A Hot Future

September 16, 2022

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A heat index greater than 125° F is expected to affect 8 million Americans this year, according to a study by the climate research group First Street Foundation. Heat index, also called an “apparent temperature” is a value adjusted to consider air temperaure and humidity.

The National Weather Service considers a heat index greater than 125° F in their “extreme danger” category. By 2053, this extremely dangerous heat could reach 13x more people: about 107 million Americans. 

Studies are also expecting future heat waves to increase in length. By 2053, temperatures in the current seven hottest days of the year are expected to linger for 18 days, according to the same study. In the Southern half of the nation, the hottest week of the year could become the hottest month, with 30 consecutive extreme heat days. 

These regions, where temperatures are likely to increase more than in others, create an “extreme heat belt”. This belt sprawls from Texas to the Great Lakes region. Another smaller belt stretches along coastal regions of South Carolina to Virginia. 

A Global Issue

Tropical regions are in for a much more dangerous ride. By 2050, people could experience dangerous heat (temperatures above 103° F) on most days of the year. Days of “extremely dangerous heat”, however, could double by then. These are days with temperatures at or exceeding 124-125° F! 

The problem is, many countries and businesses are aiming for net-zero emissions only by that year, 2050. 

Solutions

How can we adapt to such catastrophic change that is predicted to occur? Aside from cutting down on fossil fuel emissions, adaptation is now essential to avoid the worst effects of upcoming heat waves. The Center for Climate and Energy Solutions lists some strategies that can be taken by nations to build resilience to heat. 

• Installing cooling roofs. In the US, about 60% of urban spaces are covered with roofs traditionally made of dark materials with low solar reflectance (5-15%) that absorb about 90% of the sun’s light. This heat energy is transferred to the ground or buildings below. Cooling roofs can reflect more than 65% of the sun’s light while transferring only 35% of its energy. Cities such as New York, Philadelphia, Houston, and Chicago have implemented different levels of cool roof initiatives. Similar initiatives are working globally, in cities such as Buenos Aires and Cape Town.
  • Similar solutions include cooling pavements.
• Identifying vulnerable populations and creating plans to prepare communities for heat waves. Examples include creating community cooling centers, identifying heat thresholds (for example, communities without widespread air conditioning may have lower heat thresholds), and using media channels to warn residents. Cities such as Athens and Seville are working to categorize heat waves by threat level- similar to hurricane warnings. Such categorizations can give communities an indication of the danger of an upcoming heat wave. 
• Planting trees to provide shade and to cool the air through the process of evapotranspiration. For example, Pakistan has planted over 1.5 billion trees under their former Prime Minister Imran Khan and his administration. Despite this “10 Billion Tree Tsunami” being slammed by some environmentalists for poor planning and execution, the project (if completed) is estimated to absorb 500 million tonnes of CO2 by 2040. Putting this into perspective, the nation’s total emissions in 2018 were 489.87 MtCO2e. However, the possibility of this plan’s completion is now jeopardized by the nation’s new Prime Minister, Shehbaz Sharif, who has not historically cited climate action as a priority. 
• Building energy efficiency to reduce reliance and demand on electricity grids. During a heat wave, electricity grids are pushed to their breaking point by the physical effect of heat on the grid and by people using air conditioning for extensive periods of time. Building sustainable, green energy grids that can withstand heat waves is essential to keep communities powered up moving forward. 

Humans are resilient creatures- our existence is based on our ability to adapt. And despite these daunting times ahead, adaptation may bring a cool future to look forward to.