National Aeronautics and Space Administration

National Climate Assessment

NASA National Climate Assessment (NCA) Activities

NASA Indicators Solicitation Proposals

Development and Testing of Potential Indicators for the National Climate Assessment

Lead PI and Center: Stephanie Weber, Battelle Memorial Institute
Title: Using NASA Earth Science Datasets for National Climate Assessment Indicators: Urban Impacts of Heat Waves Associated with Climate Change

This project will draw on NASA Earth science datasets and other physical and socioeconomic data to help urban governments assess: How vulnerable is our city's population to increasing heat waves associated with climate change?

Heat waves have been increasing globally in the past 5-10 years and are projected to continue increasing throughout the 21st century.  The vulnerability of a city's population to heat waves reflects exposure to extreme heat events, sensitivity of the population to impacts, such as adverse health effects, and adaptive capacity to prepare for and respond to heat waves.  Vulnerability can be assessed at the city level and also comparatively among different parts of a city.  For example, some sub-populations are less resilient to heat waves than others, such as the elderly, the very young and the economically disadvantaged.  In addition, vulnerability to heat waves is exacerbated by the non-climate stressor of urban heat islands (UHIs).  As noted at the NCA Indicators Workshops, socially and economically vulnerable populations are especially at risk to the impacts of heat waves, due to increasing energy costs, air pollution, and heat-related illness and mortality.

The project team will engage urban stakeholders in a process to develop a set of vulnerability indicators that are focused on heat waves in urban areas.  The objective of this proposed work is to elucidate for urban governments the degree to which heat waves are changing, the real-life impacts of heat waves on urban populations, and the effectiveness of adaptation actions to reduce urban temperatures.  The proposed approach integrates physical, ecological, and socioeconomic information into a set of five related indicators that address vulnerability.  Based on stakeholder engagement in a 1st pilot city, the indicator methodology will be finalized and then implemented for the 1st pilot city and a 2nd pilot city as a test of scale-up.

The project team will utilize the following datasets in the development of the heat wave indicators:
- Land surface temperature from Aqua/MODIS,
- Land cover from Terra and Aqua/MODIS, to delineate urban areas,
- NDVI from Aqua/MODIS, to assess greenness as a cooling mechanism,
- Socioeconomic datasets from NASA SEDAC, such as U.S. Census grids, to identify disadvantaged/vulnerable groups,
- National Weather Service (NWS) Heat Advisories/Warnings, to help define city context-specific heat waves,
- U.S. EPA's UHI Community Actions Database, to identify and test adaptation programs to boost resilience, and
- Urban ozone levels from U.S. EPA's Air Quality System.

The proposed set of 5 indicators includes:
Exposure indicators:
- Urban Heat Wave Indicator: Heat index degree days in a single summer for "heat waves" defined by NWS Heat Advisories and Watches/Warnings
- Urban Heat Island Indicator: Difference between average urban and rural LSTs during heat waves
- Air Quality Indicator: Daily 8-hr maximum metropolitan O3 values during heat waves
Sensitivity indicator:
- Urban Socioeconomic and Hotspot Indicator: Classification of sensitivity of census block groups based on socioeconomic census and urban greenness data
Adaptive capacity indicator:
- Urban Adaptation Effectiveness Indicator: Measured reductions in LST or increases in NDVI in neighborhoods related to UHI reduction measures

The scale for each indicator will be categories of equal intervals, which will reflect both absolute values and trends with reference to a baseline period.  The proposed work demonstrates the value of NASA Earth science data for societal benefit in a scientifically rigorous manner; combines the social, ecological and physical aspects of climate change impacts and vulnerability; focuses on impacts that matter to people; highlights positive actions that can boost resiliency; and is grounded in stakeholder participation at the appropriate (urban) level.