Every year, extreme summer heat kills 100-plus New York City residents on average. They die from heat stroke and the heat-related worsening of chronic health problems. Hundreds more need hospital care for serious heat related illness, says the City.

Residents in upper Manhattan, large parts of the Bronx, and central-east Brooklyn are particularly at risk from extreme heat, the City has found. It is targeting vulnerable areas with heat mitigation strategies, like planting more trees, and adaptation measures, such as subsidizing the cost of air conditioning for low-income seniors and other residents with health issues.

Planning for extreme heat at the neighborhood level makes sense to researchers. The journal Environmental Health Perspectives mentions a summer 2006 heat wave in New York City which caused an 8 percent increase in nonaccidental deaths, including 40 heat-stroke deaths. The same article highlights a study finding that the risk of death from heat waves partially depends on local community characteristics, not just extreme temperatures.

“It is important for officials to develop local response plans on the basis of heat-wave mortality trends in their own communities; when it comes to planning for health effects of heat waves, one size does not fit all,” the journal notes.

Our Warming City

Heat -not rising sea levels- may be the greatest natural threat posed by climate change to New York City residents. Since 1900, temperatures measured in Central Park have risen 3.4°F, mirroring an increase that’s been seen throughout the entire Northeast.

heat wave bus stop
Waiting for a bus in New York City during a 2010 heat wave. Photo credit: the Daily Mail.

According to a report released by the New York City Panel on Climate Change this February, we can expect to see more days above 90°F, more days above 100°F, and more heat waves (three or more consecutive days above 90°F), too.

The NPCC report says that by 2080, the number of heat waves could triple—up to six per year. Average annual temperatures could increase 4.1 to 5.7°F by the 2050’s, and as much as 8.8°F by 2080.

Focusing on NYC’s Most Vulnerable Neighborhoods

The deBlasio administration has identified city neighborhoods most vulnerable to the impacts of extreme heat. This includes Central Harlem in Manhattan, large sections of South and Central Bronx, and areas of Brooklyn directly east of Prospect Park.

“The risk of death from extreme heat is highest among those without air conditioning, in neighborhoods with higher poverty rates, and where there is less land covered by trees and other vegetation,” states the administration’s just-released OneNYC sustainability and resiliency plan.

“Heat Vulnerability” by community district in New York City. Credit: nyc.gov

Cooling Neighborhoods & Homes Down

By greening neighborhoods and increasing access to air conditioning, the City aims to “reduce heat related illnesses and deaths, and reduce disparities in vulnerability to climate change.”

The City says it will evaluate the “best available science” on the urban heat island effect, invest in better data collection, and “develop effective capital investment and operational strategies to adapt our city to the increasing impacts of urban heat.”

More specific actions planned by the City include:

  1. Create an Urban Heat Island Working Group, which is already meeting, to identify heat mitigation and adaptation strategies benefiting New York’s most heat-vulnerable communities.
  2. Create a citywide air temperature monitoring system to collect community-level temperature data to guide heat mitigation and emergency response activities.
  3.  Update New York City’s 2010 LiDAR dataset through aerial data collection and other means. Updated data will help the City measure the extent of the tree canopy across the five boroughs, evaluate heat mitigation activities more accurately, quantify existing investments, and inform future strategies about how to plan the built environment.
  4. Call on the State to expand allocation of Federal Home Energy Assistance Program funds to assist low-income, heat-vulnerable populations (such as seniors and others with pre-existing health conditions) with air conditioning purchase and installation, and utility costs.
  5. Establish maximum allowable temperatures in residential facilities and supportive housing for vulnerable people by amending the city’s health code.