Today’s is the final episode of Weather Break.  All this week, we’ve been talking about how weather features end, but that brings up a really interesting question– why doesn’t weather itself ever end?  After all, the atmosphere is under the influence of friction, which always acts to slow motions down, so why doesn’t the atmosphere eventually just come to a rest, with no more winds or storms or anything like that?  That’s actually a fascinating question to leads to an explanation of how the atmosphere fundamentally works as a heat engine, pumping excess heat from the tropical towards the very cold poles.  As long as the sun is shining and keeping the tropics warmer than the rest of the world, the atmosphere will keep working to spread that heat out more evenly around the planet, as we discuss on today’s final episode of Weather Break.

On behalf of everyone here in the Creighton University Department of Atmospheric Sciences, I’d like to thank everyone who helped make Weather Break a success for nearly four years and over 800 episodes.  Over the years, we’ve gotten assistance from many students — both in and out of the Department of Atmospheric Sciences.  We’ve had support from our friends at DoIT (Creighton’s Division of Instructional Technology) and from the many people who were gracious enough to be guests on the program.  We are grateful for the financial support of the NASA Nebraska Space Grant, which helped make the program possible.  Most of all, we couldn’t have done this program without the generosity of our friends at KINI and KBRB, who made air time available to us so that we could share our enthusiasm for everything about the atmosphere.  Thank you to all of you, and we’re already thinking about ways that we can continue bringing news and information about weather, climate and the environment to you in the future!

All storm systems eventually come to an end, and tornadoes are no exception.  There are actually quite a few different ways in which a tornado can stop causing damage (like, for example, simply lifting the funnel cloud off the ground).  However, one of the more dramatic and photogenic ways that a tornado can end is by going through its “rope stage”.  As the name implies, a tornado gets very long and narrow during this final stage of development before finally breaking up completely.  On today’s episode of Weather Break, we talk about the rope stage of tornadoes, and don’t forget to visit our website to see galleries of pictures of tornadoes in their rope stage.

Links

Here is a collection of videos about the rope stage of tornadoes.

Here is a gallery of images from the Spencer, SD tornado, including (towards the bottom of the page) examples of the storm in its rope stage.

There are lots of truly amazing pictures of rope stage tornadoes on the internet.  Perhaps the best that we can do is show you this Google Image Search on the term “rope stage tornado”.  Some of these images are incredible.

Some features in the atmosphere are more or less permanent– the subtropical high pressure systems, the trade winds, and the Intertropical Convergence Zone (ITCZ) are good examples.  However, most weather systems go through a clear life cycle, first forming, and later dissipating.  Thunderstorms are a clear example of this latter group.  On today’s episode of Weather Break, we talk about the processes at work in a thunderstorm that eventually cause the storm to fall apart.  We also discuss the strangely-named remnants of a thunderstorm– the “orphan anvil”.

Links

For more information about orphan anvils, visit:

• The National Weather Service
• Weatherscapes
• Climate Abyss

Like all weather features, cyclones go through a life cycle– first forming, then going through a “mature” stage, and eventually dissipating.  The processes that cause a cyclone to weaken and die are collectively known as “cyclolysis”.  As Weather Break marches towards its final episode this coming Friday, we decided to spend this week on the ways in which weather features end, with the spotlight being on cyclones today.  How does a broad area of low pressure suddenly have pressures that increase and return to normal?  Tune in to today’s episode of Weather Break for the answers!

Links

For more information about the life cycle of cyclones, visit:

• The University of Illinois
• The University of Wisconsin — Stevens Point
• Wikipedia

This is the final week of production of new episodes of Weather Break, and as the program winds down it got us thinking about the different weather features wind down or end.  A good example of this sort of process would be “frontolysis”, or how fronts eventually dissipate.  On today’s episode of Weather Break, we kick off the last week of the program by looking into the lives of fronts and how fronts eventually cease to exist.

Links

There are, of course, lots of great online resources about fronts and frontolysis.  Here are some examples that we particularly like:

• The University of Illinois:  Cold Fronts, warm fronts
• Wikipedia:  Frontolysis
• Integrated Publishing:  Frontolysis

When Dr. Jon Schrage of the Creighton University Department of Atmospheric Sciences was a kid, his grade school would always have boxes of scratch paper that were donated by the local National Weather Service office. The front side of the papers were covered with strange codes that none of the students could read, but the back of the paper was fine for use in doodling or drawing or whatever. The pages were printouts of communications between various meteorologists–something like printing email today. What was going on that meteorologists in the 1970s were communicating in code rather than just typing messages directly? Today on Weather Break, Dr. Schrage takes a look back at that old system and finds that meteorologists still use most of these codes to communicate today.

LINKS:

This table summarizes the 100 most common codes meteorologists use to describe the present weather.  To describe any given weather feature, find it on the table, and then add the numbers on each row and column.  For example, “lightning visible but thunder not heard” is code 13.

To see some examples of coded communications between National Weather Service offices, go to this web page.  Many of the products linked here are in strange codes.

If you want to annoy a meteorologist, ask him or her a question about stars, nebulae, comets, galaxies, or some other astronomy topic. It’s very common for people to assume that meteorologists study things like this – especially since the word “meteor” is in “meteorology”. So what’s the connection between the word “meteor” (as in the chunks of rock or metal that fall from the sky) and “meteorology” (the science of forecasting the weather)? As you’ll hear in today’s episode of Weather Break, even professional meteorologists often don’t know.

LINKS

A rough etymology of the word “meteorology” can be found here or here.  Thisis quite interesting, on the odd chance that you find yourself needing to hire a forensic meteorologist (it could happen).

In one form or another, the National Weather Service has been around for over 135 years now.  Originally part of the War Department’s Signal Corps, the first meteorologists of the NWS issued their first forecast on November 1, 1870.   When you read the forecast, it doesn’t sound much like the forecasts that you see on TV or hear on the radio today, which just goes to show how many changes have been made in the technology of weather forecasting and in the art of communicating forecasts.  On today’s episode of Weather Break, we take a look at the first forecast ever issued by the fledgling Weather Service to see what we can learn from this early attempt at weather prediction.

LINKS

For more information about the history of the National Weather Service, click here.

Every day on the show we say that the program is from the Creighton University Department of Atmospheric Sciences, but actually for the last few months the program has been coming to you from the Institute for Geophysics and Meteorology at the University of Cologne in Cologne, Germany, where Dr. Jon Schrage has been working.  He’s back at Creighton now, but his is just the latest in a series of exciting international experiences that students and faculty members in the meteorology program have enjoyed in recent years.  The global nature of studies of meteorology and climate open up wonderful opportunities for international travel, as discussed on today’s episode of Weather Break.

LINKS:

Many thanks to all our friends at the Institute for Geophysics and Meteorologyat the University of Cologne for all their support this summer.

A few years ago, we aired a couple of episodes of Weather Break about Beth Dickey’s work in Senegal:  Episode 149 and Episode 150.

We also had an episode about Anastasia Yanchilina’s work on a tropical island in the Pacific:  Episode 192.

Learn more about Andy Rudersdorf’s research on a vessel at sea in the Atlantic from Episode 12.

Creighton student Halley Holmes talked about her studies in Ireland in Episode 39.

Forensic meteorology is a subdiscipline within the Atmospheric Sciences.  It’s the science of reconstructing weather conditions at a particular location at a particular time.  The work of forensic meteorologists is often needed to establish certain facts in court cases, for example.  The meteorologist can testify as an expert about weather conditions that are relevant to the case and can even help determine the outcome of the trial.  On today’s episode of Weather Break, we learn more about careers in forensic meteorology and the kind of work that these scientists do.

LINKS

For more information about forensic meteorology, we recommend forensic-weather.com, Accuweather or Wikipedia.

For more information about careers in meteorology, we always recommend starting with this document provided by the American Meteorological Society.

Today the folks behind Weather Break are celebrating the 800th episode of the program by looking beyond the traditional limits of our topics — the weather and the climate of the Earth — and examining the possible climate of one of the new, so-called exoplanets that has been discovered in recent months. Gliese 581g made headlines around the world when its discovery was announced a few months ago because it is believed to be the most Earth-like planet yet found outside of our solar system. However “Earth-like” this new world may be, its atmosphere and its climate are undoubtedly very different from what we have here on Earth due to the fact that one side of the planet always faces its star and the other side is in perpetual darkness and cold. What does that mean for the weather and climate of Gliese 581g? Tune in to today’s episode of Weather Break to find out!

Links

Here are some examples of webpages with news about the discovery of Gliese 581g:

• NASA
• Huffington Post
• Wired
• The Guardian

Lately, in much of Nebraska and South Dakota the difference between the daily high temperature and the daily low temperature has been unusually large– something like forty degrees Fahrenheit, whereas something more like twenty-five degrees would be more expected. The reasons for the unusually high temperatures in the afternoons (and, to a lesser extent the low temperatures overnight) are somewhat complicated, but one key factor has been the extremely dry air that has been established over this part of the country for the last few weeks. What does humidity have to do with either the overnight low temperatures or the afternoon highs? Tune in to learn more about this and other factors that influence the diurnal temperature range.

Links

Actually, the article on Wikipedia about the diurnal temperature range is not bad at all.

For accurate forecasts in your area, we always recommend Unisys Weather.

Earlier this month, the strongest tropical cyclone of 2010 hit the island-nation of the Philippines. This storm was officially known as Super Typhoon Megi. Typhoons are the same kind of weather systems as hurricanes, and typhoons in the Western Pacific get names, just like hurricanes in the Atlantic do. However, if you heard about this particular typhoon on the news, you might have noticed that it was actually going by two different names — Megi, and “Juan”. How did this come to pass– how did it happen that one storm somehow ended up with two completely different names? This never happens for hurricanes and tropical storms in the Atlantic, but as we’ll hear on today’s episode of Weather Break, this actually happens fairly often for storms in the Western Pacific.

Links

For more information about Super Typhoon Megi/Juan, visit these news websites:

• AHN
• The Standard
• Reuters
• Catholic News Agency
• Global Times

When you dust your furniture, have you ever wondered where all that dust came from? Well, indoors and in our part of the world, most of what you find is lint and dirt and pet dander, but a certain amount of what’s there came from far away locations. The single largest source of dust for the atmosphere is actually the Sahara Desert. While the Sahara is overall a pretty dusty place, there are a couple of individual parts of the desert that are particularly dusty, and the most impressive of these is the so-called Bodele Depression in Chad. The Bodele Depression is commonly referred to as the dustiest place on Earth, and with good reason. A combination of particularly loose, silty soils and unusually strong winds means that a surprisingly large chunk of all of the dust in the atmosphere comes from this one little part of North Africa. Why is the Bodele Depression so dusty and windy? Tune in to today’s episode of Weather Break to find out!

Links

For more information about the Bodele Depression, visit:

• this article
• NASA
• Oxford
• National Academy of Science
• Wikipedia

Picture the Sahara Desert in your mind — shifting dunes of sand, extremely high daytime temperatures, and virtually no plant life whatsoever. Now for a surprise — it hasn’t always been that way. As recently as about five thousand years ago, the area now covered by the Sahara Desert was a lush, green savannah. Lakes as big or bigger than the Great Lakes were scattered around the continent, and giraffes and elephants roamed. What happened? How did a grassland turn into one of the driest places on earth? That’s a topic for the subdiscipline known as paleoclimatology, and we learn a little bit more about this on today’s episode of Weather Break.

Links

For more information about various “green Sahara” wet periods, check out these websites:

• National Geographic
• Wise Geek
• Science Daily

For more information about paleoclimatology, visit:

• NOAA
• NASA
• Science Daily

As we’ve discussed a couple of times over the years here on the program, there are actually a lot of different ways that fog can form in the atmosphere. All of these different methods of fog formation ultimately are about taking air that is unsaturated and bringing it to saturation so that condensation and formation of tiny droplets of liquid water begins, but there is a surprisingly large number of ways to make that saturation happen.  One of these is what is sometimes called hail fog.  As cold hailstones sit on the ground after a severe thunderstorm, they chill the air near the surface and, under the right conditions, form fog.  How common is fog like this, and what does it look like in comparison to other types of fog?  Tune it to today’s episode of Weather Break to find out!

Links

To see some impressive videos of hail fog, click here.  This is pretty interesting, too.

Here are some very nice pictures of hail fog.

Hurricane season in the Atlantic is winding down for 2010, and it turned out to be a surprisingly active year for these storms. As of the writing of this episode of the program about a week about, there had been sixteen named storms in the Atlantic, which is well above average. The latest of these storms was Hurricane Paula, and that storm turned out to have a particularly unusual track. Weather enthusiasts know that most hurricanes move from east to west due to the influence of the trade winds, which steer the storms as they move across the Atlantic. However, Hurricane Paula is a good example of a storm that moves the wrong way– she tracked from west to east! As you’ll learn on today’s episode of Weather Break, this isn’t particularly rare at this time of year as the seasons change and wind patterns adjust to the changing temperature patterns around the globe.

Links

For more information about Hurricane Paula, visit:

• Google News
• Dawn.com
• Nola.com
• Unisys Weather

So far this week, here on the radio program we have been talking about the different processes that the atmosphere can use to transport stuff around the Earth/Atmosphere system. That “stuff” could be materials like moisture, dust, or pollen, or it could be more abstract properties like spin or temperature. Today we wrap up our conversation about the transport of materials in the atmosphere by talking about diffusion. Diffusion isn’t a very effective way to move materials and properties around the atmosphere if the distances are large — you can’t diffuse a warm air mass north towards the poles, for example — but it turns out that diffusion is very efficient and effective at moving materials very short distances (like less than an inch or so). Are there really meaningful examples in the atmosphere where a transport of moisture or heat or whatever over such a short distance actually matters? Yes, and you’ll learn all about these situations on today’s episode of Weather Break!

Links

For more information about diffusion in the atmosphere, check out these websites:

• This paper
• This animation
• This even better animation
• Wikipedia

For the next few days here on Weather Break, we’re going to be talking about how stuff gets moved around (or “transported”) in the atmosphere.  It turns out that transporting stuff — be that heat or moisture or whatever — around the planet is fundamental what the atmosphere is DOING, and therefore the atmosphere has several processes that it can use to accomplish this.  Yesterday we started off by talking about the simplest of these processes– advection, which is just transporting something by moving the air that that something is in.  Technically, “advection” is only the horizontal transport of materials and properties; the vertical transport is more accurately called “convection”.   Since the source of most of the important properties in the atmosphere — like heat and moisture — is near the surface of the Earth, vertical transport is hugely important in meteorology.  The best example of convection in the atmosphere turns out to be thunderstorms; in fact, meteorologists often use the terms “convection” and “thunderstorms” interchangeably.  How are thunderstorms an example of a vertical transport of material in the atmosphere.  Tune in to today’s episode of Weather Break to find out!

Links

For more information about convection, check out these links:

• UCAR
• Reach Out Michigan
• Wikipedia

For the next few days here on Weather Break, we’re going to be talking about how stuff gets moved around (or “transported”) in the atmosphere.  It turns out that transporting stuff — be that heat or moisture or whatever — around the planet is fundamental what the atmosphere is DOING, and therefore the atmosphere has several processes that it can use to accomplish this.  Today we start off by talking about the simplest of these processes– advection.  Advection is just transporting something by moving the air that that something is in.  Moving moist air to a location where the air is currently dry, for example, would constitute “moisture advection”.  To learn more about how advection works and the role it plays in the earth/atmosphere system, tune in to today’s episode of Weather Break.

Links

For more information about advection, check out these links:

• The University of Illinois
• The Glossary of Meteorology
• eNotes
• Wikipedia

The weather this fall has been amazing in much of Nebraska and South Dakota, but frankly we could use a little bit of rain.  This isn’t because the rain could do the crops any good at this time of the year — the issue has to do with the crops NEXT summer.  Why is rain in the autumn good for corn and soybeans that won’t even be planted for another six months?  Tune in to today’s episode of Weather Break for all the answers!

Links

For reliable forecasts, we always recommend Unisys Weather.

For information about current soil moisture conditions, check out this page.

It’s not everyday that meteorologists get a whole new platform for observing the atmosphere–heck, most days we’re happy if more or less all of the existing systems (like weather balloons, radars, and satellites) are all working. However, a new system for getting realtime observations of the conditions near the base of hurricanes has been invented. This system relies on a network of tethered blimps known as “aeroclippers”, and, as Creighton University student Jeff Hamilton reports, these blimps have the potential to revolutionize our ability to forecast hurricanes and other weather systems at sea.

LINKS:

Most of the available information online about the Aeroclipper Blimps is pretty technical, but you might find these sites interesting:  1 2 3 4…

Weather Break’s special coverage of technology and high impact weather is made possible through the financial support of the NASA Nebraska Space Grant.

For anywhere between $30 and a few thousand dollars, anyone can set up a backyard weather station to monitor the weather and climate of their neighborhood.  Lots of people have simple systems like rain gages, but a real weather enthusiast might have wind vanes and anemometers and barometers.  On today’s episode of Weather Break, Dr. Jon Schrage takes a look at some of the technology available to the public for those who are eager to keep track of their own weather data and observations.

LINKS:

For more information about backyard weather stations, follow these links:

http://www.scientificsales.com/?gclid=CPTniO_D4pwCFRHxDAodWDHGJQ

http://www.ambientweather.com/homes.html

http://www.washingtonpost.com/wp-dyn/articles/A15926-2004Nov27.html

Since Weather Break originates on the campus of Jesuit university, from time to time we like to take the opportunity to mention some of the contributions made by Jesuits to the field of meteorology. Today we turn our attention to Father Benito Viñes, who was known as “Father Hurricane” in his lifetime. He was the director of a meteorological center in Cuba in the late 1800s, and his insights into the use of weather information relayed by telegraph revolutionized our understanding of hurricane motion and the prediction of hurricane tracks.

LINKS:

Here is an interesting online biography of Father Viñes.  There also has been an article about him in Weatherwise.

In the past on Weather Break, we’ve talked about two different ways to try to understand the nature of the atmosphere:  the mythology of the ancient Greeks, and the rational attempts to understand the world through philosophy.  Inspired by these lines of thought, today on Weather Break Dr. Jon Schrage takes a look at our modern understanding of the nature of air itself–what air is, how it behaves, and how the properties of air add up to weather and climate.

LINKS

Here are some resources about the basic nature of air:

• http://www.hearlihy.com/content/item.aspx?CategoryID=33&ap=2&art=18&bhcp=1
• http://en.wikipedia.org/wiki/Air
• http://www.classbrain.com/artaskcb/publish/article_30.shtml

Water freezes at 32 degrees Fahrenheit, right?  Well, maybe.  Ice definitely MELTS at 32 degrees, but the exact temperature at which liquid water freezes depends on the trace impurities in the water.  Something like an ice cube trays contains a very large number of water molecules, so it’s almost inevitable that there were be SOME impurities that will help the water freeze at a relatively high temperature, but cloud droplets are extremely small and almost certainly do NOT contain the necessary impurities.  As a consequence, liquid water droplets in a cloud typically exist in a form known as “supercooled water” — water that remains a liquid at temperatures far below 32 degrees F.  How does this happen, and what does it mean with regard to what’s going on inside of the cloud?  Tune in to today’s episode of Weather Break to learn more!

Links

For more information about supercooled water, visit:

• WikiHow
• Argonne National Lab
• The University of Illinois

While larger hailstones certainly do exist, the vast majority of the hail that falls from thunderstorms comes in the form of relatively small chunks of ice — rarely bigger than a golf ball.  As it happens, there have been a couple of incidents lately in which extremely large hailstones have been reported — in one case, the largest of the hailstones weighed nearly two pounds!  Just how large IS the world’s largest hailstone, and how does hail form, anyway?  Tune it to today’s episode of Weather Break for all the answers!

Links

For more information about the record-breaking hailstone in Kansas, visit:

• KAKE
• Oklahoma Skies

For more information about the record-breaking hailstone in South Dakota, visit:

• WEWS
• This blog

For years, you’ve been hearing the folks here at Weather Break talk about “relative humidity”.  You hear them mention the concept on The Weather Channel, NOAA Weather Radio, or any of the other sources of weather information that you may be using on a daily basis.  Isn’t it time to really understand what is meant by the term?  If so, tune in to today’s episode of Weather Break for all the answers!

Links

For more information about “relative humidity”, visit:

• How Stuff Works
• USAToday
• The Glossary of Meteorology
• Engineering Tool Box

For current maps of the relative humidity, try this site.

The climate of the so-called “Antarctic Dry Valleys” is like no-place else on Earth — quite literally, the climate of these places is actually more like that of Mars than of, say, Nebraska and South Dakota.  On today’s episode of Weather Break, Dr. Jon Schrage of the Creighton University Department of Atmospheric Sciences talks about these strange locations, where the winds howl at more than 150 miles per hour and snow almost never falls.

Links

For more information about the Antarctic Dry Valleys, consider these sources:

• McMurdo Dry Valleys Official Site
• Wikipedia
• Antarctic Connection

For more information about NASA’s interest in these valleys, visit:

• NASA
• Image of the Day
• Astrobiology.com

At this time of year, you will often see that your local meteorologists are informing you that the National Weather Service has issued a “Frost Warning” or a “Freeze Warning” or a “Freeze Advisory” or some similar kind of statement.  These messages are intended primarily for agribusiness and horticulture purposes, as a cold night like the one that is expected will apparently bring about an end to the growing season.  In November, this can be a pretty tricky forecast, but in January or February, it would be a LOT easier to figure out whether or not it was going to freeze (almost certainly, the answer would be “yes”).  Why doesn’t the National Weather Service issue frost and freezes warnings in the winter?  We asked meteorologist Steve Byrd, and he tells us all about it on today’s episode of Weather Break.

Links

WeatherBug provides this relatively informal definition of “Frost and Freeze Warnings”.

Yesterday on Weather Break, we started talking about the “diurnal” (or “daily”) cycle of temperature at the surface of the earth. Obviously, most days have a fairly straightforward cycle of temperatures — it’s colder at night and warmer in the afternoon. But a good question is exactly WHEN the warmest temperature of the day is observed. On today’s episode of Weather Break, we talk about the gains and losses of heat that determine the temperature at the surface of the earth and use that information to figure out WHEN we should expect to observe the “daytime high temperature”.

Links

For reliable forecasts, we recommend Unisys Weather.

Obviously, most days have a fairly straightforward cycle of temperatures — it’s colder at night and warmer in the afternoon. But a good question is exactly WHEN the very coldest temperature of the day is observed. On today’s episode of Weather Break, we talk about the gains and losses of heat that determine the temperature at the surface of the earth and use that information to figure out WHEN we should expect to observe the “overnight low temperature”.

Links

For reliable forecasts, we recommend Unisys Weather.

When precipitation particles like raindrops or snowflakes fall out of the bottom of a cloud, they have to cross the treacherous, subsaturated layer of air beneath the cloud, and, frankly, they often do not make it — they evaporate before hitting the ground. If what’s falling is liquid water, we call the phenomenon “virga”, but if it’s small ice crystals that are trying to reach the surface of the Earth, we call it an example of a “fall streak”. On today’s episode of Weather Break, Dr. Jon Schrage talks about what fall streaks look like and what their presence tells us about what is going on in the cloud and in the subcloud layer.

Links

There are lots of beautiful pictures of fall streaks on Google Images.

For more information about fall streaks, visit:

• The University of Illinois
• Accuweather

Probably everyone has heard the expression that something was “burning up in the atmosphere”.  It usually applies to stuff like satellites or comets that are falling to the surface of the Earth from space.  But WHY does this happen?  Does it have anything to do with the fact that these objects have to pass through the thermosphere– a layer of the atmosphere  where the temperature is hundreds or even thousands of degrees higher than what we normally expect at lower levels in the atmosphere?  Check out today’s episode of Weather Break for all the answers!

Links

For more information about the thermosphere, visit:

• Manchester Metropolitan University
• NASA
• The Atmosphere Guys

You might wonder WHY someone would want to do something like this, but an artist and an architect recently were able to create an example of an “indoor cloud” as part of an ongoing exhibition in Venice, Italy.  There’s no particular practical application for something like this, but images and videos from this indoor cloud have been circulating around the internet.  In addition to being an impressive technical feat, the creation of this particular indoor cloud was accomplished using processes quite similar to how real clouds form in the atmosphere, as Dr. Jon Schrage discusses on today’s episode of Weather Break.

Links

This is where we originally found a story about the indoor cloud.  Follow the links provided on that page for more information.

All this week here on Weather Break, we have been talking about the different kinds of floods that are experienced in Nebraska and South Dakota. All of the kinds of floods that we have discussed clearly had one thing in common — they were all caused by the weather. That being said, there are a couple of different ways in which flooding can occur on a sunny day; these are floods that are NOT (at least DIRECTLY) caused by storms and heavy rainfall. Examples of these kinds of floods include dam failures and the rapid melting of a mountain glacier during a volcano. On today’s episode of Weather Break, we talk about these and other types of “nonmeteorological” floods.

Links

Here is a news article about the flooding associated with that dam failure in Iowa.

For more information about the different kinds of floods, visit the National Weather Service. Younger listeners might prefer the FEMA For Kids website.

For information about how to prepare for a flood, visit this page on Ready.gov.

All this week here on Weather Break, we have been talking about the different kinds of floods that are experienced in Nebraska and South Dakota. Today on the program, we turn to a kind of flood that is not possible in our part of the country — namely, storm surges. Storm surge is the rise in sea level associated with the landfall of a hurricane or tropical storm. These kinds of floods are obviously not possible around here, but they are a serious concern for folks living along the Gulf Coast of the United States, for example. On today’s episode of Weather Break, we will talk about the processes that cause storm surge and why this type of flooding tends to be the most expensive part of a hurricane’s damage.

Links

For more information about storm surge, visit:

• the National Hurricane Center
• the University of Illinois
• USAToday
• Wikipedia

For more information about the different kinds of floods, visit the National Weather Service. Younger listeners might prefer the FEMA For Kids website.

For information about how to prepare for a flood, visit this page on Ready.gov.

Most of the Weather Break listening area is in Nebraska and South Dakota, and admittedly these are not particularly “urban” parts of the country. That being said, however, it should still be pointed out that the dangers of what is known as “urban flooding” are very real — you don’t have to be in a major metropolitan area to experience urban floods. Rather, this kind of flood happens whenever garbage or little accumulates in storm drains and sewers, blocking them and making them ineffective at carrying water off of city streets when heavy rain falls. On today’s episode of Weather Break, we take a look at the causes and impacts of urban flooding and the challenges that it brings to forecasters at the National Weather Service.

Links

For more information about urban flooding, visit:

• Floodsite.net
• DHI
• The US Geological Survey

For more information about the different kinds of floods, visit the National Weather Service. Younger listeners might prefer the FEMA For Kids website.

For information about how to prepare for a flood, visit this page on Ready.gov.

Yesterday on Weather Break we kicked off what we are calling “Flood Week” here on the program.  We started off talking about the kinds of widespread floods that happen very slowly over large areas.  These kinds of floods give people plenty of time to evacuate to higher ground — they may even be forecasted far enough in advance that the authorities can work on setting up walls of sandbags to help mitigate damage.  In contrast, flash floods happen with little or no warning, making them a significant challenge for forecasters with the National Weather Service.  On today’s episode of Weather Break, we take a look at the different kinds of conditions under which flash floods can happen and the kinds of things you can do to stay safe when flash floods are likely.

Links

For more specific information about flash floods, visit weather.gov, FEMA, or this site with current forecasts.

For more information about the different kinds of floods, visit the National Weather Service. Younger listeners might prefer the FEMA For Kids website.

For information about how to prepare for a flood, visit this page on Ready.gov.

Flooding is widely recognized as the deadliest of the severe weather phenomena.  Over the years here on the program, we’ve had quite a few episodes about some specific flooding events.  Most of these events were  examples of floods that were caused by prolonged periods of heavy rain over a large area.  That almost seems like a silly thing to say — I mean, at first glance you might wonder what ELSE a flood could be. Well, actually, this week on Weather Break we’re taking a look at the different kinds of floods that can happen. Weather professionals known as hydrologists study and forecast floods, and they know that these tragedies for lots of different reasons, as we’ll hear on today’s episode of Weather Break.

Links

For more information about the different kinds of floods, visit the National Weather Service. Younger listeners might prefer the FEMA For Kids website.

For information about how to prepare for a flood, visit this page on Ready.gov.

“Water water everywhere nor any drop to drink” complained a group of sailors stranded at sea in Samuel Taylor Coleridge’s “Rhyme of the Ancient Mariner”.  In the poem, the sailors had run out of fresh drinking water, and so despite being surrounded by water, they were dying of thirst.  That’s, of course, because sea water is salty–far too salty to be drinkable.  Interestingly, however, from the point of view of the atmosphere, there really isn’t any difference between fresh water and sea water.  All of the important ways in which the atmosphere and bodies of water interact work the same for freshwater lakes and inland seas as they do for the open ocean.  On today’s episode of Weather Break, we take a look at some of the roles saltwater plays in the atmosphere.

LINKS

For the full text of the “Rhyme of the Ancient Mariner”, click here.

For more information about the topics of haze and aerosols in the atmosphere, we recommend these past episodes of Weather Break:

• The Differences between Haze and Fog
• Global Dimming

In the past on Weather Break, we talked about the challenges associated with forecasting how the oil slick in the Gulf of Mexico will move.  We also mentioned that, once upon a time, meteorologists and atmospheric scientists actually considered deliberately spilling tanks of oil in front of approaching hurricanes in an attempt to weaken the storms before landfall.  For a number of reasons (that will be discussed on tomorrow’s episode of the program), the idea was never tried and probably wouldn’t have worked.  However, the idea was part of the brainstorming that went on behind the scenes at Project Stormfury, the government’s attempt to find ways to reduce the impact of hurricanes back in the 1950s and 60s.  In the era of rockets and nuclear bombs, it only seemed reasonable that man should be able to even control the weather with technology, so the scientists at Project Stormfury set out to figure out what could be done to weaken storms even a little bit.  Since these days we don’t even TRY to weaken hurricanes, you can probably guess that apparently these techniques weren’t very successful.  However, there is one important legacy of Project Stormfury that continues to this day–hurricane hunting.  Learn how this important field activity has saved lives on this episode of Weather Break.

LINKS

For more information about Project Stormfury, we recommend NOAA, the USA Today, this article,  or Wikipedia.

There is an awful lot of information online about hurricane hunting… we recommend starting your research with this Google Search on the term “hurricane hunters”.

Here on Weather Break, we are guilty of sometimes focusing on the most dramatic aspects of weather, forgetting that the “little things” of life can be changed dramatically by the weather.  This week we’ve been talking with tropical meteorologist Brian Strahl about his experiences during the 2004 hurricane season.  His home in Orlando, Florida was hit by an unprecedented three hurricanes that year.  Today he tells us a little bit about how the hurricanes frustrated his efforts to set up his new home in Orlando.  He also talks about how Walt Disney World faired during the storms.

LINKS:

Here’s an interesting story about a family’s experiences at Walt Disney World during Hurricane Charley.

According to this article (which I’m not entirely sure is correct), Walt Disney World had, in fact, closed twice before Hurricane Charley struck.

Then Disney had to deal with Frances.  And then Jeanne.

Yesterday on Weather Break, we spoke with tropical meteorologist Brian Strahl about his experiences in Orlando, Florida during the 2004 hurricane season.  Within about a six-week period in the fall of 2004, Orlando was hit by an unprecedented THREE hurricanes.  The worst of these was Hurricane Charley, but both Hurricane Frances and Hurricane Jeanne brought huge amounts of rain and strong winds to the area.  In today’s episode, we continue the conversation with Brian.  He discusses the impact Frances and Jeanne had on the Orlando area, as well as ways in which the community’s experiences with Hurricane Charley influenced their responses to these two later storms.

LINKS:

Here is Wikipedia’s article on Hurricane Frances.  Here is the official track of the storm, as provided by Unisys Weather.

Here is Wikipedia’s article on Hurricane Jeanne.  Here is the official track of the storm, as provided by Unisys Weather.

Here is a map with all of the tracks from the hurricanes and tropical storms in the 2004 hurricane season.  Doesn’t central Florida look like a great place to be?

Is it good for the housing market when there are so many hurricanes in one area?  Not really.

Don’t buy into the urban legend that these hurricanes were sent by God to punish parts of Florida that voted for George W. Bush in the 2000 election.

This article pretty much sums up how Florida felt after the 2004 hurricane season.

Today Weather Break kicks off a series of three episodes based on a telephone interview with tropical meteorologist Brian Strahl.  Brian moved to Orlando, Florida in the fall of 2004, just in time to have his new home get hit by THREE hurricanes in one year.  In today’s episode, Brian talks about his experiences with the worst of the three storms, Hurricane Charley.

LINKS:

Does Wikipedia have the facts on Hurricane Charley?  Sure it does.

Does Unisys Weather have a good map of Hurricane Charley’s path?  Sure it does.  In fact, they also have a great map with the tracks of all of the hurricanes and tropical storms from the 2004 hurricane season.  You’ll notice that three of those tracks cross central Florida.

Here is an interesting gallery of pictures and videos from Hurricane Charley.

Some studies show that the rates of traffic accidents go up around the country in mid September, and the main reason this happens is because of the increasing problem of sun glare on windshields.  The exact location along the eastern horizon where the sun rises each morning varies over the course of the year, and in mid September sunrise happens exactly due east.  Since most roads run on a north-south-east-west grid, that means that a lot of drivers end up having the sun right in their eyes during their morning commute.  On today’s episode of Weather Break, we talking about why the sun is in the eyes of drivers this time of year and some basic safety tips to make your commute safer.

Links

Related Episodes

• Winter Roadside Emergency Preparedness
• Sun Safety

As we discussed yesterday on the program, air is made of a mixture of gases.  But even the trace gases are vastly more abundant than hydrogen and helium are — hydrogen and helium are basically nonexistent in Earth’s atmosphere.  Today on Weather Break, we find out that the rest for this has to do with the way temperature effects the speed of molecules of gases.  Light gases like hydrogen and helium end up having mean molecular speeds that are extremely fast — faster than the escape velocity of the Earth, actually.  What this means for the atmospheres are planets other than the Earth is also discussed on this episode of the program.

Links

I really like the “Periodic Table Blog” on Slate.com.  Here are the entries for Hydrogen and Helium.

For more information about the gases of the early atmosphere, visit:

• Science Magazine
• The University of Colorado
• WikiAnswers

Related Episodes

• Hydrogen
• Helium
• The Origin of the Atmosphere

Air is made of a mixture of gases.  Some of these gases are very abundant, like nitrogen and oxygen.  Other gases are trace gases, like methane or ozone or nitrous oxide.  But even these trace gases are vastly more abundant than hydrogen and helium are — hydrogen and helium are basically nonexistent in Earth’s atmosphere.  That’s particularly puzzling when you realize that these are by far the most plentiful elements in the universe.  How did it come to pass that Earth’s atmosphere lacks two materials that are pretty much everywhere else in the universe?  On today’s episode of Weather Break, we start explaining what happened to all the hydrogen and helium that was originally in our atmosphere.

Links

I really like the “Periodic Table Blog” on Slate.com.  Here are the entries for Hydrogen and Helium.

For more information about the gases of the early atmosphere, visit:

• Science Magazine
• The University of Colorado
• WikiAnswers

Related Episodes

• Hydrogen
• Helium
• The Origin of the Atmosphere

With a long, hot summer finally over, the Weather Break listening area is finally starting to see some hints of Fall weather.  Over the last few days, there have been a few crisp, cool mornings, which were very refreshing after the awful, muggy mornings of mid to late August.  What happens in September that brings about these changes in the weather patterns?  Tune in to today’s episode of Weather Break to find out!

Links

For reliable weather forecasts, we always recommend Unisys Weather.

Related Episodes

• Frost and Freeze Warnings in the Fall
• Frost in Low-Lying Areas
• The October 1997 Snowstorm in Nebraska

Over the weekend, Hurricane Earl nearly swiped the eastern coast of the US — the part of the country with generally the highest population density. For a period of time, it looked like the storm might make landfall on Long Island, NY. That’s a nightmare scenario for forecasters, as the major metropolitan areas of the US are generally NOT well prepared for a hurricane. It means that good forecasts are particularly important, but that’s tricky.  What kinds of factors are meteorologists looking for when they want to make forecasts of a hurricane’s track?  Check out today’s episode of Weather Break for some of the answers!

Links

For the latest information about Hurricane Earl, try this Google News Search on the term “Hurricane Earl”.

For more information about hurricane track prediction, visit:

• National Hurricane Center
• HurricaneTrack.com
• Science Daily

Related Episodes

• Tropical Storm Zeta
• Tropical Storm Grace
• The Only Known Tropical Storm in 1914

A barometer is a very technical piece of weather equipment that is used to measure air pressure.  An official mercury barometer costs hundreds or even thousands of dollars, yet the principles on which it is based are quite straightforward– in fact, they are EXACTLY the same principles that form the basis of how a drinking straw works.  When you drink from a straw, you are really just creating a small barometer between the cup and your lips.  To understand how this works, check out today’s episode of Weather Break!

Links

For more information about how a barometer works, visit these sources:

• USA TODAY
• Science Company
• About.com
• ehow.com
• explainthatstuff.com

Related Episodes

• Backyard Weather Stations
• Big Changes in the Weather

From the point of view of the public, one of the really interesting things about hurricane season is the way hurricanes are assigned names, like “Andrew”, “Alex”, or whatever.  The World Meteorological Organization maintains lists of names that are used for this purpose in each of the ocean basins where hurricanes and tropical storm occur.  The lists are only so long, so over a period of six years the names get reused.  However, if a particular hurricane is unusually destructive, it’s name can be permanently removed from the lists, guaranteeing that there will never be another hurricane named, say, “Katrina”.  How is this done, and what letter of the alphabet has seen the most retirements?  Tune in to today’s episode of Weather Break to find out!

Links

For a complete list of all retired hurricane names for the Atlantic basin, click here.

Related Episodes:

• Strangely-Named Hurricanes
• The Naming of Hurricanes

As part of Weather Break’s ongoing coverage of ways in which climate and climate change figure into some of the struggles going on in various parts of the world, today we are taking a look at the challenges facing the indigenous people of some of the small, low-lying islands of the world.  As Global Warming increases, the expected increase in sea level will mean that these islands are no longer safe places to live, and ultimately they will need to be evacuated.  In the case of the island nation of Tuvalu, initially New Zealand had offered to accept most of its 11,000 residents as refugees.  However, as anti-immigrant sentiments grew in New Zealand, that country eventually restricted the number of Tuvaluans who could seek refuge there to a mere 75 per year.  If such a small number of environmental refugees are already resulting in potentially serious diplomatic problems between nations, one can only fear the coming time when rising sea levels may mean the relocation of millions of other coastal residents around the world.

LINKS:

For more information about the plights of people and ethnic groups that are forced to evacuate low-lying islands because of climate change, we recommend the following websites:

• http://www.csa.com/discoveryguides/refugee/review5.php
• http://www.loe.org/shows/segments.htm?programID=06-P13-00013&segmentID=6
• http://www.humanrights-geneva.info/Tuvalu-s-climate-change-refugees,2905

Where in the world is Tuvalu?
Where in the world is Vanuatu?
Where in the world are the Maldives?

Related Episodes:

• Our complete collection of episodes about “Climate and Conflict”.

Recently on Weather Break, we inaugurated a new series of episodes that we are calling “Climate and Conflict”.  From time to time here on our show, we’re going to be talking about the ways in which climate and climate change relate to past and ongoing disputes between nations.  Today we’re looking into the complex and often contentious relationships between Iraq, Syria and Turkey.  Iraq sits in Mesopotamia, one of the early Cradles of Civilization due to the flow of the Tigris and Euphrates rivers through the deserts of that country.  These rivers are essential to the people of Iraq–not only for drinking water but also for irrigation and the production of food.  However, Iraq is what is known as a “downstream country”, at the mercy of the “upstream countries” (namely Syria and Turkey) that have built many dams and other civil engineering projects to divert the waters of these rivers for their own uses.  Several times in recent decades, serious conflicts have broken out between Iraq and Turkey due to Turkey’s unwillingness to provide the Iraqi people with the water they need.  A current drought in Turkey is only amplifying these tensions, as seen on today’s episode of Weather Break.

LINKS:

NPR recently aired an interesting program about how drought in Turkey and restricted flows in the Tigris and Euphrates rivers has severely restricted the rice harvest in Iraq.  Fortunately, Turkey appears to be willing to avoid a crisisby agreeing to release more water to Iraq.

As this Google search shows, the conflicts over water rights in that part of the world are complicated and well-documented.

Related Episodes:

• Our complete collection of episodes about “Climate and Conflict”.

Today on Weather Break we are kicking off a new series of episodes that we are calling “Climate and Conflict”.  From time to time here on the show, we’re going to be taking a look at the ways climate and climate change factor into disputes going on around the world.  Most of these conflicts are about water, which can be a particularly difficult problem in parts of the world where the populations are dependent on rivers that flow across international boundaries.  As the climate of the world shifts due to natural and man-made forcings, some marginal climate zones may no longer be able to support their current populations, potentially creating humanitarian crises as waves of “environmental refugees” overwhelm the resources of other regions.

LINKS:

You can find an excellent summary of concerns about climate change and its role in international conflicts on the website of the International Crisis Group.  That report makes frequent reference to the so-called Stern report, which addresses the troubling economics of climate change.

Related Episodes:

• Our complete collection of episodes about “Climate and Conflict”.

A name like “Fifi” seems more appropriate for a small dog than for a major natural disaster, but Hurricane Fifi was a storm that the people of Central America are unlikely to ever forget.  On this date in 1974, Fifi came ashore in Honduras as a modest Category 2 hurricane.  However, while the winds of this storm weren’t particularly severe, the storm itself managed to dump as much as two feet of rain in some parts of that mountainous country.  Somewhere between 5,000 and 10,000 people died in the resulting flash flooding, making Fifi one of the deadliest hurricanes ever in the Atlantic.  As awful as the storm was, it also had several more surprises in store for the poor forecasters of that time, as you’ll hear in today’s episode of Weather Break.

LINKS:

For more information about Hurricane Fifi, we recommend Weather Underground, Time, World Book, Wikipedia, or Super70s.com. For more technical information, consider these articles.

Related Episodes:

• Our collection of episodes about Hurricane Rita
• Our collection of episodes about Hurricane Ike
• Our collection of episodes about the three hurricanes that hit Orlando in 2004

In the United States, the primary federal agency charged with monitoring and forecasting the weather is, of course, the National Weather Service.  The NWS is ultimately under the jurisdiction of the Department of Commerce, which actually tells us something about how the government perceives the significance of weather–they mainly see it as a factor influencing commerce and transportation.  As it happens, just about every country on Earth operates its own meteorological services agency, but different countries do so to meet different needs.  On today’s episode of Weather Break, we take a look at some of the national meteorological services around the world and try to decipher why even the poorest of countries spend so much time and effort trying to predict the weather.

LINKS

Here is a fairly comprehensive list of all the national meteorological services of the world.

Related Episodes

• Meteorology:  A Gateway to the World
• How’s the Weather… In Malin Head, Ireland?
• A Creighton Student Travels to Africa to Study the Monsoon, Part 1
• A Creighton Student Travels to Africa to Study the Monsoon, Part 2

To say the very least, the last few years have been very tumultuous in the markets.   Each day, no one seems to know whether stocks will go up or go down.  Several times now we’ve heard commentators and pundits on the news say that predicting the markets right now is like predicting the weather.  Here at Weather Break, we suppose that they are trying to say that the markets are behaving unpredictably, although, of course, meteorologists make pretty good forecasts of the weather all the time!  In fact, not only is the weather somewhat predictable, but actually its variability is part of the rationale behind the establishment of the markets that trade what used be called “weather derivatives”–or, more accurately, “weather coverage”.  There are plenty of companies out there from which you can buy contracts that only pay out if a particular event happens in the weather–something like an early frost or excessive rainfall.  One of these companies is called Weather Bill, and Dr. Jon Schrage of the Creighton University Department of Atmospheric Sciences recently spoke with Jeff Hamlin of that company about how these contracts work and why anyone would want to invest money in the weather.

LINKS:

Everyone here at Weather Break would like to thank Jeff Hamlin and Regina Sinsky of Weather Bill for all of their help with this episode of the program.  Use the “Quote and Buy” link on the Weather Bill website to work up a quote to see how much it would cost to purchase weather coverage that would meet your needs.

“Weather coverage” like that sold by Weather Bill is different from crop insurance, although both products are about hedging against the unexpected.

Companies like Weather Bill don’t particularly like the term “weather derivatives” to describe these contracts, although that term is actually pretty common in the news media. You can learn more about weather derivatives fromthe associated page on Wikipedia.

Related Episodes

• Weather and the Federal Budget
• Freeze/Thaw Cycles

In our part of the country, big changes in the weather usually mean that a “front” has passed through.  Meteorologists recognize five different kinds of fronts, each of which serves as the boundary between different combinations of types of air masses.  On today’s episode of Weather Break, we take this as an opportunity to talk about the different kinds of weather fronts and the types of weather that you might expect as these fronts pass your location.

LINKS

For maps showing the current locations of fronts, we recommend Unisys Weather.

We really like the description of cold fronts provided online by the University of Illinois.  They also have pages about warm fronts, stationary fronts, occluded fronts, and drylines.

Related Episodes

• Cold Fronts in the Summer
• Max Margules and the Slope of Fronts
• Stationary Fronts

Most of the interesting and severe weather that people care about is caused by rising motions in the atmosphere. Clouds, for example, are always regions where air is rising, and therefore so are thunderstorms and hurricanes and, well, pretty much anything exciting in the weather. On the other hand, in general the weather features associated with sinking motion in the atmosphere are less dramatic. That being said, sometimes sinking motion in the atmosphere IS severe and causes damage on the ground, and the best example of this is a weather phenomenon known as a microburst. Microbursts happen late in the lifetime of a thunderstorm, and on today’s episode of Weather Break, Dr. Jon Schrage talks about how the process of entrainment can create a violent, damaging downdraft like the ones that cause microbursts.

LINKS:

There are lots of dramatic videos showing microbursts on YouTube.  Rather than singling out specific videos, we’ll just redirect you to a YouTube search on the term “microburst”.

For a gallery of photos of microburst damage, do a Google Image Search on the term “microburst damage”.

For more, general information about microbursts, see about.com,  Wikipedia,NOAA, or USA Today.

Related Episodes

• Sinking Motion in the Atmosphere
• A Lonesome Place Against the Sky
• Haboobs

All this week on Weather Break, we have been talking about the few known weather or climate cycles.  For folks who were expecting to find out that there were hard-and-fast patterns to the weather, it was probably pretty disappointing — it turns out that even the known “patterns” and “cycles” in the atmosphere are just broad guidelines, with lots of variability within the features.  If you think about it, this is actually pretty surprising — after all, weather is fundamentally driven by the heating from the sun, and the amount of heat received at the surface is VERY cyclic, with clear daily and annual patterns?  If the stuff that DRIVES weather is so predictable and cyclic, why isn’t weather?  Tune in to today’s episode of Weather Break to find out!

Links

There are a lot of opinions out there about whether or not weather cycles and climate cycles exist.  Here are some links to folks with a range of opinions:

• Global Weather Cycles
• A. Jacobina Poulsen
• William James Burroughs
• Human Events
• Teacher’s Domain
• P. Laux
• Wikipedia
• Science Daily
• Roy Spencer

RELATED EPISODES

• Sir Gilbert Walker
• Fr. Jerome Ricard
• Changes in the Solar Output

All this week on Weather Break, we’re talking about some of the few known “cycles” or “oscillations” in weather and climate.  Today we turn to a feature of the atmosphere known as the North Atlantic Oscillation, or NAO.  Whereas some of the oscillations that we learned about earlier this week were sort of “opposites” of each other, the two phases of the NAO are more about slightly unusual configurations of two large air pressure centers that are typically found over the Atlantic ocean.  Relatively small shifts in the mean positions of these cyclones and anticyclones set up changes in the winds at the surface and substantial changes in the weather downstream over Europe.  The NAO also has implications for whether more hurricanes will strike the eastern coast of the United States or the Gulf of Mexico shoreline.  To learn more about the North Atlantic Oscillation, tune in to today’s episode of Weather Break!

Links

For more information about the North Atlantic Oscillation, visit:

• Columbia University
• The Climate Prediction Center
• Theodor Landscheidt

For more information about the Atlantic Multi-Decadal Oscillation, visit:

• NOAA
• Weather Underground
• NCAR

This week’s investigation of known examples of “weather cycles” or “climate cycles” continues today with the so-called Quasibiennial Oscillation, or QBO.  The QBO is one of the most poorly understood features of the atmosphere, despite the fact that it has been well-observed for more than 50 years.  It’s a 26-month cycle in the winds in the tropical stratosphere, and it turns out to have important implications for the long-range forecasts of hurricane activity in the Atlantic that you see at this time year.  To learn more about the QBO, tune in to today’s episode of Weather Break!

Links

For more information about the QBO, consult:

• The University of Arizona
• UCLA
• The Naval Research Labs
• The Glossary of Meteorology
• The University of Washington
• Wikipedia

Related Episodes

• Leon Teisserenc de Bort
• The Troposphere and the Stratosphere
• Where Weather Ends

All this week on Weather Break, we’re talking about weather and climate cycles.  In general, most professional meteorologists and climatologists are pretty skeptical about claims of discoveries of “cycles” or “patterns” in weather and climate, but a small number of these DO check out.  One important example of these would be the Southern Oscillation, better-known to the public by the names “El Nino” and “La Nina”.  These terms represent the extremes within a range of variability in the climate system of the tropical Pacific Ocean, and when these pattern set up, they persist for about a year before eventually reverting to more normal conditions.  On today’s episode of Weather Break, we take a look at the interpretation of the Southern Oscillation as an example of a climate cycle.

Links

One of the best sources of information about El Nino, La Nina and the Southern Oscillation is NOAA’s theme page.  NASA has a page oriented towards explaining the process to kids.

Wikipedia’s explanation isn’t terrible.

Related Episodes

• Is 2009 an El Nino Year?
• ENSO-Neutral Conditions
• Sir Gilbert Walker

You’ll often hear people talk about “weather cycles” — patterns of weather or climate that oscillate back and forth between two extremes — but do such cycles really exist in the atmosphere and the climate system?  All this week on Weather Break, we’re going to be taking a look at that question and seeing some of the “cycles” or “oscillations” that DO seem to be real.  What do these patterns tell us about the behavior of the atmosphere, and why aren’t there more of them?  Tune in to today’s episode of Weather Break to start to find out!

Links

There are a lot of opinions out there about whether or not weather cycles and climate cycles exist.  Here are some links to folks with a range of opinions:

• Global Weather Cycles
• A. Jacobina Poulsen
• William James Burroughs
• Human Events
• Teacher’s Domain
• P. Laux
• Wikipedia
• Science Daily
• Roy Spencer

Related Episodes

• Sir Gilbert Walker
• Fr. Jerome Ricard
• Changes in the Solar Output

In recent weeks, one of the main stories in the international news has been the devastating flooding that is going on in parts of Pakistan.  While it is true that the overall annual climate of Pakistan is generally quite dry, summer is the wet season there, as Pakistan is on the northernmost margins of circulation pattern known as the Indian Monsoon.  On today’s episode of Weather Break, we take a look at the situation in Pakistan and see how the monsoon circulation creates these terrible floods.

Links

For the latest news about the flooding in Pakistan, try this Google News Search on the term “Pakistan flooding”.

For more information about what YOU can do to help the people of Pakistan in their time of dire need, visit the websites of Oxfam, the American Red Cross, and Pakistan Relief.

Related Episodes

Flooding in the Sahara

Flooding in Bihar

One of the defining images from this summer’s BP oil spill has to be the shots of vast oil slicks being burned on the surface of the ocean.  Burning turns out to be a fairly efficient way to get rid of oil on the surface of the water, under the right conditions.  Well, meteorologists know that hurricanes are favored when sea surface temperatures are high, and so pictures from the BP oil spill got us wondering whether or not the burning of oil slicks has in any way increased the surface temperature of the Gulf of Mexico.  Observations do show that the waters there ARE unusually warm right now, and the amount of oil burned is huge, releasing vast amounts of heat into the environment.  On today’s episode of Weather Break, Dr. Jon Schrage of the Creighton University Department of Atmospheric Sciences runs the numbers to figure out if burning spilled oil has increased the risk of hurricanes in the Gulf of Mexico.

Links

Here is the spreadsheet I used to do these calculations.

Here are the sources of information we used to get the raw data:

Here we are, nearly half way through the 2010 hurricane season in the Atlantic, and so far the season has been pretty quiet.  You might remember that earlier in the year there were fears that 2010 could turn out to be one of the most active on record.  Well, forecasters with the federal government recently released their updated forecast for the rest of the hurricane season, and while it’s true that they DID cut down the total number of storms expected slightly, they are still calling for a remarkably busy year.  What gives the forecasters so much faith that this is still going to turn out to be a big year for hurricanes and tropical storms?  Tune in to today’s episode of Weather Break to find out!

Links

Here is a story from the Christian Science Monitor about the revised hurricane season forecast.

Get information about the current status of hurricanes and tropical storms in the Gulf from the National Hurricane Center or Unisys Weather.

Related Episodes

Forecasts for the 2010 Atlantic Hurricane Season

Tropical Storm Zeta

On yesterday’s episode of Weather Break, we introduced the so-called “Saharan Air Layer”–an air mass that forms of Africa’s Sahara Desert and, therefore, is extremely hot, dry, and dusty.  At this time of year, tropical meteorologists are particularly concerned about the Saharan Air Layer because it tends to suppress the growth and development of hurricanes if it moves out over the tropical Atlantic Ocean.  As it happens, monitoring and tracking the position of the Saharan Air Layer is possible due to advancements in satellite technology.  Special sensors onboard satellites operated by NASA, NOAA and other federal agencies can be used to infer the location of the Saharan Air Layer, improving the quality of hurricane forecasts, as discussed on today’s episode of Weather Break.

As you might well imagine, air masses that come off of the Sahara Desert in North Africa are extremely hot, extremely dry, and very dusty.  What you probably DIDN’T know, however, is that these air masses are very effective at wiping out the small, disorganized storm systems that CAN develop into hurricanes over the Atlantic.  Meteorologists often think of the so-called “Saharan Air Layer” (or the SAL) as being something like a “hurricane suppressant”, and so at this time of year it becomes very important to track where the SAL is and how it is influencing hurricane seedlings.  The problem is that these storm systems typically happen far out to sea, hundreds or even thousands of miles from the nearest weather station.  Fortunately, advanced techniques are making it possible to track the SAL using satellites, as discussed on today’s episode of Weather Break.

At this time of year, everyone needs to be thinking about protecting themselves from the potentially harmful radiation from the sun.  Ultraviolet radiation can lead to skin cancer and sunburns, but it’s relatively easy to prevent these conditions with a little bit of sunscreen and a little bit of common sense.  On today’s episode of Weather Break, we provide you with some tips to help protect you and your family this summer.

LINKS

For more information about protecting your skin from the potentially dangerous forms of solar radiation, we recommend the Sun Safety Alliance, theAmerican Cancer Society, and the Environmental Protection Agency.

The Weather Channel provides online maps showing where the risks of UV damage is greatest today.

Your local TV meteorology probably tells you the humidity each night on the news in terms of the so-called “relative humidity”, but a much more useful number is the “dewpoint temperature”.  This measure of humidity tells us the temperature to which air would need to be cooled in order for condensation to happen and dew to form.  This is a much more direct measure of the amount of water vapor in the air than the relative humidity is, and so meteorologists tend to think about humidity in terms of the dewpoint.  The highest dewpoint ever measured was in the mid 90s, which was remarkably close to human body temperature, which is, of course, 98.6°F.  Amazing things would start to happen if the dewpoint were ever to reach human body temperature–things that Dr. Jon Schrage discusses on today’s episode of Weather Break.

LINKS:

There are LOTS of resources online that can provide you with explanations of the dewpoint temperature.  Rather than singling just a few of these out, here is http://www.google.com/search?rlz=1C1CHNB_enUS326US327&sourceid=chrome&ie=UTF-8&q=dewpoint.

Yesterday on Weather Break, we started talking about Snowball Earth–the idea that the entire Earth (including the tropics!) has been buried under snow and ice several times over the last few billion years.  The so-called Snowball Earth hypothesis is quite controversial, in part because most of the evidence that these glaciers would have left behind has been destroyed by millions of years of erosion and plate tectonics.  Still, Snowball Earth has been an important idea in science because of its implications for the search of extraterrestrial life, since several of the possible worlds where life might exist are currently locked in ice.

LINKS:

Probably the best and most convenient source of information about the Snowball Earth hypothesis is SnowballEarth.org. However, we certainly think that the following websites are also useful: Harvard University, California Institute of Technology, Nature, New Scientist, Science Daily, and Wikipedia.

Remember the movie “The Empire Strikes Back”?  I think that one of the best planets we ever saw in the “Star Wars” movies was the ice planet of Hoth.  Hoth was the new hideout of the rebels in the movie, and it was a planet completely covered in ice and snow.  Amazingly, Earth has probably been an ice planet like Hoth a couple of times in its history, too.  Climate scientists call this idea “Snowball Earth”.  It’s thought that the entire Earth could have been completely covered by snow and ice because of a feedback between the heat and light of the sun and snow on the surface of the planet.  On today’s episode of Weather Break, we start talking about how it could have come to pass that the entire world–including the tropics–could be buried under ice sheets.

LINKS:

Probably the best and most convenient source of information about the Snowball Earth hypothesis is SnowballEarth.org.  However, we certainly think that the following websites are also useful: Harvard University, California Institute of Technology, Nature, New Scientist, Science Daily, and Wikipedia.

The meteorology community is buzzing about the possible discovery of a “new” type of cloud, tentatively named “Undulatus asperatus”.  When we say that this is a “new” type of cloud, that doesn’t mean that these clouds hadn’t happened in the past–it just means that in that past we were apparently miscategorizing them when they were observed.  So what does an “asperatus” cloud look like, and what does it mean?  Tune in to today’s Weather Break to find out!

LINKS:

Here is some more information about asperatus clouds.

If you take a look at the title for today’s episode of Weather Break, you might think that this is a silly question.  I mean, OBVIOUSLY clouds and storms move, right?  You only have to watch them patiently to see them move across the sky.  However, that’s not exactly what we are talking about today — that’s just the drifting of the clouds with the winds.  Rather, the question that we’re asking is whether or not clouds and storms can move in ways OTHER than just with the wind– can these weather features somehow move UPWIND, for example?  Tune in to today’s episode of Weather Break for all the answers!

Links

We love time lapse movies of clouds.  So do lots of users at YouTube.

All this week on Weather Break, we have been following the growth of a microscopic cloud droplet into a true raindrop.  We’ve seen that, within the cloud, there are both processes that contribute to the GROWTH of the droplet as well as processes that tend to LIMIT the growth of the droplet by continuously breaking the droplet up into smaller pieces.  Now the journey of our raindrop is nearly complete, as the drop is about to exit the bottom of the cloud and make the final trip across the subcloud layer and to the surface of the Earth.  However, this last step of the journey is particularly difficult for the drop, as (by definition) the layer of air beneath the cloud is not saturated, meaning that our little raindrop is going to be evaporating as it falls.  If it doesn’t make it all the way to the ground, meteorologists describe this rainfall as “virga”– a particularly photogenic weather phenomenon that we discuss on today’s episode of Weather Break.

Links

There are vast numbers of pictures of virga online.  Probably the best place to start is this Google Image Search on the term “virga”.

Our friends at the Cloud Appreciation Society have a lovely collection of images of virga, too.

Related Episodes

• How Big are Clouds?
• Why are Clouds Flat on the Bottom?
• Why are Clouds Lumpy on Top?

So far this week on Weather Break, we’ve been following the growth of a single droplet of water in a cloud, trying to understand the processes at work that lead to the droplet’s growth to the size of a raindrop that is big enough to fall out of the bottom of the cloud and make it all the way to the ground without evaporating.  Yesterday we learned about the processes of collision and coalescence, and how these processes lead to the runaway growth of the droplet — which was necessary, since the cloud droplet needed to get about a million times bigger before it would be large enough to be considered a raindrop.  However, you know from your own experience that there is a limit to just how big a raindrop can be — you’ve never seen a raindrop the size of a bucket of water, for example, right?  Clearly, therefore, there must be processes at work in the cloud that also LIMIT the size of a raindrop, keeping it from growing to dimensions that we know aren’t realistic.  On today’s episode of Weather Break, we talk about the process of “fragmentation” and how this process breaks up raindrops as they fall.

Links

For more information about the fragmentation of raindrops, visit:

• Nature
• Earth Magazine
• Imperial.ak.uk
• Journal of the Atmospheric Sciences

Related Episodes

• The World’s Biggest Snowflake

This week on Weather Break, we’re talking about the ways in which microscopic specks of liquid water in a cloud grow to form raindrops.  To do this, we’ve been following the journey of a single raindrop, from its formation to the moment that it hits the ground.  Part of the trick to the formation of raindrops involves the fact that almost all rain — even in the middle of the summer — is actually in the form of ICE at some point during its life.  In a cloud, it turns out that ice crystals are much easier to grow than liquid water droplets are, so it is much more efficient for the cloud to produce ice that will eventually melt — even if that means that some of the liquid water droplets in the cloud need to evaporate in order to “feed” the ice crystals.  ”Ice crystals grow at the expense of water droplets” is a mantra in the world of cloud physics and meteorology, and you’ll see what that means for our little raindrop on today’s episode of Weather Break.

Links

For more information about the growth of ice crystals in a raincloud, visit:

• Geography for Kids
• College of DuPage
• Wikipedia

Related Episodes

• Freezing Drizzle
• Snowmaking

This week, as a thought experiment we are going to follow the journey of a single raindrop through a cloud– from its formation as a microscopic speck of water to when it hits the ground with a splat.  Today we start with the conversion of water vapor in the cloud into that first tiny water droplet.  How does this happen, and can this process actually lead to the formation of raindrops big enough to fall to the ground in the form of rain?  Find out on today’s episode of Weather Break!

Links

For more information about how raindrops form, visit:

• InfoPlease
• Physical Review Focus
• Science Daily
• New Scientist

Related Episodes

• Alfred Wegener
• Superterminal Raindrops
• Drizzle

The phrase “a lonesome place against the sky” comes originally from the poem “Lincoln, the Man of the People” by Edwin Markham, and it’s often used to describe the loss that a group feels after a senior member of the group dies.  The expression actually refers to the unfamiliar patch of sky you see when an old tree falls in a storm– something very relevant to folks in Omaha right now, as a strong line of thunderstorms last week brought winds in excess of 80 MPH.  All around the city, broken old trees have been cut apart in recent days, and power has been completely restored.  What kinds of thunderstorms and weather conditions does it take to produce such hurricane-force winds at the surface of the Earth, tearing down trees and opening up “lonesome places against the sky”?  Tune in to today’s episode of Weather Break to find out!

Links

Follow this link for the complete text of the poem “Lincoln, the Man of the People” by Edwin Markham.

Related Episodes

• Haboobs
• The Gust Front and Outflow
• Assessing Tornado Damage

Textbooks describe most of the key gases in the atmosphere — stuff like nitrogen and oxygen — as being “colorless and odorless”.  Even methane or natural gas is “colorless and odorless”– that smell from natural gas is actually an additive that is put in specifically to give natural gas a strong scent that helps you realize when you have a gas leak.  In thinking about the term “colorless”, here at Weather Break we started wondering if there were any gases that we NOT “colorless” — we certainly couldn’t come up with any at first, but after doing a little reading we came to understand that there ARE quite a few colored gases.  The key is that all of the colored gases are toxic and occur in extremely small quantities in the atmosphere.  On today’s episode of Weather Break, we take a look at some of these interesting — but corrosive — colored gases.

Links

Here are some online resources about some of the colored gases discussed on today’s program:

• NO2:  The Environmental Protection Agency, Wikipedia
• Cl2:  Lenntech, Wikipedia
• Br2:  The Centers for Disease Control and Prevention, Wikipedia
• I2:  Chemical Book, Wikipedia

Related Episodes

• Krypton
• Residence Times in the Atmosphere
• Alessandro Volta and the Discovery of Methane
• Methane and Global Warming
• Methane

Yesterday on Weather Break, we started talking about dust devils.  Dust devils are something like “mini tornadoes”– although they are in no way associated with severe weather, they actually DO form by mechanisms that are quite similar to how the more powerful tornadoes work.  Yesterday’s program talked about ways in which dust devils and tornadoes were similar yet differed in their formation and their structure.  But there is one more important difference– while almost all tornadoes rotate counterclockwise, only half of dust devils do, with the remainder demonstrating clockwise rotation.  Clearly, this difference is important, and it sheds light on key differences in the kinds of weather regimes in which these two types of atmospheric vortices form, as we’ll see on today’s episode of Weather Break.

Links

For more information about dust devils, we recommend the National Weather Service office in Flagstaff, AZ, the Eldorado Valley Dust Devil Project,  this gallery, or Wikipedia.

Check out these videos on YouTube, showing lots of dust devils.

Related Episodes

• Australian Dust Storms
• The Saharan Air Layer
• Monitoring the Saharan Air Layer
• Haboobs

When the sun is out, its rays strongly heat the ground, and that heat from the ground quickly transfers into the air just above the surface.  Under the right conditions, this produces strong rising plumes of air called “thermals”, and these thermals can give rise to dust devils.  Dust devils are something like “mini tornadoes”– although they are in no way associated with severe weather, they actually DO form by mechanisms that are quite similar to how the more powerful tornadoes work.  On today’s episode of Weather Break, we take a look at some of the ways dust devils and tornadoes are ALIKE, and some of the ways in which they are DIFFERENT.

Links

For more information about dust devils, we recommend the National Weather Service office in Flagstaff, AZ, the Eldorado Valley Dust Devil Project,  this gallery, or Wikipedia.

Check out these videos on YouTube, showing lots of dust devils.

Related Episodes

• Australian Dust Storms
• The Saharan Air Layer
• Monitoring the Saharan Air Layer
• Haboobs

At this time of year, you’ll often hear people talk about how they could “see the heat rising” off of a driveway or a parking lot.  You know what they are saying– they’re describing that wavy, shimmering appearance to the light.  Surprisingly, that phenomenon is seen just as often — maybe MORE so — in the winter!  And, for that matter, what you are seeing when you “see the heat rising” is not heat at all — it’s rising plumes of hot air.  On today’s episode of Weather Break, Dr. Jon Schrage explains what you are seeing when you “see the heat” and how this relates to other optical phenomena in the atmosphere.

Links

For reliable forecasts for various parts of the country, we recommend weather.gov and Unisys Weather.

Related Episodes

• The Recent Heat Wave in the East
• Heat Lightning
• The Little Ice Age

Lots of songs contain images of activities in the rain, from Gene Kelly’s “Singing in the Rain” to Willie Nelson’s “Blue Eyes Crying in the Rain”.  But truth be told, it’s not much fun to be “in the rain”–it’s cold.  Why is rain so cold, and should you run or walk in the rain if you want to stay as dry as possible?  We tackle all these questions and more on today’s (750th!) episode of Weather Break.

Links

As mentioned in the episodes, Mythbusters has tested the idea that walking in the rain keeps you drier than running.  Here the Annotated Mythbusters confirm the work. But that doesn’t really settle the issue.  Here are lots of other websites where folks are debating the merits of running vs. walking in the rain:  1 2 3…

Related Episodes

• “I Love a Rainy Night”
• “An Ode to Pluviculture”
• “The Summer Wind”
• “Over the River and Through the Woods”

Yesterday on Weather Break, we spoke with Mary Jean Johnston, the project administrator for the Punxsutawney Weather Discovery Center, which is the home of the Meteorologist Hall of Fame.  It turns out that the Weather Center is a particularly nice educational center for people who are interested in the weather and climate– especially kids, who enjoy the hands-on activities.  On today’s episode of Weather Break, we learn more about the work and the mission of the Punxsutawney Weather Discovery Center.

Links

Here is the homepage of the Meteorologist Hall of Fame, which is at the Weather Discovery Center in Punxsutawney, Pennsylvania.

Where in the world is Punxsutawney?

Related Episodes

• Candlemas
• National Weatherman’s Day 2009
• National Weatherman’s Day 2007
• Or see any of our past episodes about famous meteorologists!

A lot of the episodes that we have produced for Weather Break have been about famous meteorologists and atmospheric scientists.  We often use the anniversaries of their births or deaths to talk about the contributions that these men and women have made to this discipline and our understanding of the atmosphere.  From time to time, we’ve even joked that they should be in some kind of “Meteorologist Hall of Fame”.  However, here at Weather Break we only recently learned that there IS, in fact, such a thing–it’s at the Punxsutawney Weather Discovery Center in Punxsutawney, PA.  We contacted Mary Jean Johnston, the project administrator for the Weather Center, to learn more about who is on the Meteorologist Hall of Fame and who decides which weather professionals get inducted into the Hall each year.

Links

Here is the homepage of the Meteorologist Hall of Fame, which is at the Weather Discovery Center in Punxsutawney, Pennsylvania.

Where in the world is Punxsutawney?

Related Episodes

• Candlemas
• National Weatherman’s Day 2009
• National Weatherman’s Day 2007
• Or see any of our past episodes about famous meteorologists!

Many of the weather patterns that you and I are familiar with in this part of the country are causes by waves in the jet stream.  These waves, like all waves (e.g., sound waves or waves in the ocean) propagate, or move, creating the changes in the weather that we normally experience.  But from time to time the weather patterns become “blocked”–the waves in the jet stream fail to propagate.  How does this happen, and what does it mean for weather at the surface of the Earth?  These questions and more are answered in today’s episode of Weather Break!

Links

The current position of the jet stream across North America can be determined from this map, for example.

For reliable forecasts, we recommend Unisys Weather or the National Weather Service.

For somewhat technical information about the propagation of waves in the jet stream, see this powerpoint, this file, or these resources.

Related Episodes

• Troughs and Ridges
• The Fastest Winds
• The Midlatitude jet Stream
• Carl-Gustav Rossby

Recent news has been largely dominated by the incredible heat wave in the East.  In that highly-populated part of the country, the power demands of increased use of air conditioning have tested the limits of the electrical grid.  On today’s episode of Weather Break, Dr. Jon Schrage takes a look at the particular set of circumstances at work in the atmosphere to create this particular heat wave.

Links

For the latest news on the heat wave, try this Google News Search on the term “heat wave”.

For reliable forecasts, we recommend Unisys Weather or the National Weather Service.

Related Episodes

• Heat Waves
• The Dog Days of Summer
• 91°F in Pierre in April!