WHY ARE PLANETS ROUND?

      Since space is a vacuum, there should be no resistance, and therefore no friction to cause the rounding.

      True, but friction doesn’t shape the planets. Rather, it’s gravity that dictates their spherical shape. A planet has so much matter that its total gravitational force acts as though it emanates from the center, pulling the outside particles toward the massive core. And when everything on the outside is being pulled inward with identical force, a sphere is the only possible shape it can assume. Furthermore, the more massive the planet, the stronger its force of gravity. On really big planets the force is so strong that tall mountains would be flattened. But on smaller planets the force isn’t as great, so very strong structures wouldn’t crumble. Knowing that, you can bet that alpinists of the future will have their sights set on smaller planets like Mars, where the volcano Olympus Mons rises over 70,000 feet, more than two times the height of Mount Everest.

HIKE OF THE MONTH

      Summer isn’t far off, so it’s time to begin planning hikes to get in shape for your long term. This month’s hike takes us to Sequoia National Park in the Sierra Nevada Mountains. It’s a great 3 day weekend hike for a long term conditioner. And it qualifies for an E peak on the Peakbagger List.

      With all the snow we’ve had this year, better check on snow levels before venturing to the high country.

      The Lodgepole and Mt Silliman  7½ minute topographic maps are used for this hike to:

MT SILLIMAN

      The trail is called the Twin Lakes Trail which starts essentially at the Lodgepole campground just beyond Lodgepole Village. To reach the trailhead from Los Angeles, take the 5 freeway to route 99 just beyond the Grapevine. Follow route 99 through Bakersfield to route 198. Go east through Visalia and continue through Three Rivers and Giant Forest to Lodgepole Village. This is a 5 to 6 hour drive. Pick up a permit at the Ranger Station.

      From the trailhead at 6800 feet elevation, follow the Twin Lakes trail north as it parallels Silliman Creek. After two and a half miles, the trail turns abruptly west to cross Silliman Creek at 7440 feet elevation. Instead of crossing here, leave the trail and head northeast up the canyon on a rather faint use trail. You will be paralleling Silliman Creek and will reach Silliman Meadow about a mile beyond the turnoff point. Continue less than a mile where you will reach a steep rock slab. At the base of the slab, about 8600 or 8700 feet elevation, you will find shelter and a good place to camp. The stream is nearby. The hike from the trailhead to this spot is about 4 miles, gains about 2000 feet elevation and will take about 3 hours (about 4 hours according to the backpacker’s rule). 

      Proceed west up the slab being cautious with foot placement as it is steep. Some of your hikers may need instruction on climbing a friction slab, finding the shallow depressions to step in and keeping the weight directly over the feet to maximize friction on the slope. Eventually you get to the top of the slab and it levels out somewhat.. You continue west, passing to the north of Silliman Lake, then to the south of a second lake shown on the topo. Just beyond the second lake, Mt Silliman is in view and you head north to the east of the peak. When you gain the ridge, follow it to the peak for a fantastic view. Retrace your steps back to the camp spot. The round trip is about 4 miles, gains about 2600 feet and will take roughly five and a half hours, about twice the time calculated by Naismith’s Rule because it is cross country with some rock scrambling and progress both up and down the slab is slow going.

      The trip back to the trailhead from the camp spot takes about two hours.

      One way to do this hike is to drive to Lodgepole on Friday and camp in the campground there if you are lucky enough to find an empty campsite. An early start on Saturday will make it possible to backpack to the camp spot and then dayhike to the peak and back, camp, then hike out and drive home on Sunday.

      An alternative and perhaps better hike plan is to start driving early Friday and hiking to the camp spot. This has the advantage of not needing a site in the campground but makes a long day and no time to acclimatize to the altitude. You then have all day Saturday to start late, enjoy the climb and return to your already established campsite.

      Other groups have stayed on the Twin Lakes trail to the lakes, camped there and climbed the peak from the north. This adds a lot of distance to the hike.

GLOBAL WARMING/ICE AGE

      Everyone these days seems concerned about global warming. But we know that ice ages have occurred in the past, so when will global warming stop and the next ice age occur?

      Relax. Glaciers aren’t expected to swallow up major real estate on the continents for another 80,000 years. Over the last 2.5 million years or so, ice ages have returned, fairly consistently, every 100,000 years. They are caused by subtle changes in the earth’s orbit and its distance from the sun, factors that decrease the amount of sunlight striking the planet, which allows the ice to creep south. But that’s not the whole story, according to David Anderson, NOAA paleoclimatologist. An ice age also requires “feedbacks” which amplify the cooling. One prime example: the albedo effect, whereby ice reflects sunlight, causing more cooling, which makes for bigger glaciers. Other variables play a part, like the amount of carbon-dioxide-consuming plankton on the ocean surface. Since we humans are in the process of increasing CO2 amounts, you might wonder whether global warming will ever make ice ages a thing of the past.

Well, none of us are going to live long enough to find out.

ALTITUDE AFFECTS APPETITE

      What happens to appetite up high? Well, it disappears into thin air. Researchers are largely stumped as to why, but they know that hypoxia, or oxygen deprivation,  can cause drastic bodily changes. On the appetite front, scientists are focusing on three hormones that regulate hunger – gelanin, neuropeptideY and leptin. Leptin seems to be especially crucial: As you climb above 9,000 feet, your fat cells start overproducing it, which tells the hypothalamus that you’re full. Careful acclimatization may ameliorate the problem, but that takes time. And since there are no drugs – save cannabis – proven to stimulate appetite, you’ve simply got to force those nibbles. Even if it seems impossible, stresses altitude specialist Dr Peter Hackett, you need to choke down something in small portions, the more calories, the better: energy gels, sweets, pastas dripping with chutney. If you don’t, you’ll start burning muscle and that can be catastrophic.

TREES HELP US SURVIVE

      So how many trees does it take to supply enough oxygen for one person to survive?

      First, you need to figure out how much oxygen one person consumes. Southern Oregon University biology professor John Roden estimates that the average human requires about 130,000 liters per year. Trees both produce and consume oxygen, but in a productive tropical rainforest, the average tree releases 273,000 liters of oxygen per year. At the other extreme, a desert juniper produces only 6,000 liters or so. So you’d need 21 junipers to keep one human aerated, while a single rainforest specimen produces enough oxygen for two. Next time you see a tree, take a deep breath and say thanks.  

LAYERING LESSONS

      Here are some trail tested tips for getting the most out of your clothing system.

l Plan ahead. Add and remove layers preemptively so your body temperature doesn’t fluctuate wildly. Put on that wind jacket before reaching a gusty pass or before getting chilled on a long downhill stretch. Strip to a base layer at the beginning of a long uphill. You’ll be warm soon enough.

l Pile it on. In cold weather, take precautions against the chilly transition from high-exertion hiking to no-exertion camping. If you’re drenched and chilling rapidly, put on a dry base layer, then every stitch of clothing you have. Overdo it. The pile-it-on plan keeps away shivers, which can be hard to recover from if your body lacks energy reserves for reheating.

l Keep your shirt on. At windy rest breaks, pull your fleece on over your windshirt. You’ll lose more heat if you take the windshirt off, put the fleece on, put the windshirt back on and so on. You’ll save time, too, when you’re ready to move again.

l Don’t over-shell. In arid climates (like the southwest), you can often get away with using one of the latest windshells as your only outer layer. The wind-blocking, water-resistant layers are all that’s needed for shedding light rain and snow. If you get a surprise downpour, wrap up in your tent fly or find an overhang to wait it out.

l Wear it dry. Thirty minutes before reaching camp, slow your hiking speed so that you stay warm without sweating. Your body heat will dry out base layers as you walk. It’s better than drying damp clothes in your sleeping bag at night.

l Layer your layers. If a synthetic shirt is still damp (and you’re not chilled) after you’ve made camp, wear it over a dry base layer and under warm, breathable outer layers. You’ll dry the garment and stay more comfortable than if you keep it next to your skin. Don’t try to wear-dry several damp layers at once. They’ll dry faster one at a time.

CANISTER CRAMMING TIPS

      Hard plastic or metal food canisters are the best tools for keeping bears out of your food. The most commonly used canisters (i.e., Garcia) hold about a week’s worth of food and scented toiletries for one person – if you pack carefully. Some hints:

w Pack your canister at home to avoid surprises at the trailhead.

w Remove packaging and place food in resealable plastic bags.

w Think compact, compressible and high calorie: tortillas instead of bagels.

w Pack in reverse order, so the last day’s food goes in first.

w Except in grizzly country, carry your first lunch and dinner outside of your canister.

w Fit flat, round foods like pita bread on the bottom of the canister, then press the food down as you add layers.

w Fill in gaps with bags of rice, dried fruit, hot chocolate and trail mix.

MEMORY LANE

HEAT RELATED ILLNESSES

      When the temperature outside rises, your body temperature rises along with it. When this happens, the brain sends signals or initiates heat control mechanisms to deal with excess heat.

      Increased blood flow is one of those mechanisms. Cooling occurs when the heart pumps more blood to vessels in the skin surface. This process causes excess heat to dissipate through, conduction, convection and radiation.

      If increased blood flow doesn’t control heat build-up, the brain sends a signal to the sweat glands, which are also located on the outer layer of skin, to start producing perspiration. The skin is then cooled by evaporation.

      Through conduction, convection, radiation and evaporation, skin can shed a lot of excess heat. But if the air temperature is at or above skin temperature, humidity is high or air velocity is low, the body’s natural cooling mechanisms become less effective. When this occurs, the heart sends more blood to active muscles and the brain.

      Heat rash, also known as prickly heat, occurs mostly in hot, humid environments where sweat isn’t evaporated from the skin. Sweat glands become plugged and inflamed and a rash occurs.

      If heat rash becomes severe, infection could result. To prevent heat rash, keep the skin as dry as possible and wear fast drying clothing. Cotton is a good choice.

      Heat syncope or fainting usually affects people who are not used to hot environments. It can also affect those who stand or sit for a long time. The increased blood flow to the skin -- one of the cooling mechanisms --  combined with inactivity may cause blood to pool in the lower body. This reduces blood flow to the brain and may result in fainting.

      Although recovery is often prompt, fainting causes falls and falls cause injuries. Once recovered, the person should lie flat and rest in a cool place. A doctor should be consulted.

      Heat cramps are painful muscle spasms that can happen after or during physical activity in hot and humid weather. Vigorous activity causes a lot of sweating. The loss of body fluids and body salts upsets the body’s delicate chemical balance, causing cramps.

      Treating heat cramps involves drinking plenty of water and massaging the affected muscles. Lightly salted water, (1/8 teaspoon per 12 ounce glass or one teaspoon per 4 quarts) and electrolyte replacement drinks also can be taken when you are sweating heavily.

      Heat exhaustion is caused by loss of body fluids and salt from sweating and decreased blood flow to the brain and other organs. Although oral temperature may be around 98.6 degrees, the heat control mechanisms are in trouble. Symptoms are excessive sweating, pale clammy skin, extreme fatigue, weakness, nausea, headache or dizziness.

      To treat heat exhaustion, move the victim to a cool place, and, if the victim is conscious, provide him or her with fluids. Be sure the victim rests with feet slightly elevated. If the victim is unconscious, an open airway should be maintained and CPR administered.

SUN PROTECTION

      According to the Skin Cancer Foundation in New York City, one out of every hundred children will, as an adult, develop skin cancer directly related to childhood sun exposure. A single severe sunburn in one’s first 10 to 20 years can double the risk of malignant melanoma, the most deadly and aggressive form of skin cancer. In addition, experts now say that children – especially those with fair skin, are not only more vulnerable than adults to intense exposure but also more time in the sun.

      In response, the makers of sun protection preparations are targeting a new, very young customer. The products have names like Baby Faces and Tender Places and Water Babies and smell more like baby lotion than coconut oil. And their SPF (Sun Protection Factor) designations are among the highest on the market.

      Although they offer the same protection as many products for adults, these new formulas are hypo-allergenic and are designed to be painless (the high concentration of sunscreen in products with SPFs above 15 sometimes sting skin). Children up to 18 years old should routinely use sunscreen with SPF 15 or higher.

      Skin cancer is becoming an epidemic. Kids should reach for the sunscreen every morning, just like brushing their teeth.

      Children who regularly use an SPF15 product during their first 18 years reduce their chances of developing skin cancer by 78% and reduce their chance of sunburn as well as retarding skin aging.

      Many parents fail to protect their children from the sun because they themselves do not understand the dangers involved. In fact, many are convinced that sun exposure is good for children.

      Some of the dangerous myths that people believe:

      wThat children need strong doses of sunlight. The fact: Sunlight helps make vitamin D in the skin; however, most scientists agree that alternate sources of vitamin D in fortified foods, such as dairy products, are just as effective as the sun.

      wThat a tan makes a healthy child. The fact: A tan is really a sign of injury. By the time a tan develops, permanent damage – which may eventually appear as wrinkles, blotches, sagging tissue and skin cancer – has already been done. So the term ‘healthy skin’ is a contradiction.

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Thunderstorms produce a jet of downdraft. When dry air is below a thunderstorm or when dry air enters a (In TrailHd 174 m we will discuss more about thunderstorms: hail and lightning.