Chapter 2 Flashcards
observations
information detected with the senses - or with equipment that extends our senses.
inferences
conclusions we draw based on observations
atmosphere
blanket of gases that surrounds Earth and other planets
troposphere
region of the atmosphere that starts at ground level and extends upward about 7 miles.
stratosphere
region of the atmosphere that starts at the top of the troposphere and extends up to about 31 miles; contains the ozone layer.
ozone
molecule with 3 oxygen atoms that absorbs UV radiation in the stratosphere.
ultraviolet (UV) radiation
short-wavelength electromagnetic energy emitted by the sun.
science
a body of knowledge (facts and exploration) about the natural world, and the process used to get that knowledge.
empirical evidence
information gathered via observation of physical phenomena
correlation
two things occur together - but it doesn’t necessarily mean that one caused the other.
cause-and-effect relationship
an association between two variables that identifies one (the effect) occurring as a result of or in response to the other (the cause).
scientific method
procedure scientists use to empirically test a hypothesis
hypothesis
a possible explanation for what we have observed that is based on some previous knowledge.
testable
a possible explanation that generates predictions for which empirical evidence can be collected to verify or refute the hypothesis.
prediction
a statement that identifies what is expected to happen in a given situation.
falsifiable
an idea or prediction that can be proved wrong by evidence.
observational study
research that gathers data in a real-world setting without intentionally manipulating any variable
experimental study
research that manipulates a variable in a test group and compares the response to that of a control group that was not exposed to the same variable.
control group
the group in an experimental study that the test group’s results are compared to; ideally, the control group will differ from the test group in only one way.
test group
the group in an experimental study that is manipulated somehow such that it differs from the control group in only one way.
independent variable
the variable in an experiment that the researcher manipulates or changes to see if it produces an effect.
dependent variable
the variable in an experiment that is evaluated to see if it changes due to the conditions of the experiment.
peer-reviewed
researchers submit a report of their work to a group of outside experts who evaluate the study’s design and results of the study to determine whether it is of high-enough quality to publish.
theory
a widely accepted explanation of natural phenomenon that has been extensively and rigorously tested scientifically.
statistics
the mathematical evaluation of experimental data to determine how likely it is that any difference observed is due to the variable being tested.
Montreal Protocol
International treaty that laid out plans to phase out ozone depleting chemicals like CFC.
policy
a formalized plan that addresses a desired outcome or goal.
precautionary principle
acting in a way that leaves a safety margin when the data is uncertain or severe consequences are possible.
adaptive management
plan that allows room for altering strategies as new information comes in or the situation itself changes.
