Climate in the Heartland: Historical Data and Future Projections for the Heartland Regional Network
Climate in the Heartland describes projected climate change impacts for five municipalities: Iowa City, Iowa; Columbia, Missouri; Lincoln, Nebraska; Lawrence, Kansas; and Oklahoma City, Oklahoma. The analysis finds that annual temperatures are projected to increase substantially for each municipality. The average temperature in coming decades will be higher than extremes that have recently occurred on average only once per decade. Additionally, frosts are projected to start later and end earlier for all five municipalities. Spring precipitation is expected to increase in all municipalities except Oklahoma City.
For the climate analysis, the researchers averaged nine global climate models (GCMs) in order to identify trends that were present across a range of models and scenarios. Additionally, the researchers used a technique known as downscaling to see projections at a finer scale. The report analyzes future annual and seasonal temperature, annual and seasonal precipitation, last spring frost, first fall frost, heat waves, cold waves, heavy rainfall, snowstorms, and thaw/freeze cycles. The report notes that these conditions are important for municipalities planning for general climate conditions, parks and recreation, employees working outdoors, insect vectors, energy demand, public health, stormwater management, floodplain planning, emergency response, infrastructure design, snow and ice management, public safety, electricity and phone service outages, street repair, parks and recreation, and urban forest management.
The report provides a summary of the similarities across the region, and more detailed information about the projections for each city. It finds:
- Iowa City, Iowa has already experienced increased temperatures, and that trend is likely to accelerate going forward. Iowa City is also likely to experience more spring and summer precipitation that will impact the growing season.
- Columbia, Missouri has already experienced increased temperatures, increased dew point temperatures, and increased frequency of heavy rainfall. Columbia’s annual temperature is projected to increase so much that the 30-year average temperature in the future will be well above the hottest years in the normal range throughout history. Spring precipitation is also expected to increase substantially, while summer precipitation is projected to decrease. These changes will impact Columbia’s growing season and infrastructure.
- Lincoln, Nebraska has already experienced increased temperatures, and that trend is predicted to continue. Lincoln has also experienced fewer thaw/freeze cycles. Given that Lincoln’s water supply is sourced from areas around the Platte River, which has headwaters in the Rocky Mountains, it is important to consider changes going on outside of the Lincoln area.
- Lawrence, Kansas has already experience summer warming and warmer and wetter spring seasons. Temperatures are expected to increase substantially in recent years. Milder springs can cause vegetation to break dormancy early at a time when it is more vulnerable to freeze damage.
- Oklahoma City, Oklahoma has already experienced warmer and wetter winters, and warmer springs and summers. Rainfall has been increasingly volatile. Oklahoma City is likely to experience increasing temperatures and shorter frost periods.
This report was produced through a partnership between the sustainability directors in each of the five cities that are part of the Heartland Regional Network of the Urban Sustainability Directors Network (USDN). The five cities were also assisted by state climatologists, climate scientists, and consultants.
Publication Date: September 2015
Authors or Affiliated Users:
- Christopher J. Anderson
- Jennifer Gooden
- Patrick E. Guinan
- Mary Knapp
- Gary McManus
- Martha D. Shulski
- Air temperature
- Heat waves
- Precipitation changes