Heat waves are one of the leading weather-related causes of death in the Unites States. Recognizing the current and future extreme heat risk to its population, New York City decided to assess climate risk and vulnerability. To assess the risk of future extreme heat events, the New York City Panel on Climate Change used the most up-to-date global climate models at the time. The Panel's Climate Risk Information Report identified a baseline, covering the period 1970-2000, of two heat waves per year on average. New York City projected the number of heat waves could increase, using the 90th percentile as the high estimate, to seven per year by 2050. Additionally, the Panel's 2013 report states the average annual number of days over 90°F could more than triple, under the high estimate, from 18 to 57 by 2050.
New York City updated its emergency response and hazard mitigation plans as a result of its Climate Risk Information Report. New York City is continuing to refine their climate projections to better assess climate vulnerability under the best-available science. The most recent update was in the 2015 New York City Panel on Climate Change: Building the Knowledge Base for Climate Resiliency Report, which for the first time included projections to the year 2100.
To assess climate risk, New York City derived temperature and precipitation projections by using a matrix of 35 Global Climate Model simulations under two Representative Concentration Pathways. (Learn more about how to make these models on the U.S. Global Change Research Program Models website.)
New York City then incorporated climate risk data within its adaptation and response plans. The City established a city panel -- the New York City Panel on Climate Change -- to inform its climate activities. After developing a Climate Adaptation Plan and updating it in 2015, New York City incorporated climate risk and vulnerability to heat events within the Hazard Mitigation Plan.*
New York City also educates residents on the threats from extreme heat and provides preparedness resources. New York City created multiple resources including handouts, guides and even an emergency preparedness mobile app to help residents prepare for extreme heat events.
To re-assess vulnerability under the best available science, the City updated its vulnerability assessment in the 2015 report “Building the Knowledge Base for Climate Resiliency.” The report, for the first time, projects climate risk out to 2100
*Note: New York State Requirement §F6 requires plans developed with State Office of Emergency Management administered funds to include climate change hazard information and strategies to address them.