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Changing Hurricanes

Slide 1-13 for Lesson 4

Hurricane Resilience Unit

Feb 12, 2020

(BRENDAN SMIALOWSKI/AFP/Getty Images)

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1895 USA 2018

Feb 12, 2020

Have any of you seen this graphic before?

It’s a visualization of data.

Each stripe of color represents the average temperature during a year. (This is data for the US specifically.)

Years that were cooler are shown in blue colors. Darker blue is even cooler.

Years that were warmer are shown in red and pink colors. Darker red is the warmest.

The stripes on the left are older. The stripes on the right are more recent.

Notice that more cooler colors on the left and more warmer colors on the right.

It’s not a smooth transition; there were old warm years and recent cool years, that is climate variability, but on the whole the US has warmed.

Hurricanes now occur within a much warmer world than in our previous experience. And they are being affected.

Climate is predicted to continue warming in this century.

While estimates vary, sometime later this century, global climate will be 2°C warmer.

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Today’s question:�

“What if historical storms happened again�in a world that is warmer by 2°C?”

Feb 12, 2020

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Predicting the Future with Models

Feb 12, 2020

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Computer Simulations

Feb 12, 2020

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Simulating Hurricanes

Feb 12, 2020

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We are going to use computer model data� to explore the question� �“What if historical storms happened again�in a world that is warmer by 2°C?”

Feb 12, 2020

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A New Era of Hurricane Impacts

... so are we.

Hurricanes are changing ...

Feb 12, 2020

So, we can look at many of these simulations and count and track hurricanes. What are these simulations telling us?

They are telling us that we are in a new era of hurricanes impacts.

Hurricanes have changed. So have we.

(Image from NOAA’s GOES East satellite showing Hurricane Harvey making landfall on the Texas coast.)

How might you think hurricanes are changing?

(No matter which hurricane or tropical storm they analyzed, students will find that rainfall, winds, storm footprint, and flooding increase in a warmer world.)

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So, hurricanes have changed.

More intense, surge higher and rain totals higher.

Also, we are changing the way we are living along coasts:

Coastal populations have increased in many areas.

We’re going to review now what is known about how hurricanes will continue to change as climate warms and what scientists are still investigating.

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Heavier Rainfall

Thomas B. Shea/Getty Images.

Houston’s risk of extreme rainfall has quadrupled�

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Stronger Winds

Mexico Beach after Hurricane Michael

(Dronebase/Reuters) (HANDOUT/Reuters)

Feb 12, 2020

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Higher Storm Surge

Feb 12, 2020

kenshane/twitter.

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More or Fewer Hurricanes?

Feb 12, 2020

Become a Scientist!

But we are seeing more of the strongest storms

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What if Hurricane Isaac slowed down to half speed?

Feb 12, 2020

Rainfall totals double everywhere