ACT (Enhanced)ScienceHard
A climatologist is analyzing historical temperature data for a specific region. They observe a strong correlation between periods of increased volcanic activity and a decrease in global average temperatures. Based on this observation, the climatologist infers that volcanic eruptions can contribute to short-term global cooling. Which of the following is an underlying assumption made by the climatologist in drawing this inference?
- AFuture volcanic eruptions will have the exact same cooling effect.
- BThe historical temperature data is perfectly accurate and complete.
- CVolcanic activity is the sole cause of global temperature fluctuations.
- DThe decrease in temperature is not due to other independent climatic factors occurring simultaneously.
Show answer & explanationAnswer & explanation
Correct answer: D. The decrease in temperature is not due to other independent climatic factors occurring simultaneously.
For the inference to be valid, the climatologist must assume that the observed cooling is primarily due to volcanic activity and not merely a coincidence with other unrelated climatic events or cycles. This is the essence of isolating the cause-and-effect relationship.
Why the other options are wrong
- A. The inference is about past contribution, not a precise prediction for future events, which could be influenced by many variables.
- B. While accuracy is important, the inference can still be drawn with some data imperfections, as long as the correlation holds. The assumption is about causation, not perfect data.
- C. The inference states 'can contribute,' not 'is the sole cause,' so this is too strong an assumption.
Scientific Inference
A conclusion reached on the basis of evidence and reasoning, often involving assumptions about underlying mechanisms.
- Goes beyond direct observation.
- Relies on logical reasoning and existing knowledge.
- Can be strengthened or weakened by further evidence.
Memory trick: Inference: 'I N-fer' what's happening based on what I see.