31

It's a Campbell-Stokes sunshine recorder, used to record the times at which the sun is shining. It acts as a lens, focusing the sunlight onto a piece of card. If the sun is shining, the focused beam will burn a hole through the card at that point. Here's a closer view of a sunshine recorder in Wendelstein, Bavaria: Source: Wikimedia Commons And here's a ...


17

Mark's answer about mercury barometers is correct - but it is not the complete story. Barometers were initially constructed using water, not mercury, on the manometer principle. Water is lighter than mercury, so a water barometer requires a 10.3m tube. 1mbar is therefore roughly 1cm, and 0.1mbar measurement is clearly trivial using a ruler with 1mm ...


16

If you're open to a more mechanical solution, I'd suggest building a "tipping bucket rain gauge", best explained by a picture (source: https://www.researchgate.net/figure/Sideview-of-tipping-bucket-Rain-Gauge_fig4_304297354): This should be relatively easy to build and it's trivial to read this electronically by detecting the time it takes to tip. ...


13

Upon reading the question my first thought was, please define what is meant by "how hard is it raining?". My initial tangent thought was "what about the impact energy of the rain" - heavy rain can be felt. Anyone who has heard rain fall on a metal or poly-carbonate roof will know the difference in noise produced by light and heavy rain. ...


12

One way to do that is to estimate how much water is changing. If you can ignore the spill over, then that is approximately how much the puddle is changing. Another idea you can use is to measure the changing weight of a rain gauge (that will need to be emptied daily, unless you can rig something that will do that for you). The faster the weight increases, ...


12

It's not perfect, but a simple solution to the issue of a puddle building up on the resistance plate is to tilt the plate a bit, so that instead of the water building up on the plate it runs off. Your device would then look for sudden drops in resistance, indicating that a droplet has formed on the device, followed by the resistance rising again after the ...


9

A mercury barometer is a simple, easy-to-build barometer that turns the problem of calibrating a pressure standard into one of calibrating a length standard. Accuracy of length standards has long been a concern of merchants and those regulating them; in 1692, the standard would probably have been a brass prototype yard in the possession of the Royal Society....


9

Those are Sun/Moon multispectral photometers and ski radiometers. These are instruments that can scan the sky or track the Sun/Moon for direct measurements. They measure light intensity at multiple narrow wavelength bands, and are designed to measure atmospheric aerosols content and characteristics. The ones in the third image seem to be a CIMEL CE-138 Sun ...


8

I've built DIY conductivity probes for subglacial measurements. Unfortunately my sensors remain under ~100m of ice so I haven't be able to recover them to check the calibration, but for the same reason, I've taken multiple measurements to reduce calibration drift, as I'm unable to re-calibrate them. So far, they have produced sensible data for 2+ years, but ...


8

Yes, you can measure seismic energy with accelerometers. Most people do. There are three ways to measure seismic energy: by displacement $x$, velocity $\dot{x}$, or acceleration $\ddot{x}$. Loose-spring devices like geophones measure velocity; stiff-spring devices like MEMS and relative gravimeters measure acceleration: they are accelerometers. Those used ...


8

Nereus as is, is currently not replaceable, but it was insured at a replacement value of $3.1 million, and my understanding Woods Hole currently plans to replace it, though unlikely at this point that there's a solid timeline for this taking place. Landers, fish traps, and sediment core samplers will still be actively used, but again, these are not really ...


7

I think the greatest impact may be upon the careers of the investigators on the project. Decades of work can be invested in the planning and building of a submersible or space probe, it an inherently risky undertaking, if it gets destroyed in the process, who takes up the job of learning from the experience and trying again? Hopefully, institutions support ...


7

The magnitude of an earthquake is related to the total energy released, therefore to estimate it from a seismogram you need to know the distance to the source. In the case of the Richter scale for example, the relationship between magnitude and seismogram amplitude is defined for a standard distance. If you have only one seismograph, you can not triangulate ...


6

The upside down funnel-shaped attachment is used to prevent rain-water getting inside the inlet of instruments which analyse ambient air. Usually, these instruments are air pollution monitoring instruments like ozone analyser, carbon monoxide analyser, particle concentration analyser, etc. One may think why can't just use U-shaped tube (inlet). In case of U-...


6

On the synoptic scale (thinking along the lines of cyclones, weather fronts etc.), then that's a pretty significant drop in that amount of time. A bomb or explosive cycogenesis in meteorological terms is defined as a drop of at least 24mb in 24 hours, so your observation easily fits this description of being a significant rapid pressure change. There's a ...


6

I don't think they are using that level of accuracy for the old readings. Reporting pressure, in hPa, to one decimal place is being done for recent measurements. There are no values given for very old readings. As for the record reading of 1053.6 hPa for 1902, I suspect that is a mathematical conversion of a reading that was most likely recorded in inches ...


6

I am going to take a guess here because I have not used these instruments in real life but given the content of this Mauna Loa Observatory I Exploratorium video - fast forward the video to 3:43 and see the yankee name on that instrument. Then I did a google search on that and got this link - Yankee list of products So A is a Pyranometer and B is a ...


6

Edit: 1 May 2021 The following procedure uses the less accurate method from page 455 onward from the scanned sections of the book pictured below, from the original answer. The procedure is a multistage process ideally suited to either a spreadsheet or programming code. The equations use SI units. 1. Calculate the saturated vapor pressure at the dry bulb ...


5

I think answering your questions in reverse will make more sense. The "size" of PM is typically the aerodynamic/inertial impaction size, as you guessed. My standard reference for this is this paper. Their figure 8 is a rough schematic of where particles of different size deposit in the lungs. Things with very large or very small inertial impaction size get ...


5

I am going to just give a slightly different perspective to the answer above by actually naming the instrument in OP's question. Based on the name BSRN in OP's second image that actually translates to this institution - Baseline Surface Radiation Network the cylindrical instrument in the photograph shown is actually a pyrheliometer. In an earlier answer I ...


5

In the latest EOS number there is an interview with Woods Hole Oceanographic Institution's scientist Timothy Shank in which he responds to the question. It seems that we are back to just snapshots and grad samples of the hadal ecosystem. Eos: What research opportunities have been lost as a result of the loss of Nereus? Shank: The ability of Nereus to do ...


5

Carbon monoxide (CO), natural gas & hydrocarbons, VOCs, ammonia, etc. In this Chemistry SE answer and this Electronics SE question I discuss how the family of MOS gas sensors work. They can measure a large variety of different gasses that can react with atomic oxygen (O rather than $\small\mathsf{O_2}$). I'll quote from this question: ......


5

A good place to start would be with Fortin barometers. They were "commonly used at meteorological stations to measure atmospheric pressure". The advantages of this type of barometer are its portability (inverted), and that it permits the inspection of both free surfaces of mercury whose difference in level have to be measured. The major ...


5

I would approach this by counting pings on a plate with an attached piezo or microphone. The amplitude of the ping will give the volume of the drop and the number of pings the drop quantity. This is a more robust real-world interface than an electrode sensor.


5

A 'video disdrometer' is a device for characterizing raindrop size distributions. Professional versions (e.g A 1D distrometer) can use a video camera to image the shadow cast by water droplets moving in front of a bright light. So one DIY approach might be a camera imaging rain drops falling through a gap. Delft university have put up an instructable for an ...


4

Accelerometers, preferably triaxial (i.e., those that record horizontal and vertical motion). Beyond that your question is indeed a bit too open-ended. Some use many cheap MEMS (http://onlinelibrary.wiley.com/doi/10.1029/2008GL036572/epdf; https://www.theverge.com/circuitbreaker/2017/7/13/15963996/raspberry-pi-seismograph-early-warning-earthquakes; these are ...


4

I sort of accidentally did this in one of my projects in a complicated, backhanded sort of way. I installed 16 soil moisture sensors in my yard as part of an attempt to track the distribution of water in the soil of a flower garden. The sensors are battery powered. They transmit their data via Bluetooth Low Energy to a couple of WiFi enabled control nodes in ...


3

How are barometric pressure measurements traceable over centuries to 100 parts per million accuracy? To compare records of barometric temperature, this standard doesn't necessarily have to be met. Recording barometric pressure to 100 parts per million precision has been possible for centuries because it's reasonably trivial to observe movement of the level ...


3

Following @ Friddy's comment, I started reading Aethlabs AE51 FAQ and was quite surprised! While a conventional aethalometer use a long tape and move it to the new position after each measurement (which could be as fast as one measurement per minute), the compact device shown in the image in question uses a single filter position, and just keeps measuring as ...


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