Questions tagged [measurements]
Questions related to acquiring, processing and interpreting field measurements of any kind. Including instrumentation and data analysis.
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What was the global earth temperature before the industrial revolution?
I keep seeing that the rise in global temperature was measured against pre-industrial times. However, I can't find a global average for this period (circa 1700 to 1850). Because the Little Ice Age or ...
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How is rainfall measured when the news speaks of "two inches of rain"
I left a wheelbarrow outside overnight and it rained heavily. This morning, the water in the wheelbarrow is five (5) inches deep. It's not sitting under an eave where water might have been channeled ...
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What criteria determines whether earthquakes are classified as new or aftershocks?
I saw a recent paper where it is claimed that aftershocks can occur years, decades or centuries after the main earthquake.
When seismic activity is observed, what criteria determines the ...
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How to combine different air pollutants into a common measure?
I'm examining several pollutant variables -- like CO2, lead, NOX etc -- and wondering how I can weight them appropriately to have some kind of comparability. Not all pollutants are equally bad for the ...
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Why (and how) is particulate matter measured in mass per volume?
Why are particulate matter measurements (like PM2.5) from an air quality monitor given in micrograms per cubic meter (μg / mm^3)? Specifically, why mass?
I assume the device is using an optical ...
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Another question about the width of Khone Phapheng falls
In a previous question I asked why I can't measure the width of Khone Phapheng Falls; and I found out from the comments that I didn't take this into account that Khone Phapheng Falls are sets of falls ...
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Why can't I measure the width of a waterfall on Google Maps?
From the Wikipedia article for Khone Phapheng Falls:
It is the widest waterfall in the world at $10783$ metres ($35376$ feet or $6.7$ miles) in width from one edge of its multiple channels to the ...
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Estimate EPW AMY parameters from HRRR Analysis
I am working to create Energy Plus Weather (EPW) Actual Meteorological Year (AMY) files from NOAA HRRR Model analysis. The provided links detail the 35 parameters required for the AMY model and ...
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How to calculate wet bulb globe temperature (WBGT) using only temperature and humidity?
Greetings fellow scholars,
I'm trying to answer the question above because I've come across WBGT calculators like this one (https://www.climatechip.org/heat-stress-index-calculation) and I don't ...
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On defining a scale for anisotropy
My question is regarding the following statement given in this paper on page 51. It reads,
Fundamental to both anisotropy and heterogeneity is the concept of
scale. Whether anisotropy and ...
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How did they know that there was a "desert tsunami" in a Death Valley cave after a 7.6 magnitude earthquake near the southwest of Mexico?
Phys.org's story from September 23, 2022 entitled Mexico earthquake triggers 'desert tsunami' 1,500 miles away in Death Valley cave includes the following:
About five minutes after the 7.6 magnitude ...
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Atmospheric pressure: intra-day time series
I would like to get access to a time series of data on atmospheric pressure over a short timescale. I need to get a feel for how much variation there is over seconds and minutes, so a data point every ...
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How was the sea depth under the North Pole ice sheets measured?
Google Earth doesn't show the ice sheets of the North Pole, but the undersea depth. How was this depth measured, when most of this area is covered by ice all year round?
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How to measure Air CO2 Cheaply for a School Science Experiment
I'm helping my daughter with a science experiment for school to show the effect of CO2 enrichment on plant growth. We have two small tabletop greenhouses with approximately 10 Liter volume and we're ...
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Meterological measures -formula containing temperature, humidity, cloud, wind
I am looking for a meteorological measure (formula) of something which combines 2 or more of the following:
temperature,
humidity,
cloud,
wind,
precipitation,
UV
I have searched, and for example, ...
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Is there any measured atmospheric temperature profile made public?
I'm looking for a temperature-with-altitude measurement by a sounding rocket having gone through the tropo, strato- and mesosphere, have any such results been published after temperatures were ...
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Is there a certification process for automated weather stations?
I'm in the market for a new automated weather station and of course there's a glut of them on the internet. I mostly will be using the data for myself and my own amusement but do plan to submit ...
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Where can I find soil Free Swell Index values for the Cambridgeshire region, United Kingdom?
Where can I find Free Swell Index data for Clays for the Cambridgeshire region, United Kingdom?
Surely this must have been performed at some point even though there are more sophisticated tests. I've ...
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Interpreting Prospecting Ore Test Result
I need help in explaining the commercial viability of this potential Tantalum lab test result from Africa.
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How to interpret land use measures in environmental impact papers?
In reading some papers about the environmental impact of agricultural products such as crops and animal rearing, I am puzzled by the way land use is reported. I understand that inputs such as energy, ...
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How does a whirling hygrometer work, how does it differ from static dry/wet bulb thermometer, and how to obtain humidity from its readings?
Answers to my previous question How is relative humidity determined from a wet and dry bulb readings? provide equations for converting the two temperature measurements to a relative humidity.
In ...
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How to add scale in DSLR plus microscope set up by default?
We have an Axioscope microscope and planning to install a Nikon D5300 camera on top of it. The software I looked up, is DigiCam Control. The downside is we cannot add scale by default. The scale has ...
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Is there any information on the height of waves near New Zealand resulting from today's M 8.1 Kermadec Islands earthquake?
The video in this tweet shows the small wave produced at Tokomaru Bay in New Zealand following the M 8.1 - Kermadec Islands, New Zealand 2021-03-04 19:28:31 (UTC) event. These are so far the only ...
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What instrumentation and/or measurement is likely being shown in this video of giant Siberian craters/sinkholes?
The RT video The Permafrost Mystery: scientists explore giant Yamal Sinkhole (with English subtitles) shows scientists exploring the formation. In one scene after about ...
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How on "Earth" can you make all those measurements of Earth forming?
This question is a result of recent news that Earth had a "boring billion" years in which mountains ceased to grow, and subsequently hindered life evolution.
The article went on to give ...
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How to efficiently estimate merchentable volume for timber inventory using species, DBH, and merchentable heights?
I am trying to estimate wood volume for forest stands I have field-inventoried using a variable plot sample method, measuring species, DBH, and height of each tree counted 'in' using a BAF-10 prism. ...
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How would I compare (CO$_2$-eq) kg$^{−1}$ with metric tons?
I'm doing a project and looking at one of my scholarly resources, it says that
The carbon footprint per kilogram protein of plant-based
substitutes was found in the range of 6–17 carbon dioxide ...
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To what degree does historical measurement inaccuracies contribute to climate change models?
Often the graphs depicting the earth's historical temperature, the time axis extends well over couple of centuries. Also there are few that extends over thousands of years.
I wonder to what degree the ...
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Tipping bucket rain gauge measurement, normalizing
I have bought this cheap rain gauge (only the rain gauge, not the other parts) for measuring rainfall with a Raspberry Pi. It works as far as I can tell, every bucket swing will result in an interrupt ...
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Measuring the circumference of the earth - revisited
I have done a bit of research on this topic already and the easiest way seems to be the experiment by Eratosthenes. We pick two locations on the same latitude (of which we know the distance) and then ...
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Books / resources on measurement methods in atmospheric sciences
I have found this very long book from weather.gov (free access) Guide to Meteorological Instruments and Methods of Observation which might be a bit too in-depth for what I'm looking for, so I was ...
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How do we know the speed of S-waves (shear waves) in the Earth's inner core? Has this been measured?
Wikipedia's Seismic wave includes the plot below of the speed of S and P waves as a function of depth in the Earth. In the region of the outer core the speed of S-waves or shear waves is shown to be ...
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How much does COVID-19 affect weather forecasts?
The World Meteorological Organization (WMO) is concerned about the impact of the COVID-19 pandemic on the quantity and quality of weather observations and forecasts, as well as atmospheric and climate ...
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How many days has it been since the Cambrian explosion?
I want to know how to calculate the number of days since an event in Earth's past, and am using the Cambrian explosion as an example.
I define a day to be one rotation of Earth with respect to the ...
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Extent of desert area influence in local climate
With reference to this image...:
...from this recent tweet, I was wondering to what extent would Mediterranean regions be affected by the large desert areas to its South?
"Affected", here meaning ...
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How do the pros measure humidity?
I have used a wet/dry bulb setup to estimate humidity, and it appears that the Argentinian meteorological service uses one in Antarctica as well.
Wikipedia sez:
Humidity measurement is among the ...
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How is relative humidity determined from a wet and dry bulb readings?
The question What is the second thermometer in the image from the Esperanza Antarctic temperature record? shows what might be a wet/dry bulb setup.
I've given one to a friend to measure humidity for ...
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What is the second thermometer in the image from the Esperanza Antarctic temperature record?
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.
...
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What does a floating mercury barometer look like? How does it work and how is buoyancy used?
This answer to How are barometric pressure measurements traceable over centuries to 100 parts per million accuracy? describes a floating mercury barometer, and mentions that some employed a Vernier ...
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How are barometric pressure measurements traceable over centuries to 100 parts per million accuracy?
The BBC News item Barometric pressure in London 'highest in 300 years' at least begins with
Overnight, Sunday into Monday, London's Heathrow Airport recorded a barometric pressure of 1,049.6 ...
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How is land subsidence measured?
When groundwater is pumped out of the ground by wells, and not replenished fast enough, the groundwater level sinks.
With it, the surface of the area sinks also. Locally, this effect is not apparent,...
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Transmitter receiver coil separation for Electromagnetic Terrain Conductivity Measurement
Why increasing transmitter-receiver coil separation in EM survey (EM31, also here) increases depth of penetration?
Suppose there is a horizontal flat conductive layer underneath a flat resistive ...
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What was the lowest temperature ever recorded on the surface of Earth?
This article Lowest recorded temperatures lists a -89 Degrees Celsius in Vostok, Antartica as the lowest recorded temperature. However, this other article List of weather records lists a −93.2 °C (−...
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If the accuracy of measurement of the earth's volume is not known, how can scientists assert that the earth is not expanding?
Volcanic eruptions, undersea earthquakes, fissures in the crust, meteoroid accumulation could all be seen as empirical evidence of expansion of the earth. Sink holes and other phenomena could be ...
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Which is worse, plastic or styrofoam cups?
Which disposable cup between plastic and styrofoam harm the environment the most?
Which is the most unhealthy to use for the Earth for humans and animals?
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Atmospheric visibility measuring device
I have this project at university where I have to make an atmospheric visibility measuring device using Arduino. I talked with my teacher and he said that I should do something like this, using an ...
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Data for plotting tephigrams
I want to plot some tephigrams.
Where can I find pressure, temperature and dewpoint data in text format?
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What is a Rotating Shadowband Radiometer, and how does it work?
This answer explains that the device labeled "B" in the photo below is a "Ultraviolet Multifilter Rotating Shadowband Radiometer."
What is a Rotating Shadowband Radiometer, and how does it work?
...
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How temperature anomaly are measured
Temperature Anomaly is the measure used to show that the earth is warming. The formula for temperature anomaly involves in the subtraction of average temperature measurement over 30 years considered ...
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Unwarranted claim of higher degree of accuracy in zircon geochronology
The uncertainty in the half life of uranium-238 is stated at 0.05% [1]. The same paper gives the date 251.941 myr ± 31 kyr.
251.941 $\times$ 0.05% = 125 kyr.
How are the authors justified in ...
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