Translate

Showing posts with label desert. Show all posts
Showing posts with label desert. Show all posts

Thursday, August 13, 2020

Crater Lake

This month is six years since my visit to fabulous Crater Lake National Park in Oregon. America's deepest lake at nearly 2000 feet in depth, it sits inside the collapsed caldera of an ancient volcano. Wizard Island near the west side of the lake is a volcano within a volcano. The lake is fed entirely by rain and snow. The amount falling in each year is nearly equal to what evaporates of leaks out the bottom. Crater Lake is what I can only describe as being impossibly blue. Pictures don't do it justice.

Crater Lake seen from West Rim Drive

In addition to the lake, the park also features forests, wildflower meadows, waterfalls, pumice deserts, cinder cones, and formations called pinnacles. The pumice deserts were formed by volcanic eruptions depositing pumice. Like sand, it drains very well so there is little moisture retained in the ground. Like in a true desert, only the hardiest plants can scratch out a living. 

Pumice desert

The pinnacles were originally volcanic steam vents. As gas and steam were released, moisture mixed with the surrounding ash and formed a thick cement. Mount Mazama, the ancient volcano that formed Crater Lake, had its last major eruption 7700 years ago. Following a massive eruption of ash and pumice, a huge explosion caused the mountain to collapse into itself. 

Wizard Island, a caldera within a caldera
Red Cinder Cone, a shadow of the volcanic past

While visiting Crater Lake, I got to do a bit of exploring. I started a sunset hike up The Watchman, one of the peaks along the crater's rim. I got turned around by an incoming thunderstorm. On another hike across the pumice prairie and through a burned forest, I turned around when I lost sight of the horizon with more storms in the forecast. I went down into a canyon along a mountain stream and back up, saw the pinnacles, a waterfall, and small meadow with varying degrees of wetness. Different wildflowers were growing in different areas due to elevation, soil, and moisture levels- a great example of zonation.

Some of the wildlife in the park includes Clark's nutcracker, golden mantled ground squirrels, mule deer, black bears, foxes, bobcats, and pika. I was lucky enough to see the ground squirrel, deer, gray jays, and a tiny frog.

After leaving Crater Lake, I headed to the coast and stayed at the Oregon Dunes. There was no activity at the Sea Lion Caves nearby. The next stop before going home was a quick visit to Mount Hood. I stank after a week in the woods without showers, but the adventure was worth it. This week's information comes from USGS and NPS. All photos are my own. I'll be taking a break for vacation and will return in September with a look at some hard workers, just in time for Labor Day.

Friday, August 7, 2020

Species of the Month

Introduction: World Elephant Day is next week, so to celebrate we’re profiling one of the world’s three
elephant species. In addition to the Asian elephant, did you know there are two different African
elephants? There’s the forest elephant and the more commonly known bush elephant, the August
Species of the Month.
African bush elephant (Wikipedia)
 
Scientific name: Loxodonta africana
Kingdom: Animalia (animals)
Class: Mammalia (mammals)
Order: Proboscidea (elephants)
Range: Central and southern Africa
Habitat: Savannah, forest, deserts
Lifespan: 60-70 years
Diet: Grasses, herbs, fruit, tree leaves, and tree twigs, roots, and bark
Predators: Lions, African wild dogs, hyenas, crocodiles, humans
Mother and calf (Wikimedia Commons)
Conservation Status: Elephants are listed as vulnerable on the IUCN red list. They are threatened under
the US Endangered Species Act.
Other Information: The African bush elephant is the largest land mammal in the world. An adult male
can weigh over six tons with a shoulder height of ten feet. Adult males live alone or in small groups,
while females and calves will form a larger herd led by a matriarch. Calves are raised communally
and are totally dependent on maternal care for several months. They reach full independence around
eight years old. Elephants don’t grow their tusks until after they’re a year old and the baby teeth fall
out. They also have a conveyor belt of six molars that wear out and fall out, allowing the next in line
to move forward. After losing the last molars, they can no longer eat properly. The large ears are great
for hearing, but also dissipate heat. Elephants are very mobile with a large range because of the
massive amount of food they need to eat. They can drink up to 50 gallons of water a day. Mud and
dust baths help them keep cool. Predators mainly go after small calves that fall behind the rest of the
herd. The greatest challenges facing elephants are caused by humans. Development has caused habitat
loss, and keep in mind these giants need a lot of room to roam. Poaching is also a serious threat. Most
elephants are confined to protected areas, limiting their population sizes. However, even at a protected
reserve elephants aren’t safe from poachers.
Young elephants at the watering hole (Sierra Club)
This week’s information comes from Animal Diversity Web.

Friday, July 17, 2020

Species of the Month

Introduction: Summer is road trip season, and many people do a road trip through any of
the western national parks. Most folks have a goal of seeing some wildlife, and one of the
iconic animals of the west is the bighorn sheep. They can be seen picking their way along
sheer cliffs in an amazing feat of agility, but I think more people are impressed by rams
crashing into each other head first as they battle for mating rights.
Scientific name: Ovis canadensis
Kingdom: Animalia (animals)
Bighorn ewe enjoying the view

Class: Mammalia (mammals)
Order: Artiodactyla (even-toed ungulates)
Range: Southern Canada south to Mexico, as far east as Texas
Habitat: Mountain meadows, rocky cliffs, deserts
Bighorn rams
Lifespan: 6-15 years, depending on population status
Diet: Grasses, sedges, forbs
Predators: Mountain lions, wolves, coyotes, bears, lynx
Conservation Status: California bighorn sheep subspecies is listed as endangered.
Bighorn lamb taking a break from frolicking
Other Information: There are three subspecies of bighorn sheep: Rocky Mountain, the most numerous
and widespread; California, which is endangered and can be found in the Sierras; and desert bighorn,
which live in the deserts of the US Southwest and Mexico.
Bighorns use rocky slopes and cliffs to avoid and evade predators. Specially built toes allow them to
navigate along ledges that are only inches wide, and excellent depth perception allows them to
accurately leap from one to another.
Bighorns have a shorter lifespan in dynamic populations with a high birth rate, on average 6 or 7 years.
Those in a more stable population with a lower birth rate tend to live longer, to longer than 10 years.
Ewes lounging at the top of a slope
Bighorns live in segregated herds, males in a smaller herd, while females and lambs (male and female)
form larger herds. The herds mingle during the rut, which takes place in fall and early winter. Lambing
occurs in spring, and newborns are able to keep pace with mom almost immediately.
Sparring for mating rights involves males ramming head first into each other at speeds of up to 20
miles per hour. Horns can weigh up to 30 pounds. The force generated is enough to kill a human. Ram
skulls are made of several plates, like human skulls, but the rams' do not fuse into a single solid piece
of bone. That design lets the plates shift to absorb the shock of the repeated blows. The curl of the
horns might also deflect some of the shock away from the head, while a large tendon connecting the
head and neck helps the head recoil.
Rams battling for a mate (Smithsonian)
This week's information comes from University of Michigan's Animal Diversity Web and
Indiana Public Media. Next week wraps up the energy series with a look at the elephant in the room,
nuclear.

Friday, July 3, 2020

Solar Energy

Solar power is another “clean” and renewable source that is emission-free and will never exhaust the sun. Not only do photovoltaic panels not drain the sun of energy, they do not diminish the capacity of other panels, so long as one panel is not placed on top of another.

There are two ways to use solar energy, active and passive use. Photovoltaic electricity (PV), solar heating and cooling, and concentrated solar are active systems. Passive solar building use design features capture and utilize solar radiation.

PV cells turn sunlight into electricity. This technology was accidentally discovered in 1954 when a scientist noticed that silicon created an electrical charge when exposed to sunlight. The solar powered calculator was born and eventually evolved into today’s solar panels. The early panels were made of silicon, but second generation panels use thin film and semiconductors. Thin film panels can be used as shingles, tiles, or façades and incorporate electrical generation into the design of a building. PV units can be found powering individual homes or on roadsides, collecting energy for lighting for highway signs.
How solar energy works (Sunpower)

Solar heating and cooling uses the sun’s radiant energy to heat or cool a building with the use of PV panels. A transpired collector is a black metal panel on the south-facing wall of a building that absorbs heat from sunlight. Holes in the panel allow heated air to pass through to the other side, where it is sucked into the ventilation system and throughout the building.

Solar process heating uses a solar collector (usually an evacuated tube or parabolic trough), a pump, a heat exchanger, and water tanks to heat a building. The evacuated tube is a series of glass tubes and reflectors that heat water inside. A parabolic trough is a U-shaped mirror focusing sunlight in a central tube. The focused sunlight heats water in the tube. The heated water is pumped throughout the building to warm it up. Solar cooling uses the same collection system, along with the magic of chemistry to cool the air.

Concentrated solar power is a generating system that reflects and focuses sunlight to create heat and steam that turns a turbine to create electricity. Because the system converts sunlight into thermal energy, it can be stored and generate electricity even on cloudy days or at night. Concentrated solar power can accompany a traditional fossil fuel plant as a carbon offset or as a stand-alone plant.
Solar array collection system (Colorado Springs Business Journal)

Passive solar uses site, climate, and material to use the sun’s radiant energy to heat and cool a building without the use of active mechanical systems like those mentioned above. Energy efficiency measures to reduce the required amount of heating and cooling is the first step. The second step is an unobstructed south face to maximize sun exposure. Sunlight entering the south facing windows is absorbed by thermal mass- material such as concrete, stone, or brick. The thermal mass absorbs heat from the sunlight during the winter and from warm air during the summer. Conduction, convection, and radiance are natural phenomena that circulate the heat throughout the building.

Like all other energy sources examined so far, solar energy is not completely “green”; it too has negative environmental impacts. Habitat loss for large solar arrays and concentrated solar plants can be mitigated by siting these in repurposed areas such as brownfields and reclaimed mine sites. Small scale units that power a single building typically have minimal impact, especially when roof-mounted.

Water use is a concern with concentrated solar plants. The sunniest areas in the US are often the driest, and water is scarce so a massive withdrawal of 600 to 650 gallons per megawatt hour of electricity can have a negative impact on desert denizens.

An additional concern is the hazardous materials used in the manufacture of PV cells. Many are used to polish the semiconductor surface and include hydrochloric acid and acetone. Petroleum is used in the manufacture of PV cells also, so even solar energy is somewhat dependent on fossil fuels. However, new technology that uses cotton and castor beans is being developed.

Thursday, March 12, 2020

Amazing Okavango

Ever hear of the Okavango River in Africa? You probably haven't. It's a rare river that flows into an inland delta rather than the ocean. During the winter, it floods the glassland and creates a seasonal wetland that attracts wildlife from all over Africa in one of the world's greatest migrations. It is an amazing oasis in the Kalahari Desert.
Flooded Okavango (Natural World Safaris)

The annual flood occurs at the height of Botswana's dry season, so it offers welcome relief to the plants and animals in the area, in addition to welcoming migratory animals of all shapes and sizes. The abundance of water boosts the growth of plants, drawing in herbivores. The herbivores attract large predators.
Elephants (Royist)
Safari cruise through the grasslands (National Geographic)

Among the many different animals who take advantage of the situation are elephants, lions, cheetahs, zebras, rhinos, 89 fish species, and 24 globally threatened birds. Not only is the Okavango key to survival of individual animals, it is crucial habitat for entire species.
Lion and buffalo (National Geographic)
A safari in the Okavango is like watching "The Lion King" live and in person. This weeks information comes from UNESCO World Heritage.

Thursday, April 4, 2019

Summer Vacation Guide

Spring just started, but it's not too early to start thinking about summer vacation. National parks have figured into vacation plans ever since the invention of national parks. They are great places to see amazing scenery- and crowds, or have a chance encounter with wildlife- and crowds. Here are a few lesser-known parks with fewer visitors. Just be careful getting there- some are very remote with little or no road access, which always makes for a better adventure.
By taking these roads less travelled, you'll get to experience more than the stereotypical majestic mountains and sweeping desert vistas. Our national parks have so much to offer!
Kobuk Valley National Park, Alaska
Great Kobuk Sand Dunes
Surrounded by mountains, this park is home to a vast caribou herd and extensive sand dunes. Yes, sand dunes North of the Arctic Circle! The sand is the result of glaciers grinding the mountains down. Also found in the park is the boreal treeline, where forest yields to tundra. Be prepared to fly in; there are no roads leading to Kobuk Valley and no services, either.
Tundra fire
National Park of American Samoa, American Samoa
Tutuila Rainforest
This is America's only national park south of the Equator. Full of white sandy beaches and coral reefs, it's a rare ecosystem in the park service holdings. The mountains and rainforests host fruit bats and several species of virds, including a beautiful blue kingfisher. Aside from natural splendor, you can also learn about traditional Samoan culture. Travelling there can be expensive, as American Samoa can only be reached by a long flight or a long ship voyage.
Pola Islands
Voyageurs National Park, Minnesota
North Woods winter
This northern Minnesota park is a kayaker's dream. About 40% of the park is water. This system of interconnected lakes, streams, and wetlands was named after the voyageurs, or four traders, who used this area to transport their wares from the interior to civilization on the Great Lakes. Today, the park preserves water quality, ancient rock formations, boreal and hardwood forests, and endangered species like wolves. While not as remote as Alaska and American Samoa, it's a long drive from the Twin Cities and getting around without a boat of some sort is limited.
Loons on a lake
Great Sand Dunes National Park, Colorado
Sand dunes with Sangre de Cristo Mountains
Off the beaten path in the Rockies, but not too far off, this park features alpine tundra, subalpine meadows, wetlands, forests, mountain streams, lakes, and of course sand. Such a diverse landscape attracts an equally diverse array of flora and fauna. Thousand year old trees share the park with prairie grasses, wildflowers, and scrub sage. Animal life ranges from dung beetles to horned toads to pronghorn, elk, and bear. There is only one road in, but it's an easy drive from Pueblo.
Elk with snowy sand
Wind Cave National Park, South Dakota
Cave boxwork
If you're looking for a good time above or below ground, Wind Cave is the place for you. Upstairs is a convergence of short and tall grass prairies and forest, right on the edge of the Black Hills. Downstairs is one of the world's longest cave systems. Sacred as the birthplace of the Sioux Indians in their origin stories, the cave gets its name from the wind blowing in or out of the small natural opening. Wind direction changes based on barometric pressure and is a good indicator of weather. While rare formations like boxwork can be found in the cave, rare animals like bison and black-footed ferrets are found above. This park is also easy to reach, about an hour south of Rapid City.
Prairie and forest
This week's information and all pictures comes from the National Park Service. Great Sand Dunes pictures come from their Flickr page.



Thursday, July 26, 2018

Desert Life


This time of year, there’s usually no place in America that’s hotter than the desert Southwest. The region is known for its striking red sandstone formations, deep canyons, and ancient ruins. While the desert may seem like a barren wasteland to the casual observer, it is full of life. If you know where to look. The critters of the desert have evolved with special adaptations that allow them to survive in a harsh environment. Let’s have a look at some.
Extreme heat and scarce water are two hardships of the desert. Because of the second problem, sweating is an impractical solution to the first problem. As a workaround, the jackrabbit has large ears which are full of blood vessels. The blood vessels bring warmer blood away from the body core to cool. The large surface area of the ears also helps the cooling process (National Geographic).
Black-tailed jack rabbit (NPS)

The kangaroo rat has adapted to life without beverages. It can go an extended period without water, absorbing what it needs from its plant-based diet. Too keep cool, it lives underground and is nocturnal (Arizona-Sonora Desert Museum).
Stephen's kangaroo rat (Arizona-Sonora Desert Museum)
The various cactus species have evolved to avoid water loss. All plants lose water through their leaves in a process called transpiration. Cactus plants minimize the loss by having long, thin needles in place of the leaves we’re familiar with on trees and other leafy plants. They also have an extensive root system for maximizing water collection potential and a wide, hollow stem for water storage (BBC).
Saguaro cactus (US Forest Service)
Other desert plants have adapted as well. Shrubs and non-woody flowers survive by growing deep roots that can reach down into the water table. They have hardy seeds that can last for years before germinating. When the rare shower falls, these plants simultaneously burst to life in a brief but spectacular desert bloom (Science News for Kids).
Superbloom (National Park Service)
The Great Basin spadefoot toad has a cool adaptation for surviving in the desert. They burrow underground and remain in a state of suspended animation for years until rainfall brings it to the surface for mating and feeding. Mating pairs will lay and fertilize eggs anywhere water collects, then the race is on for the eggs to hatch and tadpoles to develop before the water evaporates. The tadpoles are cannibalistic, which might be an incentive to hurry up and grow (The Nature Conservancy).
Great Basin spadefoot toad (Idaho Fish and Game)
You probably don’t think of shrimp living in the desert. The fairy shrimp’s habitat is ephemeral (seasonal) pools that form in depressions in rock. They are tough little buggers, able to withstand extreme heat. Their eggs can survive desiccation for decades, using sugars instead of water inside the egg. The eggs can remain in place until rain activates it and it hatches, or they can be carried on the wind to a new location and hatch there when rain comes (National Park Service).
Fairy shrimp (National Park Service)
Next time you happen to be in the desert, look around for these and other fascinating critters. The desert is alive, if you look hard enough to see the life all around you.