Question Your World - How often does it thunder??

Thunder!! by ScienceMuseumofVA

How often does thunder happen on Earth?

A LOT!! 2,000 times per minute!! Also impressive is the amount of lightning that strikes the Earth every minute. 6,000 lightning strikes per minute! These bright flashes and loud rumbles of thunder are scary to some, but rain fall is a vital part of what makes Earth such a wonderful place for us to live on.

Here's an idea. Instead of being startled by the next thunder rumble you hear, you can use it to do a mini weather forecast.
Once you see lightning, just count the amount of seconds before you hear thunder. Then divide that number by 5.

Example:
(seconds between the lightning flash and hearing thunder) 10/ 5 = 2
The storm is 2 miles away from you!
That's enough time to grab an umbrella!

Thunder is pretty impressive stuff.

Neptune

A lot has been discovered about Neptune since its initial sighting in 1846. The Voyager 2 spacecraft, on Aug 25, 1989, did a fly by of this blue celestial giant and sent back some photos and other data that has helped the science community understand more about the last planet on the block. Here are some interesting factoids about Neptune:
8th Planet from the sun
Gaseous Giant
13 Moons
Named after the Roman god of the oceans, Neptune
Has rings…just like all the other gaseous giants
2.68 BILLION miles from Earth at its closest point in orbit
60,190 Earth days (164.8 Earth years) for Neptune to orbit the sun once!!
Looks cool…because it is VERY cool…as in cold -330F (72 Kelvin)…(-201 C for the non-US friends of the Science Museum of Virginia)…brrr!
After 2006's demotion of Pluto, this blue gaseous giant became the last official planet in our solar system.

What one degree will do...

If you lowered the thermostat on your water heater by one degree this year, you could save enough energy to microwave 207 bags of popcorn or power a fish tank for 19 days.

If 1000 people joined you, we could power 10 homes for 30 days or power a hospital for 4 days.

More energy facts at the Energy Generator:
http://www.willyoujoinus.com/usingenergywisely/energygenerator/?gclid=CKOi6rTRjagCFcPd4AodWDCxDQ

Question of the Week

In the wake of the devastating earthquake in Japan, tsunamis are on people's minds.  How much do you know about them? 

Take this brief tsunami quiz and find out:

1.  Name 4 geologic events that might cause a tsunami.

2.  Tsunamis are also called wave trains because they are a series of waves, not just one wave.  How far apart in time can they be?

3.  In deep ocean water, how fast can a tsunami travel?

4.  Suppose you are in a boat in the middle of the ocean and a tsunami approaches.  What would happen?

5.  What happens when the tsunami approaches land?

6.  Has Virginia ever experienced a devastating tsunami?

Answers:
1.  Tsunamis may be caused by earthquakes, landslides, volcanic eruptions or a meteor impact in the ocean.
2.  Tsunami waves can be as far as one hour apart.
3.  In deep ocean water, tsunamis can travel as fast as 500 miles per hour (800 kilometers per hour), as fast as a commercial jet.
4.  Not much.  In the open ocean, tsunamis are often less than a foot tall.  You probably wouldn't notice its passage.
5.  As a tsunami approaches land, the depth of the water decreases causing the bottom of the wave to slow while the top continues at the same speed.  The sea then begins to rise, either as a giant wave or as a rapidly rising tide.
6.  Yes, a meteor struck at the current mouth of the Chesapeake Bay about 35 million years ago, causing a huge tsunami which may have flowed over the Blue Ridge Mountains.

The SR-71: Designed with a Slide Ruler!

So you've probably seen the big black plane outside of the Virginia Aviation Museum when you're on your way to the airport. But what exactly is it?


This plane is the SR-71 Blackbird and was manufactured by Lockheed under the direction of the CIA. After World War II, the United States wanted to maintain a close watch on Soviet missile and nuclear weapon production. To do this a plane was needed that could fly very high and very fast to both escape incoming missiles and to avoid detection by Soviet radar, all while taking photographs of what was going on below.

Flying at altitudes above 80,000 feet meant that the aircraft would be very hot but in very cold temperatures. Because of this virtually everything on the aircraft had to be specifically designed for the SR-71: even the washers! In addition, keep in mind that this is 1960s technology- the engineers of the SR-71 used a slide ruler to design this aircraft, there were no computers.
So what exactly can this plane do?


The SR-71:

• Can fly at a top speed of Mach 3.3 or 2,200 miles in one hour
• Can climb to an altitude of 85,000 feet where the curvature of the earth is visible
• Is constructed of 93% titanium
• Has a special coating of black paint that radiates heat away from the aircraft and into the cold high-altitude air
• Reaches a temperature of 600 degrees Fahrenheit at cruising speeds with a max temperature of 1200 degrees Fahrenheit at the engine
• Grows in length about three to four inches and widens one to two inches during flight as a result of the intense heat it generates
• Carries 80,000 pounds of fuel
• Can stay in flight for two and a half to four and a half hours with at least one in-flight refuel
• Can fly from New York to London in 1 hour and 55 minutes
• Can fly from Los Angeles to Washington, DC in 64 minutes

Only 32 of these aircraft were made and only 20 survive (though none were shot down by enemy fire- the SR-71 was able to 'outrun' any missile sent its way). VAM's SR-71 is on loan from the National Museum of the US Air Force. The SR-71 still holds the Air Speed Record by a manned airbreathing jet since 1976. This makes it the fastest known aircraft in existence- but makes me wonder just how fast the current classified US jets can go...

Question of the Week

Today in Richmond, we are experiencing a messy and somewhat hazardous mix of snow, sleet and freezing rain. 

Do you know what atmospheric conditions cause each kind of frozen precipitation?



Answer:  Winter precipitation types generally depend on the vertical temperature profile of the atmosphere.

• Snow falls when the temperature of the entire depth of the atmosphere from the cloud to the ground is below freezing (32 F or 0 C).
• Sleet falls when there is a fairly shallow layer of warmer air (above freezing) between the cloud and the ground but the temperature at the ground is below freezing.  Snow falls from the cloud, then partially melts in the warmer layer and then refreezes in the colder layer near the surface, forming pellets of ice.
• Freezing rain falls when there is a deep layer of warmer air (above freezing) but the temperature is below freezing at the ground.  Snow falls from the cloud, melts completely in the warm layer and then refreezes either just before hitting the ground or on contact with the cold surface.

Is It Winter Yet? Maybe, Maybe Not…

Snow frozen onto a tree in Germany.
Photo courtesy of Wikipedia

Tuesday, December 21, is the Winter Solstice and usually considered the first day of winter. However, meteorological winter is already here! So what’s the deal? Well, the definition of winter depends on whom you ask.

A meteorologist defines winter as the three coldest months of the year: December, January and February. An astronomer defines winter as the three months between the Winter Solstice (December 21 or 22) and the Spring or Vernal Equinox (March 20 or 21). What’s the difference?

The definition of meteorological winter is fairly straightforward. Climatologically-speaking, the three coldest months of the year are December, January and February in the Northern Hemisphere. Therefore, meteorological winter begins on December 1 and ends on February 28 (or 29). In the Southern Hemisphere, the seasons are reversed, meaning if you lived in Rio or Buenos Aires, summer would begin in December and winter would begin in June.

Astronomical winter begins on the Winter Solstice, the shortest day of the year. The Earth has seasons and variable daylight hours because its axis is tilted 23.5° relative to its orbit around the sun. Winter in the Northern Hemisphere occurs when the northern half of the planet is tilted away from the sun. This tilt causes sun’s energy to be weaker on the Earth’s surface because:

• The sun shines on the Earth’s surface at an oblique angle.
• The sun’s energy is spread out over a larger area, diluting its strength. 
• The sun’s rays travel through more atmosphere before they reach the surface. 
• Days are shorter so there is less time for the sun to heat the surface. 

Less energy from the sun on the Earth’s surface means colder temperatures in the atmosphere – so winter arrives. For more information, check out last year’s blog about the Winter Solstice: http://sciencemuseumofvirginia.blogspot.com/2009/12/winter-solstice.html

Here are some questions for you to ponder:

• If the Earth’s axis had no tilt, would we have seasons? 
• If the tilt was at a greater angle, what would our seasons be like? 
• Do you think other planets in the solar system have seasons too? 
• How did Earth’s axis get tilted in the first place?

Question of the Week

It's snowing!  Snow showers are also predicted for Thursday and a winter storm might hit us this weekend.  Remember last December? 

Now for the Question of the Week:
What is the percent chance of a white Christmas in Richmond (in any given year)?

Answer:  In Richmond, there is a less than 10% chance that measurable snow will fall on Christmas Day.  There's about a 13% chance that at least a trace of snow will be on the ground and about a 7% chance that at least 1" will be on the ground.

Several inches of snow are predicted for today (Thursday, December 16), and a coastal storm this weekend has a 50-50 chance of bringing us more snow.  Will we see snow on the ground for Christmas?  We might...

Question of the Week

The SunTrust Richmond Marathon is this Saturday, November 13, 2010.  NBC12's Andrew Freiden has posted the following weather forecast for race day:

•  7 am - low to mid-40's, mostly sunny
•  Noon - near 60, partly sunny
•  3 pm - mid-60's, partly sunny

What is ideal race weather?



Answer:  Ideal running weather -

• Temperature - runners have different preferences but generally prefer low 40's to mid-50's. Intense muscle activity generates a lot of heat; cooler temperatures help prevent overheating.
• Humidity - low to moderate. Lower humidities mean less water vapor and more oxygen with each breath. The runner's body does not have to work as hard to get enough oxygen to his/her muscles.
• Wind - 5 mph. A slight breeze is better than no wind at all. The breeze helps keep the runner cool by evaporating sweat from the runner's skin. As for direction, a tail wind is always welcome.
• Time of day - morning. Morning means less glare off cars and pavement and less wind, also less traffic.

Finally, the rains came

Last week, the Richmond area received about five inches of rain, which helped to reduce the rainfall deficit in our area for the year. For the record, though, we’re still short by 4.9 inches of rainfall for the year.

During the weekend before remnants of Tropical Storm Nicole drenched the Richmond area, the county of Chesterfield had announced implementing mandatory water restrictions on September 28, 2010. For several weeks prior to the announcement of mandatory water restrictions, I witnessed homeowners with automatic sprinkling systems and golf courses in our area persistently irrigating their brown lawns as the water level in Lake Chesdin continually inched downwards to record low levels. Why do they do this?

To me, such behavior is not unlike that described in a 1968 journal article entitled “The Tragedy of the Commons” in the journal Science, December 13, 1968 by the late, renowned ecologist, Garrett Hardin. Using the concept of tragedy of the commons, we may view water as a common resource, which we pay very little for. Each of us wants to maximize the beauty of our lawns, our profits from golfers, etc. Each of us reasons that if I water a little extra to keep my lawn green, it won’t matter. We do this for our own self interest, without regard for the resource and end up doing harm to the common water supply and the rest of the water user groups as well. If all water users make this individual economic decision, then the water resource in common will be exhausted to the detriment to all.
So, in my infinite quest to do the ethically right thing and not harm others with my own actions, I used my truck to transport water in four 5-gallon plastic buckets from the James River to our home about two miles away to water our winter vegetable garden of Bloomsdale spinach, dwarf Siberian curly leaf kale, cilantro, and mustard greens. Fortunately for me, it started raining…I didn’t like adding additional CO2 into the atmosphere, and taking time away from family as I drove to and from the river.

As an aside, the availability of clean drinking water is at a crisis. About a year ago, the federal government predicted that within five years at least 36 states will experience water shortages as a result of climate change (rising temperatures and drought), population growth, urban sprawl and waste. Barry Nelson, senior policy analyst for the Natural Resources Defense Council (NRDC), summed up the change in philosophy that is upon us: “The last century was the century of water engineering. This century is going to have to be the century of water efficiency.”

Remember Hurricane Andrew?

As Hurricane Danielle churns far out in the Atlantic, I am reminded of another hurricane that made landfall on this day…

On August 24, 1992, a small but extremely intense Hurricane Andrew slammed into South Florida. Andrew made landfall as a Category 5 hurricane, the 3rd most intense landfalling US hurricane and the 1st in total estimated US property damage at the time. (Katrina eclipsed it in both intensity and damage in 2005.) Andrew hit the highly populated Miami area after a 27-year lull in hurricane activity in the Atlantic basin. During the period between 1965 and 1992, only 2 hurricanes of any significance made landfall in Florida, both in the panhandle. At the same time, the coast around Miami had experienced unprecedented development, populated largely by residents from the Northeast who had no experience with Florida’s history of violent hurricanes. As a result, South Florida was devastated. Damage was extensive, estimated at about $30 billion. Fifteen people lost their lives directly due to the hurricane and another 25 by more indirect means.

Yes, hurricanes can be devastating and deadly; however, I have always been fascinated by them. (I confess - I am a weather nut.) Don’t get me wrong – I do not want them to come ashore and destroy homes and lives; however, watching them develop from a messy disorganized cluster of clouds into a perfect spiral inspires me to wonder at the beauty and power of nature. But I do prefer that all this beauty and power stay well off-shore…

East Coasters Roasted by Heat Wave

By Ben Remo

Science Museum of Virginia intern

Residents of the east coast may have noticed an increase in heat lately. This increase has led to scorching temperatures of over 100 degrees. Most might be asking, how can this possibly happen? Why should we be subjected to such a hot summer? These dangerous, record breaking temperatures are caused by a heat wave currently hovering along the Atlantic coast. Last week, the northeast region experienced the worst heat wave in years.
At times temperatures have been above 100 degrees in some areas. New York City has opened over 100 cooling centers around the city providing relief from the heat for those who do not have access to air conditioning. Here in Central Virginia we have been subjected to temperatures around 100 degrees for days at a time.

How Heat Waves Work
Heat waves occur when temperatures are 10 degrees or above the normal averages in a region for a substantial period of time.
Ironically, heat waves do not mean that the earth is closer to the sun, a common misconception. According to National Geographic News, the week after 4th of July weekend, the earth was farther away from the sun than it will be at any other time this year. This is because the distance between us and the nearest star has little to do with the surface temperature here on earth.
The tilt of the earth on its axis has more to do with the occurrence of a heat wave. This is what makes for seasonal change. It is currently summer in the Northern Hemisphere because we are pointed towards the sun on the axis.
The formation of heat waves can be attributed to ridges of high pressure in the atmosphere that hang around the sky for some period of time. These ridges make the air hot and move clouds away, making the surface hotter. Clouds are a lot like oven mitts for the earth’s surface. The clouds act as a buffer between the surface and the sun just like oven mitts are a buffer between our hands and a hot object in the kitchen. When those “oven mitts” are not around, it makes for some hot days.

How to Stay Cool
OK. We know what causes heat waves; the next step is learning how to stay cool in the middle of one.
First, dress appropriately for the heat. With work that may be easier said than done. But on the weekends or after work, try to wear open toed shoes (no socks!) and loose, breathable clothes. When running the air conditioner, turn on all the fans in the house. It helps the cool air spread throughout the house. Next, go to the local pool or water park. While keeping you cool, a day at the pool is also good family fun. Drink cold water to stay hydrated. If you’re hydrated, you’re cool. Lastly, according to http://www.greenlivingonline.com/ ingredients in spicy foods actually cool you down after awhile. Add a marginal amount of peppers to any meal to cool you down on a hot day.

Global Warming?
Can a heat wave be attributed to global warming? That’s a sticky question. Global warming is climate; a heat wave is weather. The basic difference is time. Climate is long-term averages of weather, while weather is what’s outside right now. Some scientists believe global warming will change prevailing weather patterns to cause events such as heat waves, stronger hurricanes and even an extra snowy winter like the one just past. So the answer is maybe and maybe not. Scientists are studying both climate and weather trying to find answers. In the meantime, stay cool!

Tis the Season… for Nor’easters?

What will this winter be like? If the current weather pattern continues, the East Coast will certainly be stormy. Friday night through Saturday (December 18-19), Virginia experienced yet another intense Nor’easter (see blog of November 12). This one dumped huge amounts of snow over the central and western parts of the state.
Whether Virginia gets rain or snow from a winter Nor’easter depends largely on the track of the storm. A more westerly inland track will pull in warmer ocean air and Virginia will usually get rain. If the center of the storm stays just off the coast, cold air is often pulled in behind the storm and Virginia can get snow, sometimes lots of it. Nor’easters can intensify to hurricane strength and bring extremely high winds, coastal flooding, beach erosion, and heavy rain or snow to the mid-Atlantic and Northeast states. In the satellite picture above, note the hurricane-like eye in the center of this intense storm.
In addition to the heavy snow and gusty winds, this storm also included thundersnow. Thundersnow occurs only rarely and is basically a winter thunderstorm with falling snow instead of the usual rain. The lightning is nearly blinding due to its reflection off the white snowflakes, and the sound of the thunder is acoustically suppressed by the snowfall. Normally, thunder can be heard many kilometers away from a thunderstorm, but the thunder from thundersnow can only be heard 2 or 3 kilometers away. We had thundersnow at my house just after midnight on the 19th with at least two very bright lightning strikes and accompanying thunder.
How much snow did you get from this storm? I had 1 foot at my house in Midlothian, about 15 miles west of Richmond.

What do you think of this storm? Virginia and much of the mid-Atlantic coast is experiencing a Nor'easter today: heavy rain, gale force winds, coastal flooding, downed trees, power outages, beach erosion... well, you catch my drift. The storm gets the name Nor'easter because the wind blows primarily from the northeast. A Nor'easter is a cyclone, or low pressure system, whose center stays just off the coast. Nor'easters can have winds of hurricane force and can sometimes intensify very quickly.

This particular storm began as hurricane Ida, a tropical cyclone. Tropical cyclones form over very warm ocean waters and get their energy from the release of latent heat when water vapor condenses into water droplets. They have a warm core, no fronts associated with them and have their strongest winds near the surface. Extra-tropical cyclones get their energy from temperature gradients, such as when a warm air mass collides with a cold air mass. They have a cold core, usually both warm and cold fronts associated with them and have their strongest winds in the upper atmosphere. Tropical cyclones can "morph" into extra-tropical cyclones and vice versa, although the latter is more rare.

Many of the worst blizzards in the Northeast US were Nor’easters. Extreme cold often follows in the wake of a Nor’easter, due to cold air being dragged out of Canada by strong northwest winds behind the storm.

The book and movie The Perfect Storm was about an actual 1991 Nor’easter that absorbed Hurricane Grace and later moved far enough south to become a hurricane itself. Unlike most hurricanes, this storm was never named, and New Englanders still refer to it as the No-Name storm.

Did you know surfers love Nor'easters? Waves can be very high during these storms. Even though it is cold, they just don their wet suits and head out.

Do you have a Nor'easter experience? Here's one of mine: my brother had rented a house in the Outer Banks one spring when a Nor'easter hit. Large quantities of sand blew onto and covered the road near Rodanthe. The highway department managed to open a one-lane track for cars to pass, necessitating a wait for oncoming traffic to clear. In the 30 minutes we were waiting, huge hunks of wet sand were raining down on our car. By the time we arrived at the house, the entire left side of the car was caked in sand. That night the house rocked us like we were in a cradle. It was an experience I will never forget.