Researchers confirm humans are the proverbial frog in the "boiling pot" parable.

From the Proceedings of the National Academy of Sciences of the United States of America. 

Significance

Climate change exposes people to conditions that are historically unusual but that will become increasingly common over time. What kind of weather do people think of as normal or unusual under these changing conditions? We use the volume of social media posts about weather to measure the remarkability of different temperatures and show that remarkability changes rapidly with repeated exposure to unusual temperatures. The reference point for normal conditions appears to be based on weather experienced between 2 and 8 y ago. This rapidly shifting normal baseline means warming noticed by the general public may not be clearly distinguishable from zero over the 21st century, with potential implications for both the acceptance of global warming and public pressure for mitigation policies.

Abstract

The changing global climate is producing increasingly unusual weather relative to preindustrial conditions. In an absolute sense, these changing conditions constitute direct evidence of anthropogenic climate change. However, human evaluation of weather as either normal or abnormal will also be influenced by a range of factors including expectations, memory limitations, and cognitive biases. Here we show that experience of weather in recent years—rather than longer historical periods—determines the climatic baseline against which current weather is evaluated, potentially obscuring public recognition of anthropogenic climate change. We employ variation in decadal trends in temperature at weekly and county resolution over the continental United States, combined with discussion of the weather drawn from over 2 billion social media posts. These data indicate that the remarkability of particular temperatures changes rapidly with repeated exposure. Using sentiment analysis tools, we provide evidence for a “boiling frog” effect: The declining noteworthiness of historically extreme temperatures is not accompanied by a decline in the negative sentiment that they induce, indicating that social normalization of extreme conditions rather than adaptation is driving these results. Using climate model projections we show that, despite large increases in absolute temperature, anomalies relative to our empirically estimated shifting baseline are small and not clearly distinguishable from zero throughout the 21st century.

As CNN writer Jen Christensen notes, it’s not that people are not miserable during heat or bitter cold events, but that the research has found that discussion fades on social media over a six-year period, and that fact might dissuade people from pressuring political leaders to act on climate as memory fades and extreme temperatures begin to feel normal. 

(CNN) The extreme weather that comes with climate change is becoming the new normal, so normal that people aren't talking about it as much -- and that could make them less motivated to take steps to fight global warming, according to new research.

Researchers analyzed more than 2 billion social media posts between 2014 and 2016. What they found was that, when temperatures were unusual for a particular time of year, people would comment on it at first. But if the temperature trend continued and there were unusual temperatures again at that time the following year, people stopped commenting as much.

The authors of the study, published in Monday's Proceedings of the National Academy of Sciences, believe that this is a sign that because of memory limitations and their own expectations and biases, humans may not be the best judges of temperature change. The experience of weather in recent years, rather than over longer historical periods, determines the baseline that people use to evaluate the current weather.

It's the "boiling frog" effect, an urban legend about an experiment that involves putting a frog in a pot of boiling water, where it quickly jumps out. But if it's put in a pot of tepid water on a stove and the heat is gradually increased, the frog will stay in the pot until it dies, because it doesn't feel a difference until it's too late. In other words, people may not recognize the signs of human-caused climate change until it's too late.

Yesterday I shared a diary on critical reporting that big technology and social media have become a major obstacle to the war on climate change. We will have to figure out how to reverse the harm that they are doing to the atmosphere. This is something that we can do.