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  1. J

    Historic temperature data in New York/Greenwich on small and large time scales

    I cannot speak to the billion years, but the last decade of New York, is covered fairly well by NOAA's climate at a glance. https://www.ncdc.noaa.gov/cag/city/time-series
  2. J

    Wind chill -- How is it actually measured?

    I think of wind chill as how quickly heat is removed from an object, the object can be ether a person or a bowl of water. The persons perspective is subjective, the bowl of water freezing solid is not.
  3. J

    Wind chill -- How is it actually measured?

    Since how something feels is very subjective, I would hope the formula is based on empirical data. For me a type of real measurement would be the time difference between a bowl of water at say -5 C without air movement to freeze solid vs the time with a 10 knot wind. The moving air would cause...
  4. J

    Secondary Mirror in Solar Concentrator Dish Designs

    The only limitation I can think of would be a concern for air ionization. As the energy density increases in the ever tightening focused beam, you might pass the point where the air ionized and becomes less transparent. This can be observed with lasers or just a few watts, the power observed at...
  5. J

    B Recreation of Famous Japanese Rogue Wave

    I understand, I was simply trying to show that the possibility for rouge wave exists in the math as well. You are correct that the randomness of waves of different directions, amplitudes, and frequencies would make the actual peak interference very rare.
  6. J

    B Quartz vs. Glass -- why do they have different melting points?

    A word of caution, if you are used to working with glass, quartz looks like it has cooled off long before it actually has.
  7. J

    Where can I find historic daily average temperatures?

    I think NOAA's climate at a glance has what you may be looking for. https://www.ncdc.noaa.gov/cag/city/time-series/USW00094728/tavg/12/12/1895-2018?base_prd=true&firstbaseyear=1901&lastbaseyear=2000&trend=true&trend_base=10&firsttrendyear=1895&lasttrendyear=2018 It also can do maximum and...
  8. J

    Storing Heat from a Radiator

    You might try finding a 30 gallon barrel and filling it with rocks and water, and placing it in contact with the radiator. (Perhaps do not seal the barrel) The mass of the rocks and water would warm up with the radiator, but then take several hours to cool down after the source of the heat...
  9. J

    B Recreation of Famous Japanese Rogue Wave

    I think we think of waves and constructive interference in 2 dimensions, and with mostly 2 frequencies. In the ocean there can be several vectors of energy, and water supports a wide range of frequencies. I recall something I worked on a few decades ago, where the summation maxima s were not the...
  10. J

    How do we know electromagnetic waves are light?

    C/wavelength=frequency, C/frequency=Wavelength
  11. J

    How do we know electromagnetic waves are light?

    When it meets those criteria, it behaves like a wave, and works with the wave equations. You could say most of the same things for sound waves, but the "c" is different.
  12. J

    How do we know electromagnetic waves are light?

    I would say that if c(the speed of light) is divided by ether the frequency or wavelength, and the result is the one you did not divide by, then it counts as light.
  13. J

    Are there other variables that control climate change?

    You would think, but IPCC AR5 in 2013 cited Baede as the more comprehensive assessment. https://www.ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_Chapter01_FINAL.pdf "Here, some of the key concepts in climate science are briefly described; many of these were summarized more comprehensively in...
  14. J

    Are there other variables that control climate change?

    The largest area of uncertainty in the climate models is based on our poor understanding of how clouds interact with radiation, Baede et al 2001 IPCC TAR, "It is believed that the overall effect of the feedbacks amplifies the temperature increase to 1.5 to 4.5°C. A significant part of this...
  15. J

    How do you run vacuum pumps in series?

    For high vacuum systems you use two pumps effectively in series. The roughing pump is attached at the bottom of the diffusion pump, and lowers the pressure to between viscous flow and molecular flow. The diffusion pump takes over, and collects molecules at the bottom for the roughing pump to...
  16. J

    Seismology and oil exploration

    I have to agree with Dave, I took several research projects offshore on working seismic ships, and there were not any trails of dead fish behind the ships. If there had been there would also be a trail of sea gulls, like what follow a shrimp boat. Air Guns are much better seismic sources than...
  17. J

    42% of Sea Level rise due to human water use?

    I think I would have to take issue with the level that ground water has declined. If the ground water dropped by 30 feet anywhere, many wells would no longer function. I am in the Houston area, and there are many layers of water, the first being at only about 20 feet, and there are many...
  18. J

    Underwater sculpture

    Perhaps a more empirical approach might be better than the analytical one. This has been done before, and there are even videos describing the efforts. Most artists would likely talk to you about what the complications are, the worst they could say is, "no" they won't talk to you.
  19. J

    I Atmospheric CO2 and diurnal Asymmetry

    Sorry, Most of the discussions of energy states of atmospheric nitrogen revolve around much higher energy states. http://iopscience.iop.org/article/10.1088/1367-2630/11/6/065011/meta This air fluorescence demonstrates that excited nitrogen exists in the atmosphere. They even mention that, "2.2...
  20. J

    I Atmospheric CO2 and diurnal Asymmetry

    We know it happens at atmospheric range pressures in the lab, the question is why would it not happen in the atmosphere? The real question is if the artifacts of these energy transitions are detectable, i.e. are the 9.6 and 10.6 um bands more pronounced during the sunlight hours?
  21. J

    I Atmospheric CO2 and diurnal Asymmetry

    Nitrogen does not need laser light to be excited, simply a photon in it's absorption band (Roughly 3.8 to 5 um) CO2 does have a meta stable state at the .2 eV level, which can cause a population inversion and limit power in a laser. Helium is used in the gas mixture, to allow more molecules to...
  22. J

    I Atmospheric CO2 and diurnal Asymmetry

    What I am thinking is that during the sunlight hours, the CO2 quickly gets into a population inversion state, and a much lower percentage of CO2 molecules are available to intercept IR. Since the observed diurnal asymmetry is roughly 3:1 night vs daytime warming,(Karl et al 1993) the effective...
  23. J

    How does lifetime of a cyclone affect: precipitation and intensity

    I think it is more complex than that, because the longer a cyclone lives the more it is also exposed to things that can tear it apart. From what I have seen precipitation intensities does not increase, (thank goodness it is bad enough already). They calculated the possible rainfall totals for...
  24. J

    I Atmospheric CO2 and diurnal Asymmetry

    Something that has bothered me is that CO2 appears to have a much greater role after dark than in the daytime. I was wondering if this is because of a CO2 population inversion during the sunlight hours. I am thinking that Sunlight and daytime blue sky, excite atmospheric nitrogen, The nitrogen...
  25. J

    Water cooling for trout ponds in the South African summer

    Depending on what the dew point is, and if water is cheap and easy, there may be more benefit to running the aerators during the daytime. The greatest difference between the dew point and the air temperature is usually mid afternoon. You would loose more water, but also do a lot more cooling...
  26. J

    Mean Earth temperature

    I understand that each method could show an anomaly change, I take from the GISS statement, that they do not know which method was used in the collection from the different reporting stations.
  27. J

    Water cooling for trout ponds in the South African summer

    I would start with looking at what the dew point is in your area. If the dew point (wet bulb) temperature is 3 or more degrees C colder than the daytime highs, then some solar power fountains could help a lot with evaporation cooling.
  28. J

    Mean Earth temperature

    I am not sure we could actually state a mean earth temperature, and have it mean much of anything. The GISS states in their Q&A that they do not have a standard collection methodology. https://data.giss.nasa.gov/gistemp/faq/abs_temp.html ""Q. What do we mean by daily mean SAT? A. Again, there is...
  29. J

    Bolt alternatives (foot operated)

    I have a cam clamp on the bottom of a table saw, that is foot operated...
  30. J

    High Temperature, Non-conductive Material

    Crystal aluminum oxide, might do the trick (Garnet) It can take high temperatures, and is about the toughest material going. Slightly less hard than diamond, but very mechanically stable.
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