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Showing posts from January, 2007

The Opportunist

We own three properties across this varied country, each in a different life zone: a suburban home in central Missouri, a small farm in the semi-arid landscape of the Colorado Front Range and a condo on a barrier island off Sarasota, Florida. There is only one mammal, other than humans, that I regularly see in all of these settings: the common raccoon. While they prefer riparian woodlands, raccoons adapt to a wide variety of urban and rural habitats.

After mating in January or February, the female usually selects a den in a tree cavity or natural cave. However, as many of us know, raccoons also settle for attics, chimneys, barns and abandoned buildings. A litter of kits, averaging 4-5, are born in April or May and stay with their mom through the summer; by fall, they are able to fend for themselves and some females will actually breed that first winter. Raccoons are omniverous, feeding on berries, nuts, corn, eggs, insects, crayfish, amphibians, carrion and small mammals. They feast on…

Goddess of the Sky

Bright, beautiful Venus graced the southwest sky last evening. Named by the Romans for their Goddess of Love, Venus is the brightest object in the night sky (other than our moon). Since its nearly circular orbit is closer to the sun (an average radius of 49 million miles, compared to 93 million miles for Earth), from our vantage point, Venus never ventures more than 47 degrees from the sun. As a result, it is at its brightest just before dawn (in the southeast sky) or just after sunset (in the southwest sky) and has long been known as the Morning Star or Evening Star, respectively.

Our sister planet, which is only slightly smaller than the Earth, has become the poster child for greenhouse warming. Venus has a dense atmosphere of carbon dioxide, which is primarily responsible for its surface temperature of 400 degrees C; it is actually warmer than Mercury even though its orbit is nearly twice as far from the sun. Another unusual feature of Venus is its slow rotation; while it orbits the…

Inversion

Salt Lake City has been enveloped in a soup of smog for the past few days. While not uncommon there during the colder months, this "inversion" has been especially severe and prolonged; persons with chronic lung conditions are advised to remain indoors and the airport has been diverting some flights due to low visibility.

Inversions occur when a layer of cold air becomes trapped beneath warmer air, impairing the usual mixing that disperses moisture and pollutants. Salt Lake City sits in a broad valley between two mountain ranges; cold air sinks from these highlands during the night and settles in the basin. When high pressure develops over the region and winds are light, an inversion often develops. Climb a few hundred feet into the adjacent mountains and you leave the brown smog, entering clear, sunny, warmer air.

Inversions are common in many western cities, which usually sit along rivers and often have nearby mountain ranges. Before man arrived with his fireplaces, auto…

Man and the Universe

Current scientific evidence indicates that the Universe is 13.7 billion years old. If we telescope this span of time into a single year, then the Big Bang occurs in the first second of January 1. Each succeeding day covers 37.5 million years; each hour represents 1.5 million years, 1 minute equals 26,000 years and 433 years come and go in one second; the life expectancy of a human being is less than 0.2 second.

On our imaginary calender, the Milky Way Galaxy appears on February 14, the Sun forms on August 20 and the Earth develops on August 30. Life first appears on Earth on September 16. Shelled marine life evolves by December 16, the first land plants appear on 12/19, ancestral amphibians grace the scene on 12/21 and the earliest reptiles turn up on 12/22. Dinosaurs rule the earth from December 26 through December 30; during their reign, the first mammals appear on December 26 and ancestral primates evolve by December 30. Humans do not inhabit the earth until the last 5 minute…

On Behalf of Immigrants

Veteran birders and conservationists often despise non-native species such as starlings, house sparrows and pigeons. While I can understand their anger at those humans who thoughtlessly introduced these birds to North America, one has to admire the tenacity and adaptability of the birds themselves. Furthermore, much of their success is tied to non-native environments that man has created: city parks, landfills, feedlots and crop fields come to mind.

In this era of immigrant bashing, it is important to remember that humans are not native to North America. We evolved in Africa some 125,000 years ago and only reached this Continent about 25,000 years ago; even Native Americans are not truly native. We are all children of immigrants.

The Northeast Snowbelt

The northern edge of the Appalachian Plateau begins in the Catskills, runs through western New York, crosses the northwest tip of Pennsylvania and then turns southwestward just east of Metro Cleveland. The counties that sit atop this highland are known for their prodigious lake-effect snowfalls, which generally occur in the fall and early winter.

As cold, north winds blow across Lakes Erie and Ontario, they become humidified. Forced to rise by the Appalachian front, this moisture-laden air cools below its dewpoint, dropping heavy amounts of snow on the border zone; snowfalls of 2 to 3 feet are not uncommon. This snow machine generally shuts down by mid December as the Great Lakes freeze over. However, a mild early winter across the Northeast and Upper Midwest have kept the Lakes open and, as an Arctic Front passed through yesterday, heavy, lake-effect snows followed. As our climate warms, this pattern will likely continue and the Snowbelt will earn its name from October through March.

Wood Smoke

During winter, nature's earthy aromas are suppressed by the cold, dry air and the frozen ground. One of the few smells that we associate with winter is that of wood smoke, which, I suspect, is appealing to most of us.

Anthropologists tell us that Homo erectus was the first hominid to create and use fire, a skill learned more than 1 million years before our own species evolved. Fire was vital to prehistoric man, providing light, heat and a means of protection. It seems likely that the smell of wood smoke is imprinted on the collective human conciousness, triggering a sense of comfort and safety. For we humans, wood smoke is the aroma of home.

Hot Spots

Most of the Earth's volcanoes occur in areas where oceanic plates are subducting beneath other tectonic plates; this is especially common throughout the Pacific Rim (the Andes, Cascades, Aleutians and Indonesian islands are all volcanic). They also occur along the oceanic ridges, in continental rift zones and at "hot spots."

The latter are areas where mantle plumes are melting the deep basement rocks of the oceanic and continental plates, producing pockets of magma. This liquified rock reaches the surface as volcanic formations. Yellowstone National Park, the Galapagos Islands and the Hawaiian Islands are all examples of hot spots. In the case of Hawaii, the Pacific plate has been moving northwestward over the hot spot, resulting in a chain of 20 islands and atolls. The big island of Hawaii is now over this mantle plume and is thus the site of active volcanic activity.

Recent scientific evidence suggests that these hot spots are not stationary features and have moved about…

Drought Relief

For the past week, the subtropical jet stream has been drawing Pacific moisture into the American southwest; with cold air in place, this has produced the first significant snowfalls in the mountains of Arizona and New Mexico in the past few years. Now, the jet has angled more to the east, sending a plume of moisture across Mexico and into Texas. Heavy rains are forecast for western and central Texas, a welcome though temporary relief from a multi-year drought.

It is humbling to realize how much our lives are affected by the fickle motion of air currents. Our rudimentary understanding of the forces that guide them leave us guessing at the severity of our winters and, as 2006 demonstrated, make the art of hurricane forecasting seem like pure folly.

From Sand to Snow

Ah, the wonders of modern travel. One day you are walking on the warm sands of southern Florida and the next you are shoveling snow in the cold, gray Midwest. Our visit to the Gulf was all too short but I still prefer life in the Temperate Zone, warts and all.

The days are noticably longer now and we expect a week of 30s and 40s, with intermittent, sloppy snow; not near as nice as the sunny 70s of Florida but a significant improvement from the ice and single digits of last week. Within another month, early crocuses and spring peepers will make their appearance, reassuring us that spring is on the way.

Longboat

Our condo on Longboat Key, Florida, sits on a shallow inlet of Sarasota Bay. While the gulf-front homes, with their view of the surf and sunset, are more "desirable" and expensive, I prefer our view of the bay, with its fabulous diversity of wildlife.

Brown pelicans, ospreys, cormorants, anhingas, laughing gulls and various terns fish on the open waters; during the colder months, they are joined by American white pelicans, common loons, horned grebes, red-breasted mergansers and bald eagles. Dolphins explore the boat channel throughout the year and manatees are especially common in winter, when the bay waters are warmer than the Gulf. At low tide, shallows and mudflats rim the inlet, attracting mixed flocks of herons, egrets, ibis, roseate spoonbills and wood storks. Without these wild creatures, our place in the sun would feel empty.

Deep Freeze

The core of the Arctic air has now moved into the southern Plains as the leading front pushed on to the east. This frigid air covers a large area, from California to the Appalachians. Today's morning lows included 41 in Los Angeles, 21 in Tucson and 12 in Kansas City. We should reach 23 this afternoon and expect lows in the single digits for the next few days.

The good news is that the leading cold front, which has been producing snow, sleet and freezing rain, has finally left our area. Cold is easier to take without the ice-covered roads and walkways. It's also easier to accept when you have plans to visit Florida; we're heading down to Longboat Key tomorrow!

An Uncommon Visitor

Backyard feeders attract the usual mix of songbirds on most days. Chickadees, cardinals, house finches, house sparrows, titmice, downy woodpeckers, goldfinches, blue jays, nuthatches and mourning doves are among the more common visitors. During the colder months, they are joined by juncos, white-throated sparrows, hairy woodpeckers and purple finches.

When snow or ice cover the fields and coat the trees, the number of visitors at backyard feeders can swell dramatically. In addition, more reclusive species are often enticed to join them. Today, a fox sparrow turned up at our feeder; though a fairly common winter resident in Missouri, this handsome sparrow prefers dense thickets, where he usually feeds alone or in small groups. Noticeably larger than the other sparrows and juncos beneath the feeder, he has a gray face, heavily-streaked breast and rust-colored tail. While it often takes a winter storm to send him by, the fox sparrow is always a welcome visitor.

Saved by the Cold

So far, Central Missouri has been spared the worse of this latest winter storm. Ironically, this is because we were covered by more cold air than areas to our south and east. As a result, we have received an inch or two of sleet but have had very little freezing rain.

As the warm, moist air from the Gulf over-rides the dense, cold Arctic air, precipitation is triggered in the higher layers. If the lower, cold layer is thick enough, this rain freezes before hitting the ground, producing a sleet storm; sleet can make travel difficult but, since it bounces off trees and wires, it does not cause significant damage or power outages. On the other hand, if the cold zone is relatively thin, the rain does not freeze until it strikes the trees, wires, ground and roadways. Such freezing rain can be disastrous, bringing down tree limbs and power lines as the ice builds up on these structures. Sleet never looked so good!

Ice Storm

Arctic air is plunging southward through the Plains and the leading edge of this cold front will stretch from central Oklahoma to western Illinois by late this afternoon. Low pressure is expected to move eastward along this borderline, pumping warm, moist air over the frigid, surface air, the perfect set up for an ice storm.

Severe icing conditions are forecast for northeastern Oklahoma, much of southern and central Missouri and west-central Illinois. Widespread power outages are expected and travel may grind to a halt. Just another reminder that our mild winter can disappear at the drop of a jet stream!

Spectacle on the Plains

Driving back from Denver, a heavy snowpack still covered eastern Colorado, western Kansas and, I assume, western Nebraska. About 10 miles west of WaKeeney, the snow began to thin out and huge flocks of longspurs, horned larks, meadowlarks and other grassland birds began to appear along the highway. Attracted by these unusual concentrations of songbirds, kestrels, falcons and harriers were common, often knifing through the flocks like sharks through schools of fish. Beyond WaKeeney, the spectacle was over.

Clearly, the heavy snows had forced these birds from their usual wintering grounds and they had settled along the edge of the snowfield, where they first encountered adequate supplies of food. As the snow retreats, these grassland species will disperse throughout their usual range and their predators will have to work for a living again.

Blood on the Snow

During my brief visit to our Colorado farm, I was surprised not to see either of the two fox that usually den beneath our barn. I assumed that the heavy snow may had either encouraged them to den up for a few days or sent them down to the river where plenty of prey could be found. These assumptions were dashed yesterday morning when I looked out the front window and saw a large patch of blood on the snow. Feathers, numerous paw prints and the mangled carcass of a Canada goose completed the story.

Such a gruesome scene is unlikely to be shown on the popular nature programs. "Civilized humans" prefer to get their violence and gore via action movies; they generally want their nature shows to be sanitized, concentrating on the beauty and grandeur of the natural world. While viewers know that predators must hunt and kill to survive, producers usually "protect their sensitivities" by cutting away from the final events. But the beauty of nature lies in its diversity,…

Looking at the Past

Cold, clear winter nights usually provide the best conditions for star gazing and last night was no exception. At 9 PM, Orion, perhaps the most well-known winter constellation, was high in the southern sky and Sirius, the brightest star in the sky, shimmered to its southeast.

Orion, which resembled a hunter to ancient civilizations, is easily recognized as a prominant rectangle (shoulders and feet), bisected by a three-star belt; a less-obvious sword hangs below the belt. The left (east) shoulder is Betelgeuse, a red super giant that is 900 times the diameter of our sun. Orion's right (west) foot is Rigel, a blue-white super giant that is the 7th brightest star in the sky. If you look closely, you will see a fuzzy area near the midpoint of Orion's sword; this is the Orion nebula, a star nursery. Of course, the association of these stars is purely a human interpretation; the component stars vary dramatically in their distance from the earth and the four corners of Orion ar…

Love in the Trees

The fox squirrels are chasing each other through our Siberian elms today, demonstrating their impressive acrobatic skills. But their friskiness is more than a celebration of this warm, sunny day; January is mating season for our native tree squirrels and the males become very active, pursuing females and chasing away their competition.

The young are born in February or early March but will remain in the tree cavity or leaf nest for a few weeks. By late April they will be ready to fend for themselves and the adult female may have a second litter in early summer. As we all know, they will spend the rest of the year lounging in trees, feeding on buds, digging up bulbs, hording acorns, gnawing on walnuts, raiding bird feeders and driving the pet dogs crazy.

Chinooks

The Colorado Front Range, from Wyoming to Colorado Springs, is under a high wind warning tonight. A new Pacific storm is pushing in from the northwest, forcing winds over the Continental Divide. The high passes are expecting wind speeds near 100 miles per hour and we should receive gusts as high as 50 in Denver. Snow will fall west of the Divide but the Metro area will be spared this round.

As this air descends along the east slope, it compresses and warms. Such Chinook winds, known as "snow eaters," bring a respite from the winter chill and usually melt more snow than the low January sun. Lows tonight will remain near freezing, 15 degrees warmer than last night, and highs tomorrow should reach the upper 40s. Maybe the driveway will open up.

Driving Back to Winter

Another March-like morning enveloped mid Missouri as I left Columbia and headed for our farm in Metro Denver. A waning moon was high in the western sky and puffy clouds drifted northward on a balmy south breeze. By the time I reached Kansas, the moon had set and the air had lost its humidity. Nevertheless, bright sunshine softened the bite of the northwest wind and temperatures hovered in the low forties.

The Flint Hills had their usual, dry winter appearance but, nearing Abilene, meltwater puddles lined the highway. The first patches of snow showed up just east of Salina, where the valley fields had become shallow wetlands. Flashing signs, perhaps sponsored by the Salina hotels, warned of winter conditions ahead and a convoy of Power Company trucks headed west along the Interstate. Indeed, the snow became more widespread as I entered central Kansas and, beyond WaKeeney, the bare areas disappeared. Dunes of snow lined the highway in western Kansas and the snowpack peaked on the plains …

Then and Now

Novice geologists often confuse the age of landforms with the age of the rocks that comprise them. For example, Mammoth Cave, in Kentucky, is carved out of Mississippian limestone, deposited in shallow seas some 320 million years ago; however, most of the cave formed over the past 2 million years, eroded by the wet climate of the Pleistocene. In like manner, the Entrada Sandstone, which forms the arches in Arches National Park, was deposited during the Jurassic Period, about 150 million years ago; however, the arches have been molded by wind and water since the onset of Miocene Uplift, which began 20 million years ago.

Towers of limestone, deposited in a Cretaceous Sea, now grace the dry plains of Kansas and the summit of Mt. Everest, earth's highest point, is composed of marine sediments, pushed landward and upward as India collided with the Eurasian plate, 50 million years ago. So, as you gaze upon our modern landscapes, know that they are the product of geologic events and erosi…

Inland Gulfstream

Southerly winds, produced by a combination of high pressure off the Carolina coast and a low pressure trough over Texas, are sending a plume of rain up the Mississippi Valley. Laden with Gulf moisture, this warm flow will keep temperatures near 50 as far north as Chicago. Heavy rain is forecast for Louisiana and Arkansas, with lighter amounts further inland.

The next Pacific storm, now brewing in northern California, will sweep eastward over the next few days, nudging these spring-like conditions to the Atlantic coast and shutting off our balmy flow from the Gulf. Afterall, it is January.

Solitude Lost

We parents want what is best for our children and hope that they will share our values. Yet, each generation sees something in the next that disturbs them and, in my case, I worry that the've lost the desire for solitude.

In this era of cell phones, beepers, instant messaging and wireless internet, the emphasis is on staying connected. One seldom encounters a young adult or teen who is walking down the street without a cell phone pressed to their ear. Worse yet, the same behavior is seen on our trails and along our beaches; only a lost signal gives them the chance to enjoy their natural surroundings. Perhaps this will become the new definition of wilderness: an area inaccessible to cell phone signals.

The Ozarks

Driving south from Jefferson City, Missouri, one soon encounters the first ridge of the Ozarks. Extending across southern Missouri, northern Arkansas, northeastern Oklahoma and extreme southeastern Kansas, the Ozarks are an uplifted plateau of horizontal, Paleozoic sediments that have been dissected into a maze of ridges and valleys by tributaries of the Missouri and Arkansas Rivers. The Ozark Plateau rose in concert with the St. Francois Mountains of southeastern Missouri, some 300 million years ago; the latter have eroded from a core of ancient, Precambrian granite and represent the highest elevations in the State.

Since most of the Ozark Plateau is composed of soluble limestones and dolomites, caves, springs, sinkholes, natural bridges and other karst features are common throughout the region. Its many streams are popular for fishing, kayaking and rafting and the Plateau's oak-hickory-pine forests are home to gray fox, wild turkey and black bear.

Day Eleven

Rooted in the Roman and Gregorian calenders, the designation of January 1 as New Year's Day is a product of political and religious rangling over the years. More in tune with the forces of nature, the ancient Greeks accepted the winter solstice as the beginning of their new year.

Afterall, life on earth is dependent upon light and heat from the sun and the solstice is a rebirth of the solar cycle. Of course, for those in the southern Hemisphere, this event occurs at the time of our summer solstice (on or about June 21). So, while this is the first day of the human year, it is day eleven (or so) in the natural cycle of our Hemisphere.