December 10, 2013
Marty shared this photo and also some information about the CR510 Pennsylvania Truss Bridge in Marquette County from historicbridges.org:
This is one of the largest, most beautiful, and most significant truss spans in Michigan. Not only does this truss bridge display the Pennsylvania truss configuration, it appears that it may have actually come from the state of Pennsylvania. In 1919, the Michigan State Highway Department purchased the bridge which originally crossed the Allegheny River. Relocating and reusing truss bridges was not unusual in this period of history. An example notice indicating bridges for sale from 1921 is shown to the right. At this time, CR-510 was a state trunk line route and purchasing and relocating this bridge would have been an inexpensive alternative to building a new bridge from scratch. It was erected on the CR-510 location in 1921. The Michigan State Highway Department’s Biennial Report stated that the bridge was one of two toll bridges crossing the Allegheny River within 500 feet of each other and was being removed due to the redundancy. Unfortunately, the report did not state exactly where on the river this bridge came from. Since most of the Allegheny River is in Pennsylvania, it is assumed the bridge came from Pennsylvania, although the Allegheny River does dip into New York State for a short time. Depending on where on the Allegheny River it was originally located, it may have been part of a multi-span bridge.
Pennsylvania truss bridges are an uncommon truss type, and the nature of their design means that they are reserved for longer truss spans. However, even among pin-connected highway Pennsylvania truss spans, this bridge’s span still stands out as fairly long. It is the longest pin-connected highway truss span in Michigan. The truss type is extremely rare in Michigan, and so the bridge has additional significance in the context of Michigan. The bridge also retains excellent historic integrity with minimal alterations despite its long service and being located in two different states over its service life. The bridge has decorative details on its portal bracing, another feature that is rare among Michigan truss bridges.
Read on for more.
More bridges on Michigan in Pictures.
December 7, 2013
Waaaay back when I started out on the capital “I” Internet with an online publication called the Northern Michigan Journal. For over five years I edited NMJ, producing around 4 issues a year that featured some interesting work from a wide range of writers & artists.
Two of these were my friends Jerry Dennis and Glenn Wolff, a writer/artist duo who collaborated on several books. Their first was called It’s Raining Frogs & Fishes: Four Seasons of Natural Phenomena and Oddities of the Sky, a fascinating romp through the oddities and beauties of the natural world through Jerry’s captivating prose and Glenn’s engaging drawings. You can click that link to learn more about the book from Jerry’s website. Trust me, it’s the perfect gift for the nature lover or scientist in your life!
There is more to the birth of a snowflake than Aristotle’s assertion that “when a cloud freezes there is snow.” Snow is not merely frozen rain. Rain occasionally freezes, falling to the ground as sleet or freezing rain, but snow originates independent of atmospheric drops of water. Individual ice crystals for high in the atmosphere when water vapor freezes around dust or other particulates. Without particles to serve as condensation nuclei, water vapor can be cooled to -40 degrees Fahrenheit before freezing occurs. A supercooled cloud of this sort seeded with a few particles often escalates into a snowstorm. The individual crystals collect additional molecules of water vapor one at a time, building on one another symmetrically in a rapidly growing, widening circle. Temperature, wind, humidity, and even barometric pressure will determine the growth and ultimate form of the crystal. Large and elaborate crystals for at higher temperatures and humidity while, while the small, basic crystals such as those common in polar regions form when temperature and humidity are very low. As the crystals fall they bump against each other, breaking off pieces of ice that in turn serve as nuclei for new crystals. As they pass through warmer layers of air they adhere to one another, congregating into snowflakes that may contain a thousand or more crystals.
Snowflakes, then, are aggregates of snow crystals. When the temperature is near or slightly above freezing, snowflakes become wet, adhere to other flakes, and grow to two or three inches in diameter. On very rare occasions, they can grow larger yet. According to a report in a 1915 issue of Monthly Weather Review, a snowfall on January 28, 1887 dropped flakes “larger than milk pans,” measuring fifteen inches in diameter by eight inches thick across several square miles near Fort Keogh, Montana.
Only when the temperature remains consistently below freezing will complete, individual crystals fall to the ground. If the temperature of the cloud they form in and the air they descend through is warmer than 27 degrees Fahrenheit, the crystals tend to be flat and hexagonal. Between 27 and 23 degrees, they tend to be needle-shaped. Between 23 and 18 they are likely to be hollow and columnar, with prismatic sides. At temperatures below 18 they can be columnar, hexagonal, or fernlike. Virtually all have six sides. That hexagonal tendency is something of a mystery, although some scientists suggest it is produced by electrical charges in the crystals, while others say it is basic to the molecular structure of water molecules. The atoms in a molecule of H20 are arranged, in physicist Hans C. von Baeyer’s graphic description, “with two little hydrogens stuck onto a big oxygen like ears on a Mickey Mouse’s head.” Scientists like von Baeyer believe that the angle at which the hydrogen molecules protrude from the oxygen atom–about 120 degrees–causes snow crystals to grow to a six-pointed symmetry that repeats the molecular structure of water.
Read on for much more including whether or not two snow crystals are alike, heavy snowfalls and snow words & myths.
December 5, 2013
The Weather Notebook has this to say about Ice Volcanoes:
Ice volcanoes can form during winter on the Great Lakes. They are not lava-spewing mountains of ice, but water-spouting ice cones.
As winter ice begins to build along the shores of large lakes such as Lake Superior, it is jostled, broken, and shifted by the winds and wave motions on the waters. When winds blow onshore, they can build an ice shelf, a jumble of ice chunks that anchors on the shore but extends some distance back into the water. Amongst the numerous ice blocks comprising a shelf, many open tunnels lead back to the lake waters.
To build a good ice volcano cone, the surface air temperature must be several degrees below freezing and lake waves should be several feet high and breaking onshore. As the waves strike the edge of the ice shelf, pulses of wave energy flow beneath the ice. Upon reaching the open end of a tunnel, the wave forces water to erupt out through the ice. If the hole has been covered with snow, the eruption may spray snow outward like a volcanic gas cloud.
As the ejected water falls back onto the ice, it quickly freezes and begins the formation of an ice cone, a process very similar to the building of a lava cone surrounding a geologic volcanic vent. A study of ice volcanoes on Lake Superior’s southern shore by students from Michigan Tech measured ice cones ranging from three to 25 feet in height.
Like rock volcanoes, ice volcano vents can heal over and become dormant during periods of low wave action. They lie in wait for a strong wave surge to awaken them back to explosive activity.
More icy goodness on Michigan in Pictures.
December 4, 2013
November 27, 2013
While the blizzardy blowing going on this morning in northern Michigan and the U.P. isn’t the best for “over the rivering”, it is ensuring that Many of Michigan’s ski resorts get to enjoy their earliest opening date in tears with plenty of white gold!
If you’re looking to check out Michigan’s ski scene, head over to goskimichigan.com from the Michigan Snowsports Industries Association. They have updates from Michigan ski resorts on snow conditions & planned opening dates. Their Discover Michigan Skiing program will give you a beginner lesson, ski or snowboard rental equipment and a beginner-area ski lift pass or cross-country trail pass at 23 Michigan ski facilities! It’s available through January 31 and costs just $20 for cross-country skiing, $30 for downhill skiing and $40 for snowboarding. While you’re there, check Cold Is Cool – a promotion that gives every Michigan 4th Grader FREE skiing at participating Michigan resorts.
This photo from yesterday (Nov 26, 2013) shows Crystal Mountain’s new PistenBully Winch Cat roaring up the ski hill “Buck” – they open for skiing and riding Thanksgiving Day! Stay up to date with their ski & snow report.
More Michigan skiing on Michigan in Pictures!
November 23, 2013
Many in Michigan are waking up to frigid temps, high wind and snow – the perfect conditions for lake effect snow. Meteorologist Robert J. Ruhf has an excellent article on Lake-Effect Precipitation in Michigan that explains lake effect snow and rain are common in Michigan, especially in late fall and early winter as cold polar air moves across the warmer Great Lakes.
The unfrozen waters are relatively warm when compared with the temperature of the wintertime air mass. Therefore, the temperature of the air that comes into contact with the water increases. The warmed air expands and become less dense, which causes it to rise. This is an “unstable” situation. As the air rises, the temperature decreases until it reaches the dew point, which is the temperature at which the air becomes saturated.. Ice crystals or water droplets will then begin to collect until the force of gravity pulls them down. The result is “lake-effect” precipitation. When the cP air mass is very cold, as is often the case between December and February, the precipitation falls as snow. During late autumn, however, the polar air mass may be warm enough for the precipitation to fall in the form of rain.
“Lake-effect” precipitation can cause substantial intensification of snowfall amounts in very narrow bands, often referred to as “snow belts,” along the leeward (downwind) shores of the Great Lakes. The prevailing wind direction in the Great Lakes region is westerly; therefore, most “lake-effect” precipitation events occur to the east of the lakes.
…An interesting feature of “lake-effect” is that the heaviest bands of snow do not usually occur along the immediate shoreline, but tend to fall several miles inland. Snowfall accumulations are enhanced inland because the air experiences more uplift when it is forced over hills and higher terrain.
Read on to learn lots more about lake effect snow in Michigan including four narrow bands - Keweenaw Peninsula, Leelanau Peninsula, the Thumb and the southwest Lower Peninsula - where geographic features and the shape of the shoreline contribute to more intense snowfall. Hang on to your hats – winter is here!
Need a winter background?
November 9, 2013
In Farmers’ Almanac prediction: valid winter forecast or ‘darts at a dartboard’?, the Great Lakes Echo explores the accuracy of the venerable Farmers’ Almanac, writing:
…this year, like many before, bloggers, newspapers and local TV stations alike are abuzz with the Almanac’s prediction for winter 2014 – particularly a notably bitter, cold, precipitous winter for the Midwest and most of the Great Lakes region.
“This winter is shaping up to be a rough one,” the almanac reports.
So how much weight does this prediction hold?
“The value of the Farmers’ Almanac in terms of weather forecasting is no better than a comic book,” says Detroit-based meteorologist Paul Gross. “If we knew the forecast a year in advance, we’d be utilizing that knowledge by now.”
The Almanac, which famously keeps its weather predicting methods rather hush-hush, claims to be 80 percent accurate – although the lack of concrete evidence proving that claim draws some skepticism.
The Almanac also makes a questionable remark about the relationship between global warming and a winter with heavy snow.
“Brrrrr!” says the excerpt. “It looks like global warming will soon be taking a vacation to make room for Old Man Winter.”
Heavy snow in winter means quite the opposite in regards to global warming, says Gross. “What people don’t understand is that global warming means that more ocean water is evaporated into the atmosphere,” he said. “And that water vapor in the atmosphere is what becomes available to storms to create precipitation.”
Global warming isn’t “taking a vacation” to make way for the heavy precipitation, Gross said. Rather, a warming climate cause increased precipitation. “It’s shocking, but four of Detroit’s top 10 snowiest winters in history have occurred since 2002,” he said.
They add that the Almanac’s prediction does appear to be somewhat in line with predictions like the National Oceanic and Atmospheric Adminstration’s. Read on for more at the Echo.
More weather on Michigan in Pictures.
November 1, 2013
“Autumn is the greatest reminder: It reminds us how dreamlike beauties our earth has and it reminds us how all these beautiful dreams can easily vanish!”
~Mehmet Murat ildan
Michigan has already seen its first snows of the winter, and we all know it won’t be long before that dusting of snow settles in. I’m not saying that to depress anyone – just to remind you to take a moment to soak up the last of the fall color wherever you can find it this weekend!
March 16, 2013
Since I’m up in the Pictured Rocks, I thought it would be a good time to share this video of Lake Superior waves at Pictured Rocks in winter by Lars Jensen.
More from the Pictured Rocks National Lakeshore on Michigan in Pictures including a feature from Lars on Miners Castle from the winter of 2006!