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?

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.”

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.

Notes from Northern VA: Deborah and Terry reporting

A picture (or 5) really is worth a thousand words. Wish everyone could have seen the look on our faces when Dr. Maurakis (Gene) told us about the cautionary tales of those "brain eating amoeba" - Naegleria fowleri - that inhabit low level waters at temps of approx 78 degrees. Nice thoughts for our outing tomorrow and our introduction to electrofishing in Prince William Forest Park. Those pictures will certainly tell a story.

Today though we arrived (settled into our swanky new digs) and began to answer some of the aforementioned questions as to why we are here:

“I’m going to Woodbridge because I want to hang out with other teachers…” The best way to get to know each other was finding out what we already do by way of environmental studies and green practices personally & professionally. Steve takes the "less is best" approach by living in a one room studio where he has no trouble remembering to turn off the lights when he leaves a room & where he can't water a lawn b/c he doesn't have one.

“…and experience the natural world in a new way…” Today this meant viewing a turtle or catfish in a tank in one of our participant's labs (the rest of us can only dream of such a tank and lab in our schools) or eating lunch in the setting of a concrete courtyard? Where's the nature? Oh, we must be it. “I’ll spend a lot of time stuck in traffic…” Not today actually - everyone seemed to stay home b/c of the heat “and thinking about how I could use this mark and recapture lesson…” Can they eat the population? Only if they're the Goldfish that come in a cardboard carton….

“Dr. M’s study will establish a baseline for climate change…” that might include how to warm up a classroom designed for 30-40 students w/ only 12 people in it? “and I’ll get help from Summer to develop a proposal for my own study…” like a grant for a lab like Bryan's in the CENS (Center for Environmental and Natural Sciences!) “I’ll learn about so many things: fish and invertebrates and stream characteristics and maps and human impacts and”….and the brain eating amoeba.

“The best thing about this project will be (stuff) I’ll take home…” such as a planimeter for measuring distances of streams on a map…”and meeting new people, and free meals…" off to a great start w/ an excellent dinner out at Macaroni Grill & conversation ranging from experiences w/ students in environmental sciences - to the human impact of folks like Octomom and the Duggars - to the finer points of living w/ grizzlies and navigating NOVA traffic. “I’ll get resources…” such as a laminated/field tested Insect & Crustacean ID Card… “and I’ll do things I’ve never done before!” Like put ink dots on both sides of very small navy and pinto beans.

Above all else today we met Summer Schultz & Dr. Gene Maurakis, two scientists who truly are dedicated to their altruistic cause of providing information about the effects of climate change on our inland waterways. To make the cause even more worthwhile, they are willing to engage us as teachers in providing the tools for a whole new generation to keep up their work. Do they know what they're in for? They say teachers make the most challenging students. Do we know what we're in for? My guess is not a clue, judging by the first class treatment we have received. Could it be they are making these first impressions so positive so as to ward off any further misgivings we might have about standing about in water w/ electroshock sticks while avoiding droplets of amoeba contaminated water as we flee flailing from the stream? Stay tuned to see what answers tomorrow brings.

Deborah Andersen & Terry Milton

A picture is worth a thousand words

SMV is conducting a multi-year study of fishes and invertebrates. Yes, we’re collecting, identifying, and counting critters! But we’re also looking at the physical environment: water temperature, current, pH... all sorts of other factors that determine what critters live where.

OK, this is where I need to get a bit “wordy” to explain things. You see, one goal of this study is designing a mathematical model… basically, a computer program… that can predict what critters should be in a creek. Plug in your values for stream order, stream depth, etc etc… and wow, here’s a list of the fishes and inverts you’ll find!

Believe it or not, scientists get really excited about this type of modeling. A program like this could then predict how climate and ecosystem changes will play out in the future. In the midst of an epic drought? Tweak the input values for water temp and stream depth, and see what happens to your fish populations.

Of course, to build a realistic program, we need to look at data from more than one stream (we’re studying 21.) And we definitely need to consider how human factors (Storm runoff! Culverts! and dams! Oh my!) come into play. Which leads me, in my long-winded wordy way, to today’s pictures, courtesy of Google Earth.

Satellite view #1: half of our study sites are in this region





Satellite view # 2: and the other half are here!

Think we can get some good “human impact” data for our computer program?