~tentang saya~

Halo teman - teman !!

Nama saya adalah fauzan tapi panggil saja saya ozan

Hobi saya adalah main Game CF INDONESIA

Warnet kesukaan saya kendarinet di KENDARI (T_T) 

Pertama kali saya dia diajar memainkan komputer bersama Pamanku

Saya bermain Revolt di komputer

Ketika saya besar umur 8 tahun saya sudah kuasai ilmu komputer!!

Pertama - tama saya bermain game online ya itu PB 

Kedua saya bermain game Cross fire online indonesia

Ketiga ....... nanti aja ya kita bahas lagi!! 

Exercise Canyon

Waterton Canyon, which incises the foothills southwest of Denver, represents the South Platte's final journey through the Rocky Mountains before it rumbles onto the Colorado Piedmont.  Harboring a wealth of scenic rock formations and home to a wide variety of Transition Zone flora and fauna, the canyon has long been a popular destination for hikers, birders, fishermen and naturalists.  Over the past decade or so, it has also become a mecca for bikers and joggers, now comprising at least 75% of the visitors.

While these trail athletes surely enjoy the pristine landscape, at least in a holistic sense, I doubt they pay much attention to the varied plants and animals, focused as they are on distance and time.  As they turdge along, gasping and spitting, or whiz by on their trail bikes, I often wonder if they could identify even a handful of species that inhabit the canyon.  They surely notice the bighorn sheep, for which this refuge is well known, but a fleeting glance is probably sufficient.

In this age of obesity, I certainly have no objection to aerobic exercise.  But I suspect these bikers and joggers choose Waterton Canyon for its graded climb and known distance (6 miles to the Strontia Springs Dam); of course, they also enjoy group exercise and avoid the heavy auto traffic that occurs in other foothill canyons.  Some might conclude that I envy the youth and vitality of these athletes (which is surely true to some extent) but I am more inclined to pity their lack of interest in nature's bounty.  Dogs are not permitted in Waterton Canyon in order to protect the bighorn sheep; perhaps we should limit its use as an athletic training site in order to protect the natural milieu.

The Kaibab-Coconino Plateau

As the Paleozoic Era gave way to the Mesozoic, some 225 million years ago (MYA), an ovoid upwarping of Earth's crust developed in what is now northern Arizona.  Reinforced during the Laramide Orogeny (the formation of the Rockies, 70 MYA), this broad ridge was eventually covered by layers of Mesozoic and Tertiary sediments (both erosional and volcanic).  Late in the Tertiary Period, the Miocene-Pliocene Uplift (stretching from about 15-5 MYA) lifted the entire Colorado Plateau and its rim of mountain ranges another 5000 feet, increasing stream erosion across the Province.  Rising on the west side of the Continental Divide, the Colorado River flowed westward and gradually southward to enter the Sea of Cortez; en route, it crossed northern Arizona, entrenched in the younger sediments that covered the Kaibab-Coconino ridge.  As the Colorado Plateau rose beneath it, the river was forced to cut down through this ridge of Paleozoic rock (and the upper layer of the ancient Precambrian basement that lies beneath it).  Augmented by the wet climate of the Pleistocene (2 to 0.01 MYA), the Colorado thereby sculpted the Grand Canyon, the most spectacular chasm on our planet.

The ridge itself, oriented NNW to SSE, has since been uncovered by erosion.  Streams from its eastern edge drain directly into the Colorado (or into the Little Colorado south of the Grand Canyon), while its northwest flank drains to the Colorado via Kaibab Creek and its southwest flank feeds the Cataract River, another tributary of the Colorado.  The exposed ridge is composed primarily of Kaibab limestone overlying Coconino sandstone; that portion north of the Grand Canyon is known as the Kaibab Plateau while its segment south of the Canyon is referred to as the Coconino Plateau.  The rock strata of the plateau, deposited during the Permian Period, form the upper layers of the Grand Canyon

The Kaibab Plateau rises to elevations that exceed 9200 feet, supporting a rich forest of fir, spruce and aspen, giving way to ponderosa pine and then pinon-juniper woodlands at lower elevations.  The Coconino Plateau is 7400 feet above sea level at the south rim of the Grand Canyon and gradually lowers toward the west, south and east; it is covered primarily by ponderosa pine parklands.  South of the Coconino Plateau, the landscape is dominated by the high peaks and scattered cones of the San Francisco Volcanic Field, including Humphreys Peak (12,633 feet), the highest point in Arizona.

Prairie Racerunners

Closely related to the six-lined racerunner of the Mid-Atlantic and Southeastern U.S., the prairie racerunner is found from northwestern Indiana and southern Wisconsin, westward to southern Wyoming and southward to Arkansas, West Texas and New Mexico.  Favoring dry, sandy soil and hot weather, these lizards inhabit prairie grasslands, abandoned farms, glades and rocky hillsides; attracted to disturbed areas, they are known to spread along power line swaths and railroad lines.  Here in Colorado, prairie racerunners are abundant from the High Plains to the shrub zone of the lower Front Range foothills.

Emerging from hibernation in late April or May, prairie racerunners are best observed during the morning and early afternoon hours of June and July, dashing across trails or clearings and disappearing into clumps of vegetation to snare prey or to avoid predators.  Their long tail, twice the length of their body, is thought to serve as a counter-balance as they zig-zag at speeds up to 18 miles per hour.  Mating occurs by late spring and five eggs are generally produced; as with most lizards, the hatchlings are miniature replicas of the adults and must fend for themselves.  While a second brood may be produced within a few weeks, adult prairie racerunners begin to hibernate by late August or early September; the young, needing more time to generate fat stores, wait until late September or October to settle in their winter burrows (depending on their home latitude).

Feasting on a wide variety of insects and other invertebrates during their brief season of activity, prairie racerunners may fall victim to grassland hawks, prairie falcons, burrowing owls, fox, coyotes, roadrunners, magpies and a variety of snakes.  Using shallow burrows during the warmer months, they dig a deeper channel with a terminal chamber for their prolonged hibernation; during that time, in sharp contrast to their frenzied life above ground, their metabolic rate falls dramatically and they rely on fat deposits to fuel their survival.  If they make it through their first winter, adult prairie racerunners are thought to have a natural life span of 4-5 years.

Front Range Oasis

While those of us who live along the Colorado Front Range enjoy abundant sunshine and a mild, semiarid climate, there is plenty of aquatic habitat along the urban corridor.  One of the best places to observe water-loving birds and mammals is South Platte Park, which stretches across the river's floodplain from the northern edge of Chatfield Reservoir State Park to the outskirts of downtown Littleton.  A mosaic of ponds, lakes, wetlands, meadows and riparian woodlands, the Park is accessed by a paved bikeway, its parallel walking path and a number of adjoining trail loops.  An Interpretive Center, west of Santa Fe Drive and north of Mineral, introduces visitors to the varied fauna and flora of the Park.

On this mild, clear morning, the refuge was teeming with birds, including many that non-Coloradans might not associate with our State.  A dozen American white pelicans moved among the lakes or fished in the shallows, joined by a large number of double-crested cormorants, scattered great blue herons, a pair of snowy egrets, a flotilla of common mergansers, noisy flocks of Canada geese and a varied assortment of ducks (primarily mallards, gadwall and wood ducks).  Tree and barn swallows swooped above the ponds, a Swainson's hawk circled overhead, belted kingfishers chattered along the river and a wide assortment of songbirds moved among the trees and cattails; these included yellow warblers, common yellowthroats, American and lesser goldfinches, western wood pewees, northern orioles, house wrens, northern flickers, downy woodpeckers and those ever-vocal red-winged blackbirds.  A lone black-crowned night heron, spooked from his shadowy haunt, was my final sighting of the morning.

Though represented only by fox squirrels, cottontails and black-tailed prairie dogs this morning, a variety of mammals also inhabit the Park and are best seen at dawn or dusk.  Among these residents are mule and white-tailed deer, red fox, coyotes, beaver, muskrats, raccoons, striped skunks,  meadow voles and deer mice; mountain lions and black bear are potential visitors but are rarely encountered.

Monsoon Relief

Returning to our Littleton, Colorado, farm today, I found that early monsoon rains have revitalized the landscape.  Indeed, over the past few days, heavy rains have moved northward across the Front Range, bringing much needed rain to the tinder-dry mountain forests and welcome moisture to the urban corridor.  While some flooding, mudslides and sinkholes developed, the storms have reduced the wildfire risk to some degree and, so far, have not ignited any new fires.

The annual monsoon rains of the American Southwest result from a southerly flow that brings in moisture from both the Gulf of California and the Gulf of Mexico.  The engine for this wind pattern is high pressure over the Southern Plains that generally develops by early July and persists through much of August; winds move clockwise around that atmospheric ridge, sweeping moisture northward along its western rim.  Showers and thunderstorms are usually confined to the Desert Southwest and Four Corners Region early in the season, reaching the Colorado Front Range by late July and August.  Thanks to the dome of drought that has plagued the south-central and southeastern U.S. for several weeks, the Monsoon got an early start and Colorado, caught in its own drought after a mild, snow-starved winter and a warm, dry spring, has received an early and very welcome gift.

Unfortunately, the monsoon flow will be shut off for the rest of this week as high pressure builds in from the West, bringing another round of hot, dry weather to the State and blocking the southerly stream of moisture.  When the Southwest Monsoon might generate more relief is anyone's guess but its typical arrival date is still a week or two away.

Colorado's Black Canyon

Near the end of the Mesozoic Era, as the Cretaceous Sea retreated to the southeast, Colorado was a relatively flat landscape of wetlands, sandhills and primitive forest.  Then, about 70 million years ago (MYA), pressure within the North American craton crumpled up the Rocky Mountains, pushing ancient Precambrian rock up through the overlying Paleozoic and Mesozoic sediments.

As soon as they formed, the forces of erosion began to act on these new mountains, filling the intervening valleys with debris.  About 35 MYA, volcanism developed in central and southwestern Colorado, lifting the West Elk and San Juan Mountains; the copious ash, pumice and lava from these eruptions also coated the valleys and basins of that region.  By 10 MYA, the Gunnison River had formed; rising on the west side of the Continental Divide, in the Sawatch Range, and receiving large tributaries from the West Elk Mountains, to its north, and the San Juans, to its south, this river flowed west to join the Colorado.  Entrenched within the erosional and volcanic debris that had settled across the broad, intervening basin, the Gunnison was forced to cut into a ridge of Precambrian gneiss and schist, east of present day Montrose, that was buried within the sediments.  Since that time, the river has sculpted the Black Canyon of the Gunnison from that ancient rock, a process that was augmented during the cooler, wetter climate of the Pleistocene.

Almost 50 miles in length, the Black Canyon is up to 2720 feet deep and 1100 feet across at its rim; at river level, it is much narrower, only 40 feet wide in one area.  The Painted Wall, on the north flank of Black Canyon, is named for the light-colored lava rock that laces its surface and is the tallest cliff in Colorado, dropping 2250 feet.  Within the canyon, the Gunnison River drops 43 feet per mile, a grade that is almost six times steeper than the Colorado River's course within the Grand Canyon.  Named for its shaded walls, hidden from the sun by its deep and narrow topography, the Black Canyon of the Gunnison is protected within a National Park that stretches along its middle (and most spectacular) 14 miles.  Farther west, the Gunnison is thought to have carved Unaweep Canyon through the Uncompahgre Plateau, later diverted northward by a landslide to join the Colorado west of Grand Junction (see my blog on 12-27-10).

Looking at the Invisible

This week at CERN, the Organization for European Nuclear Research, near Geneva, Switzerland, nuclear physicists may have discovered the Higgs boson, first theorized to exist back in 1964.  Using the Large Hadron Collider, in operation for just two years, they smashed protons together at high velocity and found a particle that had never been observed with past forms of technology.  Based on their initial calculations, it is thought to be a transient manifestation of the cosmic soup that gives mass to the elementary particles.

If confirmed, this discovery will herald a new era in our understanding of the Universe, focusing on the dark energy and dark matter that, combined, make up over 95% of its content.  Indeed, the visible stars, planets, comets, asteroids and interstellar dust make up less than 1% of the Universe, with intergalactic gas accounting for 3.5% or so.  This week, we caught our first glimpse of the dark side and took our first step toward understanding the dark energy that is causing the Universe to expand at an increasing rate.

For most of us, the details of the Higgs boson discovery are difficult to understand.  Those who prefer to concentrate on the simplistic dogma of their chosen religion will dismiss the news as scientific heresay; after all, bosons are not mentioned in the Bible.  But for those hungry to understand the complex nature of our Universe, this discovery promises a new world of adventure.

A Stubborn Ridge

The dome of high pressure that has parked itself over the Heartland for the past two weeks shows no sign of abating.  Rather than drifting off to the east, it has backed into the Southern Plains; unfortunately, those of us in the lower Missouri and Mississippi Valleys remain within its grip.

Beneath this atmospheric ridge, the air is sinking and drying out, producing excessive heat and retarding cloud formation.  Storm systems are shunted along its outer rim, exacerbating drought within the dome while fueling violent weather at its periphery (as we saw in the Upper Midwest and Mid-Atlantic region last week).  On the positive side, this stubborn ridge may ignite the Monoon Season across the American Southwest, pulling in moisture from both the Gulf of California and the Gulf of Mexico as clockwise winds stream along its western rim.

Those of us caught within its boundaries can expect another week of hot, dry weather, with afternoon highs near 100 degrees F.  Beyond prolonging our personal discomfort, this dome of drought is taking a toll on forests and crop fields across the Heartland, stressing natural ecosystems and posing a serious challenge for farmers and ranchers.  Unless relief arrives in the form of a potent Canadian front, it may take a hurricane to dislodge this ridge.

The Heart of Champions

As the Olympic Trials wind down and national teams prepare for London, it is clear that there is something special about Olympic athletes.  Like others in their respective sport, they are talented and hard-working individuals who enjoy a good deal of support from family, friends and colleagues.  Yet, these Olympians seem to harbor traits that set them apart.

Despite their success and self-confidence, few (if any) are arrogant or egotistical.  Rather, their achievement reflects their competitive spirit, their courage in the face of adversity and, perhaps most importantly, an unwillingness to concede defeat.  This latter trait, which might be defined as heart, is found in all champions, from race horses to long-distance runners to heavyweight boxers.  When the margin of victory is razor thin or when endurance plays a major role, heart is especially vital.

Of course, this trait is not confined to sports.  While some owe their success to good fortune, most champions of human society possess this same competitive spirit; facing obstacles that discourage their rivals, they have the heart to persevere.  Heart is, indeed, a human trait which seems to require a delicate mix of genetic, familial and cultural factors.  Alas, in most individuals, it never reaches full expression. 

The Season of Insanity

Humans, tropical creatures that we are, have a healthy respect for winter,  Not naturally equipped to survive its wrath, we take shelter from winter's storms and tend to hibernate for much of its course.  While the cold, dark season may be depressing for some and does induce its fair share of injuries, winter keeps us on our guard and, for the most part, out of trouble.

Summer, on the other hand, that carefree season of vacations, picnics and outdoor recreation, is welcomed by most humans and its dangers are too often ignored.  But, contrary to what many believe, the summer heat causes far more deaths than does the winter chill.  The elderly, stressed by excessive heat and too often housed in poorly ventilated apartments, are the primary victims; ironically, young, healthy athletes are the other group at risk.  Driven on by macho coaches and drill sergeants or by their own sense of immortality, they work out or engage in sports on summer afternoons and, as we observe every year, some fall victim to heat stroke..  There is a popular misconception that exercising in the heat, drenched in sweat, is a more effective way to lose weight or to get in shape than is exercising during cooler parts of the day.  This, of course, is false and such behavior invites disaster.

Despite these admonitions, repeated throughout the summer by news and weather reporters, many will ignore the warnings and our current heat wave will be the last for some young athletes.  We may be designed for the tropics but there are limits to our capacity to dissipate heat.  Staying well hydrated is important but common sense is our best means of protection.

Life in the Universe

Current scientific evidence indicates that the Universe is 13.7 billion years old and that the galaxies formed 12 billion years ago.  Yet, our home star, the sun, is less than 5 billion years old, the Earth  formed just 4.6 billion years ago, unicellular life did not evolve on our planet until 3.6 billion years ago and we humans did not appear until 130,000 years ago.  Countless suns, their solar systems and the life that inhabited their planets likely evolved and disappeared long before our own sun and planet came into existence.

Among the 100 billion galaxies and trillions of stars that stretch across the ever-expanding Universe, there are surely millions of other planets that sustain life which, in many if not most cases, has progressed farther along the evolutionary tree than has life here on Earth.  In other words, it is almost a certainty that many human-like civilizations inhabit this Universe, most of which are more advanced than our own.

It is understandable that religious persons might find these rational facts too threatening to contemplate but it is disconcerting to hear scientists and scientific journalists question whether life exists elsewhere in the Universe.  Sitting here on our smallish planet that circles a modest-sized star on an outer band of a massive galaxy, it is absurd to suggest that we might be the only intelligent beings that inhabit the billions of galaxies.  The Universe surely teems with life and it is only our irrational self-importance that keeps us from embracing that fact.

Desert Heat in the Midwest

Records are falling across the American Midwest this week as the first major heat wave of the season invades our region.  High pressure over the Southern Plains, combined with a high pressure dome over the Southeast, has ushered in the hot, dry air; afternoon highs should top 100 degrees F in most areas.

In part, the extreme heat reflects the dryness of the air, as Gulf of Mexico moisture is kept at bay by the blocking high across the Southeast.  Dry air is more dense than humid air and is thus capable of reaching higher temperatures.  Indeed, winds are from the west-southwest and it feels more like Phoenix than Miami across the Heartland.

This heat wave will be slow to break as cloudless skies permit the intense sunshine to heat up the roofs and roadways in our towns and cities; this heat radiates into the air overnight, keeping the morning low well above average.  In addition, it will likely take a strong cold front to displace this high pressure ridge and none are forecast over the coming week.  For now, we'll confine our outdoor activities to the early morning and evening hours, hide from the afternoon sun and dream of October.

Industrial Obesity

Not long ago, we humans could not help but get plenty of exercise.  We had to hunt and spend long hours in the fields to obtain our food.  We had to chop wood to heat our homes and carry fresh water from the well or the river.  Travel was by foot or horseback and almost any task involved physical labor.  Perhaps most significant, we did not have televisions or computers to keep us inactive and entertained for hours at a time.

While many studies have demonstrated a higher rate of obesity in westernized countries, much of the focus has been on the dietary changes associated with our mechanized cultures.  But, while the excessive intake of sodas and cheeseburgers and donuts should raise concerns about our nutrition, it is, in my opinion, a less significant factor in the modern scourge of obesity than is our sedentary lifestyle.

Today, almost every technological advancement is designed to make our lives easier.  We may take our morning or evening stroll to get some exercise but most of our day is spent in cars, elevators and desk chairs.  Even farmers and construction workers have a wide range of machinery and tools that limit their physical labor.  Then, at the end of the day, exhausted and stressed, we plop in front of the television for several hours of mindless entertainment, getting up for a snack during commercial breaks.

The Nature of Volcanism

Volcanoes develop in areas where the heat from Earth's mantle melts the overlying crust.  This occurs along subduction zones, where one of the tectonic plates is dipping toward the mantle, in rift zones, where the crust is thinning (allowing the mantle to move upward) and at hotspots, where a mantle plume is rising into the crust.

Subduction volcanoes are the most widespread form of volcanism on Earth and are concentrated along the Pacific Rim where the Pacific Plate and its associated oceanic plates are dipping beneath the South American, North American, Eurasian and Australian Plates.  The Andes, the volcanoes of western Central America and Mexico, the Cascades, the Aleutians and the volcanoes along the western edge of the Pacific (Japan, Taiwan, Philippines, New Zealand) result from this process.  Other subduction volcanoes include those along the western and southern edge of Indonesia, the volcanic islands of the eastern Caribbean and Mt. Etna, on Sicily, one of the most active volcanoes on our planet.

Rift volcanoes include those above mid-oceanic ridges and those developing along rift valleys in continental crust.  Most oceanic ridge volcanoes are well below the surface of the sea and thus not readily observed; the major exception is the island nation of Iceland, which formed (and continues to form) above the mid-Atlantic ridge.  Continental rift volcanoes are seen along and within the East African Rift and the Rio Grande Rift of the American Southwest; they are also scattered throughout the Great Basin of the U.S. where the crust is being stretched (and thinned).  Hotspot volcanism occurs across the globe, along the ocean floor and beneath/within continental crust; the Hawaiian Islands, the Galapagos Islands, the Canary Islands, Yellowstone, the San Francisco Peaks of northern Arizona and the volcanic field of northeastern New Mexico are but a few examples.

The Lena River Delta

On satellite imagery, the Lena River Delta on the northern coast of Siberia gives the appearance of a fan coral, its braided channels and numerous lakes forming an intricate pattern across the Arctic tundra.  It is this landscape of countless pools and waterways that attracts huge congregations of loons, grebes, shorebirds and waterfowl to this 11,600 square mile wetland to nest and raise their young during the brief Arctic summer.

The Lena River, the second largest stream in Siberia, rises a few miles west of Lake Baikal, flowing northward and gradually eastward for 2700 miles to its delta on the Laptev Sea.  There it delivers tons of sediment each year, gradually enlarging and enriching the delta which is also an important spawining area for Arctic fish.  Nesting birds of note include red-necked grebes, four species of loon, whooper and tundra swans, bean geese, black brant, king and Steller's eiders, long-tailed ducks, Ross's and Sabine's gulls and numerous shorebird species.  Of course, willow grouse, rock ptarmigan, snowy owls, peregrine falcons and a wide variety of Arctic songbirds also inhabit the delta.  Resident mammals include gray wolves, Arctic fox, wolverines, least weasels, stoats, lemmings, tundra voles and reindeer; beluga whales, walruses and a variety of seals often visit the area.

Fortunately, most of this vast tundra wetland is protected within the Lena River Delta Nature Reserve, the largest nature preserve in Russia.  Visited only by the most adventurous naturalists, this spectacular but remote site is relatively free of human disturbance; nevertheless, the Lena, like all rivers on our planet, is tainted by pollutants from agriculture, mining, industry and sewage and their long term effects on the delta ecosystem is yet to be determined.

Dubious Debby

After forming in the eastern Gulf of Mexico over the past 48 hours, Tropical Storm Debby is going nowhere fast.  Parked west of Tampa and south of Panama City, she seems to be teasing the National Hurricane Center with her uncertain intentions.

The question is whether a weak cold front dropping through the Southeast will pick up the storm and shunt it northeastward, across Florida, or whether Debby will drift westward, gathering strength over the warm waters of the Gulf before impacting Texas.  Other computer models suggest that the storm might exit to the north, crossing Louisiana, Alabama or Mississippi.

Currently raking the western edge of Florida with heavy rains and high surf, Debby is a lopsided Tropical Storm, its center of circulation west of the rain bands.  This reflects the presence of upper level winds, crossing the storm from southwest to northeast and keeping the thunderstorms along its eastern and northern rim.  Should the storm remain in the Gulf and drift westward, it may escape this wind shear, allowing a closed system to develop (with thunderstorm bands circling the center of low pressure).  Such architecture is essential to the formation of hurricanes and it remains possible that this tropical storm could become Hurricane Debby in the western Gulf.  Time will tell but, for now, she has the forecasters baffled.

Avalonia

There are few terranes that illustrate the science of plate tectonics and continental drift better than Avalonia.  This micro-continent formed as a volcanic island arc along a subduction zone off the African Coast; at that time, late in the Precambrian Era, Africa was attached to the other southern continents to form Gondwana, which stretched across the South Pole.  During the Cambrian Period, some 530 million years ago (MYA), as shelled marine life was exploding in diversity, Avalonia rifted from the African Plate and drifted northward ahead of the Rheic Ocean, which opened between it and Gondwana.

Late in the Ordovician Period, some 450 MYA, Avalonia docked with Baltica, the craton that now underlies Scandinavia, Eastern Europe and western Russia.  This combined continental mass then collided with Laurentia (proto-North America) during the Silurian Period (440 MYA) as plants and animals were first colonizing the land; the collision forced up the Northern Appalachians, an event known as the Acadian Orogeny.  When the Earth's land masses merged into Pangea during the Permian Period, about 270 MYA, Avalonia was caught in the middle, compressed between the northern and southern continents.

As the Tethys Sea opened east to west, some 200 MYA,  Avalonia remained with Laurasia (the combined northern continents).  During the Jurassic (150 MYA), the Atlantic Ocean began to open, splitting Avalonia as it divided the North American and Eurasian Plates.  Today, fragments of Avalonia form coastal New England, Nova Scotia and the Avalon Peninsula of Newfoundland on the North American Continent; across the Atlantic, it is represented by Wales, England and the northern portion of Western Europe.  Small fragments of Avalonia have also been identified in South Carolina and along the western rim of the Iberian Peninsula.

Australia's Great Basin

The Lake Eyre Basin of east-central Australia is a vast topographic bowl within which streams drain toward the lowest part of the basin, never reaching the sea.  Covering 440,000 square miles from southwestern Queensland to South Australia and from the southeastern corner of the Northern Territory to the northwestern edge of New South Wales, most of it is dry, desert landscape through which ephemeral streams lead to Lake Eyre, in the southwest corner of the Basin.  Nearly dry and coated with salt flats most of the time, the lake fills only twice each Century (on average); composed of a large northern basin connected to a smaller southern basin by the Goyder Channel, Lake Eyre covers 3700 square miles and has an average depth of less than 10 feet (when full)  The lowest point of the lake basin, in Belt Bay of the northern portion, is 50 feet below sea level while the rim of the lake is 30 feet below the level of the sea.

The Lake Eyre Basin began to form about 200 million years ago, when Australia was part of Gondwanaland.  Tectonic forces caused the crust of this region to subside and, within another 100 million years, an arm of the sea invaded the basin; when uplift occurred along the northern and eastern margins of the basin, the sea drained away and rivers flowed across the region, depositing sediments on their way to the ocean.  During the middle of the Pleistocene, about 1 million years ago, uplift along the southern rim closed off the basin and all streams fed Lake Diers, the much larger predecessor of Lake Eyre (as Lake Bonneville preceded the Great Salt Lake in the U.S.).  As the climate became warmer and drier late in the Pleistocene and into the Holocene, the flow through the rivers diminished and eventually became sporadic.  Today, what little water reaches the lake is via three primary river systems: the Georgina River from the north, the Diamantia River from the northeast and Cooper Creek from the east.  Most streams from the west and northwest dry up before reaching Lake Eyre.

During those rare periods when monsoon rains or tropical storms fill Lake Eyre, this remote oasis attracts huge flocks of shorebirds, terns and Australian Pelicans that nest on the islands and feed in the shallows; how these birds know that the distant lake is full remains a mystery.  Lake Eyre National Park stretches along the east shore of the northern lake, just a short 435 mile drive north from Adelaide.  Major towns within the Lake Eyre Basin include Alice Springs, Mt. Isa, Longreach and Broken Hill.

Racing Past the Solstice

Last evening, the Northern Hemisphere crossed the summer solstice, its annual maximum tilt toward the sun.  Over the next six months, the sun will gradually retreat to the south and, in concert, our hours of sunlight will steadily diminish until we reach the winter solstice, on or about December 20.

It will take several weeks before we notice much change in the sunlight and several months before the longer nights take a toll on the summer heat.  Of course, the rate of change will be far more dramatic in the Arctic, sending shorebirds south by August and waterfowl in their wake.

Those of us who are not fond of hot, humid weather look forward to the cool, crisp weather of autumn and would like to accelerate the sun's retreat.  But it is the Earth's journey that governs our seasons, revolving around our home star on a tilted axis, steadily changing the angle of solar radiation that we receive.  Since we are already moving at 66,000 miles per hour to cover the 300 million miles between summer and winter solstices, a bit of patience seems to be in order.