38
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Accepted
Why doesn't the sun reach its highest point overhead at exactly 12:00 noon?
It's not a question of latitude but longitude and time zones.
Prior to the advent of railway transportation the time set on clocks varied from towns within close proximity because the clocks were set ...
- 24.6k
30
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Why doesn't the sun reach its highest point overhead at exactly 12:00 noon?
Maybe a map will help visualise this a bit further:
Source: "Solar time vs standard time" by Stefano Maggiolo - How much is time wrong around the world?
As you can see, time zones are according to ...
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22
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Why isn't Summer Solstice plus and minus 90 days the hottest in Northern Hemisphere?
If Summer Solstice around June 21 every year is the longest day of the year and closest to the sun for the Northern Hemisphere, then why isn't it plus and minus 90 days around this date the hottest? ...
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19
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Why doesn't the sun reach its highest point overhead at exactly 12:00 noon?
Time zones explain why you don't observe solar noon at 12:00 exactly, but not why the wall-clock time of solar noon varies with the seasons. In fact, even if you stay in place and don't observe DST, ...
19
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Are there some places near the equator that are hottest in their winter and some that are hottest in their summer? Is there a map of this?
Tropical climates usually aren't subject to typical extratropical seasons and are instead characterized by rainy/dry seasons. However, if you define the "summer" and "winter" ...
- 13.5k
16
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Why wouldn't the earth be "always daytime" if the "daily cycle of sunlight" was drawn full-scale?
The sun is really far away. Thus its rays are essentially parallel at the earth's orbit. So, while the diagram you posted is clearly a bit off in terms of the relative size and distance between the ...
- 11k
13
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Why does winter get colder after the solstice?
Primarily because of inertia. This phenomenon is called seasonal lag.
It is true that the December solstice is the moment that the northern hemisphere gets the lowest total amount of insolation. ...
- 11.6k
11
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Why wouldn't the earth be "always daytime" if the "daily cycle of sunlight" was drawn full-scale?
The sun is about 100 times the size of the Earth (in diameter), and the distance from the sun to Earth is about 100 times the diameter of the sun. Below is an image showing the sun, Earth, and the ...
- 1,207
9
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Why isn't Summer Solstice plus and minus 90 days the hottest in Northern Hemisphere?
It's all about thermal storage/momentum.
Consider spring and fall equinox. They should be the same temperature, right?
On March 20, why are the lakes still frozen? Because the hemisphere spent the ...
8
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What time and date is the sun directly overhead a given place on Earth?
Having the sun directly overhead can happen only between the Cancer and Capricorn tropics. That is, only the places between 23.5° of latitude north and 23.5° of latitude south.
On the Cancer tropic (...
- 17.6k
8
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Why doesn't the sun reach its highest point overhead at exactly 12:00 noon?
Henning Makholm's answer is excellent but omits the elegant definition of the mean Sun, which is what the clock at the Prime Meridian attempts to match:
Consider a first fictitious Sun travelling ...
- 181
8
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Does the amount of UVA radiations one receives depend on the day ot the year?
UVA passes through the atmosphere without losing much intensity, so per quote one it's intensity doesn't change, nor does it's magnitude as a percentage of total insolation vary, much, during the year ...
- 4,260
8
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Where does the sun set?
Where it sets depends on 1) your latitude and 2) the Sun's declination, which varies throughout the year between -23° (December) and +23° (June). Consider the following pictures, taken from A Quick ...
- 748
7
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Why wouldn't the earth be "always daytime" if the "daily cycle of sunlight" was drawn full-scale?
But if you scale up the Sun to it's real size compared to the Earth,
Is pretty big. But then to be realistic in that manner you would also have to scale up the distance from the earth to the sun.
...
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6
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Why wouldn't the earth be "always daytime" if the "daily cycle of sunlight" was drawn full-scale?
Given the known average distance to the Sun, and the radii of Sun and Earth, the basic trigonometry is simple.
If the Earth and Sun were exactly the same size, and there was no atmospheric refraction,...
- 14.2k
6
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Are there some places near the equator that are hottest in their winter and some that are hottest in their summer? Is there a map of this?
The temperate concepts of winter and summer don't quite apply to the tropics, the region between the Tropic of Capricorn and the Tropic of Cancer. That region experiences two maxima and two minima per ...
- 23.1k
6
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Does the amount of UVA radiations one receives depend on the day ot the year?
Reddit user and r/EarthScience mod Halcyon3k pointed me to the following visualization that nicely illustrates Ash's great answer on the fact that "total ground level insolation intensity in $\...
5
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Accepted
Are the length of seasons the same globally?
As has been noted in a comment, it depends on how you define seasons (see https://earthscience.stackexchange.com/a/2603/111).
If seasons are defined in astronomical terms, then they have the same ...
- 5,800
5
votes
Accepted
Why don't all living beings die at night due to lack of oxygen?
The rates at which plants consume CO$_2$ and animals consume O$_2$ is minuscule compared to the vast amounts of CO$_2$ and O$_2$ in the atmosphere. The amount of change overnight is not even ...
- 1,207
5
votes
Accepted
Have the seasons always been?
Has the Earth had it's wobble that causes the seasonal variation in solar energy in the northern and southern hemispheres for it's entire history?
First it depends on how you define the "entire ...
- 511
5
votes
How was Venice flooded?
Venice can't really be flooded by rivers, since there are none worth mentioning throughout the city.
High tides are predictable, yes.
Take a look at how Venice is situated. The historic city is ...
- 726
5
votes
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How was Venice flooded?
If the winds subsided and the flooding was caused purely by tidal effects, which are astronomical events, shouldn't it have been predictable months, if not years in advance?
The tides are only ...
- 23.1k
5
votes
Why does the Indian subcontinent experience it's warmest weather in April and May?
While India is in the northern hemisphere, keep in mind that tropical locations don't usually follow typical seasonal patterns experienced at higher latitudes. Instead, the tropics often have a wet ...
- 13.5k
5
votes
Accepted
How is this global temperature chart compiled?
As stated in your linked article, the graph shows the global average temperature based on ERA5 reanalysis data.
Typically for graphs like this you integrate the surface temperature over the whole ...
- 1,145
4
votes
Sun's Highest Point on June 21
Well, kind of, depending on what you really mean.
We're being rather vague with our terms, and so it shouldn't be surprising if the answer doesn't meet our expectations.
We could interpret all these ...
- 3,548
4
votes
Accepted
What would the equilibrium temperature be at the poles in a world without seasonality?
If we consider that by "Assume daily cycle and convection and so on operate as usual" you meant that all heat transport from/to the pole remain as it is today. Then, we can do a back of the envelope ...
- 17.6k
3
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Why doesn't the sun reach its highest point overhead at exactly 12:00 noon?
Cannot add to the excellent Time Zone, Daylight Savings, and Equation of Time (Mean Sun) explanations here, but I do want to mention something about the original question by Ian Paschal. It appears to ...
3
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Why wouldn't the earth be "always daytime" if the "daily cycle of sunlight" was drawn full-scale?
Because no matter how big the Sun is compared to the Earth, only half the Earth can be facing the Sun at any given time.
Try drawing a diagram where the Sun is much bigger with respect to the Earth. ...
- 171
3
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What are the most similar Earth analogues to Mars' seasonally recurring slope linea?
Analogues to Mars Recurring Slope Linea (RSL) is a current study topic in Antarctica (Dry Valleys). On Earth, analogues are known as water tracks, which are linear zones of higher moisture along ...
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