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I've been a bit confused by what the MMI scale actually is meant to represent. Most descriptions I've seen seem to put emphasis on the intensity of shaking, but they also describe it as specifically a damage scale.

My confusion relates to what the scale is really meant to describe about in earthquake in a given area. Is the end product meant to represent the actual intensity of shaking, or other damaging factors as well (i.e. would things like liquefaction be included in that), or a representation of the actual damage expected (a quake in the middle of the desert would have less potential for damage than one in a populated area, and one in an area with many poorly built buildings would fare relatively worse than one which has a decent seismic code, would those factors have any influence in what the MMI profile of an earthquake looks like)? In other words, what does "earthquake intensity" really mean?

I do understand that actually using the MMI scale is probably a fairly messy and complicated process which is going to involve many factors, of course, but I'm trying to understand better what the scale is meant to actually, ideally, tell you about the earthquake in a given area.

If I see something abandoned that is valuable, I pick it up and either keep it, repurpose it, or find its owner. How can something like an abandoned Roman villa in the UK be found with intact mosaics or even things such as coins or children's shoes? It seems to me that the first thing locals would do once the Romans left would be to scavenge anything left behind, even looking for places where they might have buried valuables for later retrieval. Why are some sites left alone long enough to collect sediment layers, especially at sites where there is subsequent human habitation across thousands of years? I don't get it.

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Prior to 12,400 years ago and up until 23,000 years ago, there was an Ice Age. At 23,000 years ago, that's when the Ice Age was at a maximum, and the ocean levels were 400 feet shallower. This means that there was a lot more land, and more rivers in those days. Also, all of today's rivers are a subset of all the rivers that existed 23,000 years ago. So are there any new rivers formed since 23,000 years ago, and if so, how did that happen?

Recent study that hypothesized the theoretical limit on human lifespan due to accumulation of somatic mutations, especially in non-mitotic cells (e.g. heart and brain). https://www.nature.com/articles/s41514-026-00421-6

Why would repair mechanisms fail continually in a way that allows them to accumulate? I understand proofreading enzymes are imperfect, but this isn't like mitosis where if you miss it welp too bad the mutation is permanent now. Presumably in non-mitotic cells they have proofreading enzymes going up and down the entire DNA strand repeatedly forever (as long as the cell continues to live)? Why would they keep missing errors despite checking multiple times AND letting them accumulate?

Storm's chasin's my thing, and, even tho I do alot more chasin, than catchin, I've been lucky to observe afew flash flood events.

I've noticed a conspicuous pattern, where "waves" will come down, an already flooded wash, nearly DOUBLIN tha flow. These waves seem to come at very regular intervals, almost lika bucket, at'a water park, that tips whenit gets full.

I'm sure this phenomenon is well-known, amongst the experts, and well-documented. Hopefully, some1 with this knowledge can enlighten me... 🤔

I know that it isn’t all medicine and that there’s other things inside the vaccine fluid itself but unless I’m mistaken aren’t cultures of the vector grown and then added to the other fluid? Do they put the culture in a blender or something?

Heat pumps are, in essence, devices which exploit the chemistry of the refrigeration cycle to cause one thing to get cold while another thing gets hot.

While we already use these to make crazy-efficient air con units, refrigerators, and water heaters, but why are all electric stoves sold nowadays still using resistance coils to generate heat, rather than using a heat pump?

It is well known how us mammals use our body temperature to prevent infections and raise it to combat them, so wouldn't cold-blooded animals be much more propense to suffer viral and bacterial diseases?

Question in title. Drugs from widely different classes and indications seem to cause photosensitivity and I’m curious as to why and how that is. Thanks!

I am watching project hail mary and in order to save the earth and erid they have to go fishing to collect "predators" for the astrophage. Predators being bacteria?

Obviously this is sci-fi but...

Does earth have bacteria in its atmosphere or in the clouds?

With the recent Canadian Wildfires happening again. I am wondering if this was a thing that happened often in the 90s/00s/etc?

Maybe back then we didn't know any better due to lack of information flow and perhaps a lack of technology to accurately detect the air quality and such?

Anyways, hope everyone is staying safe in the areas affected by these wildfires.

Be sure to wear a mask when outdoors, or just try to limit your times outdoors as much as possible.

I can understand why diarrhea happens.
But sometimes diarrhea is classified as “explosive.” This is when it erupts out of the anus with force.
Genuinely asking - why the force? What purpose does that serve? What signals are happening in the body telling it that forcing the poop out is best?

Regular diarrhea already leaves the body so quickly.

Side question: When and how did we discover that it isn't equally distributed?

I used the earth sciences flair but I'm not sure if that's the correct flair for this question.

For example, say I am making brownies from a box.

16 servings per box
130 calories per serving
2,080 calories total

I assume these numbers are for finished baked brownies. But if I were to make mix everything into the batter and eat the batter instead is it approximately the same amount of calories? Or does the act of baking change the calories from the ingredients?

Ingredients:
1/4 cup water
1/3 cup vegetable oil
1 egg
1 Box Brownie mix

When I was growing up we were constantly hearing about how acid rain was going to be such a problem for the environment. Then, seemingly out of nowhere, it virtually vanished from the news. What exactly happened?

Edit: Scare was the wrong word to use in this instance.

"Acid rain crisis" would be more appropriate.

Would I find measurable radioactivity in random places? Or from electronics? I don’t live near a reactor.