- Jacob Ball, PhD student, Epidemiology
As a sub-tropical state, Florida is particularly vulnerable to adverse weather events and other negative products of climate change such as increased incidence of vector-borne diseases and decreased citrus production, which will have major consequences for the health of Floridians and for Florida’s economy.
What is the opinion of Floridians about climate change? And do those opinions vary depending on the wording of the question, “climate change” vs. “global warming”? This study attempted those question using a telephone survey with an embedded experiment.
The questions in this study were added on to the University of Florida Survey Research Center’s monthly Consumer Sentiment Survey. The Center used random digit dialing of possible landline numbers in the state of Florida and asked a short series of questions about their opinions of their personal financial situations and the U.S. economy.
Before the call was made, cases were randomly assigned to contain the phrase “climate change” or “global warming.” Respondents were asked a series of 5 questions about their concern for climate change or global warming, how much they worry about climate change or global warming, the extent to which they agree that scientists believe climate change or global warming is occurring, how personally affected they feel by climate change or global warming, and how likely they are to change their personal behavior due to climate change or global warming.
All of the questions offered respondents an ordinal scale of responses ranging from the most negative option (“not at all likely”, “strongly disagree”) which was assigned a numerical value of 1, to the most positive option (“very likely”, “strongly agree”) which was assigned a numerical value of 4.
These questions were asked each month for a year beginning in December 2009; they were also asked quarterly in 2013. While these questions were always preceded by the exact same questions on consumer issues, other add-on questions varied between months. Nevertheless, we do not feel that the possible variation of preceding questions between months biased the results.
There are no significant differences in the mean age, the proportion of Hispanic ethnicity, marital status or political party affiliation between respondents who were asked about climate change and those who were asked about global warming.
Figure 1 shows a time series of mean responses for the question “How concerned are you about [global warming or climate change]”.
Figure 1: Mean responses of “How concerned are you about [global warming or climate change] over time (YYMM) on a Likert Scale
Generally, concern is uniformly distributed between groups, with the exception of October 2010 and January 2014, where respondents were significantly more concerned about global warming than climate change, with mean differences of -0.22 and -0.36, with p<0.05 and 0.001, respectively. The values between 2.5 and 3 indicate that respondents are more “somewhat concerned” than “not very concerned” about global warming and climate change, and that, qualitatively, this concern has not changed much over time. No mean value reaches 3.0, though April 2010 comes close with a mean concern value of 2.99 for the global warming group.
When asked how much they personally worry about global warming or climate change, the mean responses for both groups generally fluctuate between 2.05 and 2.35, indicating that Floridians, do not personally worry much about the phenomena (Figure 2).
Figure 2: Mean responses of “How much do you personally worry about [global warming or climate change] over time (YYMM) on a Likert Scale
In January of 2014, the mean response for climate change hit below 2.0, indicating that Floridians worry somewhere between “a little” and “not at all” about climate change. In January 2010, respondents worried significantly more about climate change than global warming (p<0.05), while in October of that same year and in January of 2014, respondents worried significantly more about global warming than climate change (p=0.001, and p<0.01, respectively).
Respondents were then asked the extent to which they agree with the statement: “Most scientists believe that [climate change or global warming] is occurring.” Figure 3 shows the time series of the mean responses by age group.
Figure 3: Mean level of agreement with the phrase “most scientists believe that [global warming or climate change] is real” over time (YYMM) on a Likert Scale
Those who were asked about climate change had mean values that consistently surrounded 3, while the respondents asked about global warming had responses that fluctuated between 3.0 and 2.5. In January 2010, respondents who were asked about climate change had significantly higher levels of agreement with the statement than those who were asked about global warming (p<0.05). Similarly, in July, August and October of 2010, and in July of 2013, respondents that were asked about climate change had significantly higher levels of agreement than those asked about global warming (p<0.001, 0.05, 0.05 and 0.05, respectively). The mean difference in responses between those who were asked about climate change versus global warming in July 2010 was 0.46, which is almost double the difference observed in the other months where significant differences were detected between groups.
Figure 4 shows the time series for responses for the question “how likely is it that you will be personally affected by [climate change or global warming]?”
Figure 4: Mean responses of “How likely is it that you will be personally affected by [global warming or climate change] over time (YYMM) on a Likert Scale
Qualitatively, there is no clear trend in agreement for either group of respondents, though between January 2010 and April 2010, respondents asked about global warming consistently felt more likely to be personally affected than those asked about climate change. Additionally, the global warming group’s perceived likelihood to be affected was consistently lower than those in the climate change group between April 2010 and September 2010. The mean responses for both groups fluctuated between approximately 2.3 and 2.7.
Respondents were then asked “How likely are you to make changes in your personal behavior due to [climate change or global warming]?”
Figure 5: Mean responses of “How likely are you to change your personal behavior in response to [global warming or climate change] over time (YYMM) on a Likert Scale
Those who were asked about global warming were significantly more likely to change their behaviors in March 2010, October 2010 and January 2014 (p<0.05, 0.01 and 0.05, respectively). Qualitatively, however, both curves seem to fluctuate around 2.5, indicating that overall people are neutral in their opinions.
In January of 2014, the values for all questions in the climate change group decreased from previous months. Of note, the mean score for “how much do you personally worry?” decreased from 2.3 in August 2013 to 2.2 in October 2013 to less than 2.0 in January 2014. Similarly, the mean score for “how likely are you to be personally affected by climate change?” dropped from above 2.7 in August 2013 to 2.3 in January 2014.
How do our findings compare with studies at the national level?
Schuldt et al  showed that Republicans and Democrats differentially support that “climate change” and “global warming” exist, indicating that framing questions is important and can result in variable responses in different populations. While other studies have examined public perceptions of “(global) climate change” and “global warming” among Americans, to our knowledge, this is the first study that compares perceptions of climate change and global warming among Floridians over time.
Brody et al  used geographic information systems to predict proximity-based vulnerability of respondents to sea level rise, and found that respondents living in 100-year flood plains had lower perceived risk of climate change than those who don’t. They also found that weather and living in a location with a history of natural disasters as documented by damage to property and crops had positive but weak correlations with perceived risk of climate change.
Despite Florida’s increased vulnerability to the effects of climate change, Florida’s state government has gone to great lengths to deny climate change’s existence and its threat to the wellbeing of the state and its citizens A Florida Department of Environmental Protection employee was reportedly placed on administrative leave and mandated to visit a psychiatrist before returning to work because he used the phrase “climate change,” the use of which has been banned by Governor Scott.
 " ‘Global warming’ or ‘climate change’?: Whether the planet is warming depends on question wording,” Jonathon P. Schuldt et al., Public Opinion Quarterly, March 2011; 75(1):115-124.
 “Examining the Relationship Between Physical Vulnerability and Public Perceptions of Global Climate Change in the United States,” Samuel D. Brody et al., Environment and Behavior, January 2008, 40 (1):72-95.
 “On climate change, Florida officials told to speak no evil,” Alexandra Jaffe, CNN, March 9, 2015 (http://www.cnn.com/2015/03/09/politics/florida-officials-climate-change-banned/).
NOTE: The monthly data sets from the Consumer Sentiment Survey were aggregated into a larger dataset. Weights for county and age groups according to the 2010 United States Census statistics were applied in each phase of analysis in order to appropriately control for seasonal fluctuations in population demographics due to snowbirds, as well as general sampling and response biases among age groups and hard-to-reach counties. Data mining and analysis were performed using SAS 9.3. Descriptive statistics for each question were calculated for each month. T-tests and Chi-Squared tests were then performed to assess the significance of the difference of means and relative frequencies of continuous and categorical covariates between the “climate change” group and the “global warming” group for each question. Analysis of variance (ANOVA) with a Tukey correction was run to examine within-group variation within the same month between years and adjust for multiple testing. Results were considered significant with p-values less than 0.05.