Climate Change: Where do we go from here?

We’ve all heard the old saying, “You know what they say about [city or state]; if you don’t like the weather, wait ten minutes, and it will change.” Some believe Mark Twain was the first to say this about New England, while others claim Will Rogers said it about Oklahoma. Either way, people around the nation make this same claim.

Although we know about rapidly changing weather, what about climate? Climate changes too, but gradually and over a longer period of time. Climate change affects more than our comfort and convenience. It creates conditions that affect people’s health—and scientists project that trend will continue and worsen throughout the 21st century.

At a recent CDC Grand Rounds, climate and health experts shared information about changing disease patterns, health issues related to climate change, and the findings of the Third National Climate Assessment.

How can we tell the climate is changing?

Scientists and weather experts measure and evaluate changes in s climate factors that can harm health. The Third National Climate Assessment provides evidence of these changes.

• Warmer temperatures
  Weather records show that the average U.S. temperature has increased by about 1.5°F (0.8°C) since 1895. Since the 1980s, records indicate that periods of frost have decreased. The upper Midwest has become much warmer, especially Minnesota. Extreme heat events formerly covered 0.1% of the earth; now they cover 10%.

• More precipitationHeavy downpours have increased in most U.S. regions as more rain is falling in less time, and there is more rain and less snow.

• More extreme weather events
  Heat waves, floods, and droughts are more frequent and intense. The number of Category 4 and 5 hurricanes in the North Atlantic has increased since the early 1980s.

• Higher sea level
  Due to temperature increases, sea level has risen about 8 inches since 1880. Also, carbon dioxide absorption has increased ocean acidity 26% since the industrial era began.

How do these changes affect people’s health?

When we think about how climate affects health, we often think about extreme temperatures and increased precipitation. But climate changes also affects other environmental factors that can cause health problems.

More pollen: Longer warm seasons mean longer pollen seasons. From 1995 to 2011, pollen seasons lasted two weeks longer in some northern cities.

Spreading wildfire smoke: Heat brings increased evaporation, which contributes to drought and leads to wildfires that can affect breathing 1000 miles away.

More algal blooms: Earlier springs, extreme heat, and more rain, have increased harmful algal blooms. In 2014, flooding rains came early to Toledo, OH, washing fertilizer into local lakes. The organic fertilizer fed the growth of blue-green algae that poisoned the local water supply, forcing Toledo residents to drink bottled water.

More viruses and bacteria: Longer warm seasons and extreme heat allow more bacteria and viruses to multiply more quickly.