Climate Alarmist, PhD Physicist David Appell Fails Freshman Physics… Misunderstands Climate-Critical Evaporation

A comment by PhD physicist David Appell, a contributing writer to Scientific American and Nature,  shows he does not understand the fundamental climate-driving mechanism of water evaporation in a recent comment. 

Amazon rain forest still exists despite very warm, year-round temperatures. Image cropped: NASA

Many readers are familiar with climate alarm dogmatist David Appell. He sometimes goes off on comment tirades here at NTZ, getting huffed up.

Though a large part of his dogma-filled comments fail to meet editorial standards, and so don’t get published, some have merit and are welcome.

Doesn’t understand evaporation

Recently I decided to leave up one of his comments, though it was a falsehood. I did so because it illustrates how this Physics PhD really does not even understand the basic physics behind water evaporation – a critical element in our climate system. If you don’t understand how evaporation works, how can you possibly understand how climate works, let alone model it?

Appell’s gaffe comment came in response to the recent NTZ article: “Alarmist Claims Of Increasing European Drought Are A Myth“, to which he commented

Though it may be counter-intuitive to some, Appell’s statement is false. Indeed many laypersons believe that heat (higher temperatures) do dry things out. For example, we throw our wet clothes in the dryer because “the heat dries them”. But it isn’t quite so. Heat is not what dries, and PhD physicist David Appell really should know better. Drying depends on the relative humidity, and not on temperature.

Wet jungles, desert polar regions

According to Mr. Appell’s understanding, hot jungles, where hot temperatures of 35°C persist, should have dried out long ago. But they haven’t. They don’t dry out because of their high relative humidity that keeps them green and lush. It has nothing to do with temperature.

In fact, as reader Yonason points out, some of the largest deserts in the world are located in extremely cold regions. Temperature is not what drives drought! Lack of moisture is what does it, and nothing else. In fact, the driest periods on earth have occurred in cold periods.

Other “experts” also misunderstood

David Appell is not the only “expert” who misunderstand what drives evaporation. German “expert” Volker Quaschning also misunderstood it last year. Veteran Swiss meteorologist Jörg Kachelmann had to sit him down and school him on the subject. It’s no wonder many alarmists and modelers have been so wrong when it comes to climate change.

Lack of quality control

And one really has to pause and wonder about the quality control at renowned publications like Scientific American and Nature, who Appell claims he has written for,  that they would print material from persons who clearly do not understand the fundamental physics of water vapor – a crucial component of our climate system.

14 responses to “Climate Alarmist, PhD Physicist David Appell Fails Freshman Physics… Misunderstands Climate-Critical Evaporation”

  1. Scissor

    I thought may Appell had succumbed to CV-19 caught from his cat. Anyway, perhaps he should explain what he meant.

  2. Stephen Way

    Definition of an Expert.
    X is an unknown Quantity and a Spurt is a drip under pressure.
    Seems relevant here with Appell.

  3. Alan Tomalty

    I immediately started to laugh at the comment because I immediately realized that if evaporation levels increased, then absolute humidity levels would have to increase. This would eventually cause an increase in precipitation since the air can only hold a maximum amount of water vapour. What goes up MUST come down.

  4. Bruce of Newcastle

    I used to have epic blog arguments with Dave. He never won a single one. But then I’m a chemist with a lot of experience with thermodynamics, and have been analysing data for nearly 4 decades. The water cycle is key to the low CO2 ECS, which anyone who knows water chemistry and IR physical chemistry could easily work out.

  5. alf

    But does it not take cold air to condense the water?

    1. Stewart Pid

      Adiabatic cooling is the process of reducing heat through a change in air pressure caused by volume expansion. In data centers and other facilities, adiabatic processes have enabled free cooling methods, which use freely available natural phenomena to regulate temperature.

    2. The Indomitable Snowman, Ph.D.

      Air warms near the surface, becomes more buoyant, and rises. As it rises, it expands adiabatically and cools. When it has cooled to the point that the air temperature reaches the dewpoint temperature, visible moisture condenses out of the air.

      This is actually the major process by which heat energy is transferred from the surface to the upper atmosphere.

      And if you stare at it long enough, you’ll see that it’s basically a vertical Carnot cycle in operation.

  6. Yonason

    A cooler world with lower CO2 is a better world?

    Depends on your definition of “better.”

  7. tom0mason

    Appel has always shown himself as one who is totally taken with modelling the environment about himself, while having little if any regard for going out and actually taking measurements himself.
    He has never been very scientific for he places a huge amount if belief in mathematical modelling being able to reveal ‘the science’ of the climate. What he fails to understand is our knowledge (and thus the mathematics) is held back by our vast lack of observational data and understanding for weather and climate effects (water in all it’s forms in the environment and how and when it changes, how the jet-stream moves, where, when, why and how large and small storms occur, solar and cosmic effects, vocanoes and seismic effects, etc., etc.)

    Appel is just another wannabe climate pundit lost in his own virtualized computer world.

  8. The Indomitable Snowman, Ph.D.

    “And one really has to pause and wonder about the quality control at renowned publications like Scientific American and Nature…”

    Actually, it tells you all you need to know about those “renowned” [sic] publications.

    SA long ago sold out and became science-as-a-streetwalker for leftist idiocy. Nature did it a little later but it’s the same thing.

  9. Nieuws 3.7.2020 -

    […] Chronic Exposure of Adult Male Wistar Rats to Bisphenol A Causes Testicular Oxidative Stress Climate Alarmist, PhD Physicist David Appell Fails Freshman Physics Climate change caused havoc 2000 years ago Coronavirus affects the blood vessels as well as the […]

  10. Bob Armstrong

    Appel has been my ” house troll ” for years . He spends weekends dissing my week’s Disqus posts on almost any topic . ( Seems to have finally tiered of it lately . )

    Long ago I realized that he doesn’t even understand the concept of a lightSecond to convert between radiant spacial energy density and temporal power .

    He is an embarrassment to the Stony Brook NY university physics department and his advisor there .

  11. salah bela

    Merci pour cet article

  12. Yonason

By continuing to use the site, you agree to the use of cookies. more information

The cookie settings on this website are set to "allow cookies" to give you the best browsing experience possible. If you continue to use this website without changing your cookie settings or you click "Accept" below then you are consenting to this. More information at our Data Privacy Policy