Carnival of the Arid #2

If you like reading about the desert, this is a compilation of recent desert-related blogs, including one of mine:
http://faultline.org/index.php/site/item/cota2

Desert Destination: Red Rock Canyon National Conservation Area

Every Monday we visit a desert destination.
Red Rock Canyon Conservation Area is located just 17 miles west of Las Vegas' downtown. The bright red sandstone rocks can be seen from most of the city, but they make up just a small part of this nearly 200,000-acre area managed by the Bureau of Land Management. 

There aren't a lot of signs showing the way to get to Red Rock, but fortunately there are just two main ways to go, and they make for a nice loop if you want to see some different landscapes. The northern way is to take Charleston Boulevard west, and it eventually turns into Highway 159. The southern way is to take Blue Diamond Road, Highway 160, and then take the cutoff to the north, Highway 159.

 
A fee booth is at the entrance of the 13-mile scenic drive. It's possible to visit parts of Red Rock directly from Highway 159 if you really don't want to pay the fee, but it's only $5 per vehicle, and you can also use the America the Beautiful Pass here. 

A good first stop is the visitor center. There is a lot of construction around the visitor center, as they expand the one made in 1982, which was made when 20,000 people visited Red Rock a year, to a new one that can accommodate the 1,000,000 annual visitors.

The visitor center is up above the parking lot, and it could use a few more signs. While waiting ten minutes in the parking lot, three different people asked where the visitor center was. Inside are a variety of exhibits, some good views, and friendly volunteers.

After the visitor center, it's time to head down the Scenic Drive. This is a one-way loop with a maximum speed limit of 35 mph, so you can just take your time and enjoy the scenery. The scenery is eye-popping, beginning with the Calico Hills.

This area is popular with rock climbers--can you see the two climbers and two belayers in the photo above? Red Rock has all different levels of climbing, from beginner to expert routes that take more than a day to complete.

The Calico area has some pullouts to stop and enjoy the view or start a hike. In the foreground of this photo is a burned Joshua tree. Numerous wildland fires have burned in Red Rock Canyon over the past years.

 
Looking in the other direction, the burned area goes as far as the eye can see. The land managers are concerned about non-native vegetation taking over. To combat that, rehabilitation efforts like seeding with native vegetation are ongoing. 

The Red Rock Canyon newspaper lists 19 different hikes. It was hard to choose which ones would be best for us. Because we had Desert Boy along, we decided the Children's Discovery Trail near Lost Creek would be a good place to start. The trail is 0.7 miles long and was listed as easy. 

At first, Desert Boy was bored with how easy the trail was.

Then we got to the wash, which during flash floods can quickly fill with water. The wooden structure and the pipe on the left-hand side are a crest-staff gage. Inside the metal pipe is a piece of wood and some cork. When the flood comes through, the water makes the cork float and it sticks to the wood. A USGS employee checks it after the flood and can estimate the amount of water based on the height of the water, the slope of the wash, and the substrate. USGS records show that this gage was in operation from 1961-1999 and the highest recorded flood was over 7,000 cubic feet per second, in 1969. To put this into perspective, 7,000 cfs is about the average streamflow for the Columbia River, that giant river flowing from between the states of Oregon and Washington into the Pacific Ocean. Seven thousand cfs is more than what usually flows in the Hudson, Chicago, and Rio Grande rivers.

Desert Boy was more interested in picking up rocks, and his great-uncle had fun photographing him.

Then the trail got a little rockier and steeper. Did Desert Boy want to be carried? No way! He likes challenges, and fortunately the knees in his pants were up to it. He walked/crawled/rolled down the entire trail by himself. 

After our hike, we continued along the Scenic Drive, passing more beautiful scenery. Then we reached another trailhead, for Pine Creek Canyon.

The Pine Creek Canyon trail descends from the parking lot across a rather flat area full of a variety of bushes and grasses. In the distance is the triangular-shaped rock formation called Mescalito. From a guidebook I knew that the trail led to the canyons on either side of Mescalito, and it sounded like a fun place to go rockhopping.

Eventually we got to a wilderness boundary sign. There are two wilderness areas in Red Rock Canyon NCA: Rainbow and La Madre, designated in 2002.

Mescalito appeared closer as we walked down the narrow path with the red dirt.

Desert Boy ran out of steam (and so did his mama carrying him in the backpack), so the great-uncles stepped in to help him through the tall bushes...

...and across the rocks down into the streambed.

The streambed was very rocky and had quite a bit of vegetation growing in it, making it difficult to travel. The trail had split in many different directions, and we couldn't figure out which one was the right one. So instead of trampling vegetation, we decided it was time for us to head back to the car, and we turned around.

On the way back, Desert Boy found a nice place to rest. Hiking in February was really comfortable, although we noticed a big change in temperature from sunny to shady areas. During the summer heat, this hike wouldn't be nearly so nice.

This big yucca graced the trail on the last stretch up to the car. It was a pleasant hike, although we had been expecting the trail to lead us somewhere instead of petering out. Nevertheless, it was a welcome breath of fresh air and quiet not far from Vegas.

Red Rocks has lots of territory to explore, and I hope to be back soon to check out some more trails.

Windmills in the Desert

Out on the desert floor I see a windmill, looking lonely out in the desolate brush. The windmill is a sign of early technological progress--a way to harness the wind to pump water from the ground and provide for livestock, irrigation, or other water needs. The windmill is an indication of a rural area, a place without electrical lines.

Over the last 120 years, the basic design of a windmill hasn't changed much. The fan (or wheel) at the top of the tower is turned by the wind. This rotary motion turns a set of mechanical gears that raises and lowers the "sucker rod," the rod that extends below the fan and down into the ground. The up and down movement of the rod (reciprocating motion) powers the cylinder pump located underground.

This cylinder pump is near the bottom of the well, which is dug or drilled into an aquifer. Perforations in the well casing allow water to percolate into the well, and then the pump keeps adding water to the bottom of the pipe, creating enough pressure that the water is forced upwards and out of the pipe. 

For this windmill, once the water reached the surface, it was put into this livestock tank. Today it's full of tumbleweeds, and none of the similar windmills in the valley are working. It's been quite a few years, even decades, since the last one pumped water to the surface. My husband says he can remember one working windmill as a child. 

So why aren't more of these windmills, with their simple technology, in use? With the arrival of electricity, brought by the Rural Electrification Association from the 1930s to 1950s, windmills all over rural areas went into decline because it became easier to pump water with a motor that had a steady power supply. Nowadays, with increased energy prices, more people are repairing, restoring, and installing windmills, and learning how to maintain them. 

This windmill is an Aermotor, made in Chicago. Aermotor windmills were first sold in 1888, and were made in Chicago until 1958. Today they are still sold, made in San Angelo, Texas. 

I had a little fun with lighting effects. The windmill is a fun subject to photograph.

The old timers were on to something, harnessing the free power of the wind to make life easier for them. Nowadays, more and more people are turning to the wind again, not so much to lift water from the ground, but to create electricity. The windmills that are used for electricity are called wind turbines, and we are starting to see more and more of those out in the desert.

Plant Survival Strategies in the Desert

It's been dry out here for a long stretch, and whenever that happens I can't help but marvel at the interesting ways plants have evolved to live in such a dry climate. 

Prickly pear-Opuntia sp.

Xerophytes are plants that have changed their physical characteristics to withstand long periods of dryness. One classic example is a cactus. Instead of having leaves, which have a big surface area and thus lose a lot of moisture to evapotranspiration, a cactus has spines. The stem (cactus pad) is green and contains chlorophyll, acting as leaves do in other plants. However, this stem is often covered with a waxy coating which prevents water from leaving. In fact, many cacti can store water within their stems. They also have shallow, spreading root systems to absorb any available moisture from a brief rainstorm. 

Gray rabbitbrush-Chrysothamnus nauseosus

Another adaptation of plants that live in the desert is very small leaves, so there is less surface area for water to escape. Some plants' leaves have the ability to close their pores (stomata) to keep water in them under the intense sunlight, and some have fewer stomata than similar species found in wetter conditions. The plants may be very hairy to reflect sunlight and reduce the amount of air movement next to the leaves, which will wick away the moisture.

Stonecrop-Sedum lanceolata

Succulent plants, like stonecrop, can store water in the vacuoles, which are specialized tissues in their cells. All cacti are also succulents, and barrel cacti are famous for being able to contain large amounts of water. Many desert plants can also store water in their roots.

Joshua tree-Yucca brevifolia

The metabolism of desert plants is often very slow to reduce energy requirements. A Joshua tree only grows about two feet tall in ten years. A Saguaro cactus takes 30 years to grow just a few feet tall.

If you've looked out over a scene of desert plants, it may have seemed sparse. The plants do not live close together on purpose--there are so few nutrients and so little moisture that it takes quite a bit of space for each plant to obtain them. Spreading root systems help keep others away. In addition, some plants, like the creosote bush, have roots that are poisonous to other plants so that it's not crowded and has plenty of room to get the moisture and nutrients it needs.

Fourwing  saltbush-Atriplex canescens

Most plants need photosynthesis to live. Common photosynthesis uses what's called the C3 cycle, in which the plant fixes carbon into a three carbon compound (phosphoglyceric acid) in order to make carbohydrates. But that's not the only way photosynthesis can occur. Some desert plants like those in the goosefoot family (like the fourwing saltbush above) and bunchgrasses use the C4 cycle, which creates a four carbon compound (aspartate or malate acid). This process is more efficient in maximizing energy.

There is yet another method of photosynthesis, called Crassulacean Acid Metabolism (CAM). It is used by succulents and is even more efficient. These plants open their stomates at night to absorb carbon dioxide, and then during the day use it for photosynthesis. With the stomates open only at night, they use only one-tenth the amount of water as some plants.

Greasewood-Sarcobatus vermiculatus

Other desert plants have developed long root systems to tap into underground water. These phreatophytes are good indicators of a relatively shallow aquifer system--something important for desert travelers to learn to identify. Mesquite trees can have roots that go down 80 feet, while greasewood roots may grow 50 feet to reach water. Many of these phreatophytes, like the creosote bush, will also have some roots close to the surface to capture rainfall. 

Ocotillo-Fouquieria splendens (BLM photo)

Another adaptation to desert dryness is to go dormant when not enough water is available. The ocotillo is a classic example. After rain, it will grow leaves and flower. As the climate dries, the leaves will fall off, and the ocotillo will go dormant again. It may repeat this cycle five times in one year! Greasewood also will lose leaves if its deep root loses contact with the aquifer. It may appear that the plant is dead, but once enough water is present, the leaves will come back (unless it has been dry too long!).

Indian Paintbrush-Castilleja sp.

Annuals like Indian paintbrush will only bloom when their seeds have had the right moisture and temperature. Sometimes the seeds will lie dormant for years and years until the right conditions are met. Then the plant will produce spectacular flowers. In a few days or weeks, the seeds are scattered and await the next set of climate conditions that will allow them to show their beauty again. The drier the conditions, the more annual plants that live there. It's estimated that half the plants in the Sonoran Desert are annuals, while even drier climates may consist of 90% annuals.

Tufted evening primrose-Oenothera caespitosa

Pollination can be a challenge for some desert plants, because not many animals are active in the extreme heat of the day. One adaptation is to flower at night, when more potential pollinators are active during the cooler conditions. 

Another adaptation of desert plants is to go to the water. Plants around springs and streams are extremely different than those just a few meters away, where conditions are much drier. Changes to that water source will reduce the diversity of the plant communities.

As you can see, plants have developed a large number of ways to survive in the desert. Some have developed unique ways to store and gather water (succulents). Others have learned to tolerate drought conditions by going dormant. And some plants avoid drought by staying in the seed stage until the conditions are just right for a short burst of life. Because of these adaptations, desert plants are often easy to recognize. They have to deal with extreme conditions, and in doing so, they have become interesting plants with recognizable characteristics. Although the desert may seem a harsh and inhospitable place, indigenous plants have learned to live--and thrive--with the dry conditions.

The Extraterrestrial Highway

I saw this lovely cow crossing the ranch road the other day. Now, for most people, this would not be a memorable moment. But there was something in the cow's stature, the far-off mountains, and the winter lighting that made me remember of a trip I took a few years ago, a trip not to be forgotten.

That trip was out to a desolate highway, with plenty of open range, except the open range wasn't quite the same as it is throughout the rest of the West. This open range had the special designation shown above the cow on the sign. (Photo from rachel-nevada.com website). I kept expecting to see cows being beamed up, and the music from Close Encounters of the Third Kind played in my head.

This trip was out on the Extraterrestrial Highway, Nevada 375. This 98-mile long highway only passes one town, Rachel, NV. Calling it a town is a bit of a stretch, with just a scattering of buildings. Normally it would be totally ignored, but it has the fortune of being close to the infamous Area 51. If you like UFOs and aliens, this is a mecca. 

The Little A'Le'Inn is a restaurant and hotel. When I went in, some folks from the military base were enjoying a little time off by entertaining themselves with looking at the numerous photos covering the walls of UFOs and clippings of strange sights seen in the area. Locals offer tours to special spots where outsiders can peek into the ultra-high security area and try to determine what's happening inside. (By the way--the magnet above is a bit old--the new area code is 775, but the rest of the phone and fax numbers are correct.)

At the time I took my trip, the Nevada tourism office was offering a promotion that if I turned in a couple receipts from the ET highway, I could get this cool bumper sticker. I still haven't ever seen anyone else with one. I wonder why not??

And after recalling that wonderful trip and all the potentially strange things happening over the Great Basin desert, I look closer at the image of the cow crossing the road. Maybe some of those white clouds really aren't clouds after all...

Cosmic Ray Center, Millard County, Utah

Out in the isolated West Desert of Utah a strange sight may cause drivers along US Highway 6 & 50 to take a second look. Is that a tanning bed out in the sagebrush?  And another? And another, each spaced out in lines that cross the highway?

These strange apparatuses are part of a study being conducted west of Delta, Utah, to measure cosmic rays. Educational institutions from Japan, Korea, Russia, China, Taiwan, and the United States are involved. The headquarters is in Delta, and that's where the data is also processed.

The study is "to observe cosmic-ray-induced air showers at extremely high energies using a combination of ground array and air-fluorescence techniques." Okay, what does that mean? It probably makes perfect sense to my brother, the physicist, but for those of us who are not immersed in physics, it may be a little nebulous.

First off, what are cosmic rays? Here's the simplistic answer: tiny stuff you can't see with the naked eye that comes from outer space. Now here's the official answer: The term "Cosmic Rays" refers to elementary particles, nuclei, and electro-magnetic radiation of extra-terrestrial origin. These may include exotic, short-lived particles such as muons, pi-mesons or lambda baryons. (okay--did any of you have fun saying "muons"? I started imagining cows flying through space. Sorry for this tangent, but I couldn't help myself. Moo.)

Cosmic rays weren't discovered until the 1930s, when Austrian physicist Victor F. Hess went up in a hot air balloon over 17,000 feet high, measuring radiation along the way. He was surprised to find that the radiation increased with altitude, and surmised that radiation was entering the earth's atmosphere from outer space. He called this phenomenon "cosmic radiation," and later it was coined "cosmic rays." For his trouble, he earned a Nobel prize in 1936.

Next, what is a ground array technique? The ground array uses 576 scintillation detectors. Here's what one looks like:

And from its better side:
These scintillation detectors are laid out in a grid, each 1.2 km away from the next. The research area covers 760 square kilometers. Helicopters were used to install them, with each one weighing about 250 kg. 

The map below shows the ground array of scintillation detectors.

On the sides of the grid are fluorescence detectors. Sorry, I haven't made it to any of them to photograph yet, but researching this study has piqued my interest and I may have to wrangle an invitation. The fluorescence detectors are able to detect cosmic rays with much less energy (between 3x10^16 eV and 10^19 eV to be exact) than those detected by the scintillation detectors (which only detect cosmic rays greater than 10^19 eV).

Let's get back to the tanning beds--oh, I mean scintillator detectors. They are double layer scintillators which sample the charge particle density of the air shower footprint when it reaches the earth's surface. Okay, I took that last sentence directly from the project website. I think that means when the cosmic rays get close to earth, these detectors see how close together they are. (Please correct me if I'm wrong!)

The solar panel on the scintillator detector collects enough energy to power it for an entire week in complete darkness. Unless Yellowstone explodes and we're shrouded in really thick ash blocking out the sun, we probably don't have to worry about that. 

The magazine Science took note of this huge project, called the Telescope Array. It came about when two rival groups merged, using their two different techniques in this one project. Despite its name, no telescopes are part of the project; they had been included in an earlier proposal. Japan put up $13 million of the $16 needed to install and operate the project, but it was never planned to be installed in Japan because of the increased humidity there. 

One of the reasons to study cosmic rays is that physicists had been noting more higher energy cosmic rays than expected. Some can hit the ground with the force equivalent of a golf ball hitting the fairway. It makes me want to duck under one of those thick scintillation detectors so I can avoid getting hit.

This post just scratches the surface of this interesting project, which includes lots more acronyms (like TALE) and terms (such as "energy spectrum"). To learn more about this project, visit the Telescope Array website. And if you happen to be driving near the project area, you might  think about particles falling from outer space all around you. Someday we might understand what's out there.