What causes the weather? (not the seasons)

[Seth Anthony]

TL;DR 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?

 

[Drakkith]

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.

 

[hmmm27]

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.

 

[Andrew Mason]

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
.

 

[Seth Anthony]

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.

 

[DaveC426913]

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.

 

[BillTre]

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.

 

[hmmm27]

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.]

 

[Seth Anthony]

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?

 

[hmmm27]

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")

 

[Seth Anthony]

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?

 

[256bits]

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.

 

[DaveC426913]

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.

 

[Seth Anthony]

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.

 

[DaveC426913]

"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.

 

[Seth Anthony]

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 website 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

 

[hutchphd]

Think of a system of coupled harmonic oscillators of different natural frequencies. The overall motion of anyone 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..

 

[jrmichler]

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.

 

[hmmm27]

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 website 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.

 

[Seth Anthony]

I've only got a moment for another reply, so for now:

Hmm27,

I obviously worded that wrong, but you know what I meant.

 

[hmmm27]

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.

 

[Seth Anthony]

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)?

 

[jim mcnamara]

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-Earth's-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

 

[Seth Anthony]

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.

 

[jim mcnamara]

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'.

 

[Seth Anthony]

I understand what you mean. That's precisely why I also gave the other scenario of comparing the general weather conditions from one summer to the next as well. I'm finding it difficult to get my point across. I'll try one more time:The scenarios I presented are examples of how unpredictable and chaotic the climate system is. It seems to me that if we truly understood all the factors, then the climate system/weather should be a lot more predictable and uniform. Yet, it’s highly chaotic and highly unpredictable. As such, does that mean there are 1 or more random factors that we’re unaware of, or random factors that we are aware of, but miscalculating or underestimating their affect?

OR:Is it a matter of “predictably”, “uniformity” and "chaos"are subjective terms in this regard, and my massive weather changes scenarios fall within the known parameters? In other words, it's more predictable and uniform than I think?

 

[DaveC426913]

Yet, it’s highly chaotic and highly unpredictable. As such, does that mean there are 1 or more random factors that we’re unaware of, or random factors that we are aware of, but miscalculating or underestimating their affect?

This is a basic misconception.

A system doesn't have to have random factors or factors we are unaware of in order to be effectively unpredictable.

We first have to disabuse you of such preconceptions.

 

[Seth Anthony]

Well at that point, we would have to define what exactly we mean by "random", and I sure the heck don't want to go there.

Is it more a matter of what I said in my previous post? That is:

Is it a matter of “predictably”, “uniformity” and "chaos"are subjective terms in this regard, and my massive weather changes scenarios fall within the known parameters? In other words, it's more predictable and uniform than I think?

 

[lomidrevo]

@Seth Anthony, what is your actual goal in this thread?
You already received tons of very good answers, and you keep to ignore them. Endless restating of your question will not help you to get deeper understanding of the topics involved. You should now take the hints given to you more seriously, and read about the concepts. Otherwise the discussion is pointless.

 

[Seth Anthony]

I'm not ignoring them. I believe I've come to the point to which I stated in my previous post. That is:

The terms of “predictably”, “uniformity” and "chaos"are subjective in this regard, so it seems "my massive weather changes" scenarios fall within the known parameters. In other words, the climate (in the known parameters) is more predictable and uniform than I thought.

 

[TeethWhitener]

Wait, are you only comparing the temperature at one location on the Earth year after year, or are you looking at the global average? Because the global average is fairly predictable (no wild 30-degree swings year-over-year). The other one is not: you do know that black cars sitting in the sun get hotter than white cars, right? And that things on the Earth are different colors? And that things like clouds and ice are really reflective, so they bounce sunlight back into space more easily than bare land or water? And and and and and...The weather would be variable even if the system were not chaotic, because the globe is variable.

 

[lomidrevo]

The terms of “predictably”, “uniformity” and "chaos"are subjective in this regard, so it seems "my massive weather changes" scenarios fall within the known parameters. In other words, the climate (in the known parameters) is more predictable and uniform than I thought.

This doesn't make sense to me. What exactly is subjective about these terms? Additionally, the discussion started about weather and now you make conclusions about climate. It is not the same.
You can make whatever statements you like, but do they improve your actual understanding?

 

[Drakkith]

The scenarios I presented are examples of how unpredictable and chaotic the climate system is. It seems to me that if we truly understood all the factors, then the climate system/weather should be a lot more predictable and uniform. Yet, it’s highly chaotic and highly unpredictable. As such, does that mean there are 1 or more random factors that we’re unaware of, or random factors that we are aware of, but miscalculating or underestimating their affect?

We don't understand all the factors. For example, we only recently (within the last decade or so) managed to accurately model a tornado and account for which inflows and outflows power it. And this is a fairly small local phenomenon. There are many factors to account for, and we just don't know about all of them nor do we fully understand the ones we do know about.

On top of that, we have an issue of how we model weather and climate. Ideally, we would use 'first principles' in our computational models since they should give us the most accurate results. However, this is often impossible due to the sheer number of different parameters and particles we'd have to use, so we have to develop shortcuts that make it possible to make a model in a usable time frame. But these shortcuts aren't as accurate, and sometimes they are just downright wrong.

Don't fully believe me? Then try developing a simulation that can make an accurate model of the airflow produced by a fan placed in a 1x1x1 meter sealed box. First try it by modeling every single gas particle. When your computer melts or crashes from memory overflow you'll understand what I'm saying.

In any case, that only addresses how we model and predict the weather/climate. It does nothing to address your original question.

 

[Genava]

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

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?

Basically the reasons for yearly variability in temperature are often explained by some variability in the way the energy is distributed within Earth's system. Higher latitudes are actually dependent on the energy conveyed by the ocean and the air circulation cells from the Equator and Tropics to the Poles. Variations in temperature in a region between two years is often caused because of a variability in the way other regions received or kept thermal energy. There is a chain of causes and effects to reach a certain temperature in a region and this chain of causes and effects depends on other regions too.

I understand this is not something easy to understand so I can give you a few excerpts from various institutional websites to draw a general picture of the Earth's system.

There are differences between external and internal forcings:

There are numerous mechanisms that may produce climate variations or change. One is external forcing, which contains both natural and anthropogenic sources. Examples of natural external forcing include solar variability and volcanic eruptions. Examples of anthropogenic forcing are from changing concentrations of greenhouse gases and aerosols, and land cover use produced by human activities. A second involves internal mechanisms within the climate system that alone can produce climate variations. Internal mechanisms include processes that are due primarily to interactions within the atmosphere as well as those that involve coupling of the atmosphere with various components of the climate system. Climate variability due to purely internal mechanisms is often called internal variability.
Source: https://psl.noaa.gov/csi/whatis/

The ocean is important thermal regulator of the Earth's climate because of its large thermal capacity and its large volume, this is why it is nicknamed sometimes "Earth’s biggest heat bucket".

Seasonal temperature extremes are milder near large bodies of water and more extreme further inland because water is slower to heat up and to cool down than air or even land. The ocean (as well as other large bodies of water) have considerable "thermal inertia". They warm slowly as heat is added, but also give up that heat slowly as their surroundings cool.
Source: https://scied.ucar.edu/longcontent/transfer-and-storage-heat-oceans

One way that the world’s ocean affects weather and climate is by playing an important role in keeping our planet warm. The majority of radiation from the sun is absorbed by the ocean, particularly in tropical waters around the equator, where the ocean acts like a massive, heat-retaining solar panel. Land areas also absorb some sunlight, and the atmosphere helps to retain heat that would otherwise quickly radiate into space after sunset.

The ocean doesn't just store solar radiation; it also helps to distribute heat around the globe. When water molecules are heated, they exchange freely with the air in a process called evaporation. Ocean water is constantly evaporating, increasing the temperature and humidity of the surrounding air to form rain and storms that are then carried by trade winds. In fact, almost all rain that falls on land starts off in the ocean. The tropics are particularly rainy because heat absorption, and thus ocean evaporation, is highest in this area.

Outside of Earth’s equatorial areas, weather patterns are driven largely by ocean currents. Currents are movements of ocean water in a continuous flow, created largely by surface winds but also partly by temperature and salinity gradients, Earth’s rotation, and tides. Major current systems typically flow clockwise in the northern hemisphere and counterclockwise in the southern hemisphere, in circular patterns that often trace the coastlines.

Ocean currents act much like a conveyor belt, transporting warm water and precipitation from the equator toward the poles and cold water from the poles back to the tropics. Thus, ocean currents regulate global climate, helping to counteract the uneven distribution of solar radiation reaching Earth’s surface. Without currents in the ocean, regional temperatures would be more extreme—super hot at the equator and frigid toward the poles—and much less of Earth’s land would be habitable.
Source: https://oceanexplorer.noaa.gov/facts/climate.html

If you want to visualize some effect of the ocean, NASA made an interesting video on the topic with the title "The Ocean: A Driving Force for Weather and Climate".

Finally, the most important part to understand is the role of air pressure on weather:

Pressure varies from day to day at the Earth’s surface - the bottom of the atmosphere. This is, in part, because the Earth is not equally heated by the Sun. Areas where the air is warmed often have lower pressure because the warm air rises. These areas are called low pressure systems. Places where the air pressure is high, are called high pressure systems.

A low pressure system has lower pressure at its center than the areas around it. Winds blow towards the low pressure, and the air rises in the atmosphere where they meet. As the air rises, the water vapor within it condenses, forming clouds and often precipitation. Because of Earth’s spin and the Coriolis Effect, winds of a low pressure system swirl counterclockwise north of the equator and clockwise south of the equator. This is called cyclonic flow. On weather maps, a low pressure system is labeled with red L.

A high pressure system has higher pressure at its center than the areas around it. Winds blow away from high pressure. Swirling in the opposite direction from a low pressure system, the winds of a high pressure system rotate clockwise north of the equator and counterclockwise south of the equator. This is called anticyclonic flow. Air from higher in the atmosphere sinks down to fill the space left as air is blown outward. On a weather map, you may notice a blue H, denoting the location of a high pressure system.
Source: https://scied.ucar.edu/learning-zone/how-weather-works/highs-and-lows-air-pressure

As you see, it has a huge importance for the wind direction and the way the air mass behave.

BUT the effect goes beyond this, the air masses with a particular air pressure are affected by their surroundings with a different air pressure and are affecting them as well:

When the air in one region is warmer than the surrounding air it becomes less dense and begins to rise drawing more air in from underneath it. Elsewhere cooler denser air sinks pushing air outward to flow along the surface and complete the cycle. The constant movement of these accumulations of air is called Fronts.

What are the Types of Weather Fronts

When large masses of warm or cold air move throughout the atmosphere they carry their own differences and characteristics. The boundary between the air masses is part of the front. Usually, hundreds of miles long, when a front passes through a region, it changes the weather. There are four types of Fronts and they are:

• Cold Fronts-When a cold air mass pushes under a warm air mass forcing the warm air to rise.
• Warm Front-This forms when warm moist air slides up and over a cold air mass.
• Stationary Front– This front occurs when warm and cold air meet and neither air mass has the strength to push the other they remain standing still
• Occluded Front-This front occurs when warm air mass gets caught between two cold air masses. The warm air masses rise and the two cold masses meet in the middle.

What are Cold fronts

When Cold fronts come through the weather becomes windy and gusty. There is a sudden drop in temperatures. Thunderstorms and heavy rainfall with hail can develop. These dramatic changes in the weather are fast and violent. They can move twice as fast as a warm front. Atmospheric pressure changes fast from falling to rising. After the Cold front moves through the area, the temperatures become cooler.

The rain will stop and Cumulus Clouds are replaced by Stratus clouds or with clear skies. On a weather map, the cold front is represented by a blue line. Triangle will show the direction the front is moving in. You will always see temperatures in front of the blue line are warmer than the temperatures in the back of the line after the front moves through. The front will cool the area in that down considerably.

What are Warm Fronts

Warm air fronts move slowly because it’s more difficult for the warm air to push against the cold dense air. The types of clouds that are associated with a warm front are located high in the sky. As the warm front passes over the area the clouds become lowered and rain is more likely.

There can be thunderclouds around this front if the air is unstable. On a weather map that you normally see on the evening news, the warm air front is represented by a red line and the red semi-circles indicate the airflow direction. The temperatures on the ground will normally be cooler in front of the red line than warmer after the front moves through.

What are Stationary Fronts

Stationary fronts happen where the masses of warm and cold air won’t move and are kind of standing off with each other but neither one is strong enough to move the other one aside. This front can stay put for days unless the wind direction changes or the system breaks apart. The weather with this type of front is normally cloudy and rain or snow will often fall according to the temperature.

Especially if the front is in a low atmospheric pressure area. On a weather map, a Stationary Front looks like an alternating red line with semi-circles and blue triangles. The blue triangles point in one direction while the red semi-circles point in the opposite direction.

What is Occulted Fronts

Sometimes cold fronts follow right behind warm fronts. The fronts push against each other but because the cold fronts move faster it will normally take over. This occurrence is called Occulted Front. At an occluded front, the cold air normally forms around low atmospheric pressure and there is often precipitation that follows. Winds will change direction as this front moves through the area.

The temperatures can either cool or warm as it passes through the region. On a weather map, an Occulted Front looks like a purple line that contains half triangles and half semi-circles along it pointing in the direction of movement of this front.

Fronts are Made Up of Air Masses

Air is all around us and when you feel the air start to move it could be that the weather is about to change. The way the air moves effects the weather because wind carries heat and cold temperatures as well as moisture to one place or to another. How these winds pass each other affects a region that day. The air is classified by masses there are four main air masses that are according to the geographical part of the Earth they are associated with.

• Polar Maritime- An air mass that is typically warm and moist
• Polar Continental Is the air that is cold and dry in the winter.
• Tropical Maritime is the air that is warm and moist
• Tropical Continental is the air that is warm and dry

The movement of these Air Masses makes up the Fronts and their interactions with landmasses affect weather in those areas.

The fronts of these air masses can carry pressure differences that make wind happen are caused by differing conditions behind the air in each front. When two of these air masses bump into each other it can create a storm or other change in the weather.

How fast it moves and how different they are in temperature at the time they move into each other dictates the severity of the oncoming weather event. If the two systems collide into each other at too quickly a speed it could cause a cyclone.

Source: https://mywaterearth.com/what-causes-changes-in-weather/

I hope now you are beginning to understand how dependent to surrounding conditions is the weather of a region and why seasons are different year-to-year.

To go further, there are also long-term internal oscillations in the climate system that make each year different to another.

Climate Variability: Arctic Oscillation
https://www.climate.gov/news-features/understanding-climate/climate-variability-arctic-oscillation

Climate Variability: North Atlantic Oscillation
https://www.climate.gov/news-featur...limate-variability-north-atlantic-oscillation

Climate Variability: Pacific - North American Teleconnection Pattern
https://www.climate.gov/news-featur...ability-pacific-north-american-teleconnection

Long Distance Relationships: the Arctic and North Atlantic Oscillations
https://www.climate.gov/news-featur...tance-relationships-arctic-and-north-atlantic

Polar vortex brings cold here and there, but not everywhere
https://www.climate.gov/news-featur...tex-brings-cold-here-and-there-not-everywhere

 

[Evo]

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?

Have you heard of El Niño and La Niña?

What are El Niño and La Niña?
El Niño and La Niña are complex weather patterns resulting from variations in ocean temperatures in the Equatorial Pacific.

Warmer or colder than average ocean temperatures in one part of the world can influence weather around the globe. Watch this Ocean Today video to see how this works.

The term El Niño refers to the large-scale ocean-atmosphere climate interaction linked to a periodic warming in sea surface temperatures across the central and east-central Equatorial Pacific.

Typical El Niño effects are likely to develop over North America during the upcoming winter season. Those include warmer-than-average temperatures over western and central Canada, and over the western and northern United States. Wetter-than-average conditions are likely over portions of the U.S. Gulf Coast and Florida, while drier-than-average conditions can be expected in the Ohio Valley and the Pacific Northwest. The presence of El Niño can significantly influence weather patterns, ocean conditions, and marine fisheries across large portions of the globe for an extended period of time.

La Niña episodes represent periods of below-average sea surface temperatures across the east-central Equatorial Pacific. Global climate La Niña impacts tend to be opposite those of El Niño impacts. In the tropics, ocean temperature variations in La Niña also tend to be opposite those of El Niño.

During a La Niña year, winter temperatures are warmer than normal in the Southeast and cooler than normal in the Northwest.

https://oceanservice.noaa.gov/facts/ninonina.html

This is why the "weather" can vary so much. If after all of the previous posts and this you still do not understand changes in the weather from year to year, it's time to close this thread.

 

[256bits]

Have you heard of El Niño and La Niña?

He should have by now.
I already posted about the subject in #12.You get some likes and responses , but for some reason my post was overlooked completely.
Same information. Different messengers I suppose.

 

[Rive]

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 think this part is, what confusing you. Those things are both cause and effect in the same time: effect of past causes and causes for the future effects.

In short, the cause of (future) weather is, that we do have weather right now