During spring break of my senior year of high school, my dad and I planned a trip to Iceland to see a solar eclipse. However, another activity that we were also able to hike up a glacier. This particular event turned into more of an educational experience. Our tour guide and his co-workers worked on this glacier for many years. In the past quarter century, they placed a marker on how far back the glacier was receding from the coastline. The guide explained that the majority of the glaciers in Iceland were also decreasing. As it turns out, this was not an isolated occurrence, but rather happened across the world. He firmly believes that the reasoning for this recession was global warming. Our guide informed us that the glacier was melting at an increasing rate and how the majority of the nearby glaciers were experiencing the same phenomenon. 

Now, fast forward to 2016, when the head of the EPA, Scott Pruitt, said, “I think that measuring with precision human activity on the climate is something very challenging to do and there’s considerable disagreement about the degree of impact. So no, I would not agree that [carbon dioxide is] the primary contributor to the global warming that we see” (Carroll, 2017).  It seems that Pruitt’s comment casts doubt on the validity of man’s contribution to global warming. As opposed to the tour guide’s significant concern about the future in regards to global warming, Pruitt seemed to have a more cavalier attitude.  However, the problem with both Pruitt’s and our tour guide’s opinion is that neither are experts on the subject of climate change.

It is has been well established from multiple sources that earth’s climate has demonstrated significant shifts over geological time. Just in the last 700,000 years, there have been seven cycles of glacier evacuations and formations. These were clearly not influenced by human activity because it preceded human society (Saftel, 2017). Using thermometers, people have been recording the surface temperature of the earth for the past 150 years. The data shows a dramatic increase in the surface temperature beginning around 1960 and continuing through the present day. Richard Wolfson, a professor at Milbury College, claims, “reconstructing climate history before the last 150 years requires the use of ‘fingerprints’ which includes the size of tree rings, sentiment patterns from lakes, and more sophisticated techniques using radioisotopes” (Wolfson, 2007).  Using similar techniques, carbon dioxide concentrations demonstrate a similar upstroke beginning with industrial revolution approximately 150 years ago (Wolfson, 2007). Alina Bradford, a climate scientist, claims, “there were about 280 parts per million of CO₂ in the atmosphere, and during most of the past 800,000 years” (Bradford, 2015).  Presently, it is estimated that carbon dioxide is at 350 parts per million (Wolfson, 2007). This also stands out as a deviation from the background natural variations.  These upstrokes are not accounted for by our most accurate climate models. There is 95 percent probability, or greater, that the current heat trends are a result of human activity (Shaftel, 2017). According to the Intergovernmental Panel on Climate change, the panel states, “Scientific evidence for warming of the climate system is unequivocal” (Shaftel, 2017). NASA climate researchers have documented evidence that proves that the Earth’s climate is changing.  Site this or take it out.

For clarification, the greenhouse effect and “manmade”/anthropogenic climate change are not equivalent (Wolfson, 2007). The greenhouse effect is a natural phenomenon that explains why the earth is approximately 60 degrees Fahrenheit warmer than what would be predicted by simple models (Wolfson, 2007). The earth receives the majority of its heat primarily from the sun in the form of visible light (Wolfson, 2007). This heat source passes through the atmosphere with little interaction and does not directly heat the atmosphere. However, once the earth heats up it will also radiate energy, but this is primarily in an infrared form (Wolfson, 2007). The infrared light is absorbed by the greenhouse gasses (Wolfson, 2007). When these gasses readmit the heat half of it comes back towards the earth (Wolfson, 2007). This is like placing a blanket around the earth and slowing losing the Earth’s infrared heat (Wolfson, 2007). The naturally occurring greenhouse gasses are water and carbon dioxide (Wolfson, 2007).  It seems this is an accurate model of Earth as Mars, which has no atmosphere, has a temperature very closely predicted by this simple example (Wolfson, 2007).  Alternatively, Venus, which has a very dense carbon dioxide concentration is 100s of degrees warmer than the predicted model (Wolfson, 2007).

Burning of fossil fuels adds carbon dioxide to the atmosphere which is believed to increase the natural greenhouse effect.  This conclusion is supported by multiple lines of evidence.  First, the concentration of carbon dioxide in the atmosphere is 40% higher than pre-industrial revolution times (Wolfson, 2007).  Since fossil fuels are a commodity, the amount burned can be reasonably estimated (Wolfson, 2007). The amount of carbon dioxide to be released is in line with the 40% increase (Wolfson, 2007). Additionally, fossil fuels have been buried for millions of years.  Because of this, they are depleted in carbon 14 (Wolfson, 2007).  This reduction in the carbon 14 percentage is also reflected in Earth’s present atmosphere.  There are additional lines of evidence from temperatures from mine shafts and the outer atmosphere which point to the surface of the earth as being the primary site for an increase in temperature.  This also would be expected from the greenhouse effect. As an aside, the greenhouse effect is a misnomer.  Greenhouses work by preventing loss of heat from convection, not radiation.  

As previously stated that both water and carbon dioxide play a role in the natural greenhouse effect.  However, it is theorized that the human-made carbon dioxide is the reason for anthropogenic climate change.  The reasoning for this is complex.  The bottom line is that the water is added to the atmosphere which is recycled out in approximately five days through the water cycle.  However, carbon dioxide has a more complex cycle.  It is estimated that the carbon that is added to the cycle can persist for 1000s of years.  It should be remembered that the fossil fuels that we burn for society's energy needs have been trapped outside the cycle for millions of years.  Humans are releasing this trapped carbon dioxide since the industrial revolution. Present data estimates that humans are adding seven gigatons of carbon into the atmosphere yearly.  There are additional two gigatons that are effectively added by deforestation.  It should be emphasized that this carbon will remain in the cycle for 1000s of years and will accumulate in its effect. 

Over 96% of climate scientists are convinced that the present warming trend is primarily, although not entirely, related to anthropogenic causes.  Scientists believe that they have already seen measurable effects.  For one thing, the oceans are demonstrating an increase in temperature of approximately 0.3 degrees Fahrenheit since 1969 (Shaftel 2017).  The carbon dioxide is also causing a rise in the acidity of the oceans.  This growth has been causing a disruption in some ecosystems. Most profound is a story from the Washington Post in 2017 detailing the bleaching effect of the Great Barrier Reef off the coast of Australia (Mooney, 2017).  This Reef is the largest living system on the earth and can be seen from space.  However, significant portions are now dead due to the acidic pH (Mooney, 2017).  This is being directly attributed to global warming and the ocean acidification (Mooney, 2017). 

Not only are glaciers receding worldwide but significant portions of the polar ice caps are receding as well. This is in part an explanation for the rise in sea levels. However, the rising temperature also expands water causing the oceans to rise. It has been estimated that species on average are migrating 10 km away from the equator every ten years. In similar fashion, mountain species are elevating their range 10 meters higher every ten years. These are the species that can migrate. It is believed that one of the difficulties for ecological systems is the rate that the changes are occurring. Typically, biotic factors have thousands of years to adjust. For most, species evolution cannot keep pace with rapid changes. It does appear that the rate of extinction has been significantly accelerating in the very recent past.  This acceleration is theorized to be secondary to human activity (Kolbert, 2015).  However, this extends well beyond just the effects of global warming.  Geological epochs are traditionally named for the primary factor responsible for the characteristic of that era.  It has been suggested that this period will be called anthropocene (Kolbert, 2015). 

The science of Pruitt’s logic is extremely misleading. Meaning, that the natural greenhouse effect is secondary to both water and carbon dioxide with water being the first player. So the individual facts he states are factual. However, in the context of global warming, they amount to subterfuge. Carbon dioxide is far and away the primary contributor to global warming. With his denouement being incorrect, it means that people are fed false information which leads to doubt in society about the importance of climate change..  The average human being utilizes energy at a rate of 2000 watts to sustain a modern lifestyle. (The human body uses energy at the rate of 100 watts.) This 2000 watt value varies greatly according to country and lifestyle. For instance, the average American/Canadian utilizes energy at ten times the rate. The average European at five times the rate. As globalization occurs the average 2000 watt value will increase.  The IPCC  has generated models to estimate carbon output depending on different strategies.  They have estimated that if we continue strong reliance on fossil fuels within the next 100-200 years, we could be adding as much as 25-30 gigatons of carbon per year. Although difficult to estimate this could raise the temperature 5-7 degrees. It should be pointed out that the average temperature change between and ice age and an interglacial period is approximately 6 degrees. These models only take into direct account effects. Tipping point events cannot be predicted in these models. This would include such things as the sliding of a significant portion of the Antarctic ice sheet into the ocean. This could instantaneously raise the sea level by four feet.  

The present administration seems to be taking a path that downplays human-made global warming.  Recently the Trump administration recently proposed deep cuts for the EPA singling out climate programs.  This included funding for the Oceanic and Atmospheric Administration which monitors the sea and sky.  There is significant concern that there will be limitations put on the exchange of data between climate scientists working for the federal government.  This will hinder progress on climate science.

Thus, in conclusion, climate change needs to be discussed at a worldwide before anymore damage is already caused. This planet, like the coral reefs and the oceans, have already seen horrible damage to them within the past years. The damages of these ecosystems will cause a chain reaction. For example, there was a recent event in Guam where a tidal flooded the island and killed citizens. Normally, the coral reef located on the outskirts of the island would protect the island by breaking the tidal waves. However, since the reefs died, due to the pH becoming more acidic, the wave was not stopped and it hit the territory. This caused physically damage; however, with the coral reef dying, it causes economically damage too. Because Guam is a fishing nation, it relies on that coral reef to keep the fish. But, the fish left after the coral died, so the country went into a depression state. Now, imagine this happening worldwide with countries that actually rely on fishing. And it’s a possibility when our current EPA president completely negates human activity. That’s why, it needs to be open discussion with worldwide leaders because climate change will and has affected our world.  
