The length of annual heat streaks — the number of consecutive hot days — is increasing in these cities.
Climate change is one reason the area burned by western wildfires is increasing.
The number of large wildfires in the West is rising and climate change is playing a role.
Trends in nighttime temperatures are a symptom of a world warming from from climate change.
See the trend in hot days in these U.S. cities.
A small increase in average temperature leads to a big increase in extreme heat.
The first day with summer-like temperatures is happening earlier for most of these cities.
The amount of carbon dioxide in the atmosphere has a strong correlation with rising temperatures.