What causes the weather? (not the seasons)

  • #1

Summary:

Why can the weather be drastically different on July 31st 2020 compared to July 31st 2019?
Hello.

One winter can be mild and snow free, while the next winter is a frozen wasteland. One summer can be blistering hot, while the next is rather cool. More specifically, if you take that example down to the day, then why can the weather be drastically different on July 31st 2020 compared to July 31st 2019? The earth's tilt and distance from the sun is no different between those dates, and solar output is seemingly about the same for those two dates. So what changed between those dates to cause, let's say, a massive 30 degree temperature change? In other words, why wouldn't the weather be exactly the same on those two dates?

When I've posed this question to a couple of climatologists, I received the suspected answers of ocean currents, uneven heating, cloud formation, etc, yet, none of those reasons actually answer my question. Those answers are symptoms, not causes.

I suspect the answer is fluctuations in solar radiation, but both those climatologists denied that. So what's the answer?
 
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Answers and Replies

  • #2
Drakkith
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When I've posed this question to a couple of climatologists, I received the suspected answers of ocean currents, uneven heating, cloud formation, etc, yet, none of those reasons actually answer my question. Those answers are symptoms, not causes.
I suppose the most fundamental 'cause' that I can think of is that the Earth's surface has no 'symmetry' over time. That is, as time passes, Earth's surface develops changes that make it slightly different from one second/hour/day/year to the next. This happens in everything from the elevation of an area of land, to the amount of water in the atmosphere over a location, to the concentration of gasses in the atmosphere, to many many other factors. So it's no surprise that the weather isn't the same.
 
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  • #3
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So many factors ...

a) The Earth's position differs by ##1/4## day each year, along its elliptical orbit,
b) The Moon's position differs by ~12 days per year,
c) What the weather (worldwide) was like, yesterday. <<--- most of it.
d) water.

Ah, you're asking about seasonal variations, year to year. Ask a climatologist.

I think a decade or so ago, the UK had a (for them) large amount of snow during the winter.

What had happened was that, because of global warming, more of the Arctic ice cap had melted than usual (also Greenland) during the summer ;

The melt flowed into the Atlantic, mixing with the Gulf Stream ;

The Gulf Stream cooled, and returned back to the tropics before it got to England ;

The breeze reaching the shores was cooler ;

So, they got more snow (and less rain).

When I've posed this question to a couple of climatologists, I received the suspected answers of ocean currents, uneven heating, cloud formation, etc, yet, none of those reasons actually answer my question. Those answers are symptoms, not causes.

I suspect the answer is fluctuations in solar radiation, but both those climatologists denied that. So what's the answer?
Curious why you find their answers "suspect". They seem pretty climatey to me.

As far as solar radiation is concerned, Wikipedia probably has you covered in regards comparisons year-to-year. If you want to find out why there are solar fluctuations, we have "Astronomy and Astrophysics", as well as "Quantum stuff" forums.
 
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  • #4
Andrew Mason
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Solar output could certainly can affect weather patterns and climate. But the variation in solar energy output is fairly small: ≈.1% over the 11 year cycle. However, UV fluctuation is more significant. See this NASA site.

The weather is generally driven by solar energy but there is going to be a range of temperature, precipitation, and air movement at a given location without any significant change in the amount of solar energy reaching the earth. Weather depends on many variables: air temperature, land temperature, ocean temperature, temperature gradients, water vapour concentration, air pressure and air pressure gradients, air currents, ocean temperature, coriolis effect on air and water movement, proximity to mountans, location of clouds, time of day etc.

Even drastic. sudden changes, such as a 40 degree C temperature change in 24 hours, which has been known to occur on the prairies, is within the range of normal variation.

In order to determine whether there is something driving global changes in weather one has to study global weather patterns.

AM
.
 
  • #5
Thank you all for the replies. Unfortunately, the answers aren't actually addressing the scenario I pointed out. In addition, answers such as air temperature, land temperature, ocean temperature, temperature gradients, water vapour concentration, air pressure and air pressure gradients, air currents, ocean temperature, coriolis effect, etc, are all symptoms. I'm looking for the cause.

I'll post the question again:


One winter can be mild and snow free, while the next winter is a frozen wasteland, and vice versa. One summer can be blistering hot, while the next is rather cool, and vice versa. More specifically, if you take those examples down to the day, then why for example can the weather be drastically different on July 31st 2020 compared to July 31st 2019? The earth’s tilt and distance from the sun is no different between those dates. The earth’s topography hasn’t changed between those dates. The known solar output is about the same for those two dates. So what was different between those dates to cause for example, a massive change in precipitation and 30 degree temperature change? In other words, why wouldn’t the weather be exactly the same on those two dates, or any other two dates that are exactly one year apart?

Some possible answers that I’ve thought of:


1) A type of fluctuating solar output to which we are aware of, but are underestimating its affect on earth’s climate.


2) A type of fluctuating solar output to which we are UNaware of, to which drastically affects the climate.


3) As our solar system rockets through space at 800,000 km/hr, our atmosphere encounters “random” pockets of hydrogen, helium, electromagnetic radiation, magnetic fields, neutrinos, dust, dark matter, dark energy, cosmic rays, etc, etc. What affect would those have on earth’s atmosphere and climate?


4) Under water volcanoes and heat vents causing variable oceanic temperature differences.
 
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  • #6
DaveC426913
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I think you are looking in the wrong place for cause.

Weather is a very good example of a chaotic phenomenon. Very small differences in initial conditions result in very large differences in outcome. And it's non-linear.

Every day of weather is part of the 'input' for the following day's weather.

Multiply that by 365 iterations and you see that the input, and therefore the outcome, of August 1, 2020 has very little in common with August 1, 2019.

Even if you eliminated all the cyclic and non-cyclic variables you mention (say, via a simulation), you would find it would take a long time for such patterns to stabilize.
 
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  • #7
BillTre
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One winter can be mild and snow free, while the next winter is a frozen wasteland, and vice versa. One summer can be blistering hot, while the next is rather cool, and vice versa. More specifically, if you take those examples down to the day, then why for example can the weather be drastically different on July 31st 2020 compared to July 31st 2019? The earth’s tilt and distance from the sun is no different between those dates. The earth’s topography hasn’t changed between those dates. The known solar output is about the same for those two dates. So what was different between those dates to cause for example, a massive change in precipitation and 30 degree temperature change? In other words, why wouldn’t the weather be exactly the same on those two dates, or any other two dates that are exactly one year apart?

Some possible answers that I’ve thought of:

1) A type of fluctuating solar output to which we are aware of, but are underestimating its affect on earth’s climate.

2) A type of fluctuating solar output to which we are UNaware of, to which drastically affects the climate.

3) As our solar system rockets through space at 800,000 km/hr, our atmosphere encounters “random” pockets of hydrogen, helium, electromagnetic radiation, magnetic fields, neutrinos, dust, dark matter, dark energy, cosmic rays, etc, etc. What affect would those have on earth’s atmosphere and climate?

4) Under water volcanoes and heat vents causing variable oceanic temperature differences.
Your scenario lacks enough detail (location where weather is recorded, local/regional geography, weather systems in previous days, weather conditions in local and neighboring areas, ...) to provide any realistic possibility of answering your question and relying in most cases on more removed astronomical "causes".
In addition, you are (rather arrogantly) rejecting any possible explanations that involve the details that are often involved in weather conditions: geography, pre-existing conditions from previous days, understanding the intricacies of how the global heat engine drives global weather patterns by its interactions with local and neighboring conditions geography.

Your search for these answers is doomed if you are only looking for particular pre-determined answers.
 
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  • #8
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Thank you all for the replies. Unfortunately, the answers aren't actually addressing the scenario I pointed out.
Some of the answers addressed the title of the post ; some of the answers addressed the first part of the post, ie: from year to year in current times.

Then, you've got a third one in a post that only stayed up a few minutes earlier on today, where you claim to have been talking about the weather in pre-anthropic times.

I'll post the question again:
No need, most of the people here are literate. In light of the self-deleted post, you might consider re-reading your own, first.

<snip>

Some possible answers that I’ve thought of:

1) A type of fluctuating solar output to which we are aware of, but are underestimating its affect on earth’s climate.

2) A type of fluctuating solar output to which we are UNaware of, to which drastically affects the climate.

3) As our solar system rockets through space at 800,000 km/hr, our atmosphere encounters “random” pockets of hydrogen, helium, electromagnetic radiation, magnetic fields, neutrinos, dust, dark matter, dark energy, cosmic rays, etc, etc. What affect would those have on earth’s atmosphere and climate?

4) Under water volcanoes and heat vents causing variable oceanic temperature differences.
You seem to think that "climate" is separate from its components, rather than a result of same. We are technologically advanced enough that we would notice 1,2's effect, either directly on the components or directly on the stuff we use to measure things with ; 3 is a wonderful bit of fare for SF and does happen, and the reason we know it happens is because we have instruments (and eyeballs) that detect such things and their actual interactions. And for 4 see 1.

PS: you forgot "dark matter".

The problem of global warming is that the atmosphere is warming up. Why would any "mysterious" effects warm the atmosphere, yet leave alone gases in jars, test tubes, etc.

Anyways, do you mind if I ask you a question ? Is the important bit "What can I/we do to reverse/mitigate the phenomenon and its effects?" or is the important bit "I didn't do it ; you can't prove it".

[note to OP, mods, et al : portions of this post are in response to a deleted post by the OP, which is why the seeming off-topicness of some of the rhetoric. No malicious intent on this end that I'm aware of, nor any implied on the OP's part.]
 
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  • #9
Whew. That's all a lot to digest. Thank you to all.

Hmmm27, I didn't delete my first reply. It was deleted by a mod.

In regards to your question: I'm just trying to find out if all variables are considered and understood when it comes to the climate. For example, some of the possibilities I mentioned previously (to which your reply to each is mainly satisfying to me). More importantly, I'm trying to find out if I'm missing the obvious. lol

Dave,

What exactly is the cause of those very small differences in initial conditions that you speak of? Also, with the known said differences, then shouldn't the outcome be predictable? Yet, it seems it's not. For example, let's take this scenario:

"One summer can be blistering hot, while the next is rather cool, the next is blistering hot, etc, etc"

Why isn't the summer always getting colder, or always getting hotter? What causes such massive temperature extremes (both ways) when comparing one summer to another?
 
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  • #10
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Hmmm27, I didn't delete my first reply. It was deleted by a mod.
Ah, good, then my post is probably safe from same, and I could have skipped the mild guilt trip.
In regards to your question: I'm just trying to find out if all variables are considered and understood when it comes to the climate
What question would that be, again ?

Unless you can actually point to the space monsters shooting mystery-rays at the planet, we're stuck with global warming being anthropogenic in cause. Occam's Razor ("If it looks like a duck and quacks like a duck, it's probably not a '65 Camaro")
 
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  • #11
Ah, good, then my post is probably safe from same, and I could have skipped the mild guilt trip.
What question would that be, again ?

Unless you can actually point to the space monsters shooting mystery-rays at the planet, we're stuck with global warming being anthropogenic in cause. Occam's Razor ("If it looks like a duck and quacks like a duck, it's probably not a '65 Camaro")
I elaborated on my question in my previous post (post#9). It's in my reply to Dave.

Where can I get my hands on one of those mystery rays? :smile:
 
  • #12
256bits
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Why isn't the summer always getting colder, or always getting hotter? What causes such massive temperature extremes (both ways) when comparing one summer to another?
You sure picked a difficult subject.

The analysis of a Complex System such as the interaction of the atmosphere with land masses and the oceans to equalize energy and temperature differences around the world is indeed a grand undertaking. And not completely understood. Solar irradiation is the main driver as an energy input, and radiation back into space the main, if the only, energy output, with the land masses, and oceans acting as the main energy sinks or stabilizers.

As @Andrew Mason pointed out, with a reference to the link provided, the cyclic changes in solar output was not really something previously all that important to be considered, as that was a variable 0.1 %. The link does provide some useful information as to what can be explored in that area, of upper atmospheric influences upon the lower atmospshere. You won't find a complete answer quite yet in this area. Fluctuating output that we are aware of, and that which we are are unaware of , I would think fall under the same category, since data collection would turn the latter into the former - by the question does remain how much can this affect global climate on a cyclic basis and is it significant versus the other 99.9% of irradiation received.

https://oceanservice.noaa.gov/facts/ninonina.html
Just a short note on how oceans play a great part in weather patterns globally, for extended periods of time.
You might want to investigate that further as to why the this occurs - ie change in surface ocean temperatures as I don't know the actual dynamics behind it.

Underwater volcanoes can churn up the different temperature layers of ocean, but I would expect more localized effects. Above ground volcanoes and their effluent spewing into the air, I am sure you are aware, do have an effect on global temperatures, for years if a large outburst.

You can look up Complex Systems.
And also Chaotic systems
with the standard wiki links as starters.
Note that the atmospheric interactions are definitely a complex system, with undertones of chaotic behavior, since it does not act as the normal sense of the limited chaotic system with a Lorenz attractor.
 
  • #13
DaveC426913
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What exactly is the cause of those very small differences in initial conditions that you speak of? Also, with the known said differences, then shouldn't the outcome be predictable?
Sharpen a pencil and stand it on a table on-end.
Balance a marble on the tip of the pencil.
Predict which way they will fall.
Plot the results for successive tries.

Change the parameters, say by re-sharpening the pencil or using a different marble.
Plot the results again.

Do you think that changing the parameters ever so slightly will give more predictable results?
Do you think you can eliminate the parameters? Say, sharpen the pencil down to one atom?
Do you think that, if you can sharpen the pencil down to one atom you will then get repeatable, predictable results?
Do you think this fine-tuning is a battle you can ever win?

... shouldn't the outcome be predictable? Yet, it seems it's not.
In theory, it is predictable. Even chaotic systems are deterministic.
But theory is not practice.
 
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  • #14
Thanks again for the replies. I had to take a break to tend to my brain bleed on the matter. lol

I could be totally wrong, and I mean no offense, but it seems my question remains unanswered. Unless of course, it has been answered, but I'm not understanding the answer???

I'll narrow down my query to just the following:

"One summer can be blistering hot, while the next is rather cool, the next is blistering hot, etc, etc"

What causes such massive temperature extremes (both ways) when comparing one summer to another?


It seems to me that the summer temperature extreme should only be going in one direction, yet it often reverses, and dramatically so. Also, it seems to me that such a massive (and reversing) climate shift in my summer scenerio would require a massive (and fluctuating source). Yet, I'm not seeing said massive source.
 
  • #15
DaveC426913
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"One summer can be blistering hot, while the next is rather cool, the next is blistering hot, etc, etc"

What causes such massive temperature extremes (both ways) when comparing one summer to another?
It's not from one summer to another though.
It's from one week to another.

Every summer has hot and cool periods, they just don't always occur in the same week of each year.

Look at the average temperature over the summer of several years, you will find that the average doesn't vary much. 2019 might have had a cool July and a blistering August, then 2020 might have a hot July with a cool August.
 
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  • #16
Yes, I've considered that Dave, and I'm still mulling that over.

For some reason, I can't help thinking that there are other variables that are either being missed, or underrated. I don't know. It could be due to the fact that when I visit a web site that has scientists discussing and debating climate issues, even the tiniest aspects of our climate leads to a deep rabbit hole of scientific discussion that is full of debate, doubt, assumptions, and a lot of "maybes". Or, I just can't seem to fathom how there can be such drastic climate differences when the sun, moon, and the earth are in the exact same position compared to the previous year (or there about).

Ugh. I think I need a drink now :smile:
 
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  • #17
hutchphd
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Think of a system of coupled harmonic oscillators of different natural frequencies. The overall motion of any one oscillator can be wildly variable. If there are nonlinearities the motion can become essentially unpredictable.
The amazing thing about climate is not the instability but the relative annual stability!!!. I suppose this has to do with how long this thing has been running.....or it could be selection bias......we wouldn't be here if the climate fluctuated much larger. I am sure folks have considered this..
 
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  • #18
jrmichler
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Unless of course, it has been answered, but I'm not understanding the answer???
Yes.

Weather is a chaotic system. Chaos is a field of mathematics, and is completely different from what non-mathematicians think of as chaos. A chaotic system is completely deterministic, but impossible to predict (WAAY oversimplified, but I'm trying to make a point).

I suggest highly recommend reading a book on the subject. Amazon has a large selection of books that come up using search terms nonlinear dynamics and chaos. I have a copy of one them, Nonlinear Dynamics and Chaos by Thompson and Stewart. It's a good book, although a newer book might be better.

If you just want a quick read, search butterfly effect. The Wikipedia entry is good. Just be aware that some of the words in the Wikipedia article are very specific and very important. Words like deterministic and nonlinear.
 
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  • #19
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For some reason, I can't help thinking that there are other variables that are either being missed, or underrated.
If we're actually discussing "global warming", it's the first time in recorded history that mankind has managed to screw up the entire planet, not just bits and pieces of it - a new thing for everybody.

You could go towards religion for answers : outside the scope of these fora, but some of them have been around a *very* long time. Perhaps they know how to deal with something new. The major ones have pretty major science departments, too. I don't think there's any that regard the sciences as an actual enemy, despite the obvious that the more we know the more we can mess things up.

I don't know. It could be due to the fact that when I visit a web site that has scientists discussing and debating climate issues, even the tiniest aspects of our climate leads to a deep rabbit hole of scientific discussion that is full of debate, doubt, assumptions, and a lot of "maybes".
Some (perhaps most) of that is errata. (I guess I should mention that I'm not personally a scientist : I just hang out here for the ambience - it makes me feel smarter. Lots of dedicated sites are like that, I imagine.)

Or, I just can't seem to fathom how there can be such drastic and climate differences when the sun, moon, and the earth are in the exact same position compared to the previous year (or there abouts).
Umm... the Earth is in (more or less) the same place every year because that's how we defined the year. In fact, every year at the exact same place our planet presents a different quarter to the Sun. Meanwhile, in direct opposition to what you state, the Moon is definitely *not* in the same place every year.
 
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  • #20
I've only got a moment for another reply, so for now:

Hmm27,

I obviously worded that wrong, but you know what I meant.
 
  • #21
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I actually don't : since the Earth's orbit is elliptical it means that there's a (more or less) 4 year cycle of being a little closer or farther away than the previous/next year on the day in question. (and that cycle moves a day every 100 years as well, which is then corrected for).

That being said, while the climate trend is sadly (or fortunately: means it's possible to do something about it) anthropogenic, weather variations on a daily, or even seasonal basis are almost entirely caused by water in various forms, being in different places at different times in different phases. That's my take, anyways. If you seriously expect the same cloud-that-looks-like-a-floppy-eared-dog to be in the same place in the sky at the same time every year, then your basic understanding of how things work needs a bit of work, itself.
 
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  • #22
I've been comparing two points in time (about a year apart) when the distance from the earth to the sun is exactly the same.

Anyway, I'm going to to try and refine my question, and suspect the new question will be geared toward predictability and chaotic systems. So far, it seems I may have been trying to find order in a chaotic system. More specific to that, I'm wondering why the climate in of itself is chaotic. Doesn't chaos imply at least 1 "random" element? If so, what is the random element(s)?
 
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  • #23
jim mcnamara
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Since the OP appears to be unaware of basic astronomy, calendrics, geology and some other things

Please READ these things instead of telling us how we are missing something. Otherwise please find some non-science forum to answer your questions

PS: planets do not line up very often. Like once in thousands of years as seen from Earth. I'm not citing any reference but you can look up 'planet conjunction' Moon, Sun, Earth conjunctions are called spring tides. And they do not match our calendar.

Short, correct answers for 'positions of planets, orbits, local weather etc'


Learn about how our calendar and the fact that Earth's orbital position, years, and days are out of sync with the Gregorian calendar. Years are more of a convenience than a precise thing
The tropical year (what you probably think of as a year) is equal to 365 days, 5 hours, 48 minutes, and 46 seconds, or 365.2422 days. And there is further sloppiness - leap seconds (not leap years)

Long term messiness see Milankovitch cycles, Ice Age cycles.
Gregorian calendar (our current calendar) --
https://en.wikipedia.org/wiki/Gregorian_calendar
Milankovitch cycles --
https://climate.nasa.gov/news/2948/milankovitch-orbital-cycles-and-their-role-in-earths-climate/
Ice Ages --
https://en.wikipedia.org/wiki/Ice_age
Short term messiness --
Butterfly effect --
https://en.wikipedia.org/wiki/Butterfly_effect
Frost pocket -- local topology and surroundings
http://www.oakleafgardening.com/glossary-terms/frost-pocket/
Heat island --
https://www.epa.gov/heatislands
 
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  • #24
Jim,

I only used the "year" term to generally describe a time frame to which the distance from the earth to the sun is exactly the same.
 
  • #25
jim mcnamara
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That is not well defined as well. Orbital precession is one reason. You need to read and use use a lot less of 'what you mean' and your 'personal definitions' because you treat them as if we know them and they are correct. We cannot help you otherwise.

Just sayin'.
 
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