• Scientific Data:
- Compared to the yearly average of 6.5 million square kilometers between 1979 and 2010 for September, the Arctic sea ice shrank below 4 million square kilometers in September 2012, which is lower than any minimum value observed in the last three decades.
(European Environmental Agency, “The Melting Arctic")
•• Why? •• This excerpt uses scientific data to inform the reader about an event that took place
• Expert Opinion:
- According to Morten Olsen, chair of a recent Arctic council assessment of changes on Arctic snow-and ice-conditions, "Changes in the climate and cryosphere risk fundamentally altering the Arctic ecosystems."
(European Environmental Agency, “The Melting Arctic")
•• Why? •• This excerpt uses a quote from a "high-ranking official" in order to show that something is true, because who would you pick: a student in an AP class or a well-known scientist. I would take the latter.
• Association:
- Sip a cup of Turbo Brown to taste the liberating power of flying through your day's work like a cruising jet.
•• Why? •• This excerpt uses a sentence (in this case, a description), and then ASSOCIATES it with you. For example, "If you don't buy these shoes, then you'll not be cool like the other kids who are." That statement makes you want to buy new shoes in order to be like the other kids. Who knows? Maybe you need new shoes anyway...
• Emotional Appeal:
- If we don't step up our efforts, the melodious songs of these beautiful birds might be silenced forever.
•• Why? •• This excerpt uses a "call-to-action" in order to convey a message to you that you need to do something about it.
All of this is my reasoning. I hope this LONG and THOROUGH answer helps you with your question.