swimmers about an algal bloom. This is an example of one of the negative repercussions that fertilizers can have.

A sign warns swimmers about an algal bloom. This is an example of one of the negative repercussions that fertilizers can have.

The algae can be toxic, poisoning animals that consume it, but this is not the most common result. The vast majority of times, fertilizer runoff causes a massive amount of algal growth, leading to mass death and decomposition of the algae. This process of decomposition removes oxygen from the water, making the area survivable for other organisms in the ecosystems. This effect can be very damaging to ecosystems, and it can be very difficult for them to recover their biodiversity. Non-organic fertilizers are often used in conjunction with chemical pesticides/herbicides that can contaminate and pollute clean bodies of water

An algal bloom near Qingdao china.

An algal bloom near Qingdao china. Blooms such as these are often caused by fertilizer runoff.

. Despite all of these problems, use of artificial fertilizer and pesticides/herbicides is still an extremely common practice. Why? Very simply, because other methods are not efficient enough. There are 7 billion people to feed, and not producing enough food is not an option. Crop rotation is nice in theory, but for a farm attempting to produce the maximum amount of possible food, it does not work, because it does not allow the farm to produce the same product on the same field every year. Pesticides/herbicides and fertilizer can be detrimental to the environmental, but for many farmers, they are a necessary evil. In an ideal world, we would be able to produce all the food we need without any ecological harm, but sadly, it is not economical to run a large-scale farm without using chemicals, and hence nobody does it. There are, however, many ideas about improving are farms. Improved laws and incentives aimed at increasing the sustainability of large-scale farms are one option. As awareness of the importance of protecting the environment has risen, so have technological innovations such as the N-Sensor a sensor that helps farmers to reduce nitrogen runoff, protecting the environment as well as saving money. Innovations and ideas such as this are the best way to combat the problems caused by large-scale farming.

 

Sources:

http://www.scientificamerican.com/article/fertilizer-runoff-overwhelms-streams/

http://www.un.org/esa/population/publications/longrange2/WorldPop2300final.pdf

http://www.scientificamerican.com/article/how-fertilizers-harm-earth/

http://www.noaa.gov/features/earthobs_0508/algal.html

http://www.yara.co.uk/crop-nutrition/Tools-and-Services/n-sensor/