Since time before memory people have used sunlight to make southwestern homes more livable. Many of the region’s characteristic cliff dwellings were carefully sited in places that are shaded in summer, but sunny in winter. That allowed natural heating to reduce the need for warming fuels.
Today savvy builders and homeowners are following in that tradition through clever design. Builders of new houses use passive solar design to bring sunlight in when it’s wanted and exclude it when it’s needed. And smart remodeling, too, can reduce heating and cooling bills.
This month, as nights grow long, Earth Notes pays homage to the sun and to some of the lesser-known ways it can fuel our lives.
It’s well known that photovoltaic solar panels produce clean, renewable energy. But a new study suggests that they can have an unintended consequence: in some climates, panels mounted on roofs may help keep interiors cool in summer and warm in winter.
Each year an average of 250 people are rescued from inside Grand Canyon. Many of them are hikers unprepared for the substantial temperature difference between the top of the rim and inside the canyon. Hikers can be surprised as they start with pleasant 70-degree temperatures at the top and approach a dangerous 100 degrees, or more, near the river.
Now the National Weather Service is working to address that gap in perceptions. With help from the Park Service, it installed two weather stations inside the Canyon: one at Indian Garden Campground, the other at Phantom Ranch.
When it comes to controlling the many non-native, invasive plants in northern Arizona, weed warriors call on every tactic in the book. As they seek to minimize the spread of a weed called diffuse knapweed, they’re turning to a tiny ally: a weevil that loves to eat knapweed seeds.
Diffuse knapweed is a low-growing shrub that originated on the Russian steppes. Since the 1980's, it’s taken over roadsides and pastures in the region. It’s a heavy seed producer and a tough competitor against native plants.
Flagstaff, AZ – Most of the Southwest is hardly turtle habitat. But in the scattered places where water rests in the open, or runs slowly, you can find them in mild weather.
In central Arizona, some of those aquatic animals are Sonoran mud turtles. As their name implies, most live mainly to the south. But Sonoran mud turtles do range as far north as Montezuma Well in the Verde Valley and into Oak and Beaver creeks, where they're fairly common.
Flagstaff, AZ – Toward the west end of Grand Canyon National Park, the South and North Bass trails plunge into wild canyon terrain. The trails are named for William Wallace Bass, a railroad man, miner, and entrepreneur who pioneered the area in the 1880s.
A Hoosier by birth, Bill Bass arrived in the small town of Williams, Arizona, in 1883, seeking better health. Out herding stray cattle one day, he got his first sight of the grandest canyon. "It nearly scared me to death," he declared.
Flagstaff, AZ – Bald eagles are a spectacular sight in Arizona's skies year round. Like the human population, they're more abundant in winter, when individuals from up north migrate south to take advantage of milder winter weather.
Come spring the state is also an important breeding ground for these emblematic birds - and since 1978 their success has hinged on a band of eagle-eyed human caretakers.
Flagstaff, AZ – Every year bull elk spend a lot of energy growing and hefting around antlers. These phenomenal structures, made purely of bone, have been known to grow at a rate of 1 inch per day during summer.
But is it worth it? Growing bony headgear that quickly requires enormous amounts of calcium. Some of it comes from plants, but most of it is provided by the bull elk's own rib bones. Only the healthiest of males can afford this diversion of minerals from their bodies so a big rack indicates an animal in good shape.
Flagstaff, AZ – It's tough to miss a century plant in full bloom. The plant's base of wide, pointed leaves sends up an enormously tall stalk that blooms brilliantly in spring. Also called agave or mescal, it's a plant that's common throughout the desert Southwest.
Native people once made use of agaves for fenceposts, needles and thread, soap, durable fibers and probably even paper. And wherever the plants grow, remains of pits used to cook them are sure to be found.
Flagstaff, AZ – Earth Notes: Valles Caldera Climate Study
As concerns mount about the world's and the region's climate, scientists have found a time machine in New Mexico that helps them better understand the past.
At the Valles Caldera National Preserve west of Los Alamos, researchers from Northern Arizona University and other institutions have been studying sediments laid down long ago in a now-dry lakebed. They have extracted a plug of materials from as deep as 260 feet underground.