Boulder Boiling? Being Green won’t Stop Boulder from Feeling the Effects of Climate Change
Boulder, Colorado has long been a pillar for eco-awareness and environmentalism and was even ranked as the #1 city for sustainability startups per capita in 2022. Across the startup sub-industries of Renewable Energy, Environmental Engineering, and Recycling and Pollution Control Boulder ranks among the top 5 of all U.S. cities, demonstrating a strong economic interest in combating climate change. The city also has a complex climate action plan which includes efforts such as reducing harmful emissions and removing carbon dioxide from the environment. Despite all the attention paid to environmental issues in Boulder both by government entities and industry innovators, there are still plenty who deny climate change, like Joe O’Dea, who ran in 2022 to represent Colorado in the U.S. Senate and 139 members of the 117th Congress. Given the persistent efforts of some to refute the existence of climate change, as well as recent extreme weather-related events like the Marshall Fire that took place in Boulder County, it is worth asking whether the climate in Boulder is really changing.
To answer this question I examined weather data for 2010–2021, taken from NOAA’s National Center for Environmental Information. The dataset includes daily measurements of temperature and windspeeds from NOAA’s Boulder Weather station. Unfortunately, data on precipitation was not available from this source. The United States Environmental Protection Agency lists average, seasonal, and high and low temperatures as important indicators of climate change. So how have weather trends in Boulder changed over the past decade, and what do these trends tell us?
Although the trend is not linear, the data shows that average annual temperatures in Boulder have increased since 2010. In 2010 the mean daily temperature was 52.85 degrees Fahrenheit, and in 2021 that figure was 53.51 degrees. In fact, 2019, 2020, and 2021 all have average annual temperatures over 53 degrees, suggesting that temperatures may remain at this higher level. This may seem like an insignificant increase, but it also occurred over a relatively short period of time. Examining historical data from NOAA, average Boulder temperatures in the 1920s were between 48 and 51 degrees Fahrenheit for nine out of ten years in the decade. Only 100 years later average temperatures are several degrees higher and appear to be rising still, indicating that the pace of climate change in Boulder may be accelerating quickly.
Further examining temperature data, I was curious if increases in temperature were particularly evident in certain seasons since the EPA identifies average temperature increases as especially high in winter and lower in the summer. The Boulder data was somewhat inconsistent in showing change in temperatures seasonally; the average January temperature in 2010 was 34.99 degrees, and in 2021 this figure was 35.07. The 2010 average July temperature was 73.35 degrees while in 2021 it was 75.21 degrees. These figures alone seem to indicate seasonal temperature increase over time, however, the fluctuation in seasonal temperatures from year to year within the 2010s makes it difficult to declare a trend. Data dating further back would be necessary to determine whether the national trend of winter temps increasing by 3 degrees since 1986 holds true in Boulder.
Finally, I was curious whether the number of days with very high temperatures in Boulder has gone up since 2010 since the EPA states that “Record-setting daily high temperatures have become more common than record lows.” The data revealed that four of Boulder’s five hottest years since 2010 have occurred since 2016, with 2012 (a nationally very hot year) being the only exception. 2016, 2018, 2020, and 2021 all had 37 or more days where temperatures reached 90 degrees in Boulder, indicating that very hot days may be becoming more frequent.
Although data on precipitation was not available, higher temperatures increase evaporation and worsen drought conditions, so Boulder is likely to continue experiencing long dry periods, which of course bring extreme events like wildfires. As an environmentally conscious community, Boulder may not be to blame for its changing weather patterns, but the trends of increasing temperatures are becoming more evident and extreme as time goes on, and Boulder is not immune to these negative effects. The eco-conscious Boulder community should consider focusing more efforts on climate change resilience in addition to climate change mitigation, as well as continue to vote against politicians like climate-denier Joe O’Dea, who refuse to acknowledge the proof of climate change in their own communities.
