Climate Change Fuels Unprecedented Heat Waves Across Northern Hemisphere
Climate change is intensifying dangerous heat waves across the Northern Hemisphere this week and is projected to continue causing extreme weather for decades, according to recent research.
“It is a worldwide heat wave that we are now suffering. That puts the heat under our decisions,” stated Christiana Figueres, former U.N. climate agency chief.
How Climate Change Drives Heat
The ongoing burning of fossil fuels releases carbon emissions into the atmosphere, trapping more heat from the sun and causing a rise in global average temperatures. Since the Industrial Revolution, the global average temperature has increased by nearly 1.3 degrees Celsius (2.3 degrees Fahrenheit). This higher baseline amplifies the intensity of heat waves, making them more frequent and dangerous.
“Any significant heat wave has been made substantially more likely and warmer than it otherwise would have been as a result of human-caused climate change,” UCLA climate scientist Daniel Swain said. There is extensive evidence supporting this conclusion.
Factors Influencing Heat Waves
While climate change is a major factor, other conditions also affect heat waves. Climate systems like El Niño and La Niña, regional circulation patterns, and land cover can all impact temperatures. Dark surfaces and built environments tend to get hotter than reflective surfaces or natural landscapes like forests and wetlands.
To determine the exact influence of climate change on a specific heat wave, scientists conduct “attribution studies” using computer simulations. For instance, World Weather Attribution scientists found that the April heat wave in South Asia was 45 times more likely due to climate change, with temperatures in Kolkata reaching 46°C (115°F).
Future Projections
Even if carbon emissions were halted today, existing emissions ensure that climate change will continue to drive temperatures higher for decades. According to the Intergovernmental Panel on Climate Change, global emissions need to be halved from 1995 levels by 2030 and reach net-zero by 2050 to keep the temperature rise around 1.5°C (2.7°F) above preindustrial levels. However, emissions have continued to rise, putting the world on track to hit 2.7°C (4.9°F) by 2100, surpassing the critical 1.5°C threshold.