Yosemite Hiking – Half Dome Hike Death Risk Calculation

Hurray !
My family and friends just survived a top ten dangerous hike in the most dangerous National Park in America! http://www.backpacker.com/october_08_americas_10_most_dangerous_hikes/destinations/12631

Half Dome Cables, Yosemite

Well, technically, Linda isn’t home yet …. but the odds are in her favor.  : )Of course our odds of survival were always very good, but Yosemite has been a dangerous park, especially last year 2011 when  18 people (!)   died there :  http://www.nytimes.com/2011/09/06/us/06yosemite.html?pagewanted=all

Spooky description of a 2007 fall off the cables:
Book about Yosemite deaths.
Base jump off the place where we took pix:  http://www.youtube.com/watch?v=WdxU2tDbL54

Of course you have to compare the small number of deaths on that hike over many, many years (20 on dome, 60 on trail) with the huge number of people who *survived* their hikes, as I think we did (assuming no parallel universes where we didn’t survive), to get a reasonable risk calculation.   You also need to compare that risk to other risky things we do, such as *drive to Yosemite*.I wanted to try a shot at calculating which is more dangerous – the drive to Yosemite from Oregon, or the most intense part of the hike up Half Dome – the cables.

Obviously there are many confounding variables.  Nobody was drunk driving, our hiking experience is higher than average, for simplicity I’m not using the entire hike death stats  (60 deaths but many millions more hikers on the entire 8.5 mile trail – this would give a *safer* number for sure, but would reflect hikers and deaths who never made it to or beyond Vernal falls).   So lots of confounders, but here’s my shot at a risk number:

Let’s assume that the  20 dome deaths are since cables were installed by The Sierra Club in 1919  (hey, THANKS Sierra Club!):
Now we need to estimate the number of people who have made it up there as we did.   Ranger guy below the dome and internet tells us it is now about “350-400 per day”.   That would be current high season with permit restrictions so hard to know the past until I can find more records.  But we know that the low season (winter) is about 0 per day.   Probably far fewer people in 1919 than now, so let’s *wildly guestimate* that on average, since 1919,  100 people per day go up, and that almost all that traffic is during the high season of June, July, August, September when cables are elevated with the metal rods  (in the past and in winter they lay flat on the surface).  100×120 days = 12,000 people up per year.  90 years of cables x 12,000 =  1.08 million ascents of half dome over 90 years.    ROUND THIS WILD GUESTIMATE to one million people up  half dome over all of human history.
We now have 1,000,000 people who went up and 999,980 people who come safely back down.  20 of the million, sadly, died on half dome.   Thankfully, every single one of us remains in the 999,980 group of happy Half Dome hikers.
Your chance of dying on the final half dome portion of the hike is, very very approximately, if our assumptions are reasonably accurate, about 20 / 1,000,000 or one in  50,000.    We could also state this in this fashion if our assumptions are correct:
“For every 50,000 people who go up the final portion of the half dome hike … one will probably die”.
For extra drama we might note that we had 6 people on the hike so the (pre-hike) odds that one of us would die were 6/50,000 or 1 / 8333.
Now we need to compare this to our 900 mile car trip home.   Car travel is one of the more dangerous things we do on a regular basis.   VERY ROUGHLY in California there are 1.21 deaths per 100 million miles travelled
We did not travel 100 million miles so we need this calculation to figure out deaths per Yosemite trip:
The chances of dying during 900 miles of car travel in California:  900 x  [1.21 / 100,000,000] =   .00001 deaths per Yosemite trip.
So, on average of all drivers and cars and circumstances, the chances that somebody will die on a trip of 900 miles in California are about one in 100,000.      Put another way this means that, very approximately:
” For every 100,000 people who take a 900 mile trip to Yosemite by car, one will die ”  
So if all these assumptions are pretty reasonable, than we can state that the half dome portion of the hike with its one in 50,000 chance of death, is about twice as dangerous as the car ride with its 1 in 100,000 chance of death.  


Tomorrow we’re off to hike in Yosemite National Park, one of my favorite places in the world. We’ll camp in Little Yosemite Valley and hike up Half Dome via the cables that make it a lot safer than … without them! It’s a really fun adventure with amazing views from the top of Half Dome, especially lying right over the edge and looking straight down into Yosemite valley below.

Yosemite NP

Half Dome, Yosemite National Park

Canyon Creek Lakes, Trinity Alps, Northern California


Above Lower Canyon Creek Lake looking South

Originally uploaded by JoeDuck.

We continued our labor day tradition of meeting our great friends in Weaverville, CA and then hiking in to the Trinity Alps Wilderness along the trail up to the Canyon Creek Lakes.    We camp about 4 miles in and then hike into the lakes the next day which is another 4 miles.    It’s a fantastic trip with the kind of scenery you find pretty much only in Northern California – sweeping mountain vistas, smooth granite outcrops and peaks, pristine mountain lakes, streams, and waterfalls.    Azure blues and deep greens and a star filled sky complete with the recent meteor shower.   It doesn’t get much better than that and the Trinity Alps are one of my favorite places in the whole world.

One really cool addition to the experience this year was looking at the hike through Google Earth, where by tilting the imagery you can really get a neat feel for the vistas along the actual hike.     We also found some photos of our first trip in to the Canyon Creek Lakes some 22 years ago. The scenery had not changed but … um … I think we have

Canyon Creek Contemplations

This morning I woke up along Canyon Creek in Trinity Alps Wilderness of Northern California. This is a great hike we’ve done several times, and I’ll get the pix up tomorrow. We had some fun conversations at camp and around the fire as several meteors streaked across the magnificent night sky:

I think Chem trail conspiracy notions are silly, but they came up:
Chem Trails – nice description of the issues

Star and Moon motion


Wow, and the $2000 EPA cleanup of broken flourescent bulb is really quite a story , and one very related to Mercury. In that story evil Fox news notes what appears to be a real environmental disconnect between advocacy for using compact flourescents and the dangers that will be caused by the ones that get broken and go to landfills. I remain confused about this. In fact I just broke one on the porch last week and had *no idea at all* about special cleanup needed, so I hope we all live.

Google Earth and Maps has some neat imagery of Canyon Creek Lakes area. If you don’t have Google earth it’s quite an amazing and free application to visualize cities and trails. Maps does not need download but Google Earth is a fanastic and free download.

Here’s the NYT article about life being a computer simulation

Here is Kurzweil’s AI site for updates on the singularity and conscious computing. It reads a bit sillier than it should based on his scientific and history “credentials” and the fact many AI folks think conscious computing is only 1-2 decades away.

Here’s my take on two neat AI projects

Chips and Human Neuron Salsa and this related item just in from Israel IMHO the intersection of human brains and computing will initiate the most profound societal transformation in history.

And then again, maybe it’ll just let us watch TV in our heads, which would be pretty cool too.

Global Warming – less hype, more science please.

Yahoo’s got a noble initiative going to “fight” climate change but as with most of these efforts I’m very skeptical this is where so much of the smart thinking, time, and money should go.

I wrote them:   With all due respect to the noble intentions I think I’d rather see Yahoo work on … profitability and web innovations. Warming is so *incredibly* expensive to try to fix it’s better to spend our treasure and time on the low hanging fruit problems of the world: microloans, malaria, aids prevention, etc, and focus on conservation and alternative energy. With China as the leading producing of CO2 I can’t help but think our many noble high tech solutions are just jousting at the energy windmill.

I’m not nearly as skeptical about human induced climate change as my friend Glenn,  but I share his concern about the alarmism and “groupthink” that is now pervasive in the Climate Change community.     Recent IPCC reports have been

My big concern remains that we can’t do much about this and therefore we should tackle the catastophic things we *can* easily fix.  Those are disease and poverty, water, etc.    Incredibly people seem to ignore these basic human health and poverty problems as “insurmountable” when in fact  they are relatively easy to solve with modest allocations of time and money, while people focus on problems like Global Warming and longstanding religious conflicts that likely have *no* realistic solutions for decades, centuries, or even millenia.   Also important is that feeding people and raising standards of health and living leads to much, much smaller populations (this “prosperity leads to lower population” effect is very well documented but I can’t believe how many people think that helping the poor leads to more poor people (the “feed and breed” ideas of Malthus).  This is a very dangerous and wrong assumption and not backed by any research with which I’m familiar).

I propose that well intentioned, rational folks should use a ‘triage’ system where we take major global problems and the cost of their proposed solutions and prioritize these actions on the basis of where we can do the most good for the least money.

But as my friend Linda pointed out wisely last year during our hike in the incomparable Trinity Alps, it’s possible that at least with warming people are inspired to act, and in general these actions are leading to more energy conservation and innovations.    Better *something* good than nothing good, but I’m still going to advocate for a rational, not emotional, approach to all this.

Rescue Wiki – check it out !

Rescue Wiki is a new website to assist Search and Rescue efforts around the world. Like DangerData.com it is an experimental approach to enlisting online help for SAR efforts.

Wikis can be a good way to collectively process information if you are dealing with a computer savvy crowd, but in my experience they limit participation compared to blogs which make it easier to comment and to passively participate.

Rescue Wiki has both, which may be a great solution. Check it out and let him know what you think!  Rescue Wiki

Kim Search discussion page 9

Oregon State Sheriff’s Association Report

(Feel free to discuss this report in the comment section below)

The discussion of the Kim Family Search in the Rogue River region of Southern Oregon continues in the comment section below. Please feel free to chime in.

For earlier comments and information links about the Kim Story click here or at the top of any page on the “Kim Story” tab.

Survival Tips and Survival Kits

Blogging the Kim Family Search story has led to a number of great comments and articles about survival kits and wilderness survival tips. Feel free to leave more in the comments section – just post the URL and it will link up automatically.

Wilderness Survival Tips Website

Field and Stream Pocket Survival Kit: This article shows how to build a very inexpensive but fairly complete and light survival kit.

Survival tips from the TV Series “Survivorman”

Google Search for “Wilderness Survival”


Supplies list for long road trips: