Scientific studies indicate that many of the extreme weather events you see in these pictures are likely to become more frequent or more intense with human-induced climate change.
Long-term changes in climate can directly or indirectly affect many aspects of society in potentially disruptive ways. For instance, warmer average temperatures could increase air conditioning costs and affect the spread of diseases, and while increased precipitation can replenish water supplies and support agriculture, intense storms can damage property, cause loss of life and population displacement, and temporarily disrupt essential services such as transportation, telecommunications, and energy.
In the US, average temperatures have risen across the contiguous 48 states since 1901, with an increased rate of warming over the past 30 years.
Nine of the top ten warmest years on record have occurred since 1998. Average global temperatures show a similar trend, and all of the top 10 warmest years on record worldwide have occurred since 2005. Within the United States, temperatures in parts of the North, the West, and Alaska have increased the most.
As the Earth warms overall, average temperatures increase throughout the year, but the increases may be larger in certain seasons than in others.
Since 1896, average winter temperatures across the contiguous 48 states have increased by nearly 3°F. Spring temperatures have increased by about 2°F, while summer and fall temperatures have increased by about 1.5°F.
Many extreme temperature conditions are becoming more frequent. Since the 1970s, unusually hot summer days (highs) in the US have become more common over the last few decades. Unusually hot summer nights (lows) have become more common at an even faster rate.
This trend indicates less "cooling off" at night and although the country has experienced many winters with unusually low temperatures, unusually cold winter temperatures have become less common—particularly very cold nights (lows).
Heat waves are occurring three times more often than they did in the 1960s—about 6 per year compared with 2 per year.
The average heat wave season is 49 days longer, and individual heat waves are lasting longer and becoming more intense.
A new report by top climate scientists and meteorologists describes how climate change drove unprecedented heat waves, floods, and droughts in recent years — the annual report from the American Meteorological Society (AMS) compiles the leading science about the role of climate change in extreme weather.
"It's a reminder that the risk of extreme events is growing, and they're affecting every corner of the world," Sarah Kapnick, the chief scientist at the National Oceanographic and Atmospheric Administration (NOAA), told NPR.
