<p>Doing a quick calculation that looks to be around the wet-bulb temperature at the time of observation so that thermometer on the right side should be a hygrometer. Hygrometers measure the level of moisture in the air as opposed to a thermometer that measures the temperature level.</p>

<p>Edit: The calculation was based on a recorded observation scoured from <a href="https://www.timeanddate.com/weather/antarctica/esperanza-base/historic" rel="nofollow noreferrer">here</a> as finding the history of observations at the station was proving difficult. The observation marked a temperature around 64 degrees F with a relative humidity value of 34%. Using <a href="https://www.omnicalculator.com/physics/wet-bulb" rel="nofollow noreferrer">this</a> online based calculator which gives a rough estimate of the Wet Bulb Temperature, the calculated value came out to be 49.47 (F) or 9.7 (C) which was close enough for me to determine that the thermometer on the right was a hygrometer. Aiding that assumption was the fact that thermometers and hygrometers are sometimes paired together for observations.</p>

CC BY-SA 4.0
2020-02-07T22:32:50.653Z
Ah, that makes sense. But the answer could use a bit more detail.
leftaroundabout
CC BY-SA 4.0
2020-02-07T23:30:02.510Z
It would be great if you included a link or an example of the calculation, the OP and other readers will find it more instructive. I have a we/dry setup at home and I always have to read the table on the back of the box to get humidity. If there's an equation or something it would be great to know. Thanks!
uhoh
CC BY-SA 4.0
2020-02-08T00:27:50.393Z
@uhoh: If it is a wet bulb thermometer the relative humidity would be 32% & the dew point would be approx. 1.5 C - according to the spreadsheet I wrote years ago. The relative humidity is vapor pressure divided by saturated vapor pressure @ dry bulb. To get vapor pressure, another 5 or so calculations need to be done: moisture content, moist cont @ wet bulb, enthalpy of vapor press @ wet bulb, enthalpy of liquid water @ wet bulb, enthalpy of vapor press @ dry bulb. Nothing difficult, just time consuming.
Fred
CC BY-SA 4.0
2020-02-08T00:31:23.683Z
@Fred got it, thanks! I'll look around, and if I don't find an existing Q&A then maybe I'll ask a new question.
uhoh
CC BY-SA 4.0
2020-02-08T01:08:19.060Z
@Fred I've just asked: [How is relative humidity determined from a wet and dry bulb readings?](https://earthscience.stackexchange.com/q/19151/6031)
uhoh
CC BY-SA 4.0
2020-02-10T19:25:09.493Z
@leftaroundabout Edited in my process, hope that helps!
Wxboyajm
CC BY-SA 4.0
2020-02-07T19:58:06.220Z
2020-02-10T19:37:48.643Z
2020-02-10T19:37:48.643Z
Wxboyajm
<p>Today, the Argentinian meteorological service tweeted about a new temperature record for Antarctica of 18.3°C, made on the Espezanza peninsula. This was subsequently reported by many other sources.</p>

<p><a href="https://twitter.com/SMN_Argentina/status/1225455484259442691" rel="nofollow noreferrer">twitter.com</a>
<a href="https://public.wmo.int/en/media/news/new-record-antarctic-continent-reported" rel="nofollow noreferrer">wmo.int</a>
<a href="https://www.bloomberg.com/news/articles/2020-02-07/it-s-t-shirt-weather-in-antarctica-as-temperature-breaks-record" rel="nofollow noreferrer">bloomberg.com</a>
<a href="https://www.nytimes.com/aponline/2020/02/07/world/europe/ap-eu-switzerland-un-antarctica.html?searchResultPosition=1" rel="nofollow noreferrer">nytimes.com</a>
<a href="https://www.theguardian.com/world/2020/feb/07/antarctica-logs-hottest-temperature-on-record-with-a-reading-of-183c" rel="nofollow noreferrer">theguardian.com</a></p>

<p>The tweet contained an image of a literal analogue thermometer which did show the 18.3°C... but curiously enough, also <em>another</em> thermometer showing merely 10.0°C.</p>

<p><a href="https://i.sstatic.net/7XnXh.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/7XnXh.jpg" alt="The image tweeted by SMN Argentina"></a></p>

<p>What's that about? Is that 10°C another means of measuring temperature, e.g. some kind of running average temperature? Or is one of the readings simply faulty?</p>

<meteorology><climate-change><temperature><measurements>
What is the second thermometer in the image from the Esperanza Antarctic temperature record?
leftaroundabout
# What is the second thermometer in the image from the Esperanza Antarctic temperature record?

(Asked by: username_0 on 2020-02-07)

Today, the Argentinian meteorological service tweeted about a new temperature record for Antarctica of 18.3°C, made on the Espezanza peninsula. This was subsequently reported by many other sources.

[twitter.com](https://twitter.com/SMN_Argentina/status/1225455484259442691)
[wmo.int](https://public.wmo.int/en/media/news/new-record-antarctic-continent-reported)
[bloomberg.com](https://www.bloomberg.com/news/articles/2020-02-07/it-s-t-shirt-weather-in-antarctica-as-temperature-breaks-record)
[nytimes.com](https://www.nytimes.com/aponline/2020/02/07/world/europe/ap-eu-switzerland-un-antarctica.html?searchResultPosition=1)
[theguardian.com](https://www.theguardian.com/world/2020/feb/07/antarctica-logs-hottest-temperature-on-record-with-a-reading-of-183c)

The tweet contained an image of a literal analogue thermometer which did show the 18.3°C... but curiously enough, also *another* thermometer showing merely 10.0°C.

[![The image tweeted by SMN Argentina](https://i.sstatic.net/7XnXh.jpg)](https://i.sstatic.net/7XnXh.jpg)

What's that about? Is that 10°C another means of measuring temperature, e.g. some kind of running average temperature? Or is one of the readings simply faulty?

**Tags:** meteorology, climate-change, temperature, measurements


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## 1 answers

### Answer by username_1 on 2020-02-07. Score: 6 | Accepted answer

Doing a quick calculation that looks to be around the wet-bulb temperature at the time of observation so that thermometer on the right side should be a hygrometer. Hygrometers measure the level of moisture in the air as opposed to a thermometer that measures the temperature level.

Edit: The calculation was based on a recorded observation scoured from [here](https://www.timeanddate.com/weather/antarctica/esperanza-base/historic) as finding the history of observations at the station was proving difficult. The observation marked a temperature around 64 degrees F with a relative humidity value of 34%. Using [this](https://www.omnicalculator.com/physics/wet-bulb) online based calculator which gives a rough estimate of the Wet Bulb Temperature, the calculated value came out to be 49.47 (F) or 9.7 (C) which was close enough for me to determine that the thermometer on the right was a hygrometer. Aiding that assumption was the fact that thermometers and hygrometers are sometimes paired together for observations.

> **Comments:**
> **username_0**: Ah, that makes sense. But the answer could use a bit more detail.  
> **username_2**: It would be great if you included a link or an example of the calculation, the OP and other readers will find it more instructive. I have a we/dry setup at home and I always have to read the table on the back of the box to get humidity. If there's an equation or something it would be great to know. Thanks!  
> **username_3**: @username_2: If it is a wet bulb thermometer the relative humidity would be 32% & the dew point would be approx. 1.5 C - according to the spreadsheet I wrote years ago. The relative humidity is vapor pressure divided by saturated vapor pressure @ dry bulb. To get vapor pressure, another 5 or so calculations need to be done: moisture content, moist cont @ wet bulb, enthalpy of vapor press @ wet bulb, enthalpy of liquid water @ wet bulb, enthalpy of vapor press @ dry bulb. Nothing difficult, just time consuming.  
> **username_2**: @username_3 got it, thanks! I'll look around, and if I don't find an existing Q&A then maybe I'll ask a new question.  
> **username_2**: @username_3 I've just asked: [How is relative humidity determined from a wet and dry bulb readings?](https://earthscience.stackexchange.com/q/19151/6031)  
> **username_1**: @username_0 Edited in my process, hope that helps!  

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