Using Google Earth to Assess Shade for Sun Protection in Urban Recreation Spaces: Methods and Results

Area of Science:

• Environmental Health
• Urban Planning
• Public Health

Background:

• Public spaces offer shade, reducing risks of sunburn and skin cancer.
• Current shade auditing methods are site-specific and weather-dependent.
• Innovative, accessible tools are needed for urban shade assessment.

Purpose of the Study:

• To evaluate Google Earth's feasibility for assessing shade in urban open spaces.
• To develop and test a shade projection method using Google Earth.
• To assess the accuracy and reliability of this novel shade auditing technique.

Main Methods:

• A shade projection method using Google Earth street view and aerial imagery was developed.
• Shade cover was estimated at solar noon on the summer solstice.
• Three researchers assessed shade in 45 New Zealand urban open spaces, including playgrounds, beaches, and pools.

Main Results:

• 83% of identified activity areas lacked shade cover.
• The method accurately assessed shade in playgrounds (85% identified) and beaches (93% identified).
• Excellent inter-rater reliability (ICC=0.97) was achieved; outdoor pool assessment was limited by image availability.

Conclusions:

• Google Earth provides a reasonably accurate and reliable tool for shade audits in playgrounds and beaches.
• This method supports urban planning for healthy public spaces.
• Further development may enhance its utility for diverse urban settings.