FAQs

Structures such as buildings, roads, and other infrastructure absorb and re-emit the sun’s heat more than natural landscapes such as forests and water bodies. Urban areas, where these structures are highly concentrated and greenery is limited, become “islands” of higher temperatures relative to outlying areas. These pockets of heat are referred to as “heat islands.” Heat islands can form under a variety of conditions, including during the day or night, in small or large cities, in suburban areas, in northern or southern climates, and in any season.

(EPA, https://www.epa.gov/heatislands/learn-about-heat-islands#heat-islands)

The heat assessment project (“Heat Watch”) involves collecting high-resolution near-surface air temperature (NSAT) data for the purpose of developing a predictive temperature and heat index model (Houston example), that takes into account the impact of land cover and topography on temperature. Deliverables provided by the project include maps of predictive surfaces, study data (temperatures) and a final report describing the methods, results, and initial interpretations.

As noted in the community examples below, the information generated by this project ties into many existing programs and priorities, including public health, energy efficiency, resilience, climate preparedness, emergency management, urban forestry management, land use planning, social equity, and community partnerships and engagement.

Below are examples of how heat mapping has supported other cities.

• Portland (OR) combined the heat mapping data with demographic information and air quality data to better characterize the risks of the urban heat island effect and poor air quality on vulnerable communities. The information is also being used to inform heat mitigation strategies such as cooling centers, drinking water distribution hubs, and tree plantings.

• Richmond (VA) is using the mapping project to inform the next long-range city planning document (Richmond 300) and the next round of sustainability planning (RVA Green 2050). One Richmond heat-mapper noted that since the project was done in July 2017, “public chatter about the urban heat island effect and its impacts on energy, health, and infrastructure has been markedly present throughout the year.” 

Data are collected in three 1-hour blocks over the course of one day; the optimal temperature threshold for collecting data is typically about the 90th percentile of annual daily highs. Data are collected by mounting a temperature sensor on the passenger side of a car and driving the vehicle across one of a number of sub-areas spanning Grand Junction. Those data are then used to create an area-wide predictive model based on the statistical relationships between land cover and temperature. Community scientist volunteers will serve as drivers and navigators. 

Satellites are good at estimating the temperature of surfaces from the birds-eye view; this means that satellite temperature datasets consist of temperatures measured at varying heights, including rooftops, the top of tree canopy, or the actual surface of a roadway or parking lot. With air temperature we can more closely understand what human beings are experiencing at 1 to 2 meters above the ground, more accurately reflecting what impacts our health and wellbeing during heat events.

No, we need all the routes to be driven by car so that data is collected in the same way across the City. Having different data collection methods makes it more challenging to clean and model the collected data. By driving a car, volunteers can maintain a consistent speed and navigate routes where safe bike infrastructure might not be present.

We will be recording data for each route three times on campaign day (6-7 am, 3-4pm, and 7-8pm). Volunteers will be needed for each of those 1-hour shifts. It is extremely helpful if a volunteer is able to attend multiple shifts on the day.