Global warming is causing more extreme hot and cold weather. Researchers analyzed how rising temperatures affect the likelihood of heatwaves and cold snaps. They found that as the earth warms up, extreme high temperatures become more likely due to increased average temperatures and temperature variations. Additionally, the warming of the stratosphere can make cold snaps more intense by strengthening the polar vortex. This means that extreme hot and cold weather events are influenced by global warming and may happen more frequently in the future.