What is Climate ChangeClimate change, in its straightforward definition, is a shift in both regional and global weather and climate systems produced mainly by increasing levels of carbon dioxide which are a product of fossil fuels. It is a change in average climate patterns over a longer period of time, like years. Though you may be asking, what is the difference between weather and climate? Weather describes day-to-day changes in the atmosphere, like if it is warm, raining, snowing, windy, etc. Climate, on the other hand, describes weather patterns over a long period of time, say a year, in a region. Some examples of climate change are rising sea levels, shrinking glaciers, ice pack melting, changes in blooming seasons, animal migration patterns changing, and more (1).
What causes Climate ChangeClimate change is caused by an excessive amount of Greenhouse Gases that trap heat in our atmosphere that radiates off the Earth’s surface. Greenhouse gases are ‘good’ for our planet because they keep it warm enough for life to survive. Greenhouse gases in Earth’s Atmosphere include; methane, water vapor, nitrous oxide, and the most influential, carbon dioxide. The rise in greenhouse gases is what is causing climate change and its effects. However, too much output of greenhouse gases, like methane, cause warming to accelerate at an unprecedented rate. Main contributors to this overwhelming output are the fossil fuel burning and the commercial and agriculture industries.
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TermsLong term temperature increase of the Earth’s climate over time due to human activities. Increase in the Earth’s global surface temperature. Global warming is one aspect of climate change (2). Atmospheric conditions that happen locally over short periods of time (minutes to days) (2). Long term regional average of temperature, humidity, and rainfall over many seasons, years, or even decades (2). “Coal, crude oil, and natural gas are all considered fossil fuels because they were formed from the fossilized, buried remains of plants and animals that lived millions of years ago. Because of their origins, fossil fuels have a high carbon content” (3). “Greenhouse gases contribute to the greenhouse effect, an effect that occurs when greenhouse gases absorb energy and trap heat in the Earth's surface. Greenhouse gases are essential to keeping our planet warm but too many greenhouse gases concentrated in the atmosphere can increase global temperatures” (4) “When the impact of a predator on its prey's ecology trickles down one more feeding level to affect the density and/or behavior of the prey's prey, ecologists term this interaction a feeding, or trophic cascade” (5). “When CO2 is absorbed by seawater, a series of chemical reactions occur resulting in the increased concentration of hydrogen ions. This increase causes the seawater to become more acidic and causes carbonate ions to be relatively less abundant” (6) |
How do we know Climate Change exists
- “Organisms’ responses to climate change can result in altered species interactions, with cascading effects on communities and ecosystems” (7).
- “climate change can alter the nature of predator effects on decomposition, resulting in unexpected changes in ecosystem function with potentially important global implications” (7).
- “Global warming is linked to a widespread decline in body size, whereas increased flood frequency can amplify nutrient enrichment through enhanced run-off" (8).
- “Resultant flooding can bring about an intensified input of terrestrially derived contaminants such as biocides and nutrients, which imposes stress on aquatic ecosystems” (8).
- “The impacts of individual species loss can therefore cascade through food webs, secondarily affecting species further up or down the food chain” (8).
- “They collect ice cores in many locations around Earth to study regional climate variability and compare and differentiate that variability from global climate signals” (9).
- “The icy layers also hold particles—aerosols such as dust, ash, pollen, trace elements and sea salts—that were in the atmosphere at that time. These particles remain in the ice thousands of years later, providing physical evidence of past global events, such as major volcanic eruptions” (9).
- “Additionally, as the ice compacts over time, tiny bubbles of the atmosphere—including greenhouse gases like carbon dioxide and methane—press inside the ice. These air pocket “fossils” provide samples of what the atmosphere was like when that layer of ice formed" and this helps scientists create a picture of the atmosphere and the amount of greenhouse gases in it at that time (9).
- “Dating back roughly 1.5 million years, these tiny doses of our ancient atmosphere contain "amazingly low" CO2 levels” (10).
Shrinking Ice Sheets
- There are two main ice sheets on Earth and they are in Greenland and Antarctica (11).
- “From 1979 to 2006, summer melt on the ice sheet increased by 30 percent” (11).
- “Since the early twentieth century, with few exceptions, glaciers around the world have been retreating at unprecedented rates. Some scientists attribute this massive glacial retreat to the Industrial Revolution, which began around 1760. In fact, several ice caps, glaciers and ice shelves have disappeared altogether in this century. Many more are retreating so rapidly that they may vanish within a matter of decades" (12).
- “The famed snows of Kilimanjaro have melted more than 80 percent since 1912. Glaciers in the Garhwal Himalaya in India are retreating so fast that researchers believe that most central and eastern Himalayan glaciers could virtually disappear by 2035. Arctic sea ice has thinned significantly over the past half century, and its extent has declined by about 10 percent in the past 30 years. NASA's repeated laser altimeter readings show the edges of Greenland's ice sheet shrinking. Spring freshwater ice breakup in the Northern Hemisphere now occurs nine days earlier than it did 150 years ago, and autumn freeze-up ten days later. Thawing permafrost has caused the ground to subside more than 15 feet (4.6 meters) in parts of Alaska. From the Arctic to Peru, from Switzerland to the equatorial glaciers of Man Jaya in Indonesia, massive ice fields, monstrous glaciers, and sea ice are disappearing, fast” (13).
- “When temperatures rise and ice melts, more water flows to the seas from glaciers and ice caps, and ocean water warms and expands in volume. This combination of effects has played the major role in raising average global sea level between four and eight inches (10 and 20 centimeters) in the past hundred years, according to the Intergovernmental Panel on Climate Change(IPCC)" (13).
- “Oceans are important sinks, or absorption centers, for carbon dioxide, and take up about a third of human-generated CO2” (13).
- “The two major causes of global sea level rise are thermal expansion caused by warming of the ocean (since water expands as it warms) and increased melting of land-based ice, such as glaciers and ice sheets. The oceans are absorbing more than 90 percent of the increased atmospheric heat associated with emissions from human activity”(20).
- “At least one-quarter of the carbon dioxide (CO2) released by burning coal, oil and gas doesn't stay in the air, but instead dissolves into the ocean” (16).
- “Since the beginning of the industrial era, the ocean has absorbed some 525 billion tons of CO2 from the atmosphere, presently around 22 million tons per day" (16).
- Changes the ocean chemistry even though it’s helping take CO2 out of the air (16)
- “so much carbon dioxide is dissolving into the ocean so quickly that this natural buffering hasn’t been able to keep up, resulting in relatively rapidly dropping pH in surface waters. As those surface layers gradually mix into deep water, the entire ocean is affected” (16).
- “Ocean pH has dropped from 8.2 to 8.1 since the industrial revolution, and is expected to fall another 0.3 to 0.4 pH units by the end of the century. A drop in pH of 0.1 might not seem like a lot, but the pH scale, like the Richter scale for measuring earthquakes, is logarithmic. For example, pH 4 is ten times more acidic than pH 5 and 100 times (10 times 10) more acidic than pH 6. If we continue to add carbon dioxide at current rates, seawater pH may drop another 120 percent by the end of this century, to 7.8 or 7.7, creating an ocean more acidic than any seen for the past 20 million years or more” (16).
- “Thermometer records kept over the past century and a half show Earth's average temperature has risen more than 1 degree Fahrenheit (0.9 degrees Celsius)” (21).
Effects
The oceans have absorbed much of this increased heat, with the top 700 meters (about 2,300 feet) of ocean showing warming of more than 0.4 degrees Fahrenheit since 1969 (19). |
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What is at risk?
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Popular Arguments
You may have seen on the news that places around the country and world have unseasonably warm weather, which gives the false prediction that climate change isn’t so bad after all. However, these changes will continue to become more drastic, as we have seen with the raging hurricanes in the southeastern US or the freezing temperatures in the north.
Yes, our climate is constantly changing and has been for thousands of years. The part that is worrisome is that because of the way humans have been using fossil fuels and emitting noxious gases into our atmosphere has caused a detrimental increase in greenhouse gases that is causing our climate to change at an alarming, unnatural rate.
While it is true that we have the power to discover and identify more species, this does not mean it is a result of climate change. These species evolved millions of years ago and have probably just been ‘hiding’ from us. This is why the species extinction rate is skewed; because as species we know go extinct, we are discovering new species. On the other hand, we cannot know how many are going extinct without us ever knowing they existed.
- Fire and eruptions have always been around, it is the human impact of burning fossil fuels that seems to enhance other effects like natural burning/fires (18).
- “To face the challenges ahead, scientists recommend we increase efforts to restore our forests ability to store carbon as a buffer against climate change and fire" (18).