Hacker Newsnew | past | comments | ask | show | jobs | submit | thenobsta's commentslogin

There's a bunch of other interesting flight path optimization work going on at https://contrails.org/.

It turns out contrails contribute to 2% of global warming power and is relatively easily avoided. The cost might be a bit more fuel consumption though.


The fuel consumption feels like the bigger problem since contrails last for hours vs co2 that lasts damn near forever.

They are roughly equal problems at the moment.

> Recent estimates show that contrails cause about the same amount of warming each year as all the CO₂ emitted by all flights from 1940 to 2018.


If we're measuring in terms of difficulty, CO2 is a much bigger problem than contrails.

Yes, contrails appears to be mostly solvable at a small cost in time and fuel and people have started to take action on that.

For most flights today though, if you only count the CO2 produced you're understanding the climate damage by about half.


It's one way to look at it I guess. CO2 is still the half of the damage that's way harder to fix.

Which is why work on fixing contrails is so important, it’d be insane to leave 50% improvement at a tiny cost unresolved whilst clawing back small percentage efficiency gains in co2 release from incremental and hideously expensive engine improvements.

We need to do both of course, but contrails should’ve been resolved the moment they were identified as so significant, it’s frustrating how slowly the industry responds to such an enormous opportunity (“we halved our climate impact last year” would be easy marketing)


As long as win there doesn't get used as an excuse to procrastinate on reducing co2. If you asked me I would favor a ban on all non-emergency flying which solves both problems.

Fun fact, contrails contribute to global warming, but only at night.

During the day they have a cooling effect by reflecting/blocking some light.

The optimal is not to eliminate them entirely, but to create them only early in the day so that they dissipate by sunset.


https://www.transportenvironment.org/te-asia-pacific/topics/... acknowledges the difference between day and night but claims that the sum of the effects still results in net warming during the day.

I don't see the claim you describe. That page discusses that daytime contrails have warming and cooling effects, but doesn't appear to take any stance regarding which effect is larger during the daytime.

Other sources claim that daytime contrails have a net cooling effect:

https://acp.copernicus.org/articles/24/6071/2024/

https://www.newscientist.com/article/2449212-jet-contrails-m...

https://www.carbon-direct.com/insights/contrails-major-clima...

The daytime cooling effect is much smaller than the nighttime warming effect, a total elimination of contrails would be a big improvement, just not as optimal as possible.


This is incredible. I have a Jetson lying around and will try to it out on this. I use it to play with vision models, not LLMs, and have been wanting a better way to manage the machine.


you probably want this if you have a jetson vs this spark repo:

https://github.com/anduril/jetpack-nixos


I loved reading the writing-setup guidance. After a lot of writing myself (mostly throwaway stuff) I've settled on a fountain pen with a small stack of decent printer paper on top a stainless steel clipboard. I skip the clip and use four magnets on corners of the paper to hold it in place. The magnets are either small enough or slide around easily enough to give me the space I need to write but hold enough to keep the paper in place. Importantly, the magnets don't cause any ripples or rising of the paper as the clip does over it's backing. Writing on this setup feels uniformly smooth.

Once I settled on this method, other writing setups felt unsatisfying. Maybe others will enjoy this setup as much as I do :)


I loooove the idea of teaching children inspiration instead of intimidation. Everything in the built world was made by a person just like you and me. That person may have had special training or unique experiences, but we too can move towards training and experiences and build/do cool things.

One of the ways I try to do this with my kid, is to try to investigate what's behind what we see and interact with -- with technical stuff it's asking how it works and how things fit together, with social stuff it's asking what's going behind the scenes and getting involved with it. Then reflecting on how cool the technical thing or event/social machinery is and what function it serves. This has been generative of tons of great questions from my kid and great discussion with them.


I would looove to see an analysis of this.


I can only share my empirical anecdata - I deal with code in different languages daily. Lisps have little difference when using with LLM just like any other compile&run language. But when you hook them up to a live Lisp REPL (which I admit requires some work) - it all gets very interesting.


This spurred me look at the board of Apple. Not a lot of builders/software/hardware/product people one there.


Megatron is also a film buff and the enemy of Optimus Prime. Optimus Prime flies well above the mezzanine.


I really like brown noise at night.

My immediate thought about this article was that I'd love to see this study on brown noise (albeit, with more participants).

Second thought was that, I wonder if some A/B testing with my garmin watch would give signal on this. Life is probably too hectic to get real signal.


Dr Seth Horowitz did some interesting work in psychoacoustics and documented how low amplitude low pitch movement-based sound(s) promotes falling asleep mediated by the vestibular system. Explains why its so easy to fall asleep in the car


Same. I'm very happy with my FW13 too. It replaces the MBA for my purposes -- dev on linux (mostly webdev on this machine, have a remote machine for gpu/heavy work), web browsing, streaming, some very light gaming (portal 2 on steam).

I'm waiting on that test too :) a few more cpu generations and I'll be itching to upgrade. I'm excited to for that to happen.


I wonder how these compare to high frequency training standards. It seems like they'd have similar speed/reliability/predictability requirements in the critical paths.


JFS-CPP bans exceptions because you would lose control over the execution of the problem. The HFT crowds didn't like it because you'd add 10ns to a function call.

At least before we had zero-cost exceptions. These days, I suspect the HFT crowd is back to counting microseconds or milliseconds as trades are being done smarter, not faster.


There are at least some HFT players who actually use exceptions to avoid branches on the infrequent-but-speed-critical execution path: https://youtu.be/KHlI5NBbIPY?si=VjFs7xVN0GsectHr


Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: