Environmental News

2 grandsons, one is 5 and the other 3, spend most of their day teaching me about dinosaurs. megalodon is one of their favorites.
spent the day at the exhibit at the museum of science. it is amazing to me how fascinated they are

 

Some cheery news with paddlefish being reintroduced into a Texas lake.
1,000 prehistoric fish released into East Texas Lake
An adult.

 

I don't think I'd trust anything that fish told me.

 

One of the other articles suggests that megalodons and great whites shared the top of the food chain. While the former may have been better able to eat the later, the later seems to have won the longer term survival battle.

But now it seems that great whites are no longer the top of the food chain, at least near South Africa. Some orcas (killer whales), or at least one pair of them, seem to have developed a fondness for great white shark liver, causing many great whites to look for different territory:

Orcas ripping great white sharks open off South Africa, says new study - CNN

 

depends on what roids he's on

 

I've always wondered about how to relate this to those of us doing long distance rides here, longer than any Tour stage. But being just a recreational rider, not any sort of race caliber athlete, haven't looked into what sort of real numbers I can produce.

That Tour stage is 103 miles long, with 15,580 feet of climb. Other stages (excluding shorter time trials and parade stages) are 80 to 137 miles. For comparison, major big rides here include RAMROD (Ride Around Mt. Rainier in One Day), 162 miles and almost 10,000 feet of climb, and STP (Seattle To Portland, 207 miles this year) but only ~5000 feet of climb (never more than 400 at once). I've not done the former, but many friends have. Most ordinary mortals enjoy the later over two days, but around 25% (a couple thousand riders) are masochistic enough to do it in one day. Including me, twice.

At least for the later, it is emphasized that the event is a Ride, not a race, so finish times are not recorded. (Many riders start early, or avoid the massive crowd by starting at home and pedaling to the nearest point on course, so official timekeeping would be futile.) From overheard talk, I believe the leaders are finishing somewhere in the range of 9:30 hours. I needed 15:10 at age 45, and 15:45 at age 58, with little daylight remaining. But a larger fraction of my day must be spent in rest stops, so the speed differential isn’t as large as the times initially suggest.

On that first ride, I was thrilled by a rolling average of 17 mph, while a younger coworker was disappointed to have fallen under 20 mph for the first time in his history (due to headwinds and less training).

My rolling times were about 12 and 12.5 hours, while I’m guessing leaders took a bit under 9. The climbing energy (for a given weight) is the same, but in the end most of that is transferred into wind drag on our (generally not too steep) descents. Figuring wind drag as proportional to the square of speed, I’m putting barely half as much energy into wind drag as the leaders, and am taking longer to do it. So if they are averaging 300 watts all day, then I must be averaging under 110 to 125 watts. Those ratios certainly sound much less impressive.

I hope to do this just once more (not this year), in my 60s, before getting too old. And hoping that point isn’t already passed.

 

The sample numbers there seem unreasonably high. As in, in my prime, I rode a decent distance at this speed (10 m/s, 22.4 mph), and am heavier, but there was no way I was putting out anywhere near this much 'best case' power, let along 'worst case':

"If we had instead used the best case numbers from above, we would have calculated a power usage of approximately 696 W = 0.17 kcal/s, a factor of 3 improvement in efficiency."

I stumbled across a biking calculator that gives numbers that seem more intuitively reasonable for the speeds I ride:
Bike Calculator

By this calculator, I was probably varying 150-200 W in the first quarter of the ride, dropping to 100-120 W in the last quarter, not accounting for the climbs. Well short of more serious riders, let alone racers. Speeds would be better if my back could tolerate the drop position all day, and with aerobars with brake levers (not shifters) on the ends.

 

After making several bike runs between LA county & San Diego County - switching from a Touring bike to a recumbent seems the best way to defeat drag (the lightning p-38). It took a bit of time to relearn the balance & quadricep muscle usage, but it ultimately shortened riding times. The thing is, the hardest battle to overcome was the fear of getting run over, being so close to the ground.

Recumbent Bikes WhyCycle? - The impartial cycling advice site.
And frankly, there's the vanity issue. Riding a recumbent makes one feel like a dork.

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it looks really awkward, and visibilty is definitely a problem. most have a flag flying, but still...

 

covid?

 

On human exploitation of wildlife...
IPBES Sustainable Use Assessment

This article is out today. referring to the report on Nature.
Major wildlife report struggles to tally humanity’s exploitation of species