  While it is well-documented that climate change accepters and deniers have
become increasingly polarized in the United States over time, there has been no
large-scale examination of whether these individuals are prone to changing
their opinions as a result of natural external occurrences. On the
sub-population of Twitter users, we examine whether climate change sentiment
changes in response to five separate natural disasters occurring in the U.S. in
2018. We begin by showing that relevant tweets can be classified with over 75%
accuracy as either accepting or denying climate change when using our
methodology to compensate for limited labeled data; results are robust across
several machine learning models and yield geographic-level results in line with
prior research. We then apply RNNs to conduct a cohort-level analysis showing
that the 2018 hurricanes yielded a statistically significant increase in
average tweet sentiment affirming climate change. However, this effect does not
hold for the 2018 blizzard and wildfires studied, implying that Twitter users'
opinions on climate change are fairly ingrained on this subset of natural
disasters.
