NOAA Adopts New Normal: Hotter, Wetter

NOAA has updated its climate statistics for the U.S. Every 10 years, the agency comes up with a “new normal” based on the last 30 years of data. The most recent 30 years, compared to previous averages, shows that our climate is getting hotter and wetter (at least in the Houston area).

The “normals” help farmers, energy companies, water managers, transportation schedulers and others whose businesses depend on weather plan their activities. That includes your local TV weather casters who constantly compare what they predict for tomorrow with what has happened in the past.

What’s Normal – From 30 years Down to The Hour

The NOAA stats come in annual, seasonal, monthly, daily and even hourly tables. Because the normals have been produced since the 1930s, they also help put current weather in a historical context.

The New York Times produced a series of animated “heat” maps that show changes in temperature and precipitation for those 30-year windows from the 1930s to today. Heat maps in this sense do not refer to temperature but to colors that reflect temperature or precipition differences. Hotter colors like red and orange reflect increases. Cooler colors like green and blue reflect decreases.

Choose Your Start/Stop Points Carefully

Curiously, the animations show the U.S. getting both hotter and colder through the decades. Likewise with wetter and drier. You can clearly see alternating cycles of hot and cold, wet and dry. As cycles come and go, where you chose your start and stop points lets you support or disprove your favorite climate change hypothesis.

The change is especially drastic between the new normals and the previous ones, from 2010. “Almost every place in the U.S. has warmed,” Dr. Michael Palecki told the Times. He manages the project at NOAA’s National Centers for Environmental Information.

Palecki claims the world has warmed by more than 1 degree Celsius (about 1.8 degrees Fahrenheit) since 1900, and that the pace of warming has accelerated in recent decades.

However, if you compared 1921-50 with 1941-70, you might think the world was cooling. The same goes for large parts of the county with dry/wet cycles. Although the Houston region has experienced increasing wetness on a fairly consistent basis, you can see drought ebb and flow through other parts of the country.

If you use 1900 as your start point and today as your stopping point, Palecki says the world has warmed by more than 1 degree Celsius (about 1.8 degrees Fahrenheit) and that the pace of warming has accelerated in recent decades.  The precipitation maps show the Southwest becoming increasingly drier, while the Central and Eastern parts of the country are getting wetter.

Says NOAA, “Most of the U.S. was warmer, and the eastern two-thirds of the contiguous U.S. was wetter, from 1991–2020 than the previous normal period, 1981–2010. The Southwest was considerably drier on an annual basis, while the central northern U.S. has cooled somewhat.”

For More Information

Check out the fascinating NY Times article or go straight to NOAA for far more detailed information.

Like all NOAA statistics, they are publicly available. You can even customize your own data searches based on time and location.

Posted by Bob Rehak on 5/13/2021 based on information from The NY Times and NOAA

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