Category: Weather

Earth's Emergency Heat Valve: The Hurricane

6/2/2022

Vicki Cobb
The Master Chef of Kids' Hands-on Science

Earth has a problem. The sun creates hot spots over land, in the air and in the water. That’s why there are winds, weather, and currents in the ocean as Earth tries to even out the heat, moving warmer masses of air and water to cooler areas.

During hurricane season ( from June 1-November 30), only 10 or 11 of the 80 tropical disturbances off the west coast of Africa (where most of our hurricanes originate) become large enough storms to be given a name. Only two or three of them hit the United States. They are not frequent but they are massive wind storms that can destroy life and property.

Do they do anything good at all? As far as the Earth is concerned, these largest of all storms are a safety valve to rapidly move heat that has been accumulating in the oceans up to the stratosphere (from 7 to 31 miles above the Earth’s surface). From there it will be transported through the air to over the North Pole. It’s the way Earth stops a fever.

Once a hurricane forms, it must have an ocean surface that is at least 80°F to keep moving and to grow. Under the storm, huge amounts of warm water become water vapor. Warm moist air rapidly rises through the spinning winds of the hurricane, up to the stratosphere. When moist air reaches the frigid (-70°F) stratosphere the water vapor quickly condenses to liquid water (rain) releasing its heat. This heat makes surrounding air molecules move faster forming winds.

How do hurricanes cool off the oceans? How do they move the heat? Here’s a clue: Wet your finger and wave it in the air. How does it feel? Pretty cool, I bet! That’s because the heat from your finger changes liquid water into water vapor (a gas) as your finger dries. Water vapor molecules store this extra heat. They rise because they are lighter than other air molecules.

So, a hurricane is a heat engine that moves water vapor from the ocean’s surface high enough to condense back into liquid water and release heat safely to the stratosphere forming rivers of wind that move it to the poles.

Scientists predict that global warming will increase the number and the power of the hurricanes as the ocean surfaces become increasingly warmer during our summers.

This diagram of the anatomy of a hurricane shows the direction of the winds. The blue represents cold air descending while the pink shows warm moist air rising. The outflow surface clouds form as water condenses into a "table-top" cloud, releasing heat that becomes wind. Kelvinsong via Wikimedia

Hurricane Isabel (2003) as seen from orbit during Expedition 7 of the International Space Station. The eye, eyewall, and surrounding rainbands, all characteristics of hurricanes, are clearly visible in this view from space. Image courtesy of Mike Trenchard, Earth Sciences & Image Analysis Laboratory, NASA Johnson Space Center

Vicki Cobb's How Could We Harness a Hurricane? offers questions and provides new points of view that may just change peoples' thinking by showing young readers the work scientists and engineers are doing to avoid future disasters. The book includes hands-on experiments that make science fun, be it at home or in the classroom. Here's a link to the book' s Trailer.

How Could We Harness a Hurricane was named a 2018 Best STEM Book K-12 by the National Science Teachers Association and the Children's Book Council.

Vicki is a member of iNK's Authors on Call so you can invite her to your classroom via iNK's videoconferening Zoom Room. Click here to find out more:

MLA 8 Citation
Cobb, Vicki. "Earth's Emergency Heat Valve: The Hurricane." Nonfiction Minute,
iNK Think Tank, 24 Apr. 2018, www.nonfictionminute.org/
the-nonfiction-minute/Earths-Emergency-Heat-Valve-The-Hurricane.

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Climate Change: The Facts and the Consequences

4/28/2022

11 Comments

Dorothy Hinshaw Patent
Nature’s Animal Ambassador

The polar jet stream can travel at speeds greater than 100 miles per hour (160 km/h). Here, the fastest winds are colored red; slower winds are blue. NASA/Goddard Space Flight Center

No one can honestly deny that our climate has been changing in recent years. Before the winter of 2018-2019, California had only a year’s water supply stored in its reservoirs. Wildfires have become an annual threat throughout much of the west, while the Midwest and East Coast have experienced record-setting winters. These problems are due to complex interactions among temperature, winds, and water currents.

A major change is the warming of the atmosphere. The earth’s atmosphere has been getting warmer since the late 1800s, when factories started spewing out carbon dioxide. Because natural variations also affect the temperature, a graph showing the temperature over time is a jagged line. But the trend is consistently upward and follows the graph of increasing carbon dioxide in the atmosphere due to human activities. That’s strong enough evidence that we are at least a large part of the problem, and the vast majority of climate scientists are urging countries of the world to reduce their carbon dioxide emissions.

A major player in the world’s weather is the jet stream, which helps circulate the atmosphere around the world about every two weeks. This flow of fast-moving air speeds across North America from west to east, separating cold arctic air from warmer, more southerly air. The jet stream used to run in a fairly direct arc across the northern United States. But in recent years it has become less stable, dipping southward in the eastern U.S. to bring frigid winters to the Northeast while arching northward in the West, carrying warm, dry air there. Scientists believe that the rapid melting of the Arctic ice brought about by global warming is part of the cause for the jet stream’s instability.  However, climate trends are controlled more by the oceans. Scientists estimate 95% of the heat from global warming is being stored in the oceans, increasing water temperatures even into the depths.

As global warming continues, so will climate change. The melting of sea ice and glaciers is already raising the sea level. While scientists don’t blame climate change for devastating Hurricane Sandy, Sandy’s extreme coastal flooding was made worse by the increase in sea level that’s already occurred. As time goes on, coastal cities around the world will be at increasing risk for more severe storm damage.

Because warm air holds more moisture than cold air, storms are becoming more severe, increasing blizzards and flooding storms. Some agricultural regions that depend on reliable rainfall may soon be unable to grow crops, disrupting the food supply.

Climate change is complicated, but because it affects us all, we need to learn about it.  The Environment Protection Agency has questions and answers about climate change.

Oceans cover 71% of the Earth’s surface and contain 97% of the water on our planet. This chart shows how this water has absorbed the vast majority of the increased atmospheric heat due to global warming.

This chart shows how carbon dioxide in the atmosphere has increased since 1960. The measurements are made near the top of Mauna Loa on the island of Hawaii, thousands of miles away from any land-based major pollution.

Calculations of global warming prepared in or before 2001 from a range of climate models. The projections assume no action is taken to reduce emissions.

Yellowstone National Park’s majestic geologic wonders and remarkable wildlife draw millions of visitors each year. But there was a time when these natural treasures were in great danger, all because after years of unrestricted hunting, one key piece of the puzzle had been eliminated—the wolf.

Now, more than a decade after scientists realized the wolves’ essential role and returned them to Yellowstone, the park’s natural balance is gradually being restored. Dorothy Hinshaw Patent's text supplemented by spectacular full-color photographs show the wolves in the natural habitat that was almost lost without them. Click here to find out more.

Dorothy Hinshaw Patent is a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more.

MLA 8 Citation
Patent, Dorothy Hinshaw. "Climate Change: The Facts and the Consequences."
     Nonfiction Minute, iNK Think Tank, 17 Apr. 2018,
     www.nonfictionminute.org/the-nonfiction-minute/
     Climate-Change-The-Facts-and-the-Consequences.

11 Comments

Defining Weather, Global Warming, and Climate Change

4/27/2022

2 Comments

Dorothy Hinshaw Patent
Nature’s Animal Ambassador

People are confused. They hear the terms “global warming” and “climate change” tossed about without much explanation. We all talk about the weather, but what does that word actually mean, and how does it relate to these other terms?

NASA defines global warming: “Global warming is the increase in Earth’s average surface temperature due to rising levels of greenhouse gases.” So global warming is a measurable statistic. Record the temperature at many sites on Earth for a given year, add them up, and divide to get an average. Rising levels of greenhouse gases are also well measured. The famous “Keeling curve” of atmospheric CO2 begun in Hawaii in 1957 is the best example.

Climate change is more complicated. Climate change is a long-term change in the Earth’s climate and includes measures of the atmosphere, oceans, land, cryosphere (snow and ice), wind, precipitation, deforestation, wildfire, and more, as well as temperature. So, climate change is a more inclusive measure of many factors changing the Earth system, which is very different from a single statistic like the rise in temperature from global warming.

Then there’s the weather. What, exactly is the weather? That term refers to what’s going on in the atmosphere at a particular time and place. It includes the air temperature, wind speed, humidity, and precipitation. Weather happens day to day, while global warming is shown by recording day-to-day temperatures over a long period of time. Climate change is a long-term process that can result in drastic changes in conditions on our planet.

To sum up: Weather refers to what’s happening in the atmosphere at a given time and place over the course of days to months.

Global warming refers to an upward trend in the average temperature over a period of years to decades.

Climate change is a long-term process that can be influenced by changes in the average temperature but includes many other factors.

To watch a brief but amazing video of the affect of global warming and climate change over the next 20 years, click here.

Dorothy's recent book The Call of the Osprey, has been chosen as a Best Science Trade Book for Students by the National Science Teachers Association. It covers research being done in Western Montana by scientists at the University of Montana. Starting in the late 1800's, Butte, MT, at the headwaters of the Clark Fork River, was the largest copper mine in the U.S. The major result of the mining was two-fold—the electrification of America and the largest Superfund cleanup site in the U.S. Call of the Osprey deals not only with current research but also with the history of Butte and the lives of the scientists involved in the research. Click here to find out more.

Dorothy Hinshaw Patent is a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more.

MLA 8 Citation
Patent, Dorothy Hinshaw. "Defining Weather, Global Warming, and Climate Change."
     Nonfiction Minute, iNK Think Tank, 16 Apr. 2018,
     www.nonfictionminute.org/the-nonfiction-minute/
     Defining-Weather-Global-Warming-and-Climate-Change.

2 Comments

The Magician of Iron

4/12/2022

6 Comments

Roxie Munro
Visual Thinker

The great Paris tower was underway. From each corner of a broad base the size of a football field, four spidery iron structures rose, curving inward in one majestic sweep toward the middle. The construction – a web of connecting girders – called for 300 workers to assemble some 15,000 pieces of iron and snap 2.5 million rivets into place. This would be the world’s tallest man-made structure, reaching a height of 300 meters (934 feet). A glorious demonstration of engineering, it was conceived by Gustave Eiffel, the most illustrious engineer of nineteenth-century France.

The tower was to be the focal point of the International Exhibition of Paris in 1889, commemorating the 100th birthday of the French Revolution. After that, since it had no practical use, it was to be torn down.

It took two years, two months, and three days to build the Eiffel Tower. Eiffel used wrought iron, which was a relatively new building material at the time, used primarily for bridges and aqueducts. As the tower rose, becoming the city’s most prominent feature, not everyone approved. “Useless and monstrous,” one newspaper called it. Another described it as an “odious column of bolted metal.”

Called the Magician of Iron, Eiffel’s mathematical prowess and attention to detail was legendary. To put the tower project on paper took 30 draftsmen working full time for 18 months. Every rivet of the 2.5 million needed for the structure had its designated place, down to a fraction of a millimeter.

The Tower became the hit of the International Exhibition, with nearly two million people visiting it. Still, not everyone loved this prodigious web of steel girders. A famous writer was once asked why he ate lunch there every day, since he was known to hate the sight of it. He replied, “Because it’s the only place in Paris where I can’t see the damn thing.”

So why wasn’t the Eiffel Tower torn down? It almost was. What saved it was the radio broadcasting center and the weather station that Eiffel installed at the top.

Now France’s most famous landmark, it is not the only national symbol that Eiffel was involved with. He also built the iron skeleton of a lady we’re all familiar with: The Statue of Liberty.

As for the Eiffel Tower, “I ought to be jealous of that tower,” he once said. “She is more famous than I am.”

The Eiffel Tower under construction highlights the intricacy of the design as well as the massive size of the project in relation to the city of Paris. Art by Roxie Munro

After dark during the 1889 Exposition, the newly-opened tower was lit by hundreds of gas lamps, and a beacon sent out three beams of red, white and blue light. Georges Garen via Wikimedia Commons

The Parisian art community criticized the tower even before it was built, calling it "a giddy, ridiculous tower dominating Paris like a gigantic black smokestack, Eiffel responded, "The tower will be the tallest building that men have ever built. ...And why would that which is admirable in Egypt become hideous and ridiculous in Paris? ". Wikimedia Commons

Eiffel's most famous works are still major tourist attractions in the 21st century. The Eiffel Tower is the most-visited paid monument in the world. An average of 25,000 people ascend the tower every day. Approximately four million people visit New York's Statue of Liberty National Monument and Ellis Island each year. Photo Benh Lieu Song viia Wikimedia Commons. Art by Roxie Munro

One of Roxie's most recent, Masterpiece Mix, is a book about art. As an artist searches for inspiration, she explores thirty-seven paintings of different genres, and comes up with a grand finale, using all of them. The book has "smart, concise, marvelously amplifying backmatter" (Kirkus), a dedicated web page, and free downloads.

MLA 8 Citation
Munro, Roxie. "The Magician of Iron." Nonfiction Minute, iNK Think Tank, 7 Mar.
2018, www.nonfictionminute.org/the-nonfiction-minute/The-Magician-of-Iron.

6 Comments

Flying into the Eye of a Storm

10/5/2021

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Vicki Cobb

The Master Chef of Kids’ Hands-On Science

Dr. Hugh Willoughby, of Florida International University, was one of the first meteorologists to ever fly into the eye of a hurricane.  Now the job is done by the Hurricane Hunters—a team of pilots, navigators and meteorologists who fly into these dangerous storms to help keep us safe.  Here’s what I learned when I interviewed Hugh Willoughby:

What is a hurricane eye?

Hurricanes are circular storms so the wind blows around in a circle. The eye is the center of a hurricane.  If a circular storm doesn’t have an eye, it is not a hurricane—it’s a tropical storm.  The eye is surrounded by a ring of clouds called the eyewall. Within the eye, there is a calm area that is cloudless all the way up to space.   The winds are strongest just at the inner edge of the eyewall, which is composed of violent thunderstorms with strong updrafts and downdrafts.   The hurricane pinwheels out from the eyewall as spiral bands of wind and rain, which stretch for miles.  When a hurricane’s eye passes over land, the storm suddenly stops and the sun comes out.  But the relief is short-lived as the other side of the storm soon slams into the area.

How do Hurricane Hunters help us?

Hurricane Hunters fly into the eye of hurricanes that are heading towards our shores to help predict where the storm will make landfall.  On every mission they must find the center of the storm at least twice and at most four times over a period of several hours because the change in position of the center of the eye tells us the direction the storm is moving and how fast it is moving. They also drop packages called dropsondes that contain measuring instruments for air pressure, humidity, and wind speed at the eyewall.  These measurements tell us the destructive power of the storm or its “category.” During a hurricane season (from June 1 to November 30) the Hurricane Hunters and their fleet of ten airplanes can get data on three storms, twice a day.  So flying into a hurricane’s eye is pretty routine for them.

Is it dangerous?

The planes can easily handle changes in air pressure and wind speeds that create “bumps” and it can be pretty bumpy going through the eyewall.   But, in more than sixty years there have been only four accidents. All on board agree that the view of the eyewall from inside the eye is worth it! The plane has transported them inside nature’s most magnificent amphitheater.
(c) Vicki Cobb 2014

Harvey and Irma have alerted everyone to the dangers of a hurricane. We can predict the course of a hurricane by flying into a hurricane and repeatedly measuring wind speed, humidity, air pressure, and temperature. Here's a video that will give you a taste of what it looks like as you approach an eye wall. It is filmed from a plane penetrating Hurricane Katrina.

When you hear about a Category "3" hurricane, or any other category number, the Saffir-Simpson Scale tells you just what that number means.

Look at the amazing number of instruments contained in a Dropsonde.

Vicki Cobb's latest book, How Could We Harness a Hurricane? shows how the scientific understanding of air, water and energy come together to form hurricanes. It includes lots of hands-on activities that you can do. Engineers look at science and try and figure out ways the steer a hurricane away from populated areas or weaken them. There are lots of questions in the book and some of them don't have answers, yet.

MLA 8 Citation
Cobb, Vicki. "Flying into the Eye of a Storm." Nonfiction Minute, iNK Think Tank, 18 Sept. 2017, www.nonfictionminute.org/the-nonfiction-minute/ flying-into-the-eye-of-a-storm.

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Earth's Emergency Heat Valve: The Hurricane

Climate Change: The Facts and the Consequences

Defining Weather, Global Warming, and Climate Change

The Magician of Iron

Flying into the Eye of a Storm

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