57
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Why is the pond in my backyard not frozen when it is -15 °C (5 °F) outside?
Water is a rather strange substance. With most substances, the solid phase is denser than is the liquid phase. This is not the case with water. Ice is less dense than liquid water. A side effect of ...
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55
votes
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How it's possible to measure temperature 2000 years ago with such precision?
How it's possible to measure temperature 2000 years ago?
Sans the technology used by Bill and Ted ("Bill and Ted's Excellent Adventure"), it obviously is not possible to directly measure ...
- 23.1k
53
votes
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Why is the pond in my backyard not frozen when it is -15 °C (5 °F) outside?
Water melts at 0 °C (32 °F) but freezing is a more complicated affair. It is safe to say water gains the ability to freeze at 0 °C, but it can get much cooler before it actually does so resulting in ...
- 14.1k
41
votes
Why would it be drier indoors during the winter vs the summer?
The only physics you need to know is that if the temperature is higher the air† can hold more water vapour (the gaseous phase of water). Cool molecules don't have enough energy to free themselves from ...
- 11k
39
votes
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I just read news that Antarctica had set a new record high temperature, above 18 °C. How can this be the case if it is currently winter there?
You just read the news too fast. WMO announced that, after evaluation by a committee, they have validated the 18.3°C temperature recorded in February (i.e., in summer) last year:
GENEVA, 1 July 2021 (...
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38
votes
Does human body temperature impact climate change?
Does human body temperature impact climate change? Directly? It's not even a blip. The Earth's population is 7.6 billion. With each person radiating about 80 watts (basal metabolism), that's about 600 ...
- 23.1k
37
votes
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Why is geothermal heat insignificant to surface temperature?
One kilometer of rock is actually a lot to dig through to get to that very warm condition.
The key quantity here is heat flux. The crux of the matter is:
Geothermal heat flux is only a small fraction ...
- 3,666
36
votes
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Why aren't weather balloons left in the atmosphere permanently?
In addition to radiosondes that do a single ascent over a few hours, there are also driftsondes that stay in atmosphere for days or weeks, typically with their buoyancy set up to track a particular ...
- 3,940
30
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Why are mornings cooler than nights?
The Earth is always radiating heat to the space. But in the day the Sun delivers some heat. The net heat flux is then defined as the sum of those two factors. If the energy delivered by the Sun is ...
- 638
30
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Why does the temperature change about every 50-100 meters near hills
To extend @Poutnik's invisible river analogy, the cold air can also 'pool' in small dips.
On clear nights, temperature fluctuations are quite a frequent occurrence due to radiative cooling. If the ...
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28
votes
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How to interpolate scattered data to a regular grid in Python?
It is straightforward to do so with numpy, scipy.interpolate.griddata, and matplotlib. Here ...
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25
votes
Why aren't weather balloons left in the atmosphere permanently?
It depends on what each weather balloon is measuring; what data they are capturing.
Most weather balloons are released as specific times during a 24 hour cycle. Such balloons measure altitude, ...
- 24.6k
24
votes
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Why was there a negative temperature anomaly between 1950 to 1980?
This phenomenon is known as global dimming.
It was due to the particles and aerosols mostly released by combustion of fossil fuels such as diesel. Those particles block the radiation from the sun, so ...
- 7,669
22
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Why is the pond in my backyard not frozen when it is -15 °C (5 °F) outside?
Due to convection (the cold water sinks while the warm water rises), the entire pond needs to be brought to near-freezing temperatures before the surface can freeze. With only the top of the pond in ...
19
votes
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What was the highest temperature ever recorded on the surface of Earth?
The record the article is referring about seems to be the same as registered at Guiness World Records:
On 13 September 2012 the World Meteorological Organisation
disqualified the record for the ...
- 17.6k
18
votes
If the earth is a globe, what causes temperature differences across lines of latitude?
Polar regions are colder than equatorial ones for a simple reason - geometry.
More specifically, it is caused by the greater angle of the Sun's rays to the surface of the Earth. As you go farther ...
- 3,548
16
votes
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Could this study "totally dismantle" Global Warming claims?
There is several credibility problems with this work.
First, they mention after the title:
Abridged Research Report
but I cannot find any related full work from the authors on the matter. As a ...
- 2,633
15
votes
Why is the pond in my backyard not frozen when it is -15 °C (5 °F) outside?
The water in a pond is in contact with the ground and the ground is not even close to freezing even if the air temperature is 27° below freezing.
- 2,177
15
votes
Does the US National Weather Service use Celsius or Fahrenheit?
That device only shows Fahrenheit
I don't know about the full Weather Service, but that device only shows Fahrenheit measurements. You can see this in the user manual, in the appendix, page 18
- 259
15
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Is there a recent global gridded temperature dataset with 0.1 deg resolution?
The most important reanalysis datasets covering until present time (I'm excluding the others that stop some years before present time) currently available are:
ERA5 by ECWMF: 1979-present (soon 1950-...
- 1,258
15
votes
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Is the global temperature of the earth a physical quantity at all?
There is no unique way to define a global average temperature of the Earth, but that does not mean that calculation of such a quantity is "pointless". If someone tells me that the average ...
- 813
14
votes
Why is it colder in the mountains than at sea level?
The traditional answer basically comes down to the physics concept of adiabatic cooling, a description of which is:
There is less pressure as you go up in the atmosphere (basically due to less air ...
- 8,713
14
votes
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Why does the intensity of sunlight depend on your latitude?
As noted in the comments, this answer applies to things like sun-bathing and solar panels, but it does not apply so much to a specific point-receptor like an eyeball. If all objects in question are ...
- 351
14
votes
Why would it be drier indoors during the winter vs the summer?
Because cooling air tends to take out moisture, while heating air doesn't change the actual moisture levels.
When air gets colder, it can't "hold" as much water vapor (lower saturation vapor ...
- 8,713
14
votes
Why aren't weather balloons left in the atmosphere permanently?
There are several reasons for this. One of them is air traffic concerns. The parts of the atmosphere that are interesting for weather (namely, the troposhere and lower stratosphere) also happen to be ...
- 313
13
votes
How to interpolate scattered data to a regular grid in Python?
You have a lot of options.
The easiest solution for this simple task would be to use a GIS software, e.g. the free QGIS. Add delimited text layer and try raster interpolation. Download a free ...
- 5,936
12
votes
Accepted
Does climate change cause increase in CO2?
One reason is that we know exactly where the current increased CO2 comes from. That is, we know from economic data how much petroleum, natural gas, & coal is extracted and burned. From that ...
- 1,748
12
votes
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Do hurricanes cool the earth?
Hurricanes can be viewed as having primary and secondary circulations. The primary circulation is what we see in satellite photos, comprising the winds and clouds that circle the low pressure zone at ...
- 23.1k
12
votes
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Where on Earth has the least changing temperature?
To answer the first question, yes, there are maps showing the seasonal temperature variation, for example here
Unsurprisingly, the equatorial areas have the least variation because the angle of the ...
- 851
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